It's currently u64 which gets instantly translated either to LONG_MAX
(if U64_MAX is passed) or casted to an unsigned long (which is in fact,
wrong because iwriteback_control::nr_to_write is a signed, long type).
Just convert the function's argument to be long time which obviates the
need to manually convert u64 value to a long. Adjust all call sites
which pass U64_MAX to pass LONG_MAX. Finally ensure that in
shrink_delalloc the u64 is converted to a long without overflowing,
resulting in a negative number.
Signed-off-by: Nikolay Borisov <nbori...@suse.com>
---
David,
Here are 2 patches which I believe should be folded into
"btrfs: shrink delalloc pages instead of full inodes" so as to avoid needless
casts and a possible overflow, resulting in negative nr_to_write value.
fs/btrfs/ctree.h | 2 +-
fs/btrfs/dev-replace.c | 2 +-
fs/btrfs/inode.c | 6 +++---
fs/btrfs/ioctl.c | 2 +-
fs/btrfs/space-info.c | 3 ++-
5 files changed, 8 insertions(+), 7 deletions(-)
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 05f009fbbd55..3dc67f241919 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -3101,7 +3101,7 @@ int btrfs_truncate_inode_items(struct btrfs_trans_handle
*trans,
u32 min_type);
int btrfs_start_delalloc_snapshot(struct btrfs_root *root);
-int btrfs_start_delalloc_roots(struct btrfs_fs_info *fs_info, u64 nr,
+int btrfs_start_delalloc_roots(struct btrfs_fs_info *fs_info, long nr,
bool in_reclaim_context);
int btrfs_set_extent_delalloc(struct btrfs_inode *inode, u64 start, u64 end,
unsigned int extra_bits,
diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index 324f646d6e5e..bc73f798ce3a 100644
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -715,7 +715,7 @@ static int btrfs_dev_replace_finishing(struct btrfs_fs_info
*fs_info,
* flush all outstanding I/O and inode extent mappings before the
* copy operation is declared as being finished
*/
- ret = btrfs_start_delalloc_roots(fs_info, U64_MAX, false);
+ ret = btrfs_start_delalloc_roots(fs_info, LONG_MAX, false);
if (ret) {
mutex_unlock(&dev_replace->lock_finishing_cancel_unmount);
return ret;
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 5c173a30a97a..69e24341afc0 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -9474,11 +9474,11 @@ int btrfs_start_delalloc_snapshot(struct btrfs_root
*root)
return start_delalloc_inodes(root, &wbc, true, false);
}
-int btrfs_start_delalloc_roots(struct btrfs_fs_info *fs_info, u64 nr,
+int btrfs_start_delalloc_roots(struct btrfs_fs_info *fs_info, long nr,
bool in_reclaim_context)
{
struct writeback_control wbc = {
- .nr_to_write = (nr == U64_MAX) ? LONG_MAX : (unsigned long)nr,
+ .nr_to_write = nr,
.sync_mode = WB_SYNC_NONE,
.range_start = 0,
.range_end = LLONG_MAX,
@@ -9500,7 +9500,7 @@ int btrfs_start_delalloc_roots(struct btrfs_fs_info
*fs_info, u64 nr,
* Reset nr_to_write here so we know that we're doing a full
* flush.
*/
- if (nr == U64_MAX)
+ if (nr == LONG_MAX)
wbc.nr_to_write = LONG_MAX;
root = list_first_entry(&splice, struct btrfs_root,
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index db29c1b54daa..998ea561d934 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -4973,7 +4973,7 @@ long btrfs_ioctl(struct file *file, unsigned int
case BTRFS_IOC_SYNC: {
int ret;
- ret = btrfs_start_delalloc_roots(fs_info, U64_MAX, false);
+ ret = btrfs_start_delalloc_roots(fs_info, LONG_MAX, false);
if (ret)
return ret;
ret = btrfs_sync_fs(inode->i_sb, 1);
diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c
index e8347461c8dd..84fb94e78a8f 100644
--- a/fs/btrfs/space-info.c
+++ b/fs/btrfs/space-info.c
@@ -532,7 +532,8 @@ static void shrink_delalloc(struct btrfs_fs_info *fs_info,
loops = 0;
while ((delalloc_bytes || dio_bytes) && loops < 3) {
- u64 nr_pages = min(delalloc_bytes, to_reclaim) >> PAGE_SHIFT;
+ u64 temp = min(delalloc_bytes, to_reclaim) >> PAGE_SHIFT;
+ long nr_pages = min_t(u64, temp, LONG_MAX);
btrfs_start_delalloc_roots(fs_info, nr_pages, true);
--
2.25.1
