diff options
| -rw-r--r-- | drivers/md/dm-ioctl.c | 1 | ||||
| -rw-r--r-- | drivers/md/dm-mpath.c | 100 | ||||
| -rw-r--r-- | include/uapi/linux/dm-ioctl.h | 9 |
3 files changed, 107 insertions, 3 deletions
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c index d42eac944eb5..4165fef4c170 100644 --- a/drivers/md/dm-ioctl.c +++ b/drivers/md/dm-ioctl.c @@ -1885,6 +1885,7 @@ static ioctl_fn lookup_ioctl(unsigned int cmd, int *ioctl_flags) {DM_DEV_SET_GEOMETRY_CMD, 0, dev_set_geometry}, {DM_DEV_ARM_POLL_CMD, IOCTL_FLAGS_NO_PARAMS, dev_arm_poll}, {DM_GET_TARGET_VERSION_CMD, 0, get_target_version}, + {DM_MPATH_PROBE_PATHS_CMD, 0, NULL}, /* block device ioctl */ }; if (unlikely(cmd >= ARRAY_SIZE(_ioctls))) diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c index 909ed6890ba5..53861ad5dd1d 100644 --- a/drivers/md/dm-mpath.c +++ b/drivers/md/dm-mpath.c @@ -2021,6 +2021,94 @@ out: return r; } +/* + * Perform a minimal read from the given path to find out whether the + * path still works. If a path error occurs, fail it. + */ +static int probe_path(struct pgpath *pgpath) +{ + struct block_device *bdev = pgpath->path.dev->bdev; + unsigned int read_size = bdev_logical_block_size(bdev); + struct page *page; + struct bio *bio; + blk_status_t status; + int r = 0; + + if (WARN_ON_ONCE(read_size > PAGE_SIZE)) + return -EINVAL; + + page = alloc_page(GFP_KERNEL); + if (!page) + return -ENOMEM; + + /* Perform a minimal read: Sector 0, length read_size */ + bio = bio_alloc(bdev, 1, REQ_OP_READ, GFP_KERNEL); + if (!bio) { + r = -ENOMEM; + goto out; + } + + bio->bi_iter.bi_sector = 0; + __bio_add_page(bio, page, read_size, 0); + submit_bio_wait(bio); + status = bio->bi_status; + bio_put(bio); + + if (status && blk_path_error(status)) + fail_path(pgpath); + +out: + __free_page(page); + return r; +} + +/* + * Probe all active paths in current_pg to find out whether they still work. + * Fail all paths that do not work. + * + * Return -ENOTCONN if no valid path is left (even outside of current_pg). We + * cannot probe paths in other pgs without switching current_pg, so if valid + * paths are only in different pgs, they may or may not work. Additionally + * we should not probe paths in a pathgroup that is in the process of + * Initializing. Userspace can submit a request and we'll switch and wait + * for the pathgroup to be initialized. If the request fails, it may need to + * probe again. + */ +static int probe_active_paths(struct multipath *m) +{ + struct pgpath *pgpath; + struct priority_group *pg; + unsigned long flags; + int r = 0; + + mutex_lock(&m->work_mutex); + + spin_lock_irqsave(&m->lock, flags); + if (test_bit(MPATHF_QUEUE_IO, &m->flags)) + pg = NULL; + else + pg = m->current_pg; + spin_unlock_irqrestore(&m->lock, flags); + + if (pg) { + list_for_each_entry(pgpath, &pg->pgpaths, list) { + if (!pgpath->is_active) + continue; + + r = probe_path(pgpath); + if (r < 0) + goto out; + } + } + + if (!atomic_read(&m->nr_valid_paths)) + r = -ENOTCONN; + +out: + mutex_unlock(&m->work_mutex); + return r; +} + static int multipath_prepare_ioctl(struct dm_target *ti, struct block_device **bdev, unsigned int cmd, unsigned long arg, @@ -2031,6 +2119,16 @@ static int multipath_prepare_ioctl(struct dm_target *ti, unsigned long flags; int r; + if (_IOC_TYPE(cmd) == DM_IOCTL) { + *forward = false; + switch (cmd) { + case DM_MPATH_PROBE_PATHS: + return probe_active_paths(m); + default: + return -ENOTTY; + } + } + pgpath = READ_ONCE(m->current_pgpath); if (!pgpath || !mpath_double_check_test_bit(MPATHF_QUEUE_IO, m)) pgpath = choose_pgpath(m, 0); @@ -2182,7 +2280,7 @@ static int multipath_busy(struct dm_target *ti) */ static struct target_type multipath_target = { .name = "multipath", - .version = {1, 14, 0}, + .version = {1, 15, 0}, .features = DM_TARGET_SINGLETON | DM_TARGET_IMMUTABLE | DM_TARGET_PASSES_INTEGRITY, .module = THIS_MODULE, diff --git a/include/uapi/linux/dm-ioctl.h b/include/uapi/linux/dm-ioctl.h index b08c7378164d..3225e025e30e 100644 --- a/include/uapi/linux/dm-ioctl.h +++ b/include/uapi/linux/dm-ioctl.h @@ -258,10 +258,12 @@ enum { DM_DEV_SET_GEOMETRY_CMD, DM_DEV_ARM_POLL_CMD, DM_GET_TARGET_VERSION_CMD, + DM_MPATH_PROBE_PATHS_CMD, }; #define DM_IOCTL 0xfd +/* Control device ioctls */ #define DM_VERSION _IOWR(DM_IOCTL, DM_VERSION_CMD, struct dm_ioctl) #define DM_REMOVE_ALL _IOWR(DM_IOCTL, DM_REMOVE_ALL_CMD, struct dm_ioctl) #define DM_LIST_DEVICES _IOWR(DM_IOCTL, DM_LIST_DEVICES_CMD, struct dm_ioctl) @@ -285,10 +287,13 @@ enum { #define DM_TARGET_MSG _IOWR(DM_IOCTL, DM_TARGET_MSG_CMD, struct dm_ioctl) #define DM_DEV_SET_GEOMETRY _IOWR(DM_IOCTL, DM_DEV_SET_GEOMETRY_CMD, struct dm_ioctl) +/* Block device ioctls */ +#define DM_MPATH_PROBE_PATHS _IO(DM_IOCTL, DM_MPATH_PROBE_PATHS_CMD) + #define DM_VERSION_MAJOR 4 -#define DM_VERSION_MINOR 49 +#define DM_VERSION_MINOR 50 #define DM_VERSION_PATCHLEVEL 0 -#define DM_VERSION_EXTRA "-ioctl (2025-01-17)" +#define DM_VERSION_EXTRA "-ioctl (2025-04-28)" /* Status bits */ #define DM_READONLY_FLAG (1 << 0) /* In/Out */ |