From 6b1629455ac1806d4b7064a3f872e05f6c2f3c5a Mon Sep 17 00:00:00 2001 From: Peter Rajnoha Date: Thu, 22 Sep 2011 17:09:48 +0000 Subject: [PATCH] Add dm_task_retry_remove fn to use retry logic for device removal. This call ensures that the dm device removal is retried several times before failing. --- WHATS_NEW_DM | 2 +- libdm/ioctl/libdm-iface.c | 50 ++++++++++++++++++++++--------------- libdm/ioctl/libdm-targets.h | 1 + libdm/libdevmapper.h | 1 + 4 files changed, 33 insertions(+), 21 deletions(-) diff --git a/WHATS_NEW_DM b/WHATS_NEW_DM index eec750e07..0ed1a14a0 100644 --- a/WHATS_NEW_DM +++ b/WHATS_NEW_DM @@ -1,6 +1,6 @@ Version 1.02.68 - ================================== - Retry DM_DEVICE_REMOVE ioctl if device is busy. + Add dm_task_retry_remove fn to use retry logic for device removal. Remove unused passed parameters for _mirror_emit_segment_line(). Add dm_config and string character escaping functions to libdevmapper. Mark unreleased memory pools as internal error. diff --git a/libdm/ioctl/libdm-iface.c b/libdm/ioctl/libdm-iface.c index a6097d35d..3bd5a7c1e 100644 --- a/libdm/ioctl/libdm-iface.c +++ b/libdm/ioctl/libdm-iface.c @@ -828,6 +828,13 @@ int dm_task_secure_data(struct dm_task *dmt) return 1; } +int dm_task_retry_remove(struct dm_task *dmt) +{ + dmt->retry_remove = 1; + + return 1; +} + int dm_task_query_inactive_table(struct dm_task *dmt) { dmt->query_inactive_table = 1; @@ -1539,16 +1546,15 @@ static const char *_sanitise_message(char *message) return sanitised_message; } -#define DM_REMOVE_IOCTL_RETRIES 25 - static struct dm_ioctl *_do_dm_ioctl(struct dm_task *dmt, unsigned command, - unsigned repeat_count) + unsigned buffer_repeat_count, + unsigned retry_repeat_count, + int *retryable) { struct dm_ioctl *dmi; int ioctl_with_uevent; - int retries = DM_REMOVE_IOCTL_RETRIES; - dmi = _flatten(dmt, repeat_count); + dmi = _flatten(dmt, buffer_repeat_count); if (!dmi) { log_error("Couldn't create ioctl argument."); return NULL; @@ -1609,7 +1615,7 @@ static struct dm_ioctl *_do_dm_ioctl(struct dm_task *dmt, unsigned command, } log_debug("dm %s %s%s %s%s%s %s%.0d%s%.0d%s" - "%s%c%c%s%s%s%s%s %.0" PRIu64 " %s [%u]", + "%s%c%c%s%s%s%s%s%s %.0" PRIu64 " %s [%u] (*%u)", _cmd_data_v4[dmt->type].name, dmt->new_uuid ? "UUID " : "", dmi->name, dmi->uuid, dmt->newname ? " " : "", @@ -1624,29 +1630,18 @@ static struct dm_ioctl *_do_dm_ioctl(struct dm_task *dmt, unsigned command, dmt->no_flush ? 'N' : 'F', dmt->read_only ? "R" : "", dmt->skip_lockfs ? "S " : "", + dmt->retry_remove ? "T " : "", dmt->secure_data ? "W " : "", dmt->query_inactive_table ? "I " : "", dmt->enable_checks ? "C" : "", dmt->sector, _sanitise_message(dmt->message), - dmi->data_size); + dmi->data_size, retry_repeat_count); #ifdef DM_IOCTLS -repeat_dm_ioctl: if (ioctl(_control_fd, command, dmi) < 0) { if (errno == ENXIO && ((dmt->type == DM_DEVICE_INFO) || (dmt->type == DM_DEVICE_MKNODES) || (dmt->type == DM_DEVICE_STATUS))) dmi->flags &= ~DM_EXISTS_FLAG; /* FIXME */ - /* - * FIXME: This is a workaround for asynchronous events generated - * as a result of using the WATCH udev rule with which we - * have no way of synchronizing. Processing such events in - * parallel causes devices to be open. - */ - else if (errno == EBUSY && (dmt->type == DM_DEVICE_REMOVE) && retries--) { - log_debug("device-mapper: device is busy, retrying removal"); - usleep(200000); - goto repeat_dm_ioctl; - } else { if (_log_suppress) log_verbose("device-mapper: %s ioctl " @@ -1658,6 +1653,9 @@ repeat_dm_ioctl: "failed: %s", _cmd_data_v4[dmt->type].name, strerror(errno)); + + *retryable = errno == EBUSY; + _dm_zfree_dmi(dmi); return NULL; } @@ -1680,6 +1678,9 @@ void dm_task_update_nodes(void) update_devs(); } +#define DM_IOCTL_RETRIES 25 +#define DM_RETRY_USLEEP_DELAY 200000 + int dm_task_run(struct dm_task *dmt) { struct dm_ioctl *dmi; @@ -1687,6 +1688,8 @@ int dm_task_run(struct dm_task *dmt) int check_udev; int rely_on_udev; int suspended_counter; + unsigned ioctl_retry = 1; + int retryable; if ((unsigned) dmt->type >= (sizeof(_cmd_data_v4) / sizeof(*_cmd_data_v4))) { @@ -1734,7 +1737,14 @@ int dm_task_run(struct dm_task *dmt) /* FIXME Detect and warn if cookie set but should not be. */ repeat_ioctl: - if (!(dmi = _do_dm_ioctl(dmt, command, _ioctl_buffer_double_factor))) { + if (!(dmi = _do_dm_ioctl(dmt, command, _ioctl_buffer_double_factor, + ioctl_retry, &retryable))) { + if (retryable && dmt->type == DM_DEVICE_REMOVE && + dmt->retry_remove && ++ioctl_retry <= DM_IOCTL_RETRIES) { + usleep(DM_RETRY_USLEEP_DELAY); + goto repeat_ioctl; + } + _udev_complete(dmt); return 0; } diff --git a/libdm/ioctl/libdm-targets.h b/libdm/ioctl/libdm-targets.h index 82792e00d..ca08fe835 100644 --- a/libdm/ioctl/libdm-targets.h +++ b/libdm/ioctl/libdm-targets.h @@ -63,6 +63,7 @@ struct dm_task { int cookie_set; int new_uuid; int secure_data; + int retry_remove; int enable_checks; char *uuid; diff --git a/libdm/libdevmapper.h b/libdm/libdevmapper.h index c0b9fff19..628d7dac2 100644 --- a/libdm/libdevmapper.h +++ b/libdm/libdevmapper.h @@ -191,6 +191,7 @@ int dm_task_skip_lockfs(struct dm_task *dmt); int dm_task_query_inactive_table(struct dm_task *dmt); int dm_task_suppress_identical_reload(struct dm_task *dmt); int dm_task_secure_data(struct dm_task *dmt); +int dm_task_retry_remove(struct dm_task *dmt); /* * Enable checks for common mistakes such as issuing ioctls in an unsafe order. -- 2.43.5