From 0413eea9226cdcf1f9d36731001cefda47896b3b Mon Sep 17 00:00:00 2001 From: Alasdair Kergon Date: Mon, 20 May 2002 18:10:10 +0000 Subject: [PATCH] Remove old patch --- patches/linux-2.4.18-devmapper-ioctl.patch | 6671 -------------------- 1 file changed, 6671 deletions(-) delete mode 100644 patches/linux-2.4.18-devmapper-ioctl.patch diff --git a/patches/linux-2.4.18-devmapper-ioctl.patch b/patches/linux-2.4.18-devmapper-ioctl.patch deleted file mode 100644 index 615f815..0000000 --- a/patches/linux-2.4.18-devmapper-ioctl.patch +++ /dev/null @@ -1,6671 +0,0 @@ -diff -ruN linux-2.4.18/drivers/md/Config.in linux/drivers/md/Config.in ---- linux-2.4.18/drivers/md/Config.in Fri Sep 14 22:22:18 2001 -+++ linux/drivers/md/Config.in Tue Apr 23 22:39:09 2002 -@@ -14,5 +14,6 @@ - dep_tristate ' Multipath I/O support' CONFIG_MD_MULTIPATH $CONFIG_BLK_DEV_MD - - dep_tristate ' Logical volume manager (LVM) support' CONFIG_BLK_DEV_LVM $CONFIG_MD -+dep_tristate ' Device mapper support' CONFIG_BLK_DEV_DM $CONFIG_MD - - endmenu -diff -ruN linux-2.4.18/drivers/md/Makefile linux/drivers/md/Makefile ---- linux-2.4.18/drivers/md/Makefile Thu Dec 6 15:57:55 2001 -+++ linux/drivers/md/Makefile Tue Apr 23 22:39:09 2002 -@@ -4,9 +4,12 @@ - - O_TARGET := mddev.o - --export-objs := md.o xor.o -+export-objs := md.o xor.o dm-table.o dm-target.o kcopyd.o - list-multi := lvm-mod.o - lvm-mod-objs := lvm.o lvm-snap.o lvm-fs.o -+dm-mod-objs := dm.o dm-table.o dm-target.o dm-ioctl.o \ -+ dm-linear.o dm-stripe.o dm-snapshot.o dm-exception-store.o \ -+ kcopyd.o - - # Note: link order is important. All raid personalities - # and xor.o must come before md.o, as they each initialise -@@ -20,8 +23,12 @@ - obj-$(CONFIG_MD_MULTIPATH) += multipath.o - obj-$(CONFIG_BLK_DEV_MD) += md.o - obj-$(CONFIG_BLK_DEV_LVM) += lvm-mod.o -+obj-$(CONFIG_BLK_DEV_DM) += dm-mod.o - - include $(TOPDIR)/Rules.make - - lvm-mod.o: $(lvm-mod-objs) - $(LD) -r -o $@ $(lvm-mod-objs) -+ -+dm-mod.o: $(dm-mod-objs) -+ $(LD) -r -o $@ $(dm-mod-objs) -diff -ruN linux-2.4.18/drivers/md/dm-exception-store.c linux/drivers/md/dm-exception-store.c ---- linux-2.4.18/drivers/md/dm-exception-store.c Thu Jan 1 01:00:00 1970 -+++ linux/drivers/md/dm-exception-store.c Tue Apr 23 21:54:20 2002 -@@ -0,0 +1,720 @@ -+/* -+ * dm-snapshot.c -+ * -+ * Copyright (C) 2001-2002 Sistina Software (UK) Limited. -+ * -+ * This file is released under the GPL. -+ */ -+ -+#include "dm-snapshot.h" -+ -+#define SECTOR_SIZE 512 -+ -+/* -+ * Magic for persistent snapshots: "SnAp" - Feeble isn't it. -+ */ -+#define SNAP_MAGIC 0x70416e53 -+ -+/* -+ * The on-disk version of the metadata. Only applicable to -+ * persistent snapshots. -+ * There is no backward or forward compatibility implemented, snapshots -+ * with different disk versions than the kernel will not be usable. It is -+ * expected that "lvcreate" will blank out the start of the COW device -+ * before calling the snapshot constructor. -+ */ -+#define SNAPSHOT_DISK_VERSION 1 -+ -+/* -+ * Metadata format: (please keep this up-to-date!) -+ * Persistent snapshots have a 1 block header (see below for structure) at -+ * the very start of the device. The COW metadata starts at -+ * .start_of_exceptions. -+ * -+ * COW metadata is stored in blocks that are "extent-size" sectors long as -+ * an array of disk_exception structures in Little-Endian format. -+ * The last entry in this array has rsector_new set to 0 (this cannot be a -+ * legal redirection as the header is here) and if rsector_org has a value -+ * it is the sector number of the next COW metadata sector on the disk. if -+ * rsector_org is also zero then this is the end of the COW metadata. -+ * -+ * The metadata is written in hardblocksize lumps rather than in units of -+ * extents for efficiency so don't expect a whole extent to be zeroed out -+ * at any time. -+ * -+ * Non-persistent snapshots simple have redirected blocks stored -+ * (in chunk_size sectors) from hard block 1 to avoid inadvertantly -+ * creating a bad header. -+ */ -+ -+/* -+ * Internal snapshot structure -+ */ -+struct persistent_info { -+ /* Size of extents used for COW blocks */ -+ long extent_size; -+ -+ /* Number of the next free sector for COW/data */ -+ unsigned long next_free_sector; -+ -+ /* Where the metadata starts */ -+ unsigned long start_of_exceptions; -+ -+ /* Where we are currently writing the metadata */ -+ unsigned long current_metadata_sector; -+ -+ /* Index into disk_cow array */ -+ int current_metadata_entry; -+ -+ /* Index into mythical extent array */ -+ int current_metadata_number; -+ -+ /* Number of metadata entries in the disk_cow array */ -+ int highest_metadata_entry; -+ -+ /* Number of metadata entries per hard disk block */ -+ int md_entries_per_block; -+ -+ int full; -+ -+ /* kiobuf for doing I/O to header & metadata */ -+ struct kiobuf *cow_iobuf; -+ -+ /* -+ * Disk extent with COW data in it. as an array of -+ * exception tables. The first one points to the next -+ * block of metadata or 0 if this is the last -+ */ -+ struct disk_exception *disk_cow; -+}; -+ -+/* -+ * An array of these is held in each disk block. LE format -+ */ -+struct disk_exception { -+ uint64_t rsector_org; -+ uint64_t rsector_new; -+}; -+ -+/* -+ * Structure of a (persistent) snapshot header on disk. in LE format -+ */ -+struct snap_disk_header { -+ uint32_t magic; -+ -+ /* Simple, incrementing version. no backward compatibility */ -+ uint32_t version; -+ -+ /* In 512 byte sectors */ -+ uint32_t chunk_size; -+ -+ /* In 512 byte sectors */ -+ uint32_t extent_size; -+ uint64_t start_of_exceptions; -+ uint32_t full; -+}; -+ -+static inline struct persistent_info *get_info(struct exception_store *store) -+{ -+ return (struct persistent_info *) store->context; -+} -+ -+/* -+ * READ or WRITE some blocks to/from a device -+ */ -+static int do_io(int rw, struct kiobuf *iobuf, kdev_t dev, -+ unsigned long start, int nr_sectors) -+{ -+ int i, sectors_per_block, nr_blocks; -+ int blocksize = get_hardsect_size(dev); -+ int status; -+ -+ sectors_per_block = blocksize / SECTOR_SIZE; -+ -+ nr_blocks = nr_sectors / sectors_per_block; -+ start /= sectors_per_block; -+ -+ for (i = 0; i < nr_blocks; i++) -+ iobuf->blocks[i] = start++; -+ -+ iobuf->length = nr_sectors << 9; -+ -+ status = brw_kiovec(rw, 1, &iobuf, dev, iobuf->blocks, blocksize); -+ return (status != (nr_sectors << 9)); -+} -+ -+/* -+ * Write the latest COW metadata block. -+ */ -+static int write_metadata(struct dm_snapshot *s, struct persistent_info *pi) -+{ -+ kdev_t dev = s->cow->dev; -+ int blocksize = get_hardsect_size(dev); -+ int writesize = blocksize / SECTOR_SIZE; -+ -+ if (do_io(WRITE, pi->cow_iobuf, dev, -+ pi->current_metadata_sector, writesize) != 0) { -+ DMERR("Error writing COW block"); -+ return -1; -+ } -+ -+ return 0; -+} -+ -+/* -+ * Allocate a kiobuf. This is the only code nicked from the old -+ * snapshot driver and I've changed it anyway. -+ */ -+static int alloc_iobuf_pages(struct kiobuf *iobuf, int nr_sectors) -+{ -+ int nr_pages, r, i; -+ -+ if (nr_sectors > KIO_MAX_SECTORS) -+ return -1; -+ -+ nr_pages = nr_sectors / (PAGE_SIZE / SECTOR_SIZE); -+ r = expand_kiobuf(iobuf, nr_pages); -+ if (r) -+ goto out; -+ -+ r = -ENOMEM; -+ iobuf->locked = 1; -+ iobuf->nr_pages = 0; -+ for (i = 0; i < nr_pages; i++) { -+ struct page *page; -+ -+ page = alloc_page(GFP_KERNEL); -+ if (!page) -+ goto out; -+ -+ iobuf->maplist[i] = page; -+ LockPage(page); -+ iobuf->nr_pages++; -+ } -+ -+ iobuf->offset = 0; -+ r = 0; -+ -+ out: -+ return r; -+} -+ -+/* -+ * Read on-disk COW metadata and populate the hash table. -+ */ -+static int read_metadata(struct dm_snapshot *s, struct persistent_info *pi) -+{ -+ int status; -+ int i; -+ int entry = 0; -+ int map_page = 0; -+ int nr_sectors = pi->extent_size; -+ kdev_t dev = s->cow->dev; -+ int blocksize = get_hardsect_size(dev); -+ unsigned long cur_sector = pi->start_of_exceptions; -+ unsigned long last_sector; -+ unsigned long first_free_sector = 0; -+ int entries_per_page = PAGE_SIZE / sizeof(struct disk_exception); -+ struct disk_exception *cow_block; -+ struct kiobuf *read_iobuf; -+ int r = 0; -+ int devsize = get_dev_size(dev); -+ -+ /* -+ * Allocate our own iovec for this operation 'cos the -+ * others are way too small. -+ */ -+ if (alloc_kiovec(1, &read_iobuf)) { -+ DMERR("Error allocating iobuf for %s", kdevname(dev)); -+ return -1; -+ } -+ -+ if (alloc_iobuf_pages(read_iobuf, pi->extent_size)) { -+ DMERR("Error allocating iobuf space for %s", kdevname(dev)); -+ free_kiovec(1, &read_iobuf); -+ return -1; -+ } -+ cow_block = page_address(read_iobuf->maplist[0]); -+ -+ do { -+ /* Make sure the chain does not go off the end of -+ * the device, or backwards */ -+ if (cur_sector > devsize || cur_sector < first_free_sector) { -+ DMERR("COW table chain pointers are inconsistent, " -+ "can't activate snapshot"); -+ r = -1; -+ goto out; -+ } -+ -+ first_free_sector = max(first_free_sector, -+ cur_sector + pi->extent_size); -+ status = do_io(READ, read_iobuf, dev, cur_sector, nr_sectors); -+ if (status == 0) { -+ map_page = 0; -+ entry = 0; -+ -+ cow_block = page_address(read_iobuf->maplist[0]); -+ -+ /* Now populate the hash table from this data */ -+ for (i = 0; i <= pi->highest_metadata_entry && -+ cow_block[entry].rsector_new != 0; i++) { -+ -+ chunk_t old = -+ sector_to_chunk(s, -+ le64_to_cpu(cow_block -+ [entry]. -+ rsector_org)); -+ chunk_t new = -+ sector_to_chunk(s, -+ le64_to_cpu(cow_block -+ [entry]. -+ rsector_new)); -+ -+ if ((r = dm_add_exception(s, old, new))) -+ goto out; -+ -+ first_free_sector = max(first_free_sector, -+ (unsigned -+ long) (le64_to_cpu -+ (cow_block -+ [entry]. -+ rsector_new) + -+ s->chunk_size)); -+ -+ /* Do we need to move onto the next page? */ -+ if (++entry >= entries_per_page) { -+ entry = 0; -+ cow_block = -+ page_address(read_iobuf-> -+ maplist[++map_page]); -+ } -+ } -+ } else { -+ DMERR("Error reading COW metadata for %s", -+ kdevname(dev)); -+ r = -1; -+ goto out; -+ } -+ last_sector = cur_sector; -+ cur_sector = le64_to_cpu(cow_block[entry].rsector_org); -+ -+ } while (cur_sector != 0); -+ -+ pi->current_metadata_sector = last_sector + -+ map_page * PAGE_SIZE / SECTOR_SIZE + -+ entry / (SECTOR_SIZE / sizeof(struct disk_exception)); -+ pi->current_metadata_entry = entry; -+ pi->current_metadata_number = i; -+ pi->next_free_sector = first_free_sector; -+ -+ /* Copy last block into cow_iobuf */ -+ memcpy(pi->disk_cow, (char *) ((long) &cow_block[entry] - -+ ((long) &cow_block[entry] & -+ (blocksize - 1))), blocksize); -+ -+ out: -+ unmap_kiobuf(read_iobuf); -+ free_kiovec(1, &read_iobuf); -+ -+ return r; -+} -+ -+/* -+ * Read the snapshot volume header, returns 0 only if it read OK -+ * and it was valid. returns 1 if no header was found, -1 on -+ * error. All fields are checked against the snapshot structure -+ * itself to make sure we don't corrupt the data. -+ */ -+static int read_header(struct dm_snapshot *s, struct persistent_info *pi) -+{ -+ int status; -+ struct snap_disk_header *header; -+ kdev_t dev = s->cow->dev; -+ int blocksize = get_hardsect_size(dev); -+ unsigned long devsize; -+ -+ /* Get it */ -+ status = do_io(READ, pi->cow_iobuf, dev, 0L, blocksize / SECTOR_SIZE); -+ if (status != 0) { -+ DMERR("Snapshot dev %s error reading header", kdevname(dev)); -+ return -1; -+ } -+ -+ header = (struct snap_disk_header *) -+ page_address(pi->cow_iobuf->maplist[0]); -+ -+ /* -+ * Check the magic. It's OK if this fails, we just create -+ * a new snapshot header and start from scratch. -+ */ -+ if (le32_to_cpu(header->magic) != SNAP_MAGIC) { -+ return 1; -+ } -+ -+ /* Check the version matches */ -+ if (le32_to_cpu(header->version) != SNAPSHOT_DISK_VERSION) { -+ DMWARN("Snapshot dev %s version mismatch. Stored: %d, " -+ "driver: %d", kdevname(dev), -+ le32_to_cpu(header->version), SNAPSHOT_DISK_VERSION); -+ return -1; -+ } -+ -+ /* Check the chunk sizes match */ -+ if (le32_to_cpu(header->chunk_size) != s->chunk_size) { -+ DMWARN("Snapshot dev %s chunk size mismatch. Stored: %d, " -+ "requested: %ld", kdevname(dev), -+ le32_to_cpu(header->chunk_size), s->chunk_size); -+ return -1; -+ } -+ -+ /* Check the extent sizes match */ -+ if (le32_to_cpu(header->extent_size) != pi->extent_size) { -+ DMWARN("Snapshot dev %s extent size mismatch. Stored: %d, " -+ "requested: %ld", kdevname(dev), -+ le32_to_cpu(header->extent_size), pi->extent_size); -+ return -1; -+ } -+ -+ /* Get the rest of the data */ -+ pi->start_of_exceptions = le64_to_cpu(header->start_of_exceptions); -+ if (header->full) { -+ DMWARN("Snapshot dev %s is full. It cannot be used", -+ kdevname(dev)); -+ return -1; -+ } -+ -+ /* Validate against the size of the volume */ -+ devsize = get_dev_size(dev); -+ if (pi->start_of_exceptions > devsize) { -+ DMWARN("Snapshot metadata error on %s. start exceptions > " -+ "device size (%ld > %ld)", -+ kdevname(dev), pi->start_of_exceptions, devsize); -+ return -1; -+ } -+ -+ /* Read metadata into the hash table and update pointers */ -+ return read_metadata(s, pi); -+} -+ -+/* -+ * Write (or update) the header. The only time we should need to -+ * do an update is when the snapshot becomes full. -+ */ -+static int write_header(struct dm_snapshot *s, struct persistent_info *pi) -+{ -+ struct snap_disk_header *header; -+ struct kiobuf *head_iobuf; -+ kdev_t dev = s->cow->dev; -+ int blocksize = get_hardsect_size(dev); -+ int status; -+ -+ /* -+ * Allocate our own iobuf for this so we don't corrupt -+ * any of the other writes that may be going on. -+ */ -+ if (alloc_kiovec(1, &head_iobuf)) { -+ DMERR("Error allocating iobuf for header on %s", kdevname(dev)); -+ return -1; -+ } -+ -+ if (alloc_iobuf_pages(head_iobuf, PAGE_SIZE / SECTOR_SIZE)) { -+ DMERR("Error allocating iobuf space for header on %s", -+ kdevname(dev)); -+ free_kiovec(1, &head_iobuf); -+ return -1; -+ } -+ -+ header = (struct snap_disk_header *) -+ page_address(head_iobuf->maplist[0]); -+ -+ header->magic = cpu_to_le32(SNAP_MAGIC); -+ header->version = cpu_to_le32(SNAPSHOT_DISK_VERSION); -+ header->chunk_size = cpu_to_le32(s->chunk_size); -+ header->extent_size = cpu_to_le32(pi->extent_size); -+ header->full = cpu_to_le32(pi->full); -+ -+ header->start_of_exceptions = cpu_to_le64(pi->start_of_exceptions); -+ -+ /* Must write at least a full block */ -+ status = do_io(WRITE, head_iobuf, dev, 0, blocksize / SECTOR_SIZE); -+ -+ unmap_kiobuf(head_iobuf); -+ free_kiovec(1, &head_iobuf); -+ return status; -+} -+ -+static void destroy_persistent(struct exception_store *store) -+{ -+ struct persistent_info *pi = get_info(store); -+ unmap_kiobuf(pi->cow_iobuf); -+ free_kiovec(1, &pi->cow_iobuf); -+ kfree(pi); -+} -+ -+static int init_persistent(struct exception_store *store, int blocksize, -+ unsigned long extent_size, void **context) -+{ -+ struct persistent_info *pi = get_info(store); -+ struct dm_snapshot *s = store->snap; -+ int status; -+ -+ *context = "Error in disk header"; -+ /* Check for a header on disk and create a new one if not */ -+ if ((status = read_header(s, pi)) == 1) { -+ -+ /* Write a new header */ -+ pi->start_of_exceptions = pi->next_free_sector; -+ pi->next_free_sector += pi->extent_size; -+ pi->current_metadata_sector = pi->start_of_exceptions; -+ pi->current_metadata_entry = 0; -+ pi->current_metadata_number = 0; -+ -+ *context = "Unable to write snapshot header"; -+ if (write_header(s, pi) != 0) { -+ DMERR("Error writing header to snapshot volume %s", -+ kdevname(s->cow->dev)); -+ goto free_ret; -+ } -+ -+ /* Write a blank metadata block to the device */ -+ if (write_metadata(s, pi) != 0) { -+ DMERR("Error writing initial COW table to " -+ "snapshot volume %s", kdevname(s->cow->dev)); -+ goto free_ret; -+ } -+ } -+ -+ /* -+ * There is a header but it doesn't match - fail so we -+ * don't destroy what might be useful data on disk. If -+ * the user really wants to use this COW device for a -+ * snapshot then the first sector should be zeroed out -+ * first. -+ */ -+ if (status == -1) -+ goto free_ret; -+ -+ return 0; -+ -+ free_ret: -+ unmap_kiobuf(pi->cow_iobuf); -+ free_kiovec(1, &pi->cow_iobuf); -+ return -1; -+} -+ -+/* -+ * Finds a suitable destination for the exception. -+ */ -+static int prepare_persistent(struct exception_store *store, -+ struct exception *e) -+{ -+ struct persistent_info *pi = get_info(store); -+ struct dm_snapshot *s = store->snap; -+ offset_t dev_size; -+ -+ /* -+ * Check for full snapshot. Doing the size calculation here means that -+ * the COW device can be resized without us being told -+ */ -+ dev_size = get_dev_size(s->cow->dev); -+ if (pi->next_free_sector + s->chunk_size >= dev_size) { -+ /* Snapshot is full, we can't use it */ -+ DMWARN("Snapshot %s is full (sec=%ld, size=%ld)", -+ kdevname(s->cow->dev), -+ pi->next_free_sector + s->chunk_size, dev_size); -+ pi->full = 1; -+ -+ /* Mark it full on the device */ -+ write_header(s, pi); -+ -+ return -1; -+ -+ } else { -+ e->new_chunk = sector_to_chunk(s, pi->next_free_sector); -+ pi->next_free_sector += s->chunk_size; -+ } -+ -+ return 0; -+} -+ -+/* -+ * Add a new exception entry to the on-disk metadata. -+ */ -+static int commit_persistent(struct exception_store *store, struct exception *e) -+{ -+ struct persistent_info *pi = get_info(store); -+ struct dm_snapshot *s = store->snap; -+ -+ int i = pi->current_metadata_entry++; -+ unsigned long next_md_block = pi->current_metadata_sector; -+ -+ pi->current_metadata_number++; -+ -+ /* Update copy of disk COW */ -+ pi->disk_cow[i].rsector_org = -+ cpu_to_le64(chunk_to_sector(s, e->old_chunk)); -+ pi->disk_cow[i].rsector_new = -+ cpu_to_le64(chunk_to_sector(s, e->new_chunk)); -+ -+ /* Have we filled this extent ? */ -+ if (pi->current_metadata_number >= pi->highest_metadata_entry) { -+ /* Fill in pointer to next metadata extent */ -+ i++; -+ pi->current_metadata_entry++; -+ -+ next_md_block = pi->next_free_sector; -+ pi->next_free_sector += pi->extent_size; -+ -+ pi->disk_cow[i].rsector_org = cpu_to_le64(next_md_block); -+ pi->disk_cow[i].rsector_new = 0; -+ } -+ -+ /* Commit to disk */ -+ if (write_metadata(s, pi)) { -+ pi->full = 1; /* Failed. don't try again */ -+ return -1; -+ } -+ -+ /* -+ * Write a new (empty) metadata block if we are at the -+ * end of an existing block so that read_metadata finds a -+ * terminating zero entry. -+ */ -+ if (pi->current_metadata_entry == pi->md_entries_per_block) { -+ memset(pi->disk_cow, 0, PAGE_SIZE); -+ pi->current_metadata_sector = next_md_block; -+ -+ /* -+ * If this is also the end of an extent then go -+ * back to the start. -+ */ -+ if (pi->current_metadata_number >= pi->highest_metadata_entry) { -+ pi->current_metadata_number = 0; -+ -+ } else { -+ int blocksize = get_hardsect_size(s->cow->dev); -+ pi->current_metadata_sector += blocksize / SECTOR_SIZE; -+ } -+ -+ pi->current_metadata_entry = 0; -+ if (write_metadata(s, pi) != 0) { -+ pi->full = 1; -+ return -1; -+ } -+ } -+ -+ return 0; -+} -+ -+/* -+ * Sets the full flag in the metadata. A quick hack for now. -+ */ -+static void drop_persistent(struct exception_store *store) -+{ -+ get_info(store)->full = 1; -+ write_header(store->snap, get_info(store)); -+} -+ -+int dm_create_persistent(struct exception_store *store, struct dm_snapshot *s, -+ int blocksize, offset_t extent_size, void **error) -+{ -+ struct persistent_info *pi; -+ int i, r; -+ int cow_sectors; -+ -+ pi = kmalloc(sizeof(*pi), GFP_KERNEL); -+ if (!pi) -+ return -ENOMEM; -+ -+ memset(store, 0, sizeof(*store)); -+ store->destroy = destroy_persistent; -+ store->init = init_persistent; -+ store->prepare_exception = prepare_persistent; -+ store->commit_exception = commit_persistent; -+ store->drop_snapshot = drop_persistent; -+ store->snap = s; -+ store->context = pi; -+ -+ pi->extent_size = extent_size; -+ -+ /* Leave the first block alone */ -+ pi->next_free_sector = blocksize / SECTOR_SIZE; -+ pi->disk_cow = NULL; -+ -+ pi->highest_metadata_entry = (pi->extent_size * SECTOR_SIZE) / -+ sizeof(struct disk_exception) - 1; -+ pi->md_entries_per_block = blocksize / sizeof(struct disk_exception); -+ -+ /* Allocate and set up iobuf for metadata I/O */ -+ *error = "Unable to allocate COW iovec"; -+ if ((r = alloc_kiovec(1, &pi->cow_iobuf))) -+ return r; -+ -+ /* -+ * Allocate space for the COW buffer. It should be at -+ * least PAGE_SIZE. -+ */ -+ cow_sectors = blocksize / SECTOR_SIZE + PAGE_SIZE / SECTOR_SIZE; -+ *error = "Unable to allocate COW I/O buffer space"; -+ if ((r = alloc_iobuf_pages(pi->cow_iobuf, cow_sectors))) { -+ free_kiovec(1, &pi->cow_iobuf); -+ return r; -+ } -+ -+ for (i = 0; i < pi->cow_iobuf->nr_pages; i++) -+ memset(page_address(pi->cow_iobuf->maplist[i]), 0, PAGE_SIZE); -+ -+ pi->disk_cow = page_address(pi->cow_iobuf->maplist[0]); -+ return 0; -+} -+ -+/* -+ * Implementation of the store for non-persistent snapshots. -+ */ -+struct transient_c { -+ offset_t next_free; -+}; -+ -+void destroy_transient(struct exception_store *store) -+{ -+ kfree(store->context); -+} -+ -+int prepare_transient(struct exception_store *store, struct exception *e) -+{ -+ struct transient_c *tc = (struct transient_c *) store->context; -+ offset_t size = get_dev_size(store->snap->cow->dev); -+ -+ if (size < (tc->next_free + store->snap->chunk_size)) -+ return -1; -+ -+ e->new_chunk = sector_to_chunk(store->snap, tc->next_free); -+ tc->next_free += store->snap->chunk_size; -+ -+#if 0 -+ DMWARN("Preparing exception, chunk %lu -> %lu.", -+ (unsigned long) e->old_chunk, (unsigned long) e->new_chunk); -+#endif -+ -+ return 0; -+} -+ -+int dm_create_transient(struct exception_store *store, -+ struct dm_snapshot *s, int blocksize, void **error) -+{ -+ struct transient_c *tc; -+ -+ memset(store, 0, sizeof(*store)); -+ store->destroy = destroy_transient; -+ store->prepare_exception = prepare_transient; -+ store->snap = s; -+ -+ tc = kmalloc(sizeof(struct transient_c), GFP_KERNEL); -+ if (!tc) -+ return -ENOMEM; -+ -+ tc->next_free = 0; -+ store->context = tc; -+ -+ return 0; -+} -diff -ruN linux-2.4.18/drivers/md/dm-ioctl.c linux/drivers/md/dm-ioctl.c ---- linux-2.4.18/drivers/md/dm-ioctl.c Thu Jan 1 01:00:00 1970 -+++ linux/drivers/md/dm-ioctl.c Tue Apr 23 21:51:57 2002 -@@ -0,0 +1,588 @@ -+/* -+ * Copyright (C) 2001 Sistina Software (UK) Limited. -+ * -+ * This file is released under the GPL. -+ */ -+ -+#include "dm.h" -+ -+#include -+#include -+#include -+ -+static void free_params(struct dm_ioctl *param) -+{ -+ vfree(param); -+} -+ -+static int version(struct dm_ioctl *user) -+{ -+ return copy_to_user(user, DM_DRIVER_VERSION, sizeof(DM_DRIVER_VERSION)); -+} -+ -+static int copy_params(struct dm_ioctl *user, struct dm_ioctl **param) -+{ -+ struct dm_ioctl tmp, *dmi; -+ -+ if (copy_from_user(&tmp, user, sizeof(tmp))) -+ return -EFAULT; -+ -+ if (strcmp(DM_IOCTL_VERSION, tmp.version)) { -+ DMWARN("struct dm_ioctl version incompatible"); -+ return -EINVAL; -+ } -+ -+ if (tmp.data_size < sizeof(tmp)) -+ return -EINVAL; -+ -+ dmi = (struct dm_ioctl *) vmalloc(tmp.data_size); -+ if (!dmi) -+ return -ENOMEM; -+ -+ if (copy_from_user(dmi, user, tmp.data_size)) { -+ vfree(dmi); -+ return -EFAULT; -+ } -+ -+ *param = dmi; -+ return 0; -+} -+ -+static int validate_params(uint cmd, struct dm_ioctl *param) -+{ -+ /* Unless creating, either name of uuid but not both */ -+ if (cmd != DM_CREATE_CMD) { -+ if ((!*param->uuid && !*param->name) || -+ (*param->uuid && *param->name)) { -+ DMWARN("one of name or uuid must be supplied"); -+ return -EINVAL; -+ } -+ } -+ -+ /* Ensure strings are terminated */ -+ param->name[DM_NAME_LEN - 1] = '\0'; -+ param->uuid[DM_UUID_LEN - 1] = '\0'; -+ -+ return 0; -+} -+ -+/* -+ * Check a string doesn't overrun the chunk of -+ * memory we copied from userland. -+ */ -+static int valid_str(char *str, void *begin, void *end) -+{ -+ while (((void *) str >= begin) && ((void *) str < end)) -+ if (!*str++) -+ return 0; -+ -+ return -EINVAL; -+} -+ -+static int next_target(struct dm_target_spec *last, unsigned long next, -+ void *begin, void *end, -+ struct dm_target_spec **spec, char **params) -+{ -+ *spec = (struct dm_target_spec *) -+ ((unsigned char *) last + next); -+ *params = (char *) (*spec + 1); -+ -+ if (*spec < (last + 1) || ((void *) *spec > end)) -+ return -EINVAL; -+ -+ return valid_str(*params, begin, end); -+} -+ -+/* -+ * Checks to see if there's a gap in the table. -+ * Returns true iff there is a gap. -+ */ -+static int gap(struct dm_table *table, struct dm_target_spec *spec) -+{ -+ if (!table->num_targets) -+ return (spec->sector_start > 0) ? 1 : 0; -+ -+ if (spec->sector_start != table->highs[table->num_targets - 1] + 1) -+ return 1; -+ -+ return 0; -+} -+ -+static int populate_table(struct dm_table *table, struct dm_ioctl *args) -+{ -+ int i = 0, r, first = 1, argc; -+ struct dm_target_spec *spec; -+ char *params, *argv[MAX_ARGS]; -+ struct target_type *ttype; -+ void *context, *begin, *end; -+ offset_t highs = 0; -+ -+ if (!args->target_count) { -+ DMWARN("populate_table: no targets specified"); -+ return -EINVAL; -+ } -+ -+ begin = (void *) args; -+ end = begin + args->data_size; -+ -+#define PARSE_ERROR(msg) {DMWARN(msg); return -EINVAL;} -+ -+ for (i = 0; i < args->target_count; i++) { -+ -+ r = first ? next_target((struct dm_target_spec *) args, -+ args->data_start, -+ begin, end, &spec, ¶ms) : -+ next_target(spec, spec->next, begin, end, &spec, ¶ms); -+ -+ if (r) -+ PARSE_ERROR("unable to find target"); -+ -+ /* Look up the target type */ -+ ttype = dm_get_target_type(spec->target_type); -+ if (!ttype) -+ PARSE_ERROR("unable to find target type"); -+ -+ if (gap(table, spec)) -+ PARSE_ERROR("gap in target ranges"); -+ -+ /* Split up the parameter list */ -+ if (split_args(MAX_ARGS, &argc, argv, params) < 0) -+ PARSE_ERROR("Too many arguments"); -+ -+ /* Build the target */ -+ if (ttype->ctr(table, spec->sector_start, spec->length, -+ argc, argv, &context)) { -+ DMWARN("%s: target constructor failed", -+ (char *) context); -+ return -EINVAL; -+ } -+ -+ /* Add the target to the table */ -+ highs = spec->sector_start + (spec->length - 1); -+ if (dm_table_add_target(table, highs, ttype, context)) -+ PARSE_ERROR("internal error adding target to table"); -+ -+ first = 0; -+ } -+ -+#undef PARSE_ERROR -+ -+ r = dm_table_complete(table); -+ return r; -+} -+ -+/* -+ * Round up the ptr to the next 'align' boundary. Obviously -+ * 'align' must be a power of 2. -+ */ -+static inline void *align_ptr(void *ptr, unsigned int align) -+{ -+ align--; -+ return (void *) (((unsigned long) (ptr + align)) & ~align); -+} -+ -+/* -+ * Copies a dm_ioctl and an optional additional payload to -+ * userland. -+ */ -+static int results_to_user(struct dm_ioctl *user, struct dm_ioctl *param, -+ void *data, unsigned long len) -+{ -+ int r; -+ void *ptr = NULL; -+ -+ strncpy(param->version, DM_IOCTL_VERSION, sizeof(param->version)); -+ -+ if (data) { -+ ptr = align_ptr(user + 1, sizeof(unsigned long)); -+ param->data_start = ptr - (void *) user; -+ } -+ -+ r = copy_to_user(user, param, sizeof(*param)); -+ if (r) -+ return r; -+ -+ if (data) { -+ if (param->data_start + len > param->data_size) -+ return -ENOSPC; -+ r = copy_to_user(ptr, data, len); -+ } -+ -+ return r; -+} -+ -+/* -+ * Fills in a dm_ioctl structure, ready for sending back to -+ * userland. -+ */ -+static void __info(struct mapped_device *md, struct dm_ioctl *param) -+{ -+ param->flags = DM_EXISTS_FLAG; -+ if (md->suspended) -+ param->flags |= DM_SUSPEND_FLAG; -+ if (md->read_only) -+ param->flags |= DM_READONLY_FLAG; -+ -+ strncpy(param->name, md->name, sizeof(param->name)); -+ -+ if (md->uuid) -+ strncpy(param->uuid, md->uuid, sizeof(param->uuid) - 1); -+ else -+ param->uuid[0] = '\0'; -+ -+ param->open_count = md->use_count; -+ param->dev = kdev_t_to_nr(md->dev); -+ param->target_count = md->map->num_targets; -+} -+ -+/* -+ * Always use UUID for lookups if it's present, otherwise use name. -+ */ -+static inline char *lookup_name(struct dm_ioctl *param) -+{ -+ return (*param->uuid) ? param->uuid : param->name; -+} -+ -+static inline int lookup_type(struct dm_ioctl *param) -+{ -+ return (*param->uuid) ? DM_LOOKUP_BY_UUID : DM_LOOKUP_BY_NAME; -+} -+ -+/* -+ * Copies device info back to user space, used by -+ * the create and info ioctls. -+ */ -+static int info(struct dm_ioctl *param, struct dm_ioctl *user) -+{ -+ struct mapped_device *md; -+ -+ param->flags = 0; -+ -+ md = dm_get_name_r(lookup_name(param), lookup_type(param)); -+ if (!md) -+ /* -+ * Device not found - returns cleared exists flag. -+ */ -+ goto out; -+ -+ __info(md, param); -+ dm_put_r(md); -+ -+ out: -+ return results_to_user(user, param, NULL, 0); -+} -+ -+/* -+ * Retrieves a list of devices used by a particular dm device. -+ */ -+static int dep(struct dm_ioctl *param, struct dm_ioctl *user) -+{ -+ int count, r; -+ struct mapped_device *md; -+ struct list_head *tmp; -+ size_t len = 0; -+ struct dm_target_deps *deps = NULL; -+ -+ md = dm_get_name_r(lookup_name(param), lookup_type(param)); -+ if (!md) -+ goto out; -+ -+ /* -+ * Setup the basic dm_ioctl structure. -+ */ -+ __info(md, param); -+ -+ /* -+ * Count the devices. -+ */ -+ count = 0; -+ list_for_each(tmp, &md->map->devices) -+ count++; -+ -+ /* -+ * Allocate a kernel space version of the dm_target_status -+ * struct. -+ */ -+ len = sizeof(*deps) + (sizeof(*deps->dev) * count); -+ deps = kmalloc(len, GFP_KERNEL); -+ if (!deps) { -+ dm_put_r(md); -+ return -ENOMEM; -+ } -+ -+ /* -+ * Fill in the devices. -+ */ -+ deps->count = count; -+ count = 0; -+ list_for_each(tmp, &md->map->devices) { -+ struct dm_dev *dd = list_entry(tmp, struct dm_dev, list); -+ deps->dev[count++] = kdev_t_to_nr(dd->dev); -+ } -+ dm_put_r(md); -+ -+ out: -+ r = results_to_user(user, param, deps, len); -+ -+ kfree(deps); -+ return r; -+} -+ -+static int create(struct dm_ioctl *param, struct dm_ioctl *user) -+{ -+ int r, ro; -+ struct dm_table *t; -+ int minor; -+ -+ r = dm_table_create(&t); -+ if (r) -+ return r; -+ -+ r = populate_table(t, param); -+ if (r) { -+ dm_table_destroy(t); -+ return r; -+ } -+ -+ minor = (param->flags & DM_PERSISTENT_DEV_FLAG) ? -+ MINOR(to_kdev_t(param->dev)) : -1; -+ -+ ro = (param->flags & DM_READONLY_FLAG) ? 1 : 0; -+ -+ r = dm_create(param->name, param->uuid, minor, ro, t); -+ if (r) { -+ dm_table_destroy(t); -+ return r; -+ } -+ -+ r = info(param, user); -+ return r; -+} -+ -+static int remove(struct dm_ioctl *param) -+{ -+ int r; -+ struct mapped_device *md; -+ -+ md = dm_get_name_w(lookup_name(param), lookup_type(param)); -+ if (!md) -+ return -ENXIO; -+ -+ r = dm_destroy(md); -+ dm_put_w(md); -+ if (!r) -+ kfree(md); -+ -+ return r; -+} -+ -+static int suspend(struct dm_ioctl *param) -+{ -+ int r; -+ struct mapped_device *md; -+ -+ md = dm_get_name_w(lookup_name(param), lookup_type(param)); -+ if (!md) -+ return -ENXIO; -+ -+ r = (param->flags & DM_SUSPEND_FLAG) ? dm_suspend(md) : dm_resume(md); -+ dm_put_w(md); -+ -+ return r; -+} -+ -+static int reload(struct dm_ioctl *param, struct dm_ioctl *user) -+{ -+ int r; -+ struct mapped_device *md; -+ struct dm_table *t; -+ -+ r = dm_table_create(&t); -+ if (r) -+ return r; -+ -+ r = populate_table(t, param); -+ if (r) { -+ dm_table_destroy(t); -+ return r; -+ } -+ -+ md = dm_get_name_w(lookup_name(param), lookup_type(param)); -+ if (!md) { -+ dm_table_destroy(t); -+ return -ENXIO; -+ } -+ -+ r = dm_swap_table(md, t); -+ if (r) { -+ dm_put_w(md); -+ dm_table_destroy(t); -+ return r; -+ } -+ -+ dm_set_ro(md, (param->flags & DM_READONLY_FLAG) ? 1 : 0); -+ dm_put_w(md); -+ -+ r = info(param, user); -+ return r; -+} -+ -+static int rename(struct dm_ioctl *param) -+{ -+ char *newname = (char *) param + param->data_start; -+ -+ if (valid_str(newname, (void *) param, -+ (void *) param + param->data_size) || -+ dm_set_name(lookup_name(param), lookup_type(param), newname)) { -+ DMWARN("Invalid new logical volume name supplied."); -+ return -EINVAL; -+ } -+ -+ return 0; -+} -+ -+static int ctl_open(struct inode *inode, struct file *file) -+{ -+ /* only root can open this */ -+ if (!capable(CAP_SYS_ADMIN)) -+ return -EACCES; -+ -+ MOD_INC_USE_COUNT; -+ -+ return 0; -+} -+ -+static int ctl_close(struct inode *inode, struct file *file) -+{ -+ MOD_DEC_USE_COUNT; -+ return 0; -+} -+ -+static int ctl_ioctl(struct inode *inode, struct file *file, -+ uint command, ulong u) -+{ -+ int r = 0; -+ struct dm_ioctl *param; -+ struct dm_ioctl *user = (struct dm_ioctl *) u; -+ uint cmd = _IOC_NR(command); -+ -+ /* Process commands without params first - always return version */ -+ switch (cmd) { -+ case DM_REMOVE_ALL_CMD: -+ dm_destroy_all(); -+ case DM_VERSION_CMD: -+ return version(user); -+ default: -+ break; -+ } -+ -+ r = copy_params(user, ¶m); -+ if (r) -+ goto err; -+ -+ r = validate_params(cmd, param); -+ if (r) { -+ free_params(param); -+ goto err; -+ } -+ -+ switch (cmd) { -+ case DM_INFO_CMD: -+ r = info(param, user); -+ break; -+ -+ case DM_SUSPEND_CMD: -+ r = suspend(param); -+ break; -+ -+ case DM_CREATE_CMD: -+ r = create(param, user); -+ break; -+ -+ case DM_RELOAD_CMD: -+ r = reload(param, user); -+ break; -+ -+ case DM_REMOVE_CMD: -+ r = remove(param); -+ break; -+ -+ case DM_RENAME_CMD: -+ r = rename(param); -+ break; -+ -+ case DM_DEPS_CMD: -+ r = dep(param, user); -+ break; -+ -+ default: -+ DMWARN("dm_ctl_ioctl: unknown command 0x%x", command); -+ r = -EINVAL; -+ } -+ -+ free_params(param); -+ return r; -+ -+ err: -+ version(user); -+ return r; -+} -+ -+static struct file_operations _ctl_fops = { -+ open: ctl_open, -+ release: ctl_close, -+ ioctl: ctl_ioctl, -+ owner: THIS_MODULE, -+}; -+ -+static devfs_handle_t _ctl_handle; -+ -+static struct miscdevice _dm_misc = { -+ minor: MISC_DYNAMIC_MINOR, -+ name: DM_NAME, -+ fops: &_ctl_fops -+}; -+ -+/* Create misc character device and link to DM_DIR/control */ -+int __init dm_interface_init(void) -+{ -+ int r; -+ char rname[64]; -+ -+ r = misc_register(&_dm_misc); -+ if (r) { -+ DMERR("misc_register failed for control device"); -+ return r; -+ } -+ -+ r = devfs_generate_path(_dm_misc.devfs_handle, rname + 3, -+ sizeof rname - 3); -+ if (r == -ENOSYS) -+ return 0; /* devfs not present */ -+ -+ if (r < 0) { -+ DMERR("devfs_generate_path failed for control device"); -+ goto failed; -+ } -+ -+ strncpy(rname + r, "../", 3); -+ r = devfs_mk_symlink(NULL, DM_DIR "/control", -+ DEVFS_FL_DEFAULT, rname + r, &_ctl_handle, NULL); -+ if (r) { -+ DMERR("devfs_mk_symlink failed for control device"); -+ goto failed; -+ } -+ devfs_auto_unregister(_dm_misc.devfs_handle, _ctl_handle); -+ -+ return 0; -+ -+ failed: -+ misc_deregister(&_dm_misc); -+ return r; -+} -+ -+void dm_interface_exit(void) -+{ -+ if (misc_deregister(&_dm_misc) < 0) -+ DMERR("misc_deregister failed for control device"); -+} -diff -ruN linux-2.4.18/drivers/md/dm-linear.c linux/drivers/md/dm-linear.c ---- linux-2.4.18/drivers/md/dm-linear.c Thu Jan 1 01:00:00 1970 -+++ linux/drivers/md/dm-linear.c Tue Jan 15 19:53:55 2002 -@@ -0,0 +1,105 @@ -+/* -+ * Copyright (C) 2001 Sistina Software (UK) Limited. -+ * -+ * This file is released under the GPL. -+ */ -+ -+#include "dm.h" -+ -+#include -+#include -+#include -+ -+/* -+ * Linear: maps a linear range of a device. -+ */ -+struct linear_c { -+ long delta; /* FIXME: we need a signed offset type */ -+ struct dm_dev *dev; -+}; -+ -+/* -+ * Construct a linear mapping: -+ */ -+static int linear_ctr(struct dm_table *t, offset_t b, offset_t l, -+ int argc, char **argv, void **context) -+{ -+ struct linear_c *lc; -+ unsigned long start; /* FIXME: unsigned long long */ -+ char *end; -+ -+ if (argc != 2) { -+ *context = "dm-linear: Not enough arguments"; -+ return -EINVAL; -+ } -+ -+ lc = kmalloc(sizeof(*lc), GFP_KERNEL); -+ if (lc == NULL) { -+ *context = "dm-linear: Cannot allocate linear context"; -+ return -ENOMEM; -+ } -+ -+ start = simple_strtoul(argv[1], &end, 10); -+ if (*end) { -+ *context = "dm-linear: Invalid device sector"; -+ goto bad; -+ } -+ -+ if (dm_table_get_device(t, argv[0], start, l, &lc->dev)) { -+ *context = "dm-linear: Device lookup failed"; -+ goto bad; -+ } -+ -+ lc->delta = (int) start - (int) b; -+ *context = lc; -+ return 0; -+ -+ bad: -+ kfree(lc); -+ return -EINVAL; -+} -+ -+static void linear_dtr(struct dm_table *t, void *c) -+{ -+ struct linear_c *lc = (struct linear_c *) c; -+ -+ dm_table_put_device(t, lc->dev); -+ kfree(c); -+} -+ -+static int linear_map(struct buffer_head *bh, int rw, void *context) -+{ -+ struct linear_c *lc = (struct linear_c *) context; -+ -+ bh->b_rdev = lc->dev->dev; -+ bh->b_rsector = bh->b_rsector + lc->delta; -+ -+ return 1; -+} -+ -+static struct target_type linear_target = { -+ name: "linear", -+ module: THIS_MODULE, -+ ctr: linear_ctr, -+ dtr: linear_dtr, -+ map: linear_map, -+}; -+ -+int __init dm_linear_init(void) -+{ -+ int r = dm_register_target(&linear_target); -+ -+ if (r < 0) -+ DMERR("linear: register failed %d", r); -+ -+ return r; -+} -+ -+void dm_linear_exit(void) -+{ -+ int r = dm_unregister_target(&linear_target); -+ -+ if (r < 0) -+ DMERR("linear: unregister failed %d", r); -+} -+ -diff -ruN linux-2.4.18/drivers/md/dm-mirror.c linux/drivers/md/dm-mirror.c ---- linux-2.4.18/drivers/md/dm-mirror.c Thu Jan 1 01:00:00 1970 -+++ linux/drivers/md/dm-mirror.c Tue Apr 23 22:13:47 2002 -@@ -0,0 +1,299 @@ -+/* -+ * Copyright (C) 2002 Sistina Software (UK) Limited. -+ * -+ * This file is released under the GPL. -+ */ -+ -+#include "dm.h" -+#include "kcopyd.h" -+ -+#include -+#include -+#include -+ -+/* kcopyd priority of mirror operations */ -+#define MIRROR_COPY_PRIORITY 5 -+ -+static kmem_cache_t *bh_cachep; -+ -+/* -+ * Mirror: maps a mirror range of a device. -+ */ -+struct mirror_c { -+ struct dm_dev *fromdev; -+ struct dm_dev *todev; -+ -+ unsigned long from_delta; -+ unsigned long to_delta; -+ -+ unsigned long frompos; -+ unsigned long topos; -+ -+ unsigned long got_to; -+ struct rw_semaphore lock; -+ struct buffer_head *bhstring; -+ int error; -+}; -+ -+/* Called when a duplicating I/O has finished */ -+static void mirror_end_io(struct buffer_head *bh, int uptodate) -+{ -+ struct mirror_c *lc = (struct mirror_c *) bh->b_private; -+ -+ /* Flag error if it failed */ -+ if (!uptodate) { -+ DMERR("Mirror copy to %s failed", kdevname(lc->todev->dev)); -+ lc->error = 1; -+ dm_notify(lc); /* TODO: interface ?? */ -+ } -+ kmem_cache_free(bh_cachep, bh); -+} -+ -+static void mirror_bh(struct mirror_c *mc, struct buffer_head *bh) -+{ -+ struct buffer_head *dbh = kmem_cache_alloc(bh_cachep, GFP_NOIO); -+ if (dbh) { -+ *dbh = *bh; -+ dbh->b_rdev = mc->todev->dev; -+ dbh->b_rsector = bh->b_rsector - mc->from_delta + mc->to_delta; -+ dbh->b_end_io = mirror_end_io; -+ dbh->b_private = mc; -+ -+ generic_make_request(WRITE, dbh); -+ } else { -+ DMERR("kmem_cache_alloc failed for mirror bh"); -+ mc->error = 1; -+ } -+} -+ -+/* Called when the copy I/O has finished */ -+static void copy_callback(copy_cb_reason_t reason, void *context, long arg) -+{ -+ struct mirror_c *lc = (struct mirror_c *) context; -+ struct buffer_head *bh; -+ -+ if (reason == COPY_CB_FAILED_READ || reason == COPY_CB_FAILED_WRITE) { -+ DMERR("Mirror block %s on %s failed, sector %ld", -+ reason == COPY_CB_FAILED_READ ? "read" : "write", -+ reason == COPY_CB_FAILED_READ ? -+ kdevname(lc->fromdev->dev) : -+ kdevname(lc->todev->dev), arg); -+ lc->error = 1; -+ return; -+ } -+ -+ if (reason == COPY_CB_COMPLETE) { -+ /* Say we've finished */ -+ dm_notify(lc); /* TODO: interface ?? */ -+ } -+ -+ if (reason == COPY_CB_PROGRESS) { -+ dm_notify(lc); /* TODO: interface ?? */ -+ } -+ -+ /* Submit, and mirror any pending BHs */ -+ down_write(&lc->lock); -+ lc->got_to = arg; -+ -+ bh = lc->bhstring; -+ lc->bhstring = NULL; -+ up_write(&lc->lock); -+ -+ while (bh) { -+ struct buffer_head *nextbh = bh->b_reqnext; -+ bh->b_reqnext = NULL; -+ generic_make_request(WRITE, bh); -+ mirror_bh(lc, bh); -+ bh = nextbh; -+ } -+} -+ -+/* -+ * Construct a mirror mapping: [] -+ */ -+static int mirror_ctr(struct dm_table *t, offset_t b, offset_t l, -+ int argc, char **argv, void **context) -+{ -+ struct mirror_c *lc; -+ unsigned long offset1, offset2; -+ char *value; -+ int priority = MIRROR_COPY_PRIORITY; -+ int throttle; -+ struct kcopyd_region src, dest; -+ -+ if (argc <= 4) { -+ *context = "dm-mirror: Not enough arguments"; -+ return -EINVAL; -+ } -+ -+ lc = kmalloc(sizeof(*lc), GFP_KERNEL); -+ if (lc == NULL) { -+ *context = "dm-mirror: Cannot allocate mirror context"; -+ return -ENOMEM; -+ } -+ -+ if (dm_table_get_device(t, argv[0], 0, l, &lc->fromdev)) { -+ *context = "dm-mirror: Device lookup failed"; -+ goto bad; -+ } -+ -+ offset1 = simple_strtoul(argv[1], &value, 10); -+ if (value == NULL) { -+ *context = "Invalid offset for dev1"; -+ dm_table_put_device(t, lc->fromdev); -+ goto bad; -+ } -+ -+ if (dm_table_get_device(t, argv[2], 0, l, &lc->todev)) { -+ *context = "dm-mirror: Device lookup failed"; -+ dm_table_put_device(t, lc->fromdev); -+ goto bad; -+ } -+ -+ offset2 = simple_strtoul(argv[3], &value, 10); -+ if (value == NULL) { -+ *context = "Invalid offset for dev2"; -+ goto bad_put; -+ } -+ -+ throttle = simple_strtoul(argv[4], &value, 10); -+ if (value == NULL) { -+ *context = "Invalid throttle value"; -+ goto bad_put; -+ } -+ -+ if (argc > 5) { -+ priority = simple_strtoul(argv[5], &value, 10); -+ if (value == NULL) { -+ *context = "Invalid priority value"; -+ goto bad_put; -+ } -+ } -+ -+ lc->from_delta = (int) offset1 - (int) b; -+ lc->to_delta = (int) offset2 - (int) b; -+ lc->frompos = offset1; -+ lc->topos = offset2; -+ lc->error = 0; -+ lc->bhstring = NULL; -+ init_rwsem(&lc->lock); -+ *context = lc; -+ -+ /* Tell kcopyd to do the biz */ -+ src.dev = lc->fromdev->dev; -+ src.sector = offset1; -+ src.count = l - offset1; -+ -+ dest.dev = lc->todev->dev; -+ dest.sector = offset2; -+ dest.count = l - offset1; -+ -+ if (kcopyd_copy(&src, &dest, priority, 0, copy_callback, lc)) { -+ DMERR("block copy call failed"); -+ dm_table_put_device(t, lc->fromdev); -+ dm_table_put_device(t, lc->todev); -+ goto bad; -+ } -+ return 0; -+ -+ bad_put: -+ dm_table_put_device(t, lc->fromdev); -+ dm_table_put_device(t, lc->todev); -+ bad: -+ kfree(lc); -+ return -EINVAL; -+} -+ -+static void mirror_dtr(struct dm_table *t, void *c) -+{ -+ struct mirror_c *lc = (struct mirror_c *) c; -+ -+ dm_table_put_device(t, lc->fromdev); -+ dm_table_put_device(t, lc->todev); -+ kfree(c); -+} -+ -+static int mirror_map(struct buffer_head *bh, int rw, void *context) -+{ -+ struct mirror_c *lc = (struct mirror_c *) context; -+ -+ bh->b_rdev = lc->fromdev->dev; -+ bh->b_rsector = bh->b_rsector + lc->from_delta; -+ -+ if (rw == WRITE) { -+ down_write(&lc->lock); -+ -+ /* -+ * If this area is in flight then save it until it's -+ * commited to the mirror disk and then submit it and -+ * its mirror. -+ */ -+ if (bh->b_rsector > lc->got_to && -+ bh->b_rsector <= lc->got_to + KIO_MAX_SECTORS) { -+ bh->b_reqnext = lc->bhstring; -+ lc->bhstring = bh; -+ up_write(&lc->lock); -+ return 0; -+ } -+ -+ /* -+ * If we've already copied this block then duplicate -+ * it to the mirror device -+ */ -+ if (bh->b_rsector < lc->got_to) { -+ /* Schedule copy of I/O to other target */ -+ mirror_bh(lc, bh); -+ } -+ up_write(&lc->lock); -+ } -+ return 1; -+} -+ -+static struct target_type mirror_target = { -+ name: "mirror", -+ module: THIS_MODULE, -+ ctr: mirror_ctr, -+ dtr: mirror_dtr, -+ map: mirror_map, -+}; -+ -+int __init dm_mirror_init(void) -+{ -+ int r; -+ -+ bh_cachep = kmem_cache_create("dm-mirror", -+ sizeof(struct buffer_head), -+ __alignof__(struct buffer_head), -+ 0, NULL, NULL); -+ if (!bh_cachep) { -+ return -1; -+ } -+ -+ r = dm_register_target(&mirror_target); -+ if (r < 0) { -+ DMERR("mirror: register failed %d", r); -+ kmem_cache_destroy(bh_cachep); -+ } -+ return r; -+} -+ -+void dm_mirror_exit(void) -+{ -+ int r = dm_unregister_target(&mirror_target); -+ -+ if (r < 0) -+ DMERR("mirror: unregister failed %d", r); -+ -+ kmem_cache_destroy(bh_cachep); -+} -+ -+/* -+ * Overrides for Emacs so that we follow Linus's tabbing style. -+ * Emacs will notice this stuff at the end of the file and automatically -+ * adjust the settings for this buffer only. This must remain at the end -+ * of the file. -+ * --------------------------------------------------------------------------- -+ * Local variables: -+ * c-file-style: "linux" -+ * End: -+ */ -diff -ruN linux-2.4.18/drivers/md/dm-snapshot.c linux/drivers/md/dm-snapshot.c ---- linux-2.4.18/drivers/md/dm-snapshot.c Thu Jan 1 01:00:00 1970 -+++ linux/drivers/md/dm-snapshot.c Tue Apr 23 22:07:45 2002 -@@ -0,0 +1,1080 @@ -+/* -+ * dm-snapshot.c -+ * -+ * Copyright (C) 2001-2002 Sistina Software (UK) Limited. -+ * -+ * This file is released under the GPL. -+ */ -+ -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+ -+#include "dm-snapshot.h" -+#include "kcopyd.h" -+ -+/* -+ * FIXME: Remove this before release. -+ */ -+#if 0 -+#define DMDEBUG(x...) DMWARN( ## x) -+#else -+#define DMDEBUG(x...) -+#endif -+ -+/* -+ * Hard sector size used all over the kernel -+ */ -+#define SECTOR_SIZE 512 -+ -+/* -+ * kcopyd priority of snapshot operations -+ */ -+#define SNAPSHOT_COPY_PRIORITY 2 -+ -+struct pending_exception { -+ struct exception e; -+ -+ /* -+ * Origin buffers waiting for this to complete are held -+ * in a list (using b_reqnext). -+ */ -+ struct buffer_head *origin_bhs; -+ struct buffer_head *snapshot_bhs; -+ -+ /* -+ * Other pending_exceptions that are processing this -+ * chunk. When this list is empty, we know we can -+ * complete the origins. -+ */ -+ struct list_head siblings; -+ -+ /* Pointer back to snapshot context */ -+ struct dm_snapshot *snap; -+ -+ /* -+ * 1 indicates the exception has already been sent to -+ * kcopyd. -+ */ -+ int started; -+}; -+ -+/* -+ * Hash table mapping origin volumes to lists of snapshots and -+ * a lock to protect it -+ */ -+static kmem_cache_t *exception_cache; -+static kmem_cache_t *pending_cache; -+static mempool_t *pending_pool; -+ -+/* -+ * One of these per registered origin, held in the snapshot_origins hash -+ */ -+struct origin { -+ /* The origin device */ -+ kdev_t dev; -+ -+ struct list_head hash_list; -+ -+ /* List of snapshots for this origin */ -+ struct list_head snapshots; -+}; -+ -+/* -+ * Useful macro for running the store functions. Use -+ * store_int_fn if you want the return value. -+ */ -+#define store_fn(snap, fn, args...) \ -+ if ((snap)->store. ## fn) \ -+ (snap)->store. ## fn ( &(snap)->store , ## args ) -+ -+#define store_int_fn(snap, fn, args...) \ -+ (((snap)->store. ## fn) ? \ -+ ((snap)->store. ## fn ( &(snap)->store , ## args )) : 0) -+ -+/* -+ * Size of the hash table for origin volumes. If we make this -+ * the size of the minors list then it should be nearly perfect -+ */ -+#define ORIGIN_HASH_SIZE 256 -+#define ORIGIN_MASK 0xFF -+static struct list_head *_origins; -+static struct rw_semaphore _origins_lock; -+ -+static int init_origin_hash(void) -+{ -+ int i; -+ -+ _origins = kmalloc(ORIGIN_HASH_SIZE * sizeof(struct list_head), -+ GFP_KERNEL); -+ if (!_origins) { -+ DMERR("Device mapper: Snapshot: unable to allocate memory"); -+ return -ENOMEM; -+ } -+ -+ for (i = 0; i < ORIGIN_HASH_SIZE; i++) -+ INIT_LIST_HEAD(_origins + i); -+ init_rwsem(&_origins_lock); -+ -+ return 0; -+} -+ -+static void exit_origin_hash(void) -+{ -+ kfree(_origins); -+} -+ -+static inline unsigned int origin_hash(kdev_t dev) -+{ -+ return MINOR(dev) & ORIGIN_MASK; -+} -+ -+static struct origin *__lookup_origin(kdev_t origin) -+{ -+ struct list_head *slist; -+ struct list_head *ol; -+ struct origin *o; -+ -+ ol = &_origins[origin_hash(origin)]; -+ list_for_each(slist, ol) { -+ o = list_entry(slist, struct origin, hash_list); -+ -+ if (o->dev == origin) -+ return o; -+ } -+ -+ return NULL; -+} -+ -+static void __insert_origin(struct origin *o) -+{ -+ struct list_head *sl = &_origins[origin_hash(o->dev)]; -+ list_add_tail(&o->hash_list, sl); -+} -+ -+/* -+ * Make a note of the snapshot and its origin so we can look it -+ * up when the origin has a write on it. -+ */ -+static int register_snapshot(struct dm_snapshot *snap) -+{ -+ struct origin *o; -+ kdev_t dev = snap->origin->dev; -+ -+ down_write(&_origins_lock); -+ o = __lookup_origin(dev); -+ -+ if (!o) { -+ /* New origin */ -+ o = kmalloc(sizeof(*o), GFP_KERNEL); -+ if (!o) { -+ up_write(&_origins_lock); -+ return -ENOMEM; -+ } -+ -+ /* Initialise the struct */ -+ INIT_LIST_HEAD(&o->snapshots); -+ o->dev = dev; -+ -+ __insert_origin(o); -+ } -+ -+ list_add_tail(&snap->list, &o->snapshots); -+ -+ up_write(&_origins_lock); -+ return 0; -+} -+ -+static void unregister_snapshot(struct dm_snapshot *s) -+{ -+ struct origin *o; -+ -+ down_write(&_origins_lock); -+ o = __lookup_origin(s->origin->dev); -+ -+ list_del(&s->list); -+ if (list_empty(&o->snapshots)) { -+ list_del(&o->hash_list); -+ kfree(o); -+ } -+ -+ up_write(&_origins_lock); -+} -+ -+/* -+ * Implementation of the exception hash tables. -+ */ -+static int init_exception_table(struct exception_table *et, uint32_t size) -+{ -+ int i; -+ -+ et->hash_mask = size - 1; -+ et->table = vmalloc(sizeof(struct list_head) * (size)); -+ if (!et->table) -+ return -ENOMEM; -+ -+ for (i = 0; i < size; i++) -+ INIT_LIST_HEAD(et->table + i); -+ -+ return 0; -+} -+ -+static void exit_exception_table(struct exception_table *et, kmem_cache_t * mem) -+{ -+ struct list_head *slot, *entry, *temp; -+ struct exception *ex; -+ int i, size; -+ -+ size = et->hash_mask + 1; -+ for (i = 0; i < size; i++) { -+ slot = et->table + i; -+ -+ list_for_each_safe(entry, temp, slot) { -+ ex = list_entry(entry, struct exception, hash_list); -+ kmem_cache_free(mem, ex); -+ } -+ } -+ -+ vfree(et->table); -+} -+ -+/* -+ * FIXME: check how this hash fn is performing. -+ */ -+static inline uint32_t exception_hash(struct exception_table *et, chunk_t chunk) -+{ -+ return chunk & et->hash_mask; -+} -+ -+static void insert_exception(struct exception_table *eh, struct exception *e) -+{ -+ struct list_head *l = &eh->table[exception_hash(eh, e->old_chunk)]; -+ list_add(&e->hash_list, l); -+} -+ -+static inline void remove_exception(struct exception *e) -+{ -+ list_del(&e->hash_list); -+} -+ -+/* -+ * Return the exception data for a sector, or NULL if not -+ * remapped. -+ */ -+static struct exception *lookup_exception(struct exception_table *et, -+ chunk_t chunk) -+{ -+ struct list_head *slot, *el; -+ struct exception *e; -+ -+ slot = &et->table[exception_hash(et, chunk)]; -+ list_for_each(el, slot) { -+ e = list_entry(el, struct exception, hash_list); -+ if (e->old_chunk == chunk) -+ return e; -+ } -+ -+ return NULL; -+} -+ -+static inline struct exception *alloc_exception(void) -+{ -+ return kmem_cache_alloc(exception_cache, GFP_NOIO); -+} -+ -+static inline void free_exception(struct exception *e) -+{ -+ kmem_cache_free(exception_cache, e); -+} -+ -+static inline struct pending_exception *alloc_pending_exception(void) -+{ -+ return mempool_alloc(pending_pool, GFP_NOIO); -+} -+ -+static inline void free_pending_exception(struct pending_exception *pe) -+{ -+ mempool_free(pe, pending_pool); -+} -+ -+int dm_add_exception(struct dm_snapshot *s, chunk_t old, chunk_t new) -+{ -+ struct exception *e; -+ -+ e = alloc_exception(); -+ if (!e) -+ return -ENOMEM; -+ -+ e->old_chunk = old; -+ e->new_chunk = new; -+ insert_exception(&s->complete, e); -+ return 0; -+} -+ -+/* -+ * Hard coded magic. -+ */ -+static int calc_max_buckets(void) -+{ -+ unsigned long mem; -+ -+ mem = num_physpages << PAGE_SHIFT; -+ mem /= 50; -+ mem /= sizeof(struct list_head); -+ -+ return mem; -+} -+ -+/* -+ * Rounds a number down to a power of 2. -+ */ -+static inline uint32_t round_down(uint32_t n) -+{ -+ while (n & (n - 1)) -+ n &= (n - 1); -+ return n; -+} -+ -+/* -+ * Allocate room for a suitable hash table. -+ */ -+static int init_hash_tables(struct dm_snapshot *s) -+{ -+ offset_t hash_size, cow_dev_size, origin_dev_size, max_buckets; -+ -+ /* -+ * Calculate based on the size of the original volume or -+ * the COW volume... -+ */ -+ cow_dev_size = get_dev_size(s->cow->dev); -+ origin_dev_size = get_dev_size(s->origin->dev); -+ max_buckets = calc_max_buckets(); -+ -+ hash_size = min(origin_dev_size, cow_dev_size) / s->chunk_size; -+ hash_size = min(hash_size, max_buckets); -+ -+ /* Round it down to a power of 2 */ -+ hash_size = round_down(hash_size); -+ if (init_exception_table(&s->complete, hash_size)) -+ return -ENOMEM; -+ -+ /* -+ * Allocate hash table for in-flight exceptions -+ * Make this smaller than the real hash table -+ */ -+ hash_size >>= 3; -+ if (!hash_size) -+ hash_size = 64; -+ -+ if (init_exception_table(&s->pending, hash_size)) { -+ exit_exception_table(&s->complete, exception_cache); -+ return -ENOMEM; -+ } -+ -+ return 0; -+} -+ -+/* -+ * Construct a snapshot mapping:

-+ * -+ */ -+static int snapshot_ctr(struct dm_table *t, offset_t b, offset_t l, -+ int argc, char **argv, void **context) -+{ -+ struct dm_snapshot *s; -+ unsigned long chunk_size; -+ unsigned long extent_size = 0L; -+ int r = -EINVAL; -+ char *persistent; -+ char *origin_path; -+ char *cow_path; -+ char *value; -+ int blocksize; -+ -+ if (argc < 4) { -+ *context = "dm-snapshot: Not enough arguments"; -+ r = -EINVAL; -+ goto bad; -+ } -+ -+ origin_path = argv[0]; -+ cow_path = argv[1]; -+ persistent = argv[2]; -+ -+ if ((*persistent & 0x5f) != 'P' && (*persistent & 0x5f) != 'N') { -+ *context = "Persistent flag is not P or N"; -+ r = -EINVAL; -+ goto bad; -+ } -+ -+ chunk_size = simple_strtoul(argv[3], &value, 10); -+ if (chunk_size == 0 || value == NULL) { -+ *context = "Invalid chunk size"; -+ r = -EINVAL; -+ goto bad; -+ } -+ -+ /* Get the extent size for persistent snapshots */ -+ if ((*persistent & 0x5f) == 'P') { -+ if (argc < 5) { -+ *context = "No extent size specified"; -+ r = -EINVAL; -+ goto bad; -+ } -+ -+ extent_size = simple_strtoul(argv[4], &value, 10); -+ if (extent_size == 0 || value == NULL) { -+ *context = "Invalid extent size"; -+ r = -EINVAL; -+ goto bad; -+ } -+ } -+ -+ s = kmalloc(sizeof(*s), GFP_KERNEL); -+ if (s == NULL) { -+ *context = "Cannot allocate snapshot context private structure"; -+ r = -ENOMEM; -+ goto bad; -+ } -+ -+ r = dm_table_get_device(t, origin_path, 0, 0, &s->origin); -+ if (r) { -+ *context = "Cannot get origin device"; -+ goto bad_free; -+ } -+ -+ r = dm_table_get_device(t, cow_path, 0, 0, &s->cow); -+ if (r) { -+ dm_table_put_device(t, s->origin); -+ *context = "Cannot get COW device"; -+ goto bad_free; -+ } -+ -+ /* Validate the extent and chunk sizes against the device block size */ -+ blocksize = get_hardsect_size(s->cow->dev); -+ if (chunk_size % (blocksize / SECTOR_SIZE)) { -+ *context = "Chunk size is not a multiple of device blocksize"; -+ r = -EINVAL; -+ goto bad_putdev; -+ } -+ -+ if (extent_size % (blocksize / SECTOR_SIZE)) { -+ *context = "Extent size is not a multiple of device blocksize"; -+ r = -EINVAL; -+ goto bad_putdev; -+ } -+ -+ /* Check the sizes are small enough to fit in one kiovec */ -+ if (chunk_size > KIO_MAX_SECTORS) { -+ *context = "Chunk size is too big"; -+ r = -EINVAL; -+ goto bad_putdev; -+ } -+ -+ if (extent_size > KIO_MAX_SECTORS) { -+ *context = "Extent size is too big"; -+ r = -EINVAL; -+ goto bad_putdev; -+ } -+ -+ /* Check chunk_size is a power of 2 */ -+ if (chunk_size & (chunk_size - 1)) { -+ *context = "Chunk size is not a power of 2"; -+ r = -EINVAL; -+ goto bad_putdev; -+ } -+ -+ s->chunk_size = chunk_size; -+ s->chunk_mask = chunk_size - 1; -+ for (s->chunk_shift = 0; chunk_size; -+ s->chunk_shift++, chunk_size >>= 1) -+ ; -+ s->chunk_shift--; -+ -+ s->valid = 1; -+ init_rwsem(&s->lock); -+ -+ /* Allocate hash table for COW data */ -+ if (init_hash_tables(s)) { -+ *context = "Unable to allocate hash table space"; -+ r = -ENOMEM; -+ goto bad_putdev; -+ } -+ -+ /* -+ * Check the persistent flag - done here because we need the iobuf -+ * to check the LV header -+ */ -+#if 0 -+ if ((*persistent & 0x5f) == 'P') -+ r = dm_create_persistent(&s->store, s, blocksize, -+ extent_size, context); -+ else -+#endif -+ r = dm_create_transient(&s->store, s, blocksize, context); -+ -+ if (r) { -+ *context = "Couldn't create exception store"; -+ r = -EINVAL; -+ goto bad_free1; -+ } -+ -+ /* Allocate the COW iobuf and set associated variables */ -+ r = store_int_fn(s, init, blocksize, extent_size, context); -+ if (r) { -+ *context = "Couldn't initialise exception store"; -+ goto bad_free1; -+ } -+ -+ /* Flush IO to the origin device */ -+#if LVM_VFS_ENHANCEMENT -+ fsync_dev_lockfs(s->origin->dev); -+#else -+ fsync_dev(s->origin->dev); -+#endif -+ -+ /* Add snapshot to the list of snapshots for this origin */ -+ if (register_snapshot(s)) { -+ r = -EINVAL; -+ *context = "Cannot register snapshot origin"; -+ goto bad_free2; -+ } -+#if LVM_VFS_ENHANCEMENT -+ unlockfs(s->origin->dev); -+#endif -+ -+ *context = s; -+ return 0; -+ -+ bad_free2: -+ store_fn(s, destroy); -+ -+ bad_free1: -+ exit_exception_table(&s->pending, pending_cache); -+ exit_exception_table(&s->complete, exception_cache); -+ -+ bad_putdev: -+ dm_table_put_device(t, s->cow); -+ dm_table_put_device(t, s->origin); -+ -+ bad_free: -+ kfree(s); -+ -+ bad: -+ return r; -+} -+ -+static void snapshot_dtr(struct dm_table *t, void *context) -+{ -+ struct dm_snapshot *s = (struct dm_snapshot *) context; -+ -+ unregister_snapshot(s); -+ -+ exit_exception_table(&s->pending, pending_cache); -+ exit_exception_table(&s->complete, exception_cache); -+ -+ /* Deallocate memory used */ -+ store_fn(s, destroy); -+ -+ dm_table_put_device(t, s->origin); -+ dm_table_put_device(t, s->cow); -+ kfree(s); -+} -+ -+/* -+ * We hold lists of buffer_heads, using the b_reqnext field. -+ */ -+static void queue_buffer(struct buffer_head **queue, struct buffer_head *bh) -+{ -+ bh->b_reqnext = *queue; -+ *queue = bh; -+} -+ -+/* -+ * Flush a list of buffers. -+ */ -+static void flush_buffers(struct buffer_head *bh) -+{ -+ struct buffer_head *n; -+ -+ DMDEBUG("begin flush"); -+ while (bh) { -+ n = bh->b_reqnext; -+ bh->b_reqnext = NULL; -+ DMDEBUG("flushing %p", bh); -+ generic_make_request(WRITE, bh); -+ bh = n; -+ } -+ -+ run_task_queue(&tq_disk); -+} -+ -+/* -+ * Error a list of buffers. -+ */ -+static void error_buffers(struct buffer_head *bh) -+{ -+ struct buffer_head *n; -+ -+ while (bh) { -+ n = bh->b_reqnext; -+ bh->b_reqnext = NULL; -+ buffer_IO_error(bh); -+ bh = n; -+ } -+} -+ -+/* -+ * Called when the copy I/O has finished -+ */ -+static void copy_callback(int err, void *context) -+{ -+ struct pending_exception *pe = (struct pending_exception *) context; -+ struct dm_snapshot *s = pe->snap; -+ struct exception *e; -+ -+ if (!err) { -+ /* Update the metadata if we are persistent */ -+ store_fn(s, commit_exception, &pe->e); -+ -+ e = alloc_exception(); -+ if (!e) { -+ /* FIXME: what do we do now ? */ -+ return; -+ } -+ -+ /* -+ * Add a proper exception, and remove the -+ * inflight exception from the list. -+ */ -+ down_write(&pe->snap->lock); -+ -+ memcpy(e, &pe->e, sizeof(*e)); -+ insert_exception(&s->complete, e); -+ remove_exception(&pe->e); -+ -+ /* Submit any pending write BHs */ -+ up_write(&pe->snap->lock); -+ -+ flush_buffers(pe->snapshot_bhs); -+ DMDEBUG("Exception completed successfully."); -+ -+ } else { -+ /* Read/write error - snapshot is unusable */ -+ DMERR("Error reading/writing snapshot"); -+ -+ down_write(&pe->snap->lock); -+ store_fn(pe->snap, drop_snapshot); -+ pe->snap->valid = 0; -+ remove_exception(&pe->e); -+ up_write(&pe->snap->lock); -+ -+ error_buffers(pe->snapshot_bhs); -+ -+ DMDEBUG("Exception failed."); -+ } -+ -+ if (list_empty(&pe->siblings)) -+ flush_buffers(pe->origin_bhs); -+ else -+ list_del(&pe->siblings); -+ -+ free_pending_exception(pe); -+} -+ -+/* -+ * Dispatches the copy operation to kcopyd. -+ */ -+static inline void start_copy(struct pending_exception *pe) -+{ -+ struct dm_snapshot *s = pe->snap; -+ struct kcopyd_region src, dest; -+ -+ src.dev = s->origin->dev; -+ src.sector = chunk_to_sector(s, pe->e.old_chunk); -+ src.count = s->chunk_size; -+ -+ dest.dev = s->cow->dev; -+ dest.sector = chunk_to_sector(s, pe->e.new_chunk); -+ dest.count = s->chunk_size; -+ -+ if (!pe->started) { -+ /* Hand over to kcopyd */ -+ kcopyd_copy(&src, &dest, copy_callback, pe); -+ pe->started = 1; -+ } -+} -+ -+/* -+ * Looks to see if this snapshot already has a pending exception -+ * for this chunk, otherwise it allocates a new one and inserts -+ * it into the pending table. -+ */ -+static struct pending_exception *find_pending_exception(struct dm_snapshot *s, -+ struct buffer_head *bh) -+{ -+ struct exception *e; -+ struct pending_exception *pe; -+ chunk_t chunk = sector_to_chunk(s, bh->b_rsector); -+ -+ /* -+ * Is there a pending exception for this already ? -+ */ -+ e = lookup_exception(&s->pending, chunk); -+ if (e) { -+ /* cast the exception to a pending exception */ -+ pe = list_entry(e, struct pending_exception, e); -+ -+ } else { -+ /* Create a new pending exception */ -+ pe = alloc_pending_exception(); -+ if (!pe) { -+ DMWARN("Couldn't allocate pending exception."); -+ return NULL; -+ } -+ -+ pe->e.old_chunk = chunk; -+ pe->origin_bhs = pe->snapshot_bhs = NULL; -+ INIT_LIST_HEAD(&pe->siblings); -+ pe->snap = s; -+ pe->started = 0; -+ -+ if (store_int_fn(s, prepare_exception, &pe->e)) { -+ free_pending_exception(pe); -+ s->valid = 0; -+ return NULL; -+ } -+ -+ insert_exception(&s->pending, &pe->e); -+ } -+ -+ return pe; -+} -+ -+static inline void remap_exception(struct dm_snapshot *s, struct exception *e, -+ struct buffer_head *bh) -+{ -+ bh->b_rdev = s->cow->dev; -+ bh->b_rsector = chunk_to_sector(s, e->new_chunk) + -+ (bh->b_rsector & s->chunk_mask); -+} -+ -+static int snapshot_map(struct buffer_head *bh, int rw, void *context) -+{ -+ struct exception *e; -+ struct dm_snapshot *s = (struct dm_snapshot *) context; -+ int r = 1; -+ chunk_t chunk; -+ struct pending_exception *pe; -+ -+ chunk = sector_to_chunk(s, bh->b_rsector); -+ -+ /* Full snapshots are not usable */ -+ if (!s->valid) -+ return -1; -+ -+ /* -+ * Write to snapshot - higher level takes care of RW/RO -+ * flags so we should only get this if we are -+ * writeable. -+ */ -+ if (rw == WRITE) { -+ -+ down_write(&s->lock); -+ -+ /* If the block is already remapped - use that, else remap it */ -+ e = lookup_exception(&s->complete, chunk); -+ if (e) -+ remap_exception(s, e, bh); -+ -+ else { -+ pe = find_pending_exception(s, bh); -+ -+ if (!pe) { -+ store_fn(s, drop_snapshot); -+ s->valid = 0; -+ } -+ -+ queue_buffer(&pe->snapshot_bhs, bh); -+ start_copy(pe); -+ r = 0; -+ } -+ -+ up_write(&s->lock); -+ -+ } else { -+ /* -+ * FIXME: this read path scares me because we -+ * always use the origin when we have a pending -+ * exception. However I can't think of a -+ * situation where this is wrong - ejt. -+ */ -+ -+ /* Do reads */ -+ down_read(&s->lock); -+ -+ /* See if it it has been remapped */ -+ e = lookup_exception(&s->complete, chunk); -+ if (e) -+ remap_exception(s, e, bh); -+ else -+ bh->b_rdev = s->origin->dev; -+ -+ up_read(&s->lock); -+ } -+ -+ return r; -+} -+ -+static int __origin_write(struct list_head *snapshots, struct buffer_head *bh) -+{ -+ int r = 1; -+ struct list_head *sl; -+ struct dm_snapshot *snap; -+ struct exception *e; -+ struct pending_exception *pe, *last = NULL; -+ chunk_t chunk; -+ -+ /* Do all the snapshots on this origin */ -+ list_for_each(sl, snapshots) { -+ snap = list_entry(sl, struct dm_snapshot, list); -+ -+ /* Only deal with valid snapshots */ -+ if (!snap->valid) -+ continue; -+ -+ down_write(&snap->lock); -+ -+ /* -+ * Remember, different snapshots can have -+ * different chunk sizes. -+ */ -+ chunk = sector_to_chunk(snap, bh->b_rsector); -+ -+ /* -+ * Check exception table to see if block -+ * is already remapped in this snapshot -+ * and trigger an exception if not. -+ */ -+ e = lookup_exception(&snap->complete, chunk); -+ if (!e) { -+ pe = find_pending_exception(snap, bh); -+ if (!pe) { -+ store_fn(snap, drop_snapshot); -+ snap->valid = 0; -+ } else { -+ -+ if (last) -+ list_splice(&pe->siblings, -+ &last->siblings); -+ -+ last = pe; -+ r = 0; -+ } -+ } -+ -+ up_write(&snap->lock); -+ } -+ -+ /* -+ * Now that we have a complete pe list we can start the copying. -+ */ -+ if (last) { -+ pe = last; -+ do { -+ down_write(&pe->snap->lock); -+ queue_buffer(&pe->origin_bhs, bh); -+ start_copy(pe); -+ up_write(&pe->snap->lock); -+ pe = list_entry(pe->siblings.next, -+ struct pending_exception, siblings); -+ -+ } while (pe != last); -+ } -+ -+ return r; -+} -+ -+/* -+ * Called on a write from the origin driver. -+ */ -+int do_origin(struct dm_dev *origin, struct buffer_head *bh) -+{ -+ struct origin *o; -+ int r; -+ -+ down_read(&_origins_lock); -+ o = __lookup_origin(origin->dev); -+ if (!o) -+ BUG(); -+ -+ r = __origin_write(&o->snapshots, bh); -+ up_read(&_origins_lock); -+ -+ return r; -+} -+ -+/* -+ * Origin: maps a linear range of a device, with hooks for snapshotting. -+ */ -+ -+/* -+ * Construct an origin mapping: -+ * The context for an origin is merely a 'struct dm_dev *' -+ * pointing to the real device. -+ */ -+static int origin_ctr(struct dm_table *t, offset_t b, offset_t l, -+ int argc, char **argv, void **context) -+{ -+ int r; -+ struct dm_dev *dev; -+ -+ if (argc != 1) { -+ *context = "dm-origin: incorrect number of arguments"; -+ return -EINVAL; -+ } -+ -+ r = dm_table_get_device(t, argv[0], 0, l, &dev); -+ if (r) { -+ *context = "Cannot get target device"; -+ return r; -+ } -+ -+ *context = dev; -+ -+ return 0; -+} -+ -+static void origin_dtr(struct dm_table *t, void *c) -+{ -+ struct dm_dev *dev = (struct dm_dev *) c; -+ dm_table_put_device(t, dev); -+} -+ -+static int origin_map(struct buffer_head *bh, int rw, void *context) -+{ -+ struct dm_dev *dev = (struct dm_dev *) context; -+ bh->b_rdev = dev->dev; -+ -+ /* Only tell snapshots if this is a write */ -+ return (rw == WRITE) ? do_origin(dev, bh) : 1; -+} -+ -+static struct target_type origin_target = { -+ name: "snapshot-origin", -+ module: THIS_MODULE, -+ ctr: origin_ctr, -+ dtr: origin_dtr, -+ map: origin_map, -+ err: NULL -+}; -+ -+static struct target_type snapshot_target = { -+ name: "snapshot", -+ module: THIS_MODULE, -+ ctr: snapshot_ctr, -+ dtr: snapshot_dtr, -+ map: snapshot_map, -+ err: NULL -+}; -+ -+int __init dm_snapshot_init(void) -+{ -+ int r; -+ -+ r = dm_register_target(&snapshot_target); -+ if (r) { -+ DMERR("snapshot target register failed %d", r); -+ return r; -+ } -+ -+ r = dm_register_target(&origin_target); -+ if (r < 0) { -+ DMERR("Device mapper: Origin: register failed %d\n", r); -+ goto bad1; -+ } -+ -+ r = init_origin_hash(); -+ if (r) { -+ DMERR("init_origin_hash failed."); -+ goto bad2; -+ } -+ -+ exception_cache = kmem_cache_create("dm-snapshot-ex", -+ sizeof(struct exception), -+ __alignof__(struct exception), -+ 0, NULL, NULL); -+ if (!exception_cache) { -+ DMERR("Couldn't create exception cache."); -+ r = -ENOMEM; -+ goto bad3; -+ } -+ -+ pending_cache = -+ kmem_cache_create("dm-snapshot-in", -+ sizeof(struct pending_exception), -+ __alignof__(struct pending_exception), -+ 0, NULL, NULL); -+ if (!pending_cache) { -+ DMERR("Couldn't create pending cache."); -+ r = -ENOMEM; -+ goto bad4; -+ } -+ -+ pending_pool = mempool_create(128, mempool_alloc_slab, -+ mempool_free_slab, pending_cache); -+ if (!pending_pool) { -+ DMERR("Couldn't create pending pool."); -+ r = -ENOMEM; -+ goto bad5; -+ } -+ -+ return 0; -+ -+ bad5: -+ kmem_cache_destroy(pending_cache); -+ bad4: -+ kmem_cache_destroy(exception_cache); -+ bad3: -+ exit_origin_hash(); -+ bad2: -+ dm_unregister_target(&origin_target); -+ bad1: -+ dm_unregister_target(&snapshot_target); -+ return r; -+} -+ -+void dm_snapshot_exit(void) -+{ -+ int r; -+ -+ r = dm_unregister_target(&snapshot_target); -+ if (r) -+ DMERR("snapshot unregister failed %d", r); -+ -+ r = dm_unregister_target(&origin_target); -+ if (r) -+ DMERR("origin unregister failed %d", r); -+ -+ exit_origin_hash(); -+ mempool_destroy(pending_pool); -+ kmem_cache_destroy(pending_cache); -+ kmem_cache_destroy(exception_cache); -+} -+ -+/* -+ * Overrides for Emacs so that we follow Linus's tabbing style. -+ * Emacs will notice this stuff at the end of the file and automatically -+ * adjust the settings for this buffer only. This must remain at the end -+ * of the file. -+ * --------------------------------------------------------------------------- -+ * Local variables: -+ * c-file-style: "linux" -+ * End: -+ */ -diff -ruN linux-2.4.18/drivers/md/dm-snapshot.h linux/drivers/md/dm-snapshot.h ---- linux-2.4.18/drivers/md/dm-snapshot.h Thu Jan 1 01:00:00 1970 -+++ linux/drivers/md/dm-snapshot.h Tue Apr 23 22:23:32 2002 -@@ -0,0 +1,144 @@ -+/* -+ * dm-snapshot.c -+ * -+ * Copyright (C) 2001-2002 Sistina Software (UK) Limited. -+ * -+ * This file is released under the GPL. -+ */ -+ -+#ifndef DM_SNAPSHOT_H -+#define DM_SNAPSHOT_H -+ -+#include "dm.h" -+#include -+ -+struct exception_table { -+ uint32_t hash_mask; -+ struct list_head *table; -+}; -+ -+/* -+ * The snapshot code deals with largish chunks of the disk at a -+ * time. Typically 64k - 256k. -+ */ -+/* FIXME: can we get away with limiting these to a uint32_t ? */ -+typedef offset_t chunk_t; -+ -+/* -+ * An exception is used where an old chunk of data has been -+ * replaced by a new one. -+ */ -+struct exception { -+ struct list_head hash_list; -+ -+ chunk_t old_chunk; -+ chunk_t new_chunk; -+}; -+ -+/* -+ * Abstraction to handle the meta/layout of exception stores (the -+ * COW device). -+ */ -+struct exception_store { -+ -+ /* -+ * Destroys this object when you've finished with it. -+ */ -+ void (*destroy)(struct exception_store *store); -+ -+ /* -+ * Read the metadata and populate the snapshot. -+ */ -+ int (*init)(struct exception_store *store, -+ int blocksize, unsigned long extent_size, void **context); -+ -+ /* -+ * Find somewhere to store the next exception. -+ */ -+ int (*prepare_exception)(struct exception_store *store, -+ struct exception *e); -+ -+ /* -+ * Update the metadata with this exception. -+ */ -+ int (*commit_exception)(struct exception_store *store, -+ struct exception *e); -+ -+ /* -+ * The snapshot is invalid, note this in the metadata. -+ */ -+ void (*drop_snapshot)(struct exception_store *store); -+ -+ struct dm_snapshot *snap; -+ void *context; -+}; -+ -+struct dm_snapshot { -+ struct rw_semaphore lock; -+ -+ struct dm_dev *origin; -+ struct dm_dev *cow; -+ -+ /* List of snapshots per Origin */ -+ struct list_head list; -+ -+ /* Size of data blocks saved - must be a power of 2 */ -+ chunk_t chunk_size; -+ chunk_t chunk_mask; -+ chunk_t chunk_shift; -+ -+ /* You can't use a snapshot if this is 0 (e.g. if full) */ -+ int valid; -+ -+ struct exception_table pending; -+ struct exception_table complete; -+ -+ /* The on disk metadata handler */ -+ struct exception_store store; -+}; -+ -+/* -+ * Used by the exception stores to load exceptions hen -+ * initialising. -+ */ -+int dm_add_exception(struct dm_snapshot *s, chunk_t old, chunk_t new); -+ -+/* -+ * Constructor and destructor for the default persistent -+ * store. -+ */ -+int dm_create_persistent(struct exception_store *store, -+ struct dm_snapshot *s, -+ int blocksize, -+ offset_t extent_size, -+ void **error); -+ -+int dm_create_transient(struct exception_store *store, -+ struct dm_snapshot *s, -+ int blocksize, void **error); -+ -+/* -+ * Return the number of sectors in the device. -+ */ -+static inline offset_t get_dev_size(kdev_t dev) -+{ -+ int *sizes; -+ -+ sizes = blk_size[MAJOR(dev)]; -+ if (sizes) -+ return sizes[MINOR(dev)] << 1; -+ -+ return 0; -+} -+ -+static inline chunk_t sector_to_chunk(struct dm_snapshot *s, offset_t sector) -+{ -+ return (sector & ~s->chunk_mask) >> s->chunk_shift; -+} -+ -+static inline offset_t chunk_to_sector(struct dm_snapshot *s, chunk_t chunk) -+{ -+ return chunk << s->chunk_shift; -+} -+ -+#endif -diff -ruN linux-2.4.18/drivers/md/dm-stripe.c linux/drivers/md/dm-stripe.c ---- linux-2.4.18/drivers/md/dm-stripe.c Thu Jan 1 01:00:00 1970 -+++ linux/drivers/md/dm-stripe.c Thu Jan 31 17:50:20 2002 -@@ -0,0 +1,202 @@ -+/* -+ * Copyright (C) 2001 Sistina Software (UK) Limited. -+ * -+ * This file is released under the GPL. -+ */ -+ -+#include "dm.h" -+ -+#include -+#include -+#include -+ -+struct stripe { -+ struct dm_dev *dev; -+ offset_t physical_start; -+}; -+ -+struct stripe_c { -+ offset_t logical_start; -+ uint32_t stripes; -+ -+ /* The size of this target / num. stripes */ -+ uint32_t stripe_width; -+ -+ /* stripe chunk size */ -+ uint32_t chunk_shift; -+ offset_t chunk_mask; -+ -+ struct stripe stripe[0]; -+}; -+ -+static inline struct stripe_c *alloc_context(int stripes) -+{ -+ size_t len = sizeof(struct stripe_c) + -+ (sizeof(struct stripe) * stripes); -+ -+ return kmalloc(len, GFP_KERNEL); -+} -+ -+/* -+ * Parse a single pair -+ */ -+static int get_stripe(struct dm_table *t, struct stripe_c *sc, -+ int stripe, char **argv) -+{ -+ char *end; -+ unsigned long start; -+ -+ start = simple_strtoul(argv[1], &end, 10); -+ if (*end) -+ return -EINVAL; -+ -+ if (dm_table_get_device(t, argv[0], start, sc->stripe_width, -+ &sc->stripe[stripe].dev)) -+ return -ENXIO; -+ -+ sc->stripe[stripe].physical_start = start; -+ return 0; -+} -+ -+/* -+ * Construct a striped mapping. -+ * [ ]+ -+ */ -+static int stripe_ctr(struct dm_table *t, offset_t b, offset_t l, -+ int argc, char **argv, void **context) -+{ -+ struct stripe_c *sc; -+ uint32_t stripes; -+ uint32_t chunk_size; -+ char *end; -+ int r, i; -+ -+ if (argc < 2) { -+ *context = "dm-stripe: Not enough arguments"; -+ return -EINVAL; -+ } -+ -+ stripes = simple_strtoul(argv[0], &end, 10); -+ if (*end) { -+ *context = "dm-stripe: Invalid stripe count"; -+ return -EINVAL; -+ } -+ -+ chunk_size =simple_strtoul(argv[1], &end, 10); -+ if (*end) { -+ *context = "dm-stripe: Invalid chunk_size"; -+ return -EINVAL; -+ } -+ -+ if (l % stripes) { -+ *context = "dm-stripe: Target length not divisable by " -+ "number of stripes"; -+ return -EINVAL; -+ } -+ -+ sc = alloc_context(stripes); -+ if (!sc) { -+ *context = "dm-stripe: Memory allocation for striped context " -+ "failed"; -+ return -ENOMEM; -+ } -+ -+ sc->logical_start = b; -+ sc->stripes = stripes; -+ sc->stripe_width = l / stripes; -+ -+ /* -+ * chunk_size is a power of two -+ */ -+ if (!chunk_size || (chunk_size & (chunk_size - 1))) { -+ *context = "dm-stripe: Invalid chunk size"; -+ kfree(sc); -+ return -EINVAL; -+ } -+ -+ sc->chunk_mask = chunk_size - 1; -+ for (sc->chunk_shift = 0; chunk_size; sc->chunk_shift++) -+ chunk_size >>= 1; -+ sc->chunk_shift--; -+ -+ /* -+ * Get the stripe destinations. -+ */ -+ for (i = 0; i < stripes; i++) { -+ if (argc < 2) { -+ *context = "dm-stripe: Not enough destinations " -+ "specified"; -+ kfree(sc); -+ return -EINVAL; -+ } -+ -+ argv += 2; -+ -+ r = get_stripe(t, sc, i, argv); -+ if (r < 0) { -+ *context = "dm-stripe: Couldn't parse stripe " -+ "destination"; -+ while (i--) -+ dm_table_put_device(t, sc->stripe[i].dev); -+ kfree(sc); -+ return r; -+ } -+ } -+ -+ *context = sc; -+ return 0; -+} -+ -+static void stripe_dtr(struct dm_table *t, void *c) -+{ -+ unsigned int i; -+ struct stripe_c *sc = (struct stripe_c *) c; -+ -+ for (i = 0; i < sc->stripes; i++) -+ dm_table_put_device(t, sc->stripe[i].dev); -+ -+ kfree(sc); -+} -+ -+static int stripe_map(struct buffer_head *bh, int rw, void *context) -+{ -+ struct stripe_c *sc = (struct stripe_c *) context; -+ -+ offset_t offset = bh->b_rsector - sc->logical_start; -+ uint32_t chunk = (uint32_t) (offset >> sc->chunk_shift); -+ uint32_t stripe = chunk % sc->stripes; /* 32bit modulus */ -+ chunk = chunk / sc->stripes; -+ -+ bh->b_rdev = sc->stripe[stripe].dev->dev; -+ bh->b_rsector = sc->stripe[stripe].physical_start + -+ (chunk << sc->chunk_shift) + (offset & sc->chunk_mask); -+ return 1; -+} -+ -+static struct target_type stripe_target = { -+ name: "striped", -+ module: THIS_MODULE, -+ ctr: stripe_ctr, -+ dtr: stripe_dtr, -+ map: stripe_map, -+}; -+ -+int __init dm_stripe_init(void) -+{ -+ int r; -+ -+ r = dm_register_target(&stripe_target); -+ if (r < 0) -+ DMWARN("striped target registration failed"); -+ -+ return r; -+} -+ -+void dm_stripe_exit(void) -+{ -+ if (dm_unregister_target(&stripe_target)) -+ DMWARN("striped target unregistration failed"); -+ -+ return; -+} -+ -diff -ruN linux-2.4.18/drivers/md/dm-table.c linux/drivers/md/dm-table.c ---- linux-2.4.18/drivers/md/dm-table.c Thu Jan 1 01:00:00 1970 -+++ linux/drivers/md/dm-table.c Tue Apr 23 21:48:53 2002 -@@ -0,0 +1,404 @@ -+/* -+ * Copyright (C) 2001 Sistina Software (UK) Limited. -+ * -+ * This file is released under the GPL. -+ */ -+ -+#include "dm.h" -+ -+#include -+ -+/* ceiling(n / size) * size */ -+static inline unsigned long round_up(unsigned long n, unsigned long size) -+{ -+ unsigned long r = n % size; -+ return n + (r ? (size - r) : 0); -+} -+ -+/* ceiling(n / size) */ -+static inline unsigned long div_up(unsigned long n, unsigned long size) -+{ -+ return round_up(n, size) / size; -+} -+ -+/* similar to ceiling(log_size(n)) */ -+static uint int_log(unsigned long n, unsigned long base) -+{ -+ int result = 0; -+ -+ while (n > 1) { -+ n = div_up(n, base); -+ result++; -+ } -+ -+ return result; -+} -+ -+/* -+ * return the highest key that you could lookup -+ * from the n'th node on level l of the btree. -+ */ -+static offset_t high(struct dm_table *t, int l, int n) -+{ -+ for (; l < t->depth - 1; l++) -+ n = get_child(n, CHILDREN_PER_NODE - 1); -+ -+ if (n >= t->counts[l]) -+ return (offset_t) - 1; -+ -+ return get_node(t, l, n)[KEYS_PER_NODE - 1]; -+} -+ -+/* -+ * fills in a level of the btree based on the -+ * highs of the level below it. -+ */ -+static int setup_btree_index(int l, struct dm_table *t) -+{ -+ int n, k; -+ offset_t *node; -+ -+ for (n = 0; n < t->counts[l]; n++) { -+ node = get_node(t, l, n); -+ -+ for (k = 0; k < KEYS_PER_NODE; k++) -+ node[k] = high(t, l + 1, get_child(n, k)); -+ } -+ -+ return 0; -+} -+ -+/* -+ * highs, and targets are managed as dynamic -+ * arrays during a table load. -+ */ -+static int alloc_targets(struct dm_table *t, int num) -+{ -+ offset_t *n_highs; -+ struct target *n_targets; -+ int n = t->num_targets; -+ unsigned long size = (sizeof(struct target) + sizeof(offset_t)) * num; -+ -+ n_highs = (offset_t *) vmalloc(size); -+ if (!n_highs) -+ return -ENOMEM; -+ -+ memset(n_highs, 0, size); -+ -+ n_targets = (struct target *) (n_highs + num); -+ -+ if (n) { -+ memcpy(n_highs, t->highs, sizeof(*n_highs) * n); -+ memcpy(n_targets, t->targets, sizeof(*n_targets) * n); -+ } -+ -+ memset(n_highs + n, -1, sizeof(*n_highs) * (num - n)); -+ if (t->highs) -+ vfree(t->highs); -+ -+ t->num_allocated = num; -+ t->highs = n_highs; -+ t->targets = n_targets; -+ -+ return 0; -+} -+ -+int dm_table_create(struct dm_table **result) -+{ -+ struct dm_table *t = kmalloc(sizeof(struct dm_table), GFP_NOIO); -+ -+ if (!t) -+ return -ENOMEM; -+ -+ memset(t, 0, sizeof(*t)); -+ INIT_LIST_HEAD(&t->devices); -+ -+ /* allocate a single node's worth of targets to begin with */ -+ if (alloc_targets(t, KEYS_PER_NODE)) { -+ kfree(t); -+ t = NULL; -+ return -ENOMEM; -+ } -+ -+ *result = t; -+ return 0; -+} -+ -+static void free_devices(struct list_head *devices) -+{ -+ struct list_head *tmp, *next; -+ -+ for (tmp = devices->next; tmp != devices; tmp = next) { -+ struct dm_dev *dd = list_entry(tmp, struct dm_dev, list); -+ next = tmp->next; -+ kfree(dd); -+ } -+} -+ -+void dm_table_destroy(struct dm_table *t) -+{ -+ int i; -+ -+ /* free the indexes (see dm_table_complete) */ -+ if (t->depth >= 2) -+ vfree(t->index[t->depth - 2]); -+ -+ /* free the targets */ -+ for (i = 0; i < t->num_targets; i++) { -+ struct target *tgt = &t->targets[i]; -+ -+ dm_put_target_type(t->targets[i].type); -+ -+ if (tgt->type->dtr) -+ tgt->type->dtr(t, tgt->private); -+ } -+ -+ vfree(t->highs); -+ -+ /* free the device list */ -+ if (t->devices.next != &t->devices) { -+ DMWARN("devices still present during destroy: " -+ "dm_table_remove_device calls missing"); -+ -+ free_devices(&t->devices); -+ } -+ -+ kfree(t); -+} -+ -+/* -+ * Checks to see if we need to extend highs or targets. -+ */ -+static inline int check_space(struct dm_table *t) -+{ -+ if (t->num_targets >= t->num_allocated) -+ return alloc_targets(t, t->num_allocated * 2); -+ -+ return 0; -+} -+ -+/* -+ * Convert a device path to a kdev_t. -+ */ -+int lookup_device(const char *path, kdev_t *dev) -+{ -+ int r; -+ struct nameidata nd; -+ struct inode *inode; -+ -+ if (!path_init(path, LOOKUP_FOLLOW, &nd)) -+ return 0; -+ -+ if ((r = path_walk(path, &nd))) -+ goto bad; -+ -+ inode = nd.dentry->d_inode; -+ if (!inode) { -+ r = -ENOENT; -+ goto bad; -+ } -+ -+ if (!S_ISBLK(inode->i_mode)) { -+ r = -EINVAL; -+ goto bad; -+ } -+ -+ *dev = inode->i_rdev; -+ -+ bad: -+ path_release(&nd); -+ return r; -+} -+ -+/* -+ * See if we've already got a device in the list. -+ */ -+static struct dm_dev *find_device(struct list_head *l, kdev_t dev) -+{ -+ struct list_head *tmp; -+ -+ list_for_each(tmp, l) { -+ struct dm_dev *dd = list_entry(tmp, struct dm_dev, list); -+ if (dd->dev == dev) -+ return dd; -+ } -+ -+ return NULL; -+} -+ -+/* -+ * Open a device so we can use it as a map destination. -+ */ -+static int open_dev(struct dm_dev *d) -+{ -+ int err; -+ -+ if (d->bd) -+ BUG(); -+ -+ if (!(d->bd = bdget(kdev_t_to_nr(d->dev)))) -+ return -ENOMEM; -+ -+ if ((err = blkdev_get(d->bd, FMODE_READ | FMODE_WRITE, 0, BDEV_FILE))) -+ return err; -+ -+ return 0; -+} -+ -+/* -+ * Close a device that we've been using. -+ */ -+static void close_dev(struct dm_dev *d) -+{ -+ if (!d->bd) -+ return; -+ -+ blkdev_put(d->bd, BDEV_FILE); -+ d->bd = NULL; -+} -+ -+/* -+ * If possible (ie. blk_size[major] is set), this -+ * checks an area of a destination device is -+ * valid. -+ */ -+static int check_device_area(kdev_t dev, offset_t start, offset_t len) -+{ -+ int *sizes; -+ offset_t dev_size; -+ -+ if (!(sizes = blk_size[MAJOR(dev)]) || !(dev_size = sizes[MINOR(dev)])) -+ /* we don't know the device details, -+ * so give the benefit of the doubt */ -+ return 1; -+ -+ /* convert to 512-byte sectors */ -+ dev_size <<= 1; -+ -+ return ((start < dev_size) && (len <= (dev_size - start))); -+} -+ -+/* -+ * Add a device to the list, or just increment the usage count -+ * if it's already present. -+ */ -+int dm_table_get_device(struct dm_table *t, const char *path, -+ offset_t start, offset_t len, struct dm_dev **result) -+{ -+ int r; -+ kdev_t dev; -+ struct dm_dev *dd; -+ -+ /* convert the path to a device */ -+ if ((r = lookup_device(path, &dev))) -+ return r; -+ -+ dd = find_device(&t->devices, dev); -+ if (!dd) { -+ dd = kmalloc(sizeof(*dd), GFP_KERNEL); -+ if (!dd) -+ return -ENOMEM; -+ -+ dd->dev = dev; -+ dd->bd = NULL; -+ -+ if ((r = open_dev(dd))) { -+ kfree(dd); -+ return r; -+ } -+ -+ atomic_set(&dd->count, 0); -+ list_add(&dd->list, &t->devices); -+ } -+ atomic_inc(&dd->count); -+ -+ if (!check_device_area(dd->dev, start, len)) { -+ DMWARN("device %s too small for target", path); -+ dm_table_put_device(t, dd); -+ return -EINVAL; -+ } -+ -+ *result = dd; -+ -+ return 0; -+} -+ -+/* -+ * Decrement a devices use count and remove it if neccessary. -+ */ -+void dm_table_put_device(struct dm_table *t, struct dm_dev *dd) -+{ -+ if (atomic_dec_and_test(&dd->count)) { -+ close_dev(dd); -+ list_del(&dd->list); -+ kfree(dd); -+ } -+} -+ -+/* -+ * Adds a target to the map -+ */ -+int dm_table_add_target(struct dm_table *t, offset_t highs, -+ struct target_type *type, void *private) -+{ -+ int r, n; -+ -+ if ((r = check_space(t))) -+ return r; -+ -+ n = t->num_targets++; -+ t->highs[n] = highs; -+ t->targets[n].type = type; -+ t->targets[n].private = private; -+ -+ return 0; -+} -+ -+static int setup_indexes(struct dm_table *t) -+{ -+ int i, total = 0; -+ offset_t *indexes; -+ -+ /* allocate the space for *all* the indexes */ -+ for (i = t->depth - 2; i >= 0; i--) { -+ t->counts[i] = div_up(t->counts[i + 1], CHILDREN_PER_NODE); -+ total += t->counts[i]; -+ } -+ -+ indexes = (offset_t *) vmalloc((unsigned long)NODE_SIZE * total); -+ if (!indexes) -+ return -ENOMEM; -+ -+ /* set up internal nodes, bottom-up */ -+ for (i = t->depth - 2, total = 0; i >= 0; i--) { -+ t->index[i] = indexes; -+ indexes += (KEYS_PER_NODE * t->counts[i]); -+ setup_btree_index(i, t); -+ } -+ -+ return 0; -+} -+ -+/* -+ * Builds the btree to index the map -+ */ -+int dm_table_complete(struct dm_table *t) -+{ -+ int leaf_nodes, r = 0; -+ -+ /* how many indexes will the btree have ? */ -+ leaf_nodes = div_up(t->num_targets, KEYS_PER_NODE); -+ t->depth = 1 + int_log(leaf_nodes, CHILDREN_PER_NODE); -+ -+ /* leaf layer has already been set up */ -+ t->counts[t->depth - 1] = leaf_nodes; -+ t->index[t->depth - 1] = t->highs; -+ -+ if (t->depth >= 2) -+ r = setup_indexes(t); -+ -+ return r; -+} -+ -+EXPORT_SYMBOL(dm_table_get_device); -+EXPORT_SYMBOL(dm_table_put_device); -diff -ruN linux-2.4.18/drivers/md/dm-target.c linux/drivers/md/dm-target.c ---- linux-2.4.18/drivers/md/dm-target.c Thu Jan 1 01:00:00 1970 -+++ linux/drivers/md/dm-target.c Tue Jan 8 17:57:45 2002 -@@ -0,0 +1,241 @@ -+/* -+ * Copyright (C) 2001 Sistina Software (UK) Limited -+ * -+ * This file is released under the GPL. -+ */ -+ -+#include "dm.h" -+ -+#include -+ -+struct tt_internal { -+ struct target_type tt; -+ -+ struct list_head list; -+ long use; -+}; -+ -+static LIST_HEAD(_targets); -+static rwlock_t _lock = RW_LOCK_UNLOCKED; -+ -+#define DM_MOD_NAME_SIZE 32 -+ -+/* -+ * Destructively splits up the argument list to pass to ctr. -+ */ -+int split_args(int max, int *argc, char **argv, char *input) -+{ -+ char *start, *end = input, *out; -+ *argc = 0; -+ -+ while (1) { -+ start = end; -+ -+ /* Skip whitespace */ -+ while (*start && isspace(*start)) -+ start++; -+ -+ if (!*start) -+ break; /* success, we hit the end */ -+ -+ /* 'out' is used to remove any back-quotes */ -+ end = out = start; -+ while (*end) { -+ /* Everything apart from '\0' can be quoted */ -+ if (*end == '\\' && *(end + 1)) { -+ *out++ = *(end + 1); -+ end += 2; -+ continue; -+ } -+ -+ if (isspace(*end)) -+ break; /* end of token */ -+ -+ *out++ = *end++; -+ } -+ -+ /* have we already filled the array ? */ -+ if ((*argc + 1) > max) -+ return -EINVAL; -+ -+ /* we know this is whitespace */ -+ if (*end) -+ end++; -+ -+ /* terminate the string and put it in the array */ -+ *out = '\0'; -+ argv[*argc] = start; -+ (*argc)++; -+ } -+ -+ return 0; -+} -+ -+static inline struct tt_internal *__find_target_type(const char *name) -+{ -+ struct list_head *tih; -+ struct tt_internal *ti; -+ -+ list_for_each(tih, &_targets) { -+ ti = list_entry(tih, struct tt_internal, list); -+ -+ if (!strcmp(name, ti->tt.name)) -+ return ti; -+ } -+ -+ return NULL; -+} -+ -+static struct tt_internal *get_target_type(const char *name) -+{ -+ struct tt_internal *ti; -+ -+ read_lock(&_lock); -+ ti = __find_target_type(name); -+ -+ if (ti) { -+ if (ti->use == 0 && ti->tt.module) -+ __MOD_INC_USE_COUNT(ti->tt.module); -+ ti->use++; -+ } -+ read_unlock(&_lock); -+ -+ return ti; -+} -+ -+static void load_module(const char *name) -+{ -+ char module_name[DM_MOD_NAME_SIZE] = "dm-"; -+ -+ /* Length check for strcat() below */ -+ if (strlen(name) > (DM_MOD_NAME_SIZE - 4)) -+ return; -+ -+ strcat(module_name, name); -+ request_module(module_name); -+ -+ return; -+} -+ -+struct target_type *dm_get_target_type(const char *name) -+{ -+ struct tt_internal *ti = get_target_type(name); -+ -+ if (!ti) { -+ load_module(name); -+ ti = get_target_type(name); -+ } -+ -+ return ti ? &ti->tt : NULL; -+} -+ -+void dm_put_target_type(struct target_type *t) -+{ -+ struct tt_internal *ti = (struct tt_internal *) t; -+ -+ read_lock(&_lock); -+ if (--ti->use == 0 && ti->tt.module) -+ __MOD_DEC_USE_COUNT(ti->tt.module); -+ -+ if (ti->use < 0) -+ BUG(); -+ read_unlock(&_lock); -+ -+ return; -+} -+ -+static struct tt_internal *alloc_target(struct target_type *t) -+{ -+ struct tt_internal *ti = kmalloc(sizeof(*ti), GFP_KERNEL); -+ -+ if (ti) { -+ memset(ti, 0, sizeof(*ti)); -+ ti->tt = *t; -+ } -+ -+ return ti; -+} -+ -+int dm_register_target(struct target_type *t) -+{ -+ int rv = 0; -+ struct tt_internal *ti = alloc_target(t); -+ -+ if (!ti) -+ return -ENOMEM; -+ -+ write_lock(&_lock); -+ if (__find_target_type(t->name)) -+ rv = -EEXIST; -+ else -+ list_add(&ti->list, &_targets); -+ -+ write_unlock(&_lock); -+ return rv; -+} -+ -+int dm_unregister_target(struct target_type *t) -+{ -+ struct tt_internal *ti; -+ -+ write_lock(&_lock); -+ if (!(ti = __find_target_type(t->name))) { -+ write_unlock(&_lock); -+ return -EINVAL; -+ } -+ -+ if (ti->use) { -+ write_unlock(&_lock); -+ return -ETXTBSY; -+ } -+ -+ list_del(&ti->list); -+ kfree(ti); -+ -+ write_unlock(&_lock); -+ return 0; -+} -+ -+/* -+ * io-err: always fails an io, useful for bringing -+ * up LV's that have holes in them. -+ */ -+static int io_err_ctr(struct dm_table *t, offset_t b, offset_t l, -+ int argc, char **args, void **context) -+{ -+ *context = NULL; -+ return 0; -+} -+ -+static void io_err_dtr(struct dm_table *t, void *c) -+{ -+ /* empty */ -+ return; -+} -+ -+static int io_err_map(struct buffer_head *bh, int rw, void *context) -+{ -+ buffer_IO_error(bh); -+ return 0; -+} -+ -+static struct target_type error_target = { -+ name: "error", -+ ctr: io_err_ctr, -+ dtr: io_err_dtr, -+ map: io_err_map, -+}; -+ -+int dm_target_init(void) -+{ -+ return dm_register_target(&error_target); -+} -+ -+void dm_target_exit(void) -+{ -+ if (dm_unregister_target(&error_target)) -+ DMWARN("error target unregistration failed"); -+} -+ -+EXPORT_SYMBOL(dm_register_target); -+EXPORT_SYMBOL(dm_unregister_target); -diff -ruN linux-2.4.18/drivers/md/dm.c linux/drivers/md/dm.c ---- linux-2.4.18/drivers/md/dm.c Thu Jan 1 01:00:00 1970 -+++ linux/drivers/md/dm.c Tue Apr 23 22:38:53 2002 -@@ -0,0 +1,1154 @@ -+/* -+ * Copyright (C) 2001 Sistina Software (UK) Limited. -+ * -+ * This file is released under the GPL. -+ */ -+ -+#include "dm.h" -+#include "kcopyd.h" -+ -+#include -+#include -+ -+/* we only need this for the lv_bmap struct definition, not happy */ -+#include -+ -+#define DEFAULT_READ_AHEAD 64 -+ -+static const char *_name = DM_NAME; -+static const char *_version = "0.94.10-ioctl (2002-04-23)"; -+static const char *_email = "lvm-devel@lists.sistina.com"; -+ -+static int major = 0; -+static int _major = 0; -+ -+struct io_hook { -+ struct mapped_device *md; -+ struct target *target; -+ int rw; -+ -+ void (*end_io) (struct buffer_head * bh, int uptodate); -+ void *context; -+}; -+ -+static kmem_cache_t *_io_hook_cache; -+ -+static struct mapped_device *_devs[MAX_DEVICES]; -+static struct rw_semaphore _dev_locks[MAX_DEVICES]; -+ -+/* -+ * This lock is only held by dm_create and dm_set_name to avoid -+ * race conditions where someone else may create a device with -+ * the same name. -+ */ -+static spinlock_t _create_lock = SPIN_LOCK_UNLOCKED; -+ -+/* block device arrays */ -+static int _block_size[MAX_DEVICES]; -+static int _blksize_size[MAX_DEVICES]; -+static int _hardsect_size[MAX_DEVICES]; -+ -+static devfs_handle_t _dev_dir; -+ -+static int request(request_queue_t * q, int rw, struct buffer_head *bh); -+static int dm_user_bmap(struct inode *inode, struct lv_bmap *lvb); -+ -+/* -+ * Protect the mapped_devices referenced from _dev[] -+ */ -+struct mapped_device *dm_get_r(int minor) -+{ -+ struct mapped_device *md; -+ -+ if (minor >= MAX_DEVICES) -+ return NULL; -+ -+ down_read(_dev_locks + minor); -+ md = _devs[minor]; -+ if (!md) -+ up_read(_dev_locks + minor); -+ return md; -+} -+ -+struct mapped_device *dm_get_w(int minor) -+{ -+ struct mapped_device *md; -+ -+ if (minor >= MAX_DEVICES) -+ return NULL; -+ -+ down_write(_dev_locks + minor); -+ md = _devs[minor]; -+ if (!md) -+ up_write(_dev_locks + minor); -+ return md; -+} -+ -+static int namecmp(struct mapped_device *md, const char *name, int nametype) -+{ -+ switch (nametype) { -+ case DM_LOOKUP_BY_NAME: -+ return strcmp(md->name, name); -+ break; -+ -+ case DM_LOOKUP_BY_UUID: -+ if (!md->uuid) -+ return -1; /* never equal */ -+ -+ return strcmp(md->uuid, name); -+ break; -+ -+ default: -+ DMWARN("Unknown comparison type in namecmp: %d", nametype); -+ BUG(); -+ } -+ -+ return -1; -+} -+ -+/* -+ * The interface (eg, ioctl) will probably access the devices -+ * through these slow 'by name' locks, this needs improving at -+ * some point if people start playing with *large* numbers of dm -+ * devices. -+ */ -+struct mapped_device *dm_get_name_r(const char *name, int nametype) -+{ -+ int i; -+ struct mapped_device *md; -+ -+ for (i = 0; i < MAX_DEVICES; i++) { -+ md = dm_get_r(i); -+ if (md) { -+ if (!namecmp(md, name, nametype)) -+ return md; -+ -+ dm_put_r(md); -+ } -+ } -+ -+ return NULL; -+} -+ -+struct mapped_device *dm_get_name_w(const char *name, int nametype) -+{ -+ int i; -+ struct mapped_device *md; -+ -+ /* -+ * To avoid getting write locks on all the devices we try -+ * and promote a read lock to a write lock, this can -+ * fail, in which case we just start again. -+ */ -+ -+ restart: -+ for (i = 0; i < MAX_DEVICES; i++) { -+ md = dm_get_r(i); -+ if (!md) -+ continue; -+ -+ if (namecmp(md, name, nametype)) { -+ dm_put_r(md); -+ continue; -+ } -+ -+ /* found it */ -+ dm_put_r(md); -+ -+ md = dm_get_w(i); -+ if (!md) -+ goto restart; -+ -+ if (namecmp(md, name, nametype)) { -+ dm_put_w(md); -+ goto restart; -+ } -+ -+ return md; -+ } -+ -+ return NULL; -+} -+ -+void dm_put_r(struct mapped_device *md) -+{ -+ int minor = MINOR(md->dev); -+ -+ if (minor >= MAX_DEVICES) -+ return; -+ -+ up_read(_dev_locks + minor); -+} -+ -+void dm_put_w(struct mapped_device *md) -+{ -+ int minor = MINOR(md->dev); -+ -+ if (minor >= MAX_DEVICES) -+ return; -+ -+ up_write(_dev_locks + minor); -+} -+ -+/* -+ * Setup and tear down the driver -+ */ -+static __init void init_locks(void) -+{ -+ int i; -+ -+ for (i = 0; i < MAX_DEVICES; i++) -+ init_rwsem(_dev_locks + i); -+} -+ -+static __init int local_init(void) -+{ -+ int r; -+ -+ init_locks(); -+ -+ /* allocate a slab for the io-hooks */ -+ if (!_io_hook_cache && -+ !(_io_hook_cache = kmem_cache_create("dm io hooks", -+ sizeof(struct io_hook), -+ 0, 0, NULL, NULL))) -+ return -ENOMEM; -+ -+ _major = major; -+ r = devfs_register_blkdev(_major, _name, &dm_blk_dops); -+ if (r < 0) { -+ DMERR("register_blkdev failed"); -+ kmem_cache_destroy(_io_hook_cache); -+ return r; -+ } -+ -+ if (!_major) -+ _major = r; -+ -+ /* set up the arrays */ -+ read_ahead[_major] = DEFAULT_READ_AHEAD; -+ blk_size[_major] = _block_size; -+ blksize_size[_major] = _blksize_size; -+ hardsect_size[_major] = _hardsect_size; -+ -+ blk_queue_make_request(BLK_DEFAULT_QUEUE(_major), request); -+ -+ _dev_dir = devfs_mk_dir(0, DM_DIR, NULL); -+ -+ DMINFO("%s initialised: %s", _version, _email); -+ return 0; -+} -+ -+static void local_exit(void) -+{ -+ if (kmem_cache_destroy(_io_hook_cache)) -+ DMWARN("io_hooks still allocated during unregistration"); -+ _io_hook_cache = NULL; -+ -+ if (devfs_unregister_blkdev(_major, _name) < 0) -+ DMERR("devfs_unregister_blkdev failed"); -+ -+ read_ahead[_major] = 0; -+ blk_size[_major] = NULL; -+ blksize_size[_major] = NULL; -+ hardsect_size[_major] = NULL; -+ _major = 0; -+ -+ DMINFO("%s cleaned up", _version); -+} -+ -+/* -+ * We have a lot of init/exit functions, so it seems easier to -+ * store them in an array. The disposable macro 'xx' -+ * expands a prefix into a pair of function names. -+ */ -+static struct { -+ int (*init)(void); -+ void (*exit)(void); -+ -+} _inits[] = { -+#define xx(n) {n ## _init, n ## _exit}, -+ xx(local) -+ xx(dm_target) -+ xx(dm_linear) -+ xx(dm_stripe) -+ xx(kcopyd) -+ xx(dm_snapshot) -+ xx(dm_interface) -+#undef xx -+}; -+ -+static int __init dm_init(void) -+{ -+ const int count = sizeof(_inits) / sizeof(*_inits); -+ -+ int r, i; -+ -+ for (i = 0; i < count; i++) { -+ r = _inits[i].init(); -+ if (r) -+ goto bad; -+ } -+ -+ return 0; -+ -+ bad: -+ while (i--) -+ _inits[i].exit(); -+ -+ return r; -+} -+ -+static void __exit dm_exit(void) -+{ -+ int i = sizeof(_inits) / sizeof(*_inits); -+ -+ dm_destroy_all(); -+ while (i--) -+ _inits[i].exit(); -+} -+ -+/* -+ * Block device functions -+ */ -+static int dm_blk_open(struct inode *inode, struct file *file) -+{ -+ struct mapped_device *md; -+ -+ md = dm_get_w(MINOR(inode->i_rdev)); -+ if (!md) -+ return -ENXIO; -+ -+ md->use_count++; -+ dm_put_w(md); -+ -+ return 0; -+} -+ -+static int dm_blk_close(struct inode *inode, struct file *file) -+{ -+ struct mapped_device *md; -+ -+ md = dm_get_w(MINOR(inode->i_rdev)); -+ if (!md) -+ return -ENXIO; -+ -+ if (md->use_count < 1) -+ DMWARN("incorrect reference count found in mapped_device"); -+ -+ md->use_count--; -+ dm_put_w(md); -+ -+ return 0; -+} -+ -+/* In 512-byte units */ -+#define VOLUME_SIZE(minor) (_block_size[(minor)] << 1) -+ -+static int dm_blk_ioctl(struct inode *inode, struct file *file, -+ uint command, unsigned long a) -+{ -+ int minor = MINOR(inode->i_rdev); -+ long size; -+ -+ if (minor >= MAX_DEVICES) -+ return -ENXIO; -+ -+ switch (command) { -+ case BLKSSZGET: -+ case BLKBSZGET: -+ case BLKROGET: -+ case BLKROSET: -+ case BLKRASET: -+ case BLKRAGET: -+ case BLKFLSBUF: -+#if 0 /* Future stacking block device */ -+ case BLKELVSET: -+ case BLKELVGET: -+#endif -+ return blk_ioctl(inode->i_rdev, command, a); -+ break; -+ -+ case BLKGETSIZE: -+ size = VOLUME_SIZE(minor); -+ if (copy_to_user((void *) a, &size, sizeof(long))) -+ return -EFAULT; -+ break; -+ -+ case BLKGETSIZE64: -+ size = VOLUME_SIZE(minor); -+ if (put_user((u64) size, (u64 *) a)) -+ return -EFAULT; -+ break; -+ -+ case BLKRRPART: -+ return -EINVAL; -+ -+ case LV_BMAP: -+ return dm_user_bmap(inode, (struct lv_bmap *) a); -+ -+ default: -+ DMWARN("unknown block ioctl 0x%x", command); -+ return -EINVAL; -+ } -+ -+ return 0; -+} -+ -+static inline struct io_hook *alloc_io_hook(void) -+{ -+ return kmem_cache_alloc(_io_hook_cache, GFP_NOIO); -+} -+ -+static inline void free_io_hook(struct io_hook *ih) -+{ -+ kmem_cache_free(_io_hook_cache, ih); -+} -+ -+/* -+ * FIXME: We need to decide if deferred_io's need -+ * their own slab, I say no for now since they are -+ * only used when the device is suspended. -+ */ -+static inline struct deferred_io *alloc_deferred(void) -+{ -+ return kmalloc(sizeof(struct deferred_io), GFP_NOIO); -+} -+ -+static inline void free_deferred(struct deferred_io *di) -+{ -+ kfree(di); -+} -+ -+/* -+ * Call a target's optional error function if an I/O failed. -+ */ -+static inline int call_err_fn(struct io_hook *ih, struct buffer_head *bh) -+{ -+ dm_err_fn err = ih->target->type->err; -+ -+ if (err) -+ return err(bh, ih->rw, ih->target->private); -+ -+ return 0; -+} -+ -+/* -+ * bh->b_end_io routine that decrements the pending count -+ * and then calls the original bh->b_end_io fn. -+ */ -+static void dec_pending(struct buffer_head *bh, int uptodate) -+{ -+ struct io_hook *ih = bh->b_bdev_private; -+ -+ if (!uptodate && call_err_fn(ih, bh)) -+ return; -+ -+ if (atomic_dec_and_test(&ih->md->pending)) -+ /* nudge anyone waiting on suspend queue */ -+ wake_up(&ih->md->wait); -+ -+ bh->b_end_io = ih->end_io; -+ bh->b_bdev_private = ih->context; -+ free_io_hook(ih); -+ -+ bh->b_end_io(bh, uptodate); -+} -+ -+/* -+ * Add the bh to the list of deferred io. -+ */ -+static int queue_io(struct buffer_head *bh, int rw) -+{ -+ struct deferred_io *di = alloc_deferred(); -+ struct mapped_device *md; -+ -+ if (!di) -+ return -ENOMEM; -+ -+ md = dm_get_w(MINOR(bh->b_rdev)); -+ if (!md) { -+ free_deferred(di); -+ return -ENXIO; -+ } -+ -+ if (!md->suspended) { -+ dm_put_w(md); -+ free_deferred(di); -+ return 1; -+ } -+ -+ di->bh = bh; -+ di->rw = rw; -+ di->next = md->deferred; -+ md->deferred = di; -+ -+ dm_put_w(md); -+ -+ return 0; /* deferred successfully */ -+} -+ -+/* -+ * Do the bh mapping for a given leaf -+ */ -+static inline int __map_buffer(struct mapped_device *md, -+ struct buffer_head *bh, int rw, int leaf) -+{ -+ int r; -+ dm_map_fn fn; -+ void *context; -+ struct io_hook *ih = NULL; -+ struct target *ti = md->map->targets + leaf; -+ -+ fn = ti->type->map; -+ context = ti->private; -+ -+ ih = alloc_io_hook(); -+ -+ if (!ih) -+ return -1; -+ -+ ih->md = md; -+ ih->rw = rw; -+ ih->target = ti; -+ ih->end_io = bh->b_end_io; -+ ih->context = bh->b_bdev_private; -+ -+ r = fn(bh, rw, context); -+ -+ if (r > 0) { -+ /* hook the end io request fn */ -+ atomic_inc(&md->pending); -+ bh->b_end_io = dec_pending; -+ bh->b_bdev_private = ih; -+ -+ } else if (r == 0) -+ /* we don't need to hook */ -+ free_io_hook(ih); -+ -+ else if (r < 0) { -+ free_io_hook(ih); -+ return -1; -+ } -+ -+ return r; -+} -+ -+/* -+ * Search the btree for the correct target. -+ */ -+static inline int __find_node(struct dm_table *t, struct buffer_head *bh) -+{ -+ int l, n = 0, k = 0; -+ offset_t *node; -+ -+ for (l = 0; l < t->depth; l++) { -+ n = get_child(n, k); -+ node = get_node(t, l, n); -+ -+ for (k = 0; k < KEYS_PER_NODE; k++) -+ if (node[k] >= bh->b_rsector) -+ break; -+ } -+ -+ return (KEYS_PER_NODE * n) + k; -+} -+ -+static int request(request_queue_t * q, int rw, struct buffer_head *bh) -+{ -+ struct mapped_device *md; -+ int r, minor = MINOR(bh->b_rdev); -+ -+ md = dm_get_r(minor); -+ if (!md) { -+ buffer_IO_error(bh); -+ return 0; -+ } -+ -+ /* -+ * If we're suspended we have to queue -+ * this io for later. -+ */ -+ while (md->suspended) { -+ dm_put_r(md); -+ -+ if (rw == READA) -+ goto bad_no_lock; -+ -+ r = queue_io(bh, rw); -+ -+ if (r < 0) -+ goto bad_no_lock; -+ -+ else if (r == 0) -+ return 0; /* deferred successfully */ -+ -+ /* -+ * We're in a while loop, because someone could suspend -+ * before we get to the following read lock. -+ */ -+ md = dm_get_r(minor); -+ if (!md) { -+ buffer_IO_error(bh); -+ return 0; -+ } -+ } -+ -+ if ((r = __map_buffer(md, bh, rw, __find_node(md->map, bh))) < 0) -+ goto bad; -+ -+ dm_put_r(md); -+ return r; -+ -+ bad: -+ dm_put_r(md); -+ -+ bad_no_lock: -+ buffer_IO_error(bh); -+ return 0; -+} -+ -+static int check_dev_size(int minor, unsigned long block) -+{ -+ /* FIXME: check this */ -+ unsigned long max_sector = (_block_size[minor] << 1) + 1; -+ unsigned long sector = (block + 1) * (_blksize_size[minor] >> 9); -+ -+ return (sector > max_sector) ? 0 : 1; -+} -+ -+/* -+ * Creates a dummy buffer head and maps it (for lilo). -+ */ -+static int do_bmap(kdev_t dev, unsigned long block, -+ kdev_t * r_dev, unsigned long *r_block) -+{ -+ struct mapped_device *md; -+ struct buffer_head bh; -+ int minor = MINOR(dev), r; -+ struct target *t; -+ -+ md = dm_get_r(minor); -+ if (!md) -+ return -ENXIO; -+ -+ if (md->suspended) { -+ dm_put_r(md); -+ return -EPERM; -+ } -+ -+ if (!check_dev_size(minor, block)) { -+ dm_put_r(md); -+ return -EINVAL; -+ } -+ -+ /* setup dummy bh */ -+ memset(&bh, 0, sizeof(bh)); -+ bh.b_blocknr = block; -+ bh.b_dev = bh.b_rdev = dev; -+ bh.b_size = _blksize_size[minor]; -+ bh.b_rsector = block * (bh.b_size >> 9); -+ -+ /* find target */ -+ t = md->map->targets + __find_node(md->map, &bh); -+ -+ /* do the mapping */ -+ r = t->type->map(&bh, READ, t->private); -+ -+ *r_dev = bh.b_rdev; -+ *r_block = bh.b_rsector / (bh.b_size >> 9); -+ -+ dm_put_r(md); -+ return r; -+} -+ -+/* -+ * Marshals arguments and results between user and kernel space. -+ */ -+static int dm_user_bmap(struct inode *inode, struct lv_bmap *lvb) -+{ -+ unsigned long block, r_block; -+ kdev_t r_dev; -+ int r; -+ -+ if (get_user(block, &lvb->lv_block)) -+ return -EFAULT; -+ -+ if ((r = do_bmap(inode->i_rdev, block, &r_dev, &r_block))) -+ return r; -+ -+ if (put_user(kdev_t_to_nr(r_dev), &lvb->lv_dev) || -+ put_user(r_block, &lvb->lv_block)) -+ return -EFAULT; -+ -+ return 0; -+} -+ -+/* -+ * See if the device with a specific minor # is free. The write -+ * lock is held when it returns successfully. -+ */ -+static inline int specific_dev(int minor, struct mapped_device *md) -+{ -+ if (minor >= MAX_DEVICES) { -+ DMWARN("request for a mapped_device beyond MAX_DEVICES (%d)", -+ MAX_DEVICES); -+ return -1; -+ } -+ -+ down_write(_dev_locks + minor); -+ if (_devs[minor]) { -+ /* in use */ -+ up_write(_dev_locks + minor); -+ return -1; -+ } -+ -+ return minor; -+} -+ -+/* -+ * Find the first free device. Again the write lock is held on -+ * success. -+ */ -+static int any_old_dev(struct mapped_device *md) -+{ -+ int i; -+ -+ for (i = 0; i < MAX_DEVICES; i++) -+ if (specific_dev(i, md) != -1) -+ return i; -+ -+ return -1; -+} -+ -+/* -+ * Allocate and initialise a blank device. -+ * Caller must ensure uuid is null-terminated. -+ * Device is returned with a write lock held. -+ */ -+static struct mapped_device *alloc_dev(const char *name, const char *uuid, -+ int minor) -+{ -+ struct mapped_device *md = kmalloc(sizeof(*md), GFP_KERNEL); -+ int len; -+ -+ if (!md) { -+ DMWARN("unable to allocate device, out of memory."); -+ return NULL; -+ } -+ -+ memset(md, 0, sizeof(*md)); -+ -+ /* -+ * This grabs the write lock if it succeeds. -+ */ -+ minor = (minor < 0) ? any_old_dev(md) : specific_dev(minor, md); -+ if (minor < 0) { -+ kfree(md); -+ return NULL; -+ } -+ -+ md->dev = MKDEV(_major, minor); -+ md->suspended = 0; -+ -+ strncpy(md->name, name, sizeof(md->name) - 1); -+ md->name[sizeof(md->name) - 1] = '\0'; -+ -+ /* -+ * Copy in the uuid. -+ */ -+ if (uuid && *uuid) { -+ len = strlen(uuid) + 1; -+ if (!(md->uuid = kmalloc(len, GFP_KERNEL))) { -+ DMWARN("unable to allocate uuid - out of memory."); -+ kfree(md); -+ return NULL; -+ } -+ strcpy(md->uuid, uuid); -+ } -+ -+ init_waitqueue_head(&md->wait); -+ return md; -+} -+ -+static int __register_device(struct mapped_device *md) -+{ -+ md->devfs_entry = -+ devfs_register(_dev_dir, md->name, DEVFS_FL_CURRENT_OWNER, -+ MAJOR(md->dev), MINOR(md->dev), -+ S_IFBLK | S_IRUSR | S_IWUSR | S_IRGRP, -+ &dm_blk_dops, NULL); -+ -+ return 0; -+} -+ -+static int __unregister_device(struct mapped_device *md) -+{ -+ devfs_unregister(md->devfs_entry); -+ return 0; -+} -+ -+/* -+ * The hardsect size for a mapped device is the smallest hardsect size -+ * from the devices it maps onto. -+ */ -+static int __find_hardsect_size(struct list_head *devices) -+{ -+ int result = INT_MAX, size; -+ struct list_head *tmp; -+ -+ list_for_each(tmp, devices) { -+ struct dm_dev *dd = list_entry(tmp, struct dm_dev, list); -+ size = get_hardsect_size(dd->dev); -+ if (size < result) -+ result = size; -+ } -+ return result; -+} -+ -+/* -+ * Bind a table to the device. -+ */ -+static int __bind(struct mapped_device *md, struct dm_table *t) -+{ -+ int minor = MINOR(md->dev); -+ -+ md->map = t; -+ -+ if (!t->num_targets) { -+ _block_size[minor] = 0; -+ _blksize_size[minor] = BLOCK_SIZE; -+ _hardsect_size[minor] = 0; -+ return 0; -+ } -+ -+ /* in k */ -+ _block_size[minor] = (t->highs[t->num_targets - 1] + 1) >> 1; -+ -+ _blksize_size[minor] = BLOCK_SIZE; -+ _hardsect_size[minor] = __find_hardsect_size(&t->devices); -+ register_disk(NULL, md->dev, 1, &dm_blk_dops, _block_size[minor]); -+ -+ return 0; -+} -+ -+static void __unbind(struct mapped_device *md) -+{ -+ int minor = MINOR(md->dev); -+ -+ dm_table_destroy(md->map); -+ md->map = NULL; -+ -+ _block_size[minor] = 0; -+ _blksize_size[minor] = 0; -+ _hardsect_size[minor] = 0; -+} -+ -+static int check_name(const char *name) -+{ -+ struct mapped_device *md; -+ -+ if (strchr(name, '/') || strlen(name) > DM_NAME_LEN) { -+ DMWARN("invalid device name"); -+ return -1; -+ } -+ -+ md = dm_get_name_r(name, DM_LOOKUP_BY_NAME); -+ if (md) { -+ dm_put_r(md); -+ DMWARN("device name already in use"); -+ return -1; -+ } -+ -+ return 0; -+} -+ -+static int check_uuid(const char *uuid) -+{ -+ struct mapped_device *md; -+ -+ if (uuid) { -+ md = dm_get_name_r(uuid, DM_LOOKUP_BY_UUID); -+ if (md) { -+ dm_put_r(md); -+ DMWARN("device uuid already in use"); -+ return -1; -+ } -+ } -+ -+ return 0; -+} -+ -+/* -+ * Constructor for a new device. -+ */ -+int dm_create(const char *name, const char *uuid, int minor, int ro, -+ struct dm_table *table) -+{ -+ int r; -+ struct mapped_device *md; -+ -+ spin_lock(&_create_lock); -+ if (check_name(name) || check_uuid(uuid)) { -+ spin_unlock(&_create_lock); -+ return -EINVAL; -+ } -+ -+ md = alloc_dev(name, uuid, minor); -+ if (!md) { -+ spin_unlock(&_create_lock); -+ return -ENXIO; -+ } -+ minor = MINOR(md->dev); -+ _devs[minor] = md; -+ -+ r = __register_device(md); -+ if (r) -+ goto err; -+ -+ r = __bind(md, table); -+ if (r) -+ goto err; -+ -+ dm_set_ro(md, ro); -+ -+ spin_unlock(&_create_lock); -+ dm_put_w(md); -+ return 0; -+ -+ err: -+ _devs[minor] = NULL; -+ if (md->uuid) -+ kfree(md->uuid); -+ -+ dm_put_w(md); -+ kfree(md); -+ spin_unlock(&_create_lock); -+ return r; -+} -+ -+/* -+ * Renames the device. No lock held. -+ */ -+int dm_set_name(const char *name, int nametype, const char *newname) -+{ -+ int r; -+ struct mapped_device *md; -+ -+ spin_lock(&_create_lock); -+ if (check_name(newname) < 0) { -+ spin_unlock(&_create_lock); -+ return -EINVAL; -+ } -+ -+ md = dm_get_name_w(name, nametype); -+ if (!md) { -+ spin_unlock(&_create_lock); -+ return -ENXIO; -+ } -+ -+ r = __unregister_device(md); -+ if (r) -+ goto out; -+ -+ strcpy(md->name, newname); -+ r = __register_device(md); -+ -+ out: -+ dm_put_w(md); -+ spin_unlock(&_create_lock); -+ return r; -+} -+ -+/* -+ * Destructor for the device. You cannot destroy an open -+ * device. Write lock must be held before calling. -+ * Caller must dm_put_w(md) then kfree(md) if call was successful. -+ */ -+int dm_destroy(struct mapped_device *md) -+{ -+ int minor, r; -+ -+ if (md->use_count) -+ return -EPERM; -+ -+ r = __unregister_device(md); -+ if (r) -+ return r; -+ -+ minor = MINOR(md->dev); -+ _devs[minor] = NULL; -+ __unbind(md); -+ -+ if (md->uuid) -+ kfree(md->uuid); -+ -+ return 0; -+} -+ -+/* -+ * Destroy all devices - except open ones -+ */ -+void dm_destroy_all(void) -+{ -+ int i, some_destroyed, r; -+ struct mapped_device *md; -+ -+ do { -+ some_destroyed = 0; -+ for (i = 0; i < MAX_DEVICES; i++) { -+ md = dm_get_w(i); -+ if (!md) -+ continue; -+ -+ r = dm_destroy(md); -+ dm_put_w(md); -+ -+ if (!r) { -+ kfree(md); -+ some_destroyed = 1; -+ } -+ } -+ } while (some_destroyed); -+} -+ -+/* -+ * Sets or clears the read-only flag for the device. Write lock -+ * must be held. -+ */ -+void dm_set_ro(struct mapped_device *md, int ro) -+{ -+ md->read_only = ro; -+ set_device_ro(md->dev, ro); -+} -+ -+/* -+ * A target is notifying us of some event -+ */ -+void dm_notify(void *target) -+{ -+} -+ -+/* -+ * Requeue the deferred buffer_heads by calling generic_make_request. -+ */ -+static void flush_deferred_io(struct deferred_io *c) -+{ -+ struct deferred_io *n; -+ -+ while (c) { -+ n = c->next; -+ generic_make_request(c->rw, c->bh); -+ free_deferred(c); -+ c = n; -+ } -+} -+ -+/* -+ * Swap in a new table (destroying old one). Write lock must be -+ * held. -+ */ -+int dm_swap_table(struct mapped_device *md, struct dm_table *table) -+{ -+ int r; -+ -+ /* device must be suspended */ -+ if (!md->suspended) -+ return -EPERM; -+ -+ __unbind(md); -+ -+ r = __bind(md, table); -+ if (r) -+ return r; -+ -+ return 0; -+} -+ -+/* -+ * We need to be able to change a mapping table under a mounted -+ * filesystem. for example we might want to move some data in -+ * the background. Before the table can be swapped with -+ * dm_bind_table, dm_suspend must be called to flush any in -+ * flight buffer_heads and ensure that any further io gets -+ * deferred. Write lock must be held. -+ */ -+int dm_suspend(struct mapped_device *md) -+{ -+ int minor = MINOR(md->dev); -+ DECLARE_WAITQUEUE(wait, current); -+ -+ if (md->suspended) -+ return -EINVAL; -+ -+ md->suspended = 1; -+ dm_put_w(md); -+ -+ /* wait for all the pending io to flush */ -+ add_wait_queue(&md->wait, &wait); -+ current->state = TASK_UNINTERRUPTIBLE; -+ do { -+ md = dm_get_w(minor); -+ if (!md) { -+ /* Caller expects to free this lock. Yuck. */ -+ down_write(_dev_locks + minor); -+ return -ENXIO; -+ } -+ -+ if (!atomic_read(&md->pending)) -+ break; -+ -+ dm_put_w(md); -+ schedule(); -+ -+ } while (1); -+ -+ current->state = TASK_RUNNING; -+ remove_wait_queue(&md->wait, &wait); -+ -+ return 0; -+} -+ -+int dm_resume(struct mapped_device *md) -+{ -+ int minor = MINOR(md->dev); -+ struct deferred_io *def; -+ -+ if (!md->suspended || !md->map->num_targets) -+ return -EINVAL; -+ -+ md->suspended = 0; -+ def = md->deferred; -+ md->deferred = NULL; -+ -+ dm_put_w(md); -+ flush_deferred_io(def); -+ run_task_queue(&tq_disk); -+ -+ if (!dm_get_w(minor)) { -+ /* FIXME: yuck */ -+ down_write(_dev_locks + minor); -+ return -ENXIO; -+ } -+ -+ return 0; -+} -+ -+struct block_device_operations dm_blk_dops = { -+ open: dm_blk_open, -+ release: dm_blk_close, -+ ioctl: dm_blk_ioctl, -+ owner: THIS_MODULE -+}; -+ -+/* -+ * module hooks -+ */ -+module_init(dm_init); -+module_exit(dm_exit); -+ -+MODULE_PARM(major, "i"); -+MODULE_PARM_DESC(major, "The major number of the device mapper"); -+MODULE_DESCRIPTION(DM_NAME " driver"); -+MODULE_AUTHOR("Joe Thornber "); -+MODULE_LICENSE("GPL"); -diff -ruN linux-2.4.18/drivers/md/dm.h linux/drivers/md/dm.h ---- linux-2.4.18/drivers/md/dm.h Thu Jan 1 01:00:00 1970 -+++ linux/drivers/md/dm.h Tue Apr 23 22:23:30 2002 -@@ -0,0 +1,220 @@ -+/* -+ * Internal header file for device mapper -+ * -+ * Copyright (C) 2001 Sistina Software -+ * -+ * This file is released under the LGPL. -+ */ -+ -+#ifndef DM_INTERNAL_H -+#define DM_INTERNAL_H -+ -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+ -+#define DM_NAME "device-mapper" /* Name for messaging */ -+#define MAX_DEPTH 16 -+#define NODE_SIZE L1_CACHE_BYTES -+#define KEYS_PER_NODE (NODE_SIZE / sizeof(offset_t)) -+#define CHILDREN_PER_NODE (KEYS_PER_NODE + 1) -+#define MAX_ARGS 32 -+#define MAX_DEVICES 256 -+ -+/* -+ * List of devices that a metadevice uses and should open/close. -+ */ -+struct dm_dev { -+ atomic_t count; -+ struct list_head list; -+ -+ kdev_t dev; -+ struct block_device *bd; -+}; -+ -+/* -+ * I/O that had to be deferred while we were suspended -+ */ -+struct deferred_io { -+ int rw; -+ struct buffer_head *bh; -+ struct deferred_io *next; -+}; -+ -+/* -+ * Btree leaf - this does the actual mapping -+ */ -+struct target { -+ struct target_type *type; -+ void *private; -+}; -+ -+/* -+ * The btree -+ */ -+struct dm_table { -+ /* btree table */ -+ int depth; -+ int counts[MAX_DEPTH]; /* in nodes */ -+ offset_t *index[MAX_DEPTH]; -+ -+ int num_targets; -+ int num_allocated; -+ offset_t *highs; -+ struct target *targets; -+ -+ /* a list of devices used by this table */ -+ struct list_head devices; -+}; -+ -+/* -+ * The actual device struct -+ */ -+struct mapped_device { -+ kdev_t dev; -+ char name[DM_NAME_LEN]; -+ char *uuid; -+ -+ int use_count; -+ int suspended; -+ int read_only; -+ -+ /* a list of io's that arrived while we were suspended */ -+ atomic_t pending; -+ wait_queue_head_t wait; -+ struct deferred_io *deferred; -+ -+ struct dm_table *map; -+ -+ /* used by dm-fs.c */ -+ devfs_handle_t devfs_entry; -+}; -+ -+extern struct block_device_operations dm_blk_dops; -+ -+/* dm-target.c */ -+int dm_target_init(void); -+struct target_type *dm_get_target_type(const char *name); -+void dm_put_target_type(struct target_type *t); -+void dm_target_exit(void); -+ -+/* -+ * Destructively splits argument list to pass to ctr. -+ */ -+int split_args(int max, int *argc, char **argv, char *input); -+ -+/* dm.c */ -+struct mapped_device *dm_get_r(int minor); -+struct mapped_device *dm_get_w(int minor); -+ -+/* -+ * There are two ways to lookup a device. -+ */ -+enum { -+ DM_LOOKUP_BY_NAME, -+ DM_LOOKUP_BY_UUID -+}; -+ -+struct mapped_device *dm_get_name_r(const char *name, int nametype); -+struct mapped_device *dm_get_name_w(const char *name, int nametype); -+ -+void dm_put_r(struct mapped_device *md); -+void dm_put_w(struct mapped_device *md); -+ -+/* -+ * Call with no lock. -+ */ -+int dm_create(const char *name, const char *uuid, int minor, int ro, -+ struct dm_table *table); -+int dm_set_name(const char *name, int nametype, const char *newname); -+void dm_destroy_all(void); -+ -+/* -+ * You must have the write lock before calling the remaining md -+ * methods. -+ */ -+int dm_destroy(struct mapped_device *md); -+void dm_set_ro(struct mapped_device *md, int ro); -+ -+/* -+ * The device must be suspended before calling this method. -+ */ -+int dm_swap_table(struct mapped_device *md, struct dm_table *t); -+ -+/* -+ * A device can still be used while suspended, but I/O is deferred. -+ */ -+int dm_suspend(struct mapped_device *md); -+int dm_resume(struct mapped_device *md); -+ -+/* -+ * Event notification -+ */ -+void dm_notify(void *target); -+ -+/* dm-table.c */ -+int dm_table_create(struct dm_table **result); -+void dm_table_destroy(struct dm_table *t); -+ -+int dm_table_add_target(struct dm_table *t, offset_t highs, -+ struct target_type *type, void *private); -+int dm_table_complete(struct dm_table *t); -+ -+/* Snapshots */ -+int dm_snapshot_init(void); -+void dm_snapshot_exit(void); -+ -+/* dm-mirror.c */ -+int dm_mirror_init(void); -+void dm_mirror_exit(void); -+ -+#define DMWARN(f, x...) printk(KERN_WARNING DM_NAME ": " f "\n" , ## x) -+#define DMERR(f, x...) printk(KERN_ERR DM_NAME ": " f "\n" , ## x) -+#define DMINFO(f, x...) printk(KERN_INFO DM_NAME ": " f "\n" , ## x) -+ -+/* -+ * Calculate the index of the child node of the n'th node k'th key. -+ */ -+static inline int get_child(int n, int k) -+{ -+ return (n * CHILDREN_PER_NODE) + k; -+} -+ -+/* -+ * Return the n'th node of level l from table t. -+ */ -+static inline offset_t *get_node(struct dm_table *t, int l, int n) -+{ -+ return t->index[l] + (n * KEYS_PER_NODE); -+} -+ -+/* -+ * The device-mapper can be driven through one of two interfaces; -+ * ioctl or filesystem, depending which patch you have applied. -+ */ -+int __init dm_interface_init(void); -+void dm_interface_exit(void); -+ -+/* -+ * Targets for linear and striped mappings -+ */ -+ -+int dm_linear_init(void); -+void dm_linear_exit(void); -+ -+int dm_stripe_init(void); -+void dm_stripe_exit(void); -+ -+#endif -diff -ruN linux-2.4.18/drivers/md/kcopyd.c linux/drivers/md/kcopyd.c ---- linux-2.4.18/drivers/md/kcopyd.c Thu Jan 1 01:00:00 1970 -+++ linux/drivers/md/kcopyd.c Tue Apr 23 22:28:13 2002 -@@ -0,0 +1,779 @@ -+/* -+ * Copyright (C) 2002 Sistina Software (UK) Limited. -+ * -+ * This file is released under the GPL. -+ */ -+ -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+ -+#include "kcopyd.h" -+ -+/* FIXME: this is only needed for the DMERR macros */ -+#include "dm.h" -+ -+/* -+ * Hard sector size used all over the kernel. -+ */ -+#define SECTOR_SIZE 512 -+#define SECTOR_SHIFT 9 -+static int wake_kcopyd(void); -+ -+/*----------------------------------------------------------------- -+ * We reserve our own pool of preallocated pages that are -+ * only used for kcopyd io. -+ *---------------------------------------------------------------*/ -+ -+/* -+ * FIXME: This should be configurable. -+ */ -+#define NUM_PAGES 512 -+ -+static DECLARE_MUTEX(_pages_lock); -+static int _num_free_pages; -+static struct page *_pages_array[NUM_PAGES]; -+ -+static __init int init_pages(void) -+{ -+ int i; -+ struct page *p; -+ -+ for (i = 0; i < NUM_PAGES; i++) { -+ p = alloc_page(GFP_KERNEL); -+ if (!p) -+ goto bad; -+ -+ LockPage(p); -+ _pages_array[i] = p; -+ } -+ -+ _num_free_pages = NUM_PAGES; -+ return 0; -+ -+ bad: -+ while (i--) -+ __free_page(_pages_array[i]); -+ return -ENOMEM; -+} -+ -+static void exit_pages(void) -+{ -+ int i; -+ struct page *p; -+ -+ for (i = 0; i < NUM_PAGES; i++) { -+ p = _pages_array[i]; -+ UnlockPage(p); -+ __free_page(p); -+ } -+ -+ _num_free_pages = 0; -+} -+ -+static int kcopyd_get_pages(int num, struct page **result) -+{ -+ int i; -+ -+ down(&_pages_lock); -+ if (_num_free_pages < num) { -+ up(&_pages_lock); -+ return -ENOMEM; -+ } -+ -+ for (i = 0; i < num; i++) { -+ _num_free_pages--; -+ result[i] = _pages_array[_num_free_pages]; -+ } -+ up(&_pages_lock); -+ -+ return 0; -+} -+ -+static void kcopyd_free_pages(int num, struct page **result) -+{ -+ int i; -+ -+ down(&_pages_lock); -+ for (i = 0; i < num; i++) -+ _pages_array[_num_free_pages++] = result[i]; -+ up(&_pages_lock); -+} -+ -+/*----------------------------------------------------------------- -+ * We keep our own private pool of buffer_heads. These are just -+ * held in a list on the b_reqnext field. -+ *---------------------------------------------------------------*/ -+ -+/* -+ * Make sure we have enough buffers to always keep the pages -+ * occupied. So we assume the worst case scenario where blocks -+ * are the size of a single sector. -+ */ -+#define NUM_BUFFERS NUM_PAGES * (PAGE_SIZE / SECTOR_SIZE) -+ -+static spinlock_t _buffer_lock = SPIN_LOCK_UNLOCKED; -+static struct buffer_head *_all_buffers; -+static struct buffer_head *_free_buffers; -+ -+static __init int init_buffers(void) -+{ -+ int i; -+ struct buffer_head *buffers; -+ size_t s = sizeof(struct buffer_head) * NUM_BUFFERS; -+ -+ /* -+ * FIXME: this should be a vmalloc. -+ */ -+ buffers = vmalloc(s); -+ if (!buffers) { -+ DMWARN("Couldn't allocate buffer heads."); -+ return -ENOMEM; -+ } -+ -+ memset(buffers, 0, s); -+ for (i = 0; i < NUM_BUFFERS; i++) { -+ if (i < NUM_BUFFERS - 1) -+ buffers[i].b_reqnext = &buffers[i + 1]; -+ init_waitqueue_head(&buffers[i].b_wait); -+ INIT_LIST_HEAD(&buffers[i].b_inode_buffers); -+ } -+ -+ _all_buffers = _free_buffers = buffers; -+ return 0; -+} -+ -+static void exit_buffers(void) -+{ -+ vfree(_all_buffers); -+} -+ -+static struct buffer_head *alloc_buffer(void) -+{ -+ int state = current->state; -+ struct buffer_head *r; -+ -+ set_current_state(TASK_UNINTERRUPTIBLE); -+ spin_lock(&_buffer_lock); -+ -+ if (!_free_buffers) -+ r = NULL; -+ else { -+ r = _free_buffers; -+ _free_buffers = _free_buffers->b_reqnext; -+ r->b_reqnext = NULL; -+ } -+ -+ spin_unlock(&_buffer_lock); -+ set_current_state(state); -+ -+ return r; -+} -+ -+/* -+ * Only called from interrupt context. -+ */ -+static void free_buffer(struct buffer_head *bh) -+{ -+ spin_lock(&_buffer_lock); -+ bh->b_reqnext = _free_buffers; -+ _free_buffers = bh; -+ spin_unlock(&_buffer_lock); -+} -+ -+/*----------------------------------------------------------------- -+ * kcopyd_jobs need to be allocated by the *clients* of kcopyd, -+ * for this reason we use a mempool to prevent the client from -+ * ever having to do io (which could cause a -+ * deadlock). -+ *---------------------------------------------------------------*/ -+#define MIN_JOBS NUM_PAGES -+ -+static kmem_cache_t *_job_cache = NULL; -+static mempool_t *_job_pool = NULL; -+ -+/* -+ * We maintain three lists of jobs: -+ * -+ * i) jobs waiting for pages -+ * ii) jobs that have pages, and are waiting for the io to be issued. -+ * iii) jobs that have completed. -+ * -+ * All three of these are protected by job_lock. -+ */ -+ -+static spinlock_t _job_lock = SPIN_LOCK_UNLOCKED; -+ -+static LIST_HEAD(_complete_jobs); -+static LIST_HEAD(_io_jobs); -+static LIST_HEAD(_pages_jobs); -+ -+static __init int init_jobs(void) -+{ -+ INIT_LIST_HEAD(&_complete_jobs); -+ INIT_LIST_HEAD(&_io_jobs); -+ INIT_LIST_HEAD(&_pages_jobs); -+ -+ _job_cache = kmem_cache_create("kcopyd-jobs", sizeof(struct kcopyd_job), -+ __alignof__(struct kcopyd_job), -+ 0, NULL, NULL); -+ if (!_job_cache) -+ return -ENOMEM; -+ -+ _job_pool = mempool_create(MIN_JOBS, -+ mempool_alloc_slab, -+ mempool_free_slab, _job_cache); -+ if (!_job_pool) { -+ kmem_cache_destroy(_job_cache); -+ return -ENOMEM; -+ } -+ -+ return 0; -+} -+ -+static void exit_jobs(void) -+{ -+ mempool_destroy(_job_pool); -+ kmem_cache_destroy(_job_cache); -+} -+ -+struct kcopyd_job *kcopyd_alloc_job(void) -+{ -+ struct kcopyd_job *job; -+ -+ job = mempool_alloc(_job_pool, GFP_KERNEL);; -+ if (!job) -+ return NULL; -+ -+ memset(job, 0, sizeof(*job)); -+ return job; -+} -+ -+void kcopyd_free_job(struct kcopyd_job *job) -+{ -+ mempool_free(job, _job_pool); -+} -+ -+/* -+ * Functions to push and pop a job onto the head of a given job -+ * list. -+ */ -+static inline struct kcopyd_job *__pop(struct list_head *jobs) -+{ -+ struct kcopyd_job *job = NULL; -+ -+ spin_lock(&_job_lock); -+ if (!list_empty(jobs)) { -+ job = list_entry(jobs->next, struct kcopyd_job, list); -+ list_del(&job->list); -+ } -+ spin_unlock(&_job_lock); -+ -+ return job; -+} -+ -+static struct kcopyd_job *pop(struct list_head *jobs) -+{ -+ int state = current->state; -+ struct kcopyd_job *job; -+ -+ set_current_state(TASK_UNINTERRUPTIBLE); -+ job = __pop(jobs); -+ set_current_state(state); -+ return job; -+} -+ -+static inline void __push(struct list_head *jobs, struct kcopyd_job *job) -+{ -+ spin_lock(&_job_lock); -+ list_add(&job->list, jobs); -+ spin_unlock(&_job_lock); -+} -+ -+static void push(struct list_head *jobs, struct kcopyd_job *job) -+{ -+ int state = current->state; -+ -+ set_current_state(TASK_UNINTERRUPTIBLE); -+ __push(jobs, job); -+ set_current_state(state); -+} -+ -+/* -+ * Completion function for one of our buffers. -+ */ -+static void end_bh(struct buffer_head *bh, int uptodate) -+{ -+ struct kcopyd_job *job = bh->b_private; -+ -+ mark_buffer_uptodate(bh, uptodate); -+ unlock_buffer(bh); -+ -+ if (!uptodate) -+ job->err = -EIO; -+ -+ /* are we the last ? */ -+ if (atomic_dec_and_test(&job->nr_incomplete)) { -+ __push(&_complete_jobs, job); -+ wake_kcopyd(); -+ } -+ -+ free_buffer(bh); -+} -+ -+static void dispatch_bh(struct kcopyd_job *job, -+ struct buffer_head *bh, int block) -+{ -+ int p; -+ -+ /* -+ * Add in the job offset -+ */ -+ block += job->offset >> job->block_shift; -+ bh->b_blocknr = (job->disk.sector >> job->block_shift) + block; -+ -+ p = block >> job->bpp_shift; -+ block &= job->bpp_mask; -+ -+ bh->b_dev = B_FREE; -+ bh->b_size = job->block_size; -+ set_bh_page(bh, job->pages[p], -+ (block << job->block_shift) << SECTOR_SHIFT); -+ bh->b_this_page = bh; -+ -+ init_buffer(bh, end_bh, job); -+ -+ bh->b_dev = job->disk.dev; -+ bh->b_state = ((1 << BH_Mapped) | (1 << BH_Lock) | (1 << BH_Req)); -+ -+ set_bit(BH_Uptodate, &bh->b_state); -+ if (job->rw == WRITE) -+ clear_bit(BH_Dirty, &bh->b_state); -+ -+ submit_bh(job->rw, bh); -+} -+ -+/* -+ * These three functions process 1 item from the corresponding -+ * job list. -+ * -+ * They return: -+ * < 0: error -+ * 0: success -+ * > 0: can't process yet. -+ */ -+static int run_complete_job(struct kcopyd_job *job) -+{ -+ job->callback(job); -+ return 0; -+} -+ -+/* -+ * Request io on as many buffer heads as we can currently get for -+ * a particular job. -+ */ -+static int run_io_job(struct kcopyd_job *job) -+{ -+ unsigned int block; -+ struct buffer_head *bh; -+ -+ for (block = atomic_read(&job->nr_requested); -+ block < job->nr_blocks; block++) { -+ bh = alloc_buffer(); -+ if (!bh) -+ break; -+ -+ atomic_inc(&job->nr_requested); -+ dispatch_bh(job, bh, block); -+ } -+ -+ return (block == job->nr_blocks) ? 0 : 1; -+} -+ -+static int run_pages_job(struct kcopyd_job *job) -+{ -+ int r; -+ -+ job->nr_pages = (job->disk.count + job->offset) / -+ (PAGE_SIZE / SECTOR_SIZE); -+ r = kcopyd_get_pages(job->nr_pages, job->pages); -+ if (!r) { -+ /* this job is ready for io */ -+ push(&_io_jobs, job); -+ return 0; -+ } -+ -+ if (r == -ENOMEM) -+ /* can complete now */ -+ return 1; -+ -+ return r; -+} -+ -+/* -+ * Run through a list for as long as possible. Returns the count -+ * of successful jobs. -+ */ -+static int process_jobs(struct list_head *jobs, int (*fn) (struct kcopyd_job *)) -+{ -+ struct kcopyd_job *job; -+ int r, count = 0; -+ -+ while ((job = pop(jobs))) { -+ -+ r = fn(job); -+ -+ if (r < 0) { -+ /* error this rogue job */ -+ job->err = r; -+ push(&_complete_jobs, job); -+ break; -+ } -+ -+ if (r > 0) { -+ /* -+ * We couldn't service this job ATM, so -+ * push this job back onto the list. -+ */ -+ push(jobs, job); -+ break; -+ } -+ -+ count++; -+ } -+ -+ return count; -+} -+ -+/* -+ * kcopyd does this every time it's woken up. -+ */ -+static void do_work(void) -+{ -+ int count; -+ -+ /* -+ * We loop round until there is no more work to do. -+ */ -+ do { -+ count = process_jobs(&_complete_jobs, run_complete_job); -+ count += process_jobs(&_io_jobs, run_io_job); -+ count += process_jobs(&_pages_jobs, run_pages_job); -+ -+ } while (count); -+ -+ run_task_queue(&tq_disk); -+} -+ -+/*----------------------------------------------------------------- -+ * The daemon -+ *---------------------------------------------------------------*/ -+static struct task_struct *_kcopyd_task; -+static atomic_t _kcopyd_must_die; -+static DECLARE_MUTEX(_run_lock); -+static DECLARE_WAIT_QUEUE_HEAD(_job_queue); -+ -+/* -+ * A day in the life of a little daemon. -+ */ -+static void kcopyd_cycle(void) -+{ -+ DECLARE_WAITQUEUE(wq, current); -+ -+ set_current_state(TASK_INTERRUPTIBLE); -+ add_wait_queue(&_job_queue, &wq); -+ -+ do_work(); -+ schedule(); -+ -+ set_current_state(TASK_RUNNING); -+ remove_wait_queue(&_job_queue, &wq); -+} -+ -+static int kcopyd(void *start_lock) -+{ -+ daemonize(); -+ strcpy(current->comm, "kcopyd"); -+ _kcopyd_task = current; -+ atomic_set(&_kcopyd_must_die, 0); -+ down(&_run_lock); -+ up((struct semaphore *) start_lock); -+ -+ while (!atomic_read(&_kcopyd_must_die)) -+ kcopyd_cycle(); -+ -+ up(&_run_lock); -+ DMINFO("kcopyd shutting down"); -+ return 0; -+} -+ -+static int start_daemon(void) -+{ -+ static pid_t pid = 0; -+ DECLARE_MUTEX(start_lock); -+ -+ down(&start_lock); -+ pid = kernel_thread(kcopyd, &start_lock, 0); -+ if (pid <= 0) { -+ DMERR("Failed to start kcopyd thread"); -+ return -EAGAIN; -+ } -+ -+ /* -+ * wait for the daemon to up this mutex. -+ */ -+ down(&start_lock); -+ DMINFO("Started kcopyd thread"); -+ -+ return 0; -+} -+ -+static int stop_daemon(void) -+{ -+ if (_kcopyd_task) { -+ atomic_set(&_kcopyd_must_die, 1); -+ wake_kcopyd(); -+ down(&_run_lock); -+ } -+ -+ return 0; -+} -+ -+static int wake_kcopyd(void) -+{ -+ int r = 0; -+ -+ /* Start the thread if we don't have one already */ -+ if (!_kcopyd_task) -+ r = start_daemon(); -+ -+ if (!r) -+ wake_up_interruptible(&_job_queue); -+ -+ return r; -+} -+ -+static int calc_shift(unsigned int n) -+{ -+ int s; -+ -+ for (s = 0; n; s++, n >>= 1) -+ ; -+ -+ return --s; -+} -+ -+static void calc_block_sizes(struct kcopyd_job *job) -+{ -+ job->block_size = get_hardsect_size(job->disk.dev); -+ job->block_shift = calc_shift(job->block_size / SECTOR_SIZE); -+ job->bpp_shift = PAGE_SHIFT - job->block_shift - SECTOR_SHIFT; -+ job->bpp_mask = (1 << job->bpp_shift) - 1; -+ job->nr_blocks = job->disk.count >> job->block_shift; -+ atomic_set(&job->nr_requested, 0); -+ atomic_set(&job->nr_incomplete, job->nr_blocks); -+} -+ -+int kcopyd_io(struct kcopyd_job *job) -+{ -+ calc_block_sizes(job); -+ push(job->pages[0] ? &_io_jobs : &_pages_jobs, job); -+ wake_kcopyd(); -+ return 0; -+} -+ -+/*----------------------------------------------------------------- -+ * The copier is implemented on top of the simpler async io -+ * daemon above. -+ *---------------------------------------------------------------*/ -+struct copy_info { -+ kcopyd_notify_fn notify; -+ void *notify_context; -+ -+ struct kcopyd_region to; -+}; -+ -+#define MIN_INFOS 128 -+static kmem_cache_t *_copy_cache = NULL; -+static mempool_t *_copy_pool = NULL; -+ -+static __init int init_copier(void) -+{ -+ _copy_cache = kmem_cache_create("kcopyd-info", -+ sizeof(struct copy_info), -+ __alignof__(struct copy_info), -+ 0, NULL, NULL); -+ if (!_copy_cache) -+ return -ENOMEM; -+ -+ _copy_pool = mempool_create(MIN_INFOS, -+ mempool_alloc_slab, -+ mempool_free_slab, _copy_cache); -+ if (!_copy_pool) { -+ kmem_cache_destroy(_copy_cache); -+ return -ENOMEM; -+ } -+ -+ return 0; -+} -+ -+static void exit_copier(void) -+{ -+ if (_copy_pool) -+ mempool_destroy(_copy_pool); -+ -+ if (_copy_cache) -+ kmem_cache_destroy(_copy_cache); -+} -+ -+static inline struct copy_info *alloc_copy_info(void) -+{ -+ return mempool_alloc(_copy_pool, GFP_KERNEL); -+} -+ -+static inline void free_copy_info(struct copy_info *info) -+{ -+ mempool_free(info, _copy_pool); -+} -+ -+void copy_complete(struct kcopyd_job *job) -+{ -+ struct copy_info *info = (struct copy_info *) job->context; -+ -+ if (info->notify) -+ info->notify(job->err, info->notify_context); -+ -+ free_copy_info(info); -+ kcopyd_free_pages(job->nr_pages, job->pages); -+ kcopyd_free_job(job); -+} -+ -+/* -+ * These callback functions implement the state machine that copies regions. -+ * FIXME: handle large regions. -+ */ -+void copy_write(struct kcopyd_job *job) -+{ -+ struct copy_info *info = (struct copy_info *) job->context; -+ -+ if (job->err && info->notify) { -+ info->notify(job->err, job->context); -+ kcopyd_free_job(job); -+ free_copy_info(info); -+ return; -+ } -+ -+ job->rw = WRITE; -+ memcpy(&job->disk, &info->to, sizeof(job->disk)); -+ job->callback = copy_complete; -+ job->context = info; -+ -+ /* -+ * Queue the write. -+ */ -+ kcopyd_io(job); -+} -+ -+int kcopyd_copy(struct kcopyd_region *from, -+ struct kcopyd_region *to, kcopyd_notify_fn fn, void *context) -+{ -+ struct copy_info *info; -+ struct kcopyd_job *job; -+ -+ /* -+ * Allocate a new copy_info. -+ */ -+ info = alloc_copy_info(); -+ if (!info) -+ return -ENOMEM; -+ -+ job = kcopyd_alloc_job(); -+ if (!job) { -+ free_copy_info(info); -+ return -ENOMEM; -+ } -+ -+ /* -+ * set up for the read. -+ */ -+ info->notify = fn; -+ info->notify_context = context; -+ memcpy(&info->to, to, sizeof(*to)); -+ -+ job->rw = READ; -+ memcpy(&job->disk, from, sizeof(*from)); -+ -+ job->offset = 0; -+ calc_block_sizes(job); -+ job->callback = copy_write; -+ job->context = info; -+ -+ /* -+ * Trigger job. -+ */ -+ kcopyd_io(job); -+ return 0; -+} -+ -+/*----------------------------------------------------------------- -+ * Unit setup -+ *---------------------------------------------------------------*/ -+static struct { -+ int (*init) (void); -+ void (*exit) (void); -+ -+} _inits[] = { -+#define xx(n) { init_ ## n, exit_ ## n} -+ xx(pages), -+ xx(buffers), -+ xx(jobs), -+ xx(copier) -+#undef xx -+}; -+ -+static int _has_initialised = 0; -+ -+int __init kcopyd_init(void) -+{ -+ const int count = sizeof(_inits) / sizeof(*_inits); -+ -+ int r, i; -+ -+ if (_has_initialised) -+ return 0; -+ -+ for (i = 0; i < count; i++) { -+ r = _inits[i].init(); -+ if (r) -+ goto bad; -+ } -+ -+ _has_initialised = 1; -+ return 0; -+ -+ bad: -+ while (i--) -+ _inits[i].exit(); -+ -+ return r; -+} -+ -+void kcopyd_exit(void) -+{ -+ int i = sizeof(_inits) / sizeof(*_inits); -+ -+ if (stop_daemon()) -+ DMWARN("Couldn't stop kcopyd."); -+ -+ while (i--) -+ _inits[i].exit(); -+ -+ _has_initialised = 0; -+} -diff -ruN linux-2.4.18/drivers/md/kcopyd.h linux/drivers/md/kcopyd.h ---- linux-2.4.18/drivers/md/kcopyd.h Thu Jan 1 01:00:00 1970 -+++ linux/drivers/md/kcopyd.h Tue Apr 23 22:23:30 2002 -@@ -0,0 +1,96 @@ -+/* -+ * Copyright (C) 2001 Sistina Software -+ * -+ * This file is released under the GPL. -+ */ -+ -+#ifndef DM_KCOPYD_H -+#define DM_KCOPYD_H -+ -+/* -+ * Needed for the definition of offset_t. -+ */ -+#include -+#include -+ -+struct kcopyd_region { -+ kdev_t dev; -+ offset_t sector; -+ offset_t count; -+}; -+ -+#define MAX_KCOPYD_PAGES 128 -+ -+struct kcopyd_job { -+ struct list_head list; -+ -+ /* -+ * Error state of the job. -+ */ -+ int err; -+ -+ /* -+ * Either READ or WRITE -+ */ -+ int rw; -+ -+ /* -+ * The source or destination for the transfer. -+ */ -+ struct kcopyd_region disk; -+ -+ int nr_pages; -+ struct page *pages[MAX_KCOPYD_PAGES]; -+ -+ /* -+ * Shifts and masks that will be useful when dispatching -+ * each buffer_head. -+ */ -+ offset_t offset; -+ offset_t block_size; -+ offset_t block_shift; -+ offset_t bpp_shift; /* blocks per page */ -+ offset_t bpp_mask; -+ -+ /* -+ * nr_blocks is how many buffer heads will have to be -+ * displatched to service this job, nr_requested is how -+ * many have been dispatched and nr_complete is how many -+ * have come back. -+ */ -+ unsigned int nr_blocks; -+ atomic_t nr_requested; -+ atomic_t nr_incomplete; -+ -+ /* -+ * Set this to ensure you are notified when the job has -+ * completed. 'context' is for callback to use. -+ */ -+ void (*callback) (struct kcopyd_job *job); -+ void *context; -+}; -+ -+/* -+ * Low level async io routines. -+ */ -+struct kcopyd_job *kcopyd_alloc_job(void); -+void kcopyd_free_job(struct kcopyd_job *job); -+ -+int kcopyd_queue_job(struct kcopyd_job *job); -+ -+/* -+ * Submit a copy job to kcopyd. This is built on top of the -+ * previous three fns. -+ */ -+typedef void (*kcopyd_notify_fn) (int err, void *context); -+ -+int kcopyd_copy(struct kcopyd_region *from, -+ struct kcopyd_region *to, kcopyd_notify_fn fn, void *context); -+ -+/* -+ * Setup/teardown. -+ */ -+int kcopyd_init(void); -+void kcopyd_exit(void); -+ -+#endif -diff -ruN linux-2.4.18/include/linux/device-mapper.h linux/include/linux/device-mapper.h ---- linux-2.4.18/include/linux/device-mapper.h Thu Jan 1 01:00:00 1970 -+++ linux/include/linux/device-mapper.h Thu Mar 7 16:56:22 2002 -@@ -0,0 +1,59 @@ -+/* -+ * Copyright (C) 2001 Sistina Software (UK) Limited. -+ * -+ * This file is released under the LGPL. -+ */ -+ -+#ifndef _LINUX_DEVICE_MAPPER_H -+#define _LINUX_DEVICE_MAPPER_H -+ -+#define DM_DIR "device-mapper" /* Slashes not supported */ -+#define DM_MAX_TYPE_NAME 16 -+#define DM_NAME_LEN 128 -+#define DM_UUID_LEN 129 -+ -+#ifdef __KERNEL__ -+ -+struct dm_table; -+struct dm_dev; -+typedef unsigned long offset_t; -+ -+ -+/* -+ * Prototypes for functions for a target -+ */ -+typedef int (*dm_ctr_fn)(struct dm_table *t, offset_t b, offset_t l, -+ int argc, char **argv, void **context); -+typedef void (*dm_dtr_fn)(struct dm_table *t, void *c); -+typedef int (*dm_map_fn)(struct buffer_head *bh, int rw, void *context); -+typedef int (*dm_err_fn)(struct buffer_head *bh, int rw, void *context); -+ -+ -+void dm_error(const char *message); -+ -+/* -+ * Constructors should call these functions to ensure destination devices -+ * are opened/closed correctly -+ */ -+int dm_table_get_device(struct dm_table *t, const char *path, -+ offset_t start, offset_t len, struct dm_dev **result); -+void dm_table_put_device(struct dm_table *table, struct dm_dev *d); -+ -+/* -+ * Information about a target type -+ */ -+struct target_type { -+ const char *name; -+ struct module *module; -+ dm_ctr_fn ctr; -+ dm_dtr_fn dtr; -+ dm_map_fn map; -+ dm_err_fn err; -+}; -+ -+int dm_register_target(struct target_type *t); -+int dm_unregister_target(struct target_type *t); -+ -+#endif /* __KERNEL__ */ -+ -+#endif /* _LINUX_DEVICE_MAPPER_H */ -diff -ruN linux-2.4.18/include/linux/dm-ioctl.h linux/include/linux/dm-ioctl.h ---- linux-2.4.18/include/linux/dm-ioctl.h Thu Jan 1 01:00:00 1970 -+++ linux/include/linux/dm-ioctl.h Tue Apr 23 22:38:54 2002 -@@ -0,0 +1,103 @@ -+/* -+ * Copyright (C) 2001 Sistina Software (UK) Limited. -+ * -+ * This file is released under the LGPL. -+ */ -+ -+#ifndef _LINUX_DM_IOCTL_H -+#define _LINUX_DM_IOCTL_H -+ -+#include "device-mapper.h" -+ -+/* -+ * Implements a traditional ioctl interface to the device mapper. -+ */ -+ -+/* -+ * All ioctl arguments consist of a single chunk of memory, with -+ * this structure at the start. -+ */ -+struct dm_ioctl { -+ char version[16]; -+ -+ unsigned long data_size; /* total size of data passed in -+ * including this struct */ -+ -+ unsigned long data_start; /* offset to start of data -+ * relative to start of this struct */ -+ -+ char name[DM_NAME_LEN]; /* device name */ -+ -+ unsigned int target_count; /* in/out */ -+ unsigned int open_count; /* out */ -+ unsigned int flags; /* in/out */ -+ -+ __kernel_dev_t dev; /* in/out */ -+ -+ char uuid[DM_UUID_LEN]; /* unique identifier for -+ * the block device */ -+}; -+ -+/* -+ * Used to specify tables. These structures appear after the -+ * dm_ioctl. -+ */ -+struct dm_target_spec { -+ int32_t status; /* used when reading from kernel only */ -+ unsigned long long sector_start; -+ unsigned long long length; -+ -+ char target_type[DM_MAX_TYPE_NAME]; -+ -+ unsigned long next; /* offset in bytes to next target_spec */ -+ -+ /* -+ * Parameter string starts immediately after this object. -+ * Be careful to add padding after string to ensure correct -+ * alignment of subsequent dm_target_spec. -+ */ -+}; -+ -+/* -+ * Used to retrieve the target dependencies. -+ */ -+struct dm_target_deps { -+ unsigned int count; -+ -+ __kernel_dev_t dev[0]; /* out */ -+}; -+ -+#define DM_IOCTL 0xfd -+ -+enum { -+ DM_CREATE_CMD = 0, -+ DM_REMOVE_CMD, -+ DM_SUSPEND_CMD, -+ DM_RELOAD_CMD, -+ DM_INFO_CMD, -+ DM_RENAME_CMD, -+ DM_VERSION_CMD, -+ DM_DEPS_CMD, -+ DM_REMOVE_ALL_CMD -+}; -+ -+#define DM_CREATE _IOWR(DM_IOCTL, DM_CREATE_CMD, struct dm_ioctl) -+#define DM_REMOVE _IOW(DM_IOCTL, DM_REMOVE_CMD, struct dm_ioctl) -+#define DM_SUSPEND _IOW(DM_IOCTL, DM_SUSPEND_CMD, struct dm_ioctl) -+#define DM_RELOAD _IOW(DM_IOCTL, DM_RELOAD_CMD, struct dm_ioctl) -+#define DM_INFO _IOWR(DM_IOCTL, DM_INFO_CMD, struct dm_ioctl) -+#define DM_RENAME _IOW(DM_IOCTL, DM_RENAME_CMD, struct dm_ioctl) -+#define DM_VERSION _IOR(DM_IOCTL, DM_VERSION_CMD, struct dm_ioctl) -+#define DM_DEPS _IOR(DM_IOCTL, DM_DEPS_CMD, struct dm_ioctl) -+#define DM_REMOVE_ALL _IOR(DM_IOCTL, DM_REMOVE_ALL_CMD, struct dm_ioctl) -+ -+#define DM_IOCTL_VERSION "0.94" -+#define DM_DRIVER_VERSION "0.94.10-ioctl (2002-04-23)" -+ -+/* Status bits */ -+#define DM_READONLY_FLAG 0x00000001 -+#define DM_SUSPEND_FLAG 0x00000002 -+#define DM_EXISTS_FLAG 0x00000004 -+#define DM_PERSISTENT_DEV_FLAG 0x00000008 -+ -+#endif /* _LINUX_DM_IOCTL_H */ -diff -ruN linux-2.4.18/include/linux/fs.h linux/include/linux/fs.h ---- linux-2.4.18/include/linux/fs.h Mon Mar 4 17:42:19 2002 -+++ linux/include/linux/fs.h Tue Apr 23 22:39:09 2002 -@@ -258,7 +258,10 @@ - char * b_data; /* pointer to data block */ - struct page *b_page; /* the page this bh is mapped to */ - void (*b_end_io)(struct buffer_head *bh, int uptodate); /* I/O completion */ -- void *b_private; /* reserved for b_end_io */ -+ void *b_private; /* reserved for b_end_io, also used by ext3 */ -+ void *b_bdev_private; /* a hack to get around ext3 using b_private -+ * after handing the buffer_head to the -+ * block layer */ - - unsigned long b_rsector; /* Real buffer location on disk */ - wait_queue_head_t b_wait; -diff -ruN linux-2.4.18/include/linux/mempool.h linux/include/linux/mempool.h ---- linux-2.4.18/include/linux/mempool.h Thu Jan 1 01:00:00 1970 -+++ linux/include/linux/mempool.h Tue Apr 23 22:39:09 2002 -@@ -0,0 +1,41 @@ -+/* -+ * memory buffer pool support -+ */ -+#ifndef _LINUX_MEMPOOL_H -+#define _LINUX_MEMPOOL_H -+ -+#include -+#include -+ -+struct mempool_s; -+typedef struct mempool_s mempool_t; -+ -+typedef void * (mempool_alloc_t)(int gfp_mask, void *pool_data); -+typedef void (mempool_free_t)(void *element, void *pool_data); -+ -+struct mempool_s { -+ spinlock_t lock; -+ int min_nr, curr_nr; -+ struct list_head elements; -+ -+ void *pool_data; -+ mempool_alloc_t *alloc; -+ mempool_free_t *free; -+ wait_queue_head_t wait; -+}; -+extern mempool_t * mempool_create(int min_nr, mempool_alloc_t *alloc_fn, -+ mempool_free_t *free_fn, void *pool_data); -+extern void mempool_resize(mempool_t *pool, int new_min_nr, int gfp_mask); -+extern void mempool_destroy(mempool_t *pool); -+extern void * mempool_alloc(mempool_t *pool, int gfp_mask); -+extern void mempool_free(void *element, mempool_t *pool); -+ -+ -+/* -+ * A mempool_alloc_t and mempool_free_t that get the memory from -+ * a slab that is passed in through pool_data. -+ */ -+void *mempool_alloc_slab(int gfp_mask, void *pool_data); -+void mempool_free_slab(void *element, void *pool_data); -+ -+#endif /* _LINUX_MEMPOOL_H */ -diff -ruN linux-2.4.18/mm/Makefile linux/mm/Makefile ---- linux-2.4.18/mm/Makefile Wed Oct 24 23:21:18 2001 -+++ linux/mm/Makefile Tue Apr 23 22:39:09 2002 -@@ -9,12 +9,12 @@ - - O_TARGET := mm.o - --export-objs := shmem.o filemap.o -+export-objs := shmem.o filemap.o memory.o page_alloc.o mempool.o - - obj-y := memory.o mmap.o filemap.o mprotect.o mlock.o mremap.o \ - vmalloc.o slab.o bootmem.o swap.o vmscan.o page_io.o \ - page_alloc.o swap_state.o swapfile.o numa.o oom_kill.o \ -- shmem.o -+ shmem.o mempool.o - - obj-$(CONFIG_HIGHMEM) += highmem.o - -diff -ruN linux-2.4.18/mm/mempool.c linux/mm/mempool.c ---- linux-2.4.18/mm/mempool.c Thu Jan 1 01:00:00 1970 -+++ linux/mm/mempool.c Tue Apr 23 22:39:09 2002 -@@ -0,0 +1,295 @@ -+/* -+ * linux/mm/mempool.c -+ * -+ * memory buffer pool support. Such pools are mostly used -+ * for guaranteed, deadlock-free memory allocations during -+ * extreme VM load. -+ * -+ * started by Ingo Molnar, Copyright (C) 2001 -+ */ -+ -+#include -+#include -+#include -+#include -+#include -+ -+/** -+ * mempool_create - create a memory pool -+ * @min_nr: the minimum number of elements guaranteed to be -+ * allocated for this pool. -+ * @alloc_fn: user-defined element-allocation function. -+ * @free_fn: user-defined element-freeing function. -+ * @pool_data: optional private data available to the user-defined functions. -+ * -+ * this function creates and allocates a guaranteed size, preallocated -+ * memory pool. The pool can be used from the mempool_alloc and mempool_free -+ * functions. This function might sleep. Both the alloc_fn() and the free_fn() -+ * functions might sleep - as long as the mempool_alloc function is not called -+ * from IRQ contexts. The element allocated by alloc_fn() must be able to -+ * hold a struct list_head. (8 bytes on x86.) -+ */ -+mempool_t * mempool_create(int min_nr, mempool_alloc_t *alloc_fn, -+ mempool_free_t *free_fn, void *pool_data) -+{ -+ mempool_t *pool; -+ int i; -+ -+ pool = kmalloc(sizeof(*pool), GFP_KERNEL); -+ if (!pool) -+ return NULL; -+ memset(pool, 0, sizeof(*pool)); -+ -+ spin_lock_init(&pool->lock); -+ pool->min_nr = min_nr; -+ pool->pool_data = pool_data; -+ INIT_LIST_HEAD(&pool->elements); -+ init_waitqueue_head(&pool->wait); -+ pool->alloc = alloc_fn; -+ pool->free = free_fn; -+ -+ /* -+ * First pre-allocate the guaranteed number of buffers. -+ */ -+ for (i = 0; i < min_nr; i++) { -+ void *element; -+ struct list_head *tmp; -+ element = pool->alloc(GFP_KERNEL, pool->pool_data); -+ -+ if (unlikely(!element)) { -+ /* -+ * Not enough memory - free the allocated ones -+ * and return: -+ */ -+ list_for_each(tmp, &pool->elements) { -+ element = tmp; -+ pool->free(element, pool->pool_data); -+ } -+ kfree(pool); -+ -+ return NULL; -+ } -+ tmp = element; -+ list_add(tmp, &pool->elements); -+ pool->curr_nr++; -+ } -+ return pool; -+} -+ -+/** -+ * mempool_resize - resize an existing memory pool -+ * @pool: pointer to the memory pool which was allocated via -+ * mempool_create(). -+ * @new_min_nr: the new minimum number of elements guaranteed to be -+ * allocated for this pool. -+ * @gfp_mask: the usual allocation bitmask. -+ * -+ * This function shrinks/grows the pool. In the case of growing, -+ * it cannot be guaranteed that the pool will be grown to the new -+ * size immediately, but new mempool_free() calls will refill it. -+ * -+ * Note, the caller must guarantee that no mempool_destroy is called -+ * while this function is running. mempool_alloc() & mempool_free() -+ * might be called (eg. from IRQ contexts) while this function executes. -+ */ -+void mempool_resize(mempool_t *pool, int new_min_nr, int gfp_mask) -+{ -+ int delta; -+ void *element; -+ unsigned long flags; -+ struct list_head *tmp; -+ -+ if (new_min_nr <= 0) -+ BUG(); -+ -+ spin_lock_irqsave(&pool->lock, flags); -+ if (new_min_nr < pool->min_nr) { -+ pool->min_nr = new_min_nr; -+ /* -+ * Free possible excess elements. -+ */ -+ while (pool->curr_nr > pool->min_nr) { -+ tmp = pool->elements.next; -+ if (tmp == &pool->elements) -+ BUG(); -+ list_del(tmp); -+ element = tmp; -+ pool->curr_nr--; -+ spin_unlock_irqrestore(&pool->lock, flags); -+ -+ pool->free(element, pool->pool_data); -+ -+ spin_lock_irqsave(&pool->lock, flags); -+ } -+ spin_unlock_irqrestore(&pool->lock, flags); -+ return; -+ } -+ delta = new_min_nr - pool->min_nr; -+ pool->min_nr = new_min_nr; -+ spin_unlock_irqrestore(&pool->lock, flags); -+ -+ /* -+ * We refill the pool up to the new treshold - but we dont -+ * (cannot) guarantee that the refill succeeds. -+ */ -+ while (delta) { -+ element = pool->alloc(gfp_mask, pool->pool_data); -+ if (!element) -+ break; -+ mempool_free(element, pool); -+ delta--; -+ } -+} -+ -+/** -+ * mempool_destroy - deallocate a memory pool -+ * @pool: pointer to the memory pool which was allocated via -+ * mempool_create(). -+ * -+ * this function only sleeps if the free_fn() function sleeps. The caller -+ * has to guarantee that no mempool_alloc() nor mempool_free() happens in -+ * this pool when calling this function. -+ */ -+void mempool_destroy(mempool_t *pool) -+{ -+ void *element; -+ struct list_head *head, *tmp; -+ -+ if (!pool) -+ return; -+ -+ head = &pool->elements; -+ for (tmp = head->next; tmp != head; ) { -+ element = tmp; -+ tmp = tmp->next; -+ pool->free(element, pool->pool_data); -+ pool->curr_nr--; -+ } -+ if (pool->curr_nr) -+ BUG(); -+ kfree(pool); -+} -+ -+/** -+ * mempool_alloc - allocate an element from a specific memory pool -+ * @pool: pointer to the memory pool which was allocated via -+ * mempool_create(). -+ * @gfp_mask: the usual allocation bitmask. -+ * -+ * this function only sleeps if the alloc_fn function sleeps or -+ * returns NULL. Note that due to preallocation, this function -+ * *never* fails when called from process contexts. (it might -+ * fail if called from an IRQ context.) -+ */ -+void * mempool_alloc(mempool_t *pool, int gfp_mask) -+{ -+ void *element; -+ unsigned long flags; -+ struct list_head *tmp; -+ int curr_nr; -+ DECLARE_WAITQUEUE(wait, current); -+ int gfp_nowait = gfp_mask & ~(__GFP_WAIT | __GFP_IO); -+ -+repeat_alloc: -+ element = pool->alloc(gfp_nowait, pool->pool_data); -+ if (likely(element != NULL)) -+ return element; -+ -+ /* -+ * If the pool is less than 50% full then try harder -+ * to allocate an element: -+ */ -+ if ((gfp_mask != gfp_nowait) && (pool->curr_nr <= pool->min_nr/2)) { -+ element = pool->alloc(gfp_mask, pool->pool_data); -+ if (likely(element != NULL)) -+ return element; -+ } -+ -+ /* -+ * Kick the VM at this point. -+ */ -+ wakeup_bdflush(); -+ -+ spin_lock_irqsave(&pool->lock, flags); -+ if (likely(pool->curr_nr)) { -+ tmp = pool->elements.next; -+ list_del(tmp); -+ element = tmp; -+ pool->curr_nr--; -+ spin_unlock_irqrestore(&pool->lock, flags); -+ return element; -+ } -+ spin_unlock_irqrestore(&pool->lock, flags); -+ -+ /* We must not sleep in the GFP_ATOMIC case */ -+ if (gfp_mask == gfp_nowait) -+ return NULL; -+ -+ run_task_queue(&tq_disk); -+ -+ add_wait_queue_exclusive(&pool->wait, &wait); -+ set_task_state(current, TASK_UNINTERRUPTIBLE); -+ -+ spin_lock_irqsave(&pool->lock, flags); -+ curr_nr = pool->curr_nr; -+ spin_unlock_irqrestore(&pool->lock, flags); -+ -+ if (!curr_nr) -+ schedule(); -+ -+ current->state = TASK_RUNNING; -+ remove_wait_queue(&pool->wait, &wait); -+ -+ goto repeat_alloc; -+} -+ -+/** -+ * mempool_free - return an element to the pool. -+ * @element: pool element pointer. -+ * @pool: pointer to the memory pool which was allocated via -+ * mempool_create(). -+ * -+ * this function only sleeps if the free_fn() function sleeps. -+ */ -+void mempool_free(void *element, mempool_t *pool) -+{ -+ unsigned long flags; -+ -+ if (pool->curr_nr < pool->min_nr) { -+ spin_lock_irqsave(&pool->lock, flags); -+ if (pool->curr_nr < pool->min_nr) { -+ list_add(element, &pool->elements); -+ pool->curr_nr++; -+ spin_unlock_irqrestore(&pool->lock, flags); -+ wake_up(&pool->wait); -+ return; -+ } -+ spin_unlock_irqrestore(&pool->lock, flags); -+ } -+ pool->free(element, pool->pool_data); -+} -+ -+/* -+ * A commonly used alloc and free fn. -+ */ -+void *mempool_alloc_slab(int gfp_mask, void *pool_data) -+{ -+ kmem_cache_t *mem = (kmem_cache_t *) pool_data; -+ return kmem_cache_alloc(mem, gfp_mask); -+} -+ -+void mempool_free_slab(void *element, void *pool_data) -+{ -+ kmem_cache_t *mem = (kmem_cache_t *) pool_data; -+ kmem_cache_free(mem, element); -+} -+ -+ -+EXPORT_SYMBOL(mempool_create); -+EXPORT_SYMBOL(mempool_resize); -+EXPORT_SYMBOL(mempool_destroy); -+EXPORT_SYMBOL(mempool_alloc); -+EXPORT_SYMBOL(mempool_free); -+EXPORT_SYMBOL(mempool_alloc_slab); -+EXPORT_SYMBOL(mempool_free_slab); -+ -- 2.43.5