Merge tag 'for-5.2-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fix from David Sterba:
 "One regression fix to TRIM ioctl.

  The range cannot be used as its meaning can be confusing regarding
  physical and logical addresses. This confusion in code led to
  potential corruptions when the range overlapped data.

  The original patch made it to several stable kernels and was promptly
  reverted, the version for master branch is different due to additional
  changes but the change is effectively the same"

* tag 'for-5.2-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: Always trim all unallocated space in btrfs_trim_free_extents

1 files changed, 3 insertions, 25 deletions

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 1aee51a9f3bf..c7adff343ba9 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -11137,13 +11137,11 @@ int btrfs_error_unpin_extent_range(struct btrfs_fs_info *fs_info,
  * it while performing the free space search since we have already
  * held back allocations.
  */
-static int btrfs_trim_free_extents(struct btrfs_device *device,
-				   struct fstrim_range *range, u64 *trimmed)
+static int btrfs_trim_free_extents(struct btrfs_device *device, u64 *trimmed)
 {
-	u64 start, len = 0, end = 0;
+	u64 start = SZ_1M, len = 0, end = 0;
 	int ret;
 
-	start = max_t(u64, range->start, SZ_1M);
 	*trimmed = 0;
 
 	/* Discard not supported = nothing to do. */
@@ -11186,22 +11184,6 @@ static int btrfs_trim_free_extents(struct btrfs_device *device,
 			break;
 		}
 
-		/* Keep going until we satisfy minlen or reach end of space */
-		if (len < range->minlen) {
-			mutex_unlock(&fs_info->chunk_mutex);
-			start += len;
-			continue;
-		}
-
-		/* If we are out of the passed range break */
-		if (start > range->start + range->len - 1) {
-			mutex_unlock(&fs_info->chunk_mutex);
-			break;
-		}
-
-		start = max(range->start, start);
-		len = min(range->len, len);
-
 		ret = btrfs_issue_discard(device->bdev, start, len,
 					  &bytes);
 		if (!ret)
@@ -11216,10 +11198,6 @@ static int btrfs_trim_free_extents(struct btrfs_device *device,
 		start += len;
 		*trimmed += bytes;
 
-		/* We've trimmed enough */
-		if (*trimmed >= range->len)
-			break;
-
 		if (fatal_signal_pending(current)) {
 			ret = -ERESTARTSYS;
 			break;
@@ -11303,7 +11281,7 @@ int btrfs_trim_fs(struct btrfs_fs_info *fs_info, struct fstrim_range *range)
 	mutex_lock(&fs_info->fs_devices->device_list_mutex);
 	devices = &fs_info->fs_devices->devices;
 	list_for_each_entry(device, devices, dev_list) {
-		ret = btrfs_trim_free_extents(device, range, &group_trimmed);
+		ret = btrfs_trim_free_extents(device, &group_trimmed);
 		if (ret) {
 			dev_failed++;
 			dev_ret = ret;