diff options
author | Shaohua Li <shli@fb.com> | 2016-07-30 20:05:31 +0300 |
---|---|---|
committer | Shaohua Li <shli@fb.com> | 2016-08-06 08:02:40 +0300 |
commit | d9dd26b20cff88b45d861ec786d86b1c9bd2ee60 (patch) | |
tree | 6aa93f54bf5329ad88c0406041b3185511c29680 | |
parent | ff00d3b4e5e4395c825e8ec628f25932d812f31a (diff) | |
download | linux-d9dd26b20cff88b45d861ec786d86b1c9bd2ee60.tar.xz |
MD: hold mddev lock to change bitmap location
Changing the location changes a lot of things. Holding the lock to avoid race.
This makes the .quiesce called with mddev lock hold too.
Acked-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
-rw-r--r-- | drivers/md/bitmap.c | 47 |
1 files changed, 33 insertions, 14 deletions
diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c index 6fff794e0c72..13041ee37ad6 100644 --- a/drivers/md/bitmap.c +++ b/drivers/md/bitmap.c @@ -2183,19 +2183,29 @@ location_show(struct mddev *mddev, char *page) static ssize_t location_store(struct mddev *mddev, const char *buf, size_t len) { + int rv; + rv = mddev_lock(mddev); + if (rv) + return rv; if (mddev->pers) { - if (!mddev->pers->quiesce) - return -EBUSY; - if (mddev->recovery || mddev->sync_thread) - return -EBUSY; + if (!mddev->pers->quiesce) { + rv = -EBUSY; + goto out; + } + if (mddev->recovery || mddev->sync_thread) { + rv = -EBUSY; + goto out; + } } if (mddev->bitmap || mddev->bitmap_info.file || mddev->bitmap_info.offset) { /* bitmap already configured. Only option is to clear it */ - if (strncmp(buf, "none", 4) != 0) - return -EBUSY; + if (strncmp(buf, "none", 4) != 0) { + rv = -EBUSY; + goto out; + } if (mddev->pers) { mddev->pers->quiesce(mddev, 1); bitmap_destroy(mddev); @@ -2214,21 +2224,25 @@ location_store(struct mddev *mddev, const char *buf, size_t len) /* nothing to be done */; else if (strncmp(buf, "file:", 5) == 0) { /* Not supported yet */ - return -EINVAL; + rv = -EINVAL; + goto out; } else { - int rv; if (buf[0] == '+') rv = kstrtoll(buf+1, 10, &offset); else rv = kstrtoll(buf, 10, &offset); if (rv) - return rv; - if (offset == 0) - return -EINVAL; + goto out; + if (offset == 0) { + rv = -EINVAL; + goto out; + } if (mddev->bitmap_info.external == 0 && mddev->major_version == 0 && - offset != mddev->bitmap_info.default_offset) - return -EINVAL; + offset != mddev->bitmap_info.default_offset) { + rv = -EINVAL; + goto out; + } mddev->bitmap_info.offset = offset; if (mddev->pers) { struct bitmap *bitmap; @@ -2245,7 +2259,7 @@ location_store(struct mddev *mddev, const char *buf, size_t len) mddev->pers->quiesce(mddev, 0); if (rv) { bitmap_destroy(mddev); - return rv; + goto out; } } } @@ -2257,6 +2271,11 @@ location_store(struct mddev *mddev, const char *buf, size_t len) set_bit(MD_CHANGE_DEVS, &mddev->flags); md_wakeup_thread(mddev->thread); } + rv = 0; +out: + mddev_unlock(mddev); + if (rv) + return rv; return len; } |