diff options
Diffstat (limited to 'drivers/md/md-bitmap.c')
| -rw-r--r-- | drivers/md/md-bitmap.c | 28 |
1 files changed, 26 insertions, 2 deletions
diff --git a/drivers/md/md-bitmap.c b/drivers/md/md-bitmap.c index adada558a1b0..49c46f3aea57 100644 --- a/drivers/md/md-bitmap.c +++ b/drivers/md/md-bitmap.c @@ -2476,11 +2476,35 @@ backlog_store(struct mddev *mddev, const char *buf, size_t len) { unsigned long backlog; unsigned long old_mwb = mddev->bitmap_info.max_write_behind; + struct md_rdev *rdev; + bool has_write_mostly = false; int rv = kstrtoul(buf, 10, &backlog); if (rv) return rv; if (backlog > COUNTER_MAX) return -EINVAL; + + rv = mddev_lock(mddev); + if (rv) + return rv; + + /* + * Without write mostly device, it doesn't make sense to set + * backlog for max_write_behind. + */ + rdev_for_each(rdev, mddev) { + if (test_bit(WriteMostly, &rdev->flags)) { + has_write_mostly = true; + break; + } + } + if (!has_write_mostly) { + pr_warn_ratelimited("%s: can't set backlog, no write mostly device available\n", + mdname(mddev)); + mddev_unlock(mddev); + return -EINVAL; + } + mddev->bitmap_info.max_write_behind = backlog; if (!backlog && mddev->serial_info_pool) { /* serial_info_pool is not needed if backlog is zero */ @@ -2488,13 +2512,13 @@ backlog_store(struct mddev *mddev, const char *buf, size_t len) mddev_destroy_serial_pool(mddev, NULL, false); } else if (backlog && !mddev->serial_info_pool) { /* serial_info_pool is needed since backlog is not zero */ - struct md_rdev *rdev; - rdev_for_each(rdev, mddev) mddev_create_serial_pool(mddev, rdev, false); } if (old_mwb != backlog) md_bitmap_update_sb(mddev->bitmap); + + mddev_unlock(mddev); return len; } |