On 4/27/20 11:49 PM, Christoph Hellwig wrote:
By moving FIEMAP_FLAG_SYNC handling to fiemap_prep we ensure it is
handled once instead of duplicated, but can still be done under fs locks,
like xfs/iomap intended with its duplicate handling. Also make sure the
error value of filemap_write_and_wait is propagated to user space.
Forgot to remove filemap_write_and_wait() from
ext4_ioctl_get_es_cache() ?
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
fs/btrfs/inode.c | 4 +---
fs/cifs/smb2ops.c | 3 +--
fs/ext4/extents.c | 2 +-
fs/f2fs/data.c | 3 +--
fs/ioctl.c | 10 ++++++----
fs/iomap/fiemap.c | 8 +-------
fs/nilfs2/inode.c | 2 +-
fs/ocfs2/extent_map.c | 5 +----
fs/overlayfs/inode.c | 4 ----
9 files changed, 13 insertions(+), 28 deletions(-)
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 1f1ec361089b3..529ffa5e7b452 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -8243,14 +8243,12 @@ static ssize_t btrfs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
return ret;
}
-#define BTRFS_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC)
-
static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
__u64 start, __u64 len)
{
int ret;
- ret = fiemap_prep(inode, fieinfo, start, &len, BTRFS_FIEMAP_FLAGS);
+ ret = fiemap_prep(inode, fieinfo, start, &len, 0);
if (ret)
return ret;
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index 8a2e94931dc96..32880fca6d8d8 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -3408,8 +3408,7 @@ static int smb3_fiemap(struct cifs_tcon *tcon,
int i, num, rc, flags, last_blob;
u64 next;
- rc = fiemap_prep(cfile->dentry->d_inode, fei, start, &len,
- FIEMAP_FLAG_SYNC);
+ rc = fiemap_prep(cfile->dentry->d_inode, fei, start, &len, 0);
if (rc)
rc;
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 41f73dea92cac..93574e88f6543 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -4908,7 +4908,7 @@ int ext4_get_es_cache(struct inode *inode, struct fiemap_extent_info *fieinfo,
fieinfo->fi_flags &= ~FIEMAP_FLAG_CACHE;
}
- error = fiemap_prep(inode, fieinfo, start, &len, FIEMAP_FLAG_SYNC);
+ error = fiemap_prep(inode, fieinfo, start, &len, 0);
if (error)
return error;
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 03faafc591b17..9de7dc476ed16 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -1825,8 +1825,7 @@ int f2fs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
return ret;
}
- ret = fiemap_prep(inode, fieinfo, start, &len,
- FIEMAP_FLAG_SYNC | FIEMAP_FLAG_XATTR);
+ ret = fiemap_prep(inode, fieinfo, start, &len, FIEMAP_FLAG_XATTR);
if (ret)
return ret;
diff --git a/fs/ioctl.c b/fs/ioctl.c
index 4d94c20c9596b..ae0d228d18a16 100644
--- a/fs/ioctl.c
+++ b/fs/ioctl.c
@@ -162,6 +162,7 @@ int fiemap_prep(struct inode *inode, struct fiemap_extent_info *fieinfo,
{
u64 maxbytes = inode->i_sb->s_maxbytes;
u32 incompat_flags;
+ int ret = 0;
if (*len == 0)
return -EINVAL;
@@ -174,13 +175,17 @@ int fiemap_prep(struct inode *inode, struct fiemap_extent_info *fieinfo,
if (*len > maxbytes || (maxbytes - *len) < start)
*len = maxbytes - start;
+ supported_flags |= FIEMAP_FLAG_SYNC;
supported_flags &= FIEMAP_FLAGS_COMPAT;
incompat_flags = fieinfo->fi_flags & ~supported_flags;
if (incompat_flags) {
fieinfo->fi_flags = incompat_flags;
return -EBADR;
}
- return 0;
+
+ if (fieinfo->fi_flags & FIEMAP_FLAG_SYNC)
+ ret = filemap_write_and_wait(inode->i_mapping);
+ return ret;
Since we could return an error from here.
I think we should again update the function description that
it could return a negative error value if filemap_write_and_wait()
fails. And also should document this in Documentation/*
}
EXPORT_SYMBOL(fiemap_prep);
@@ -209,9 +214,6 @@ static int ioctl_fiemap(struct file *filp, struct fiemap __user *ufiemap)
fieinfo.fi_extents_max * sizeof(struct fiemap_extent)))
return -EFAULT;
- if (fieinfo.fi_flags & FIEMAP_FLAG_SYNC)
- filemap_write_and_wait(inode->i_mapping);
-
error = inode->i_op->fiemap(inode, &fieinfo, fiemap.fm_start,
fiemap.fm_length);
fiemap.fm_flags = fieinfo.fi_flags;
diff --git a/fs/iomap/fiemap.c b/fs/iomap/fiemap.c
index 5e4e3520424da..fffd9eedfd880 100644
--- a/fs/iomap/fiemap.c
+++ b/fs/iomap/fiemap.c
@@ -75,16 +75,10 @@ int iomap_fiemap(struct inode *inode, struct fiemap_extent_info *fi,
ctx.fi = fi;
ctx.prev.type = IOMAP_HOLE;
- ret = fiemap_prep(inode, fi, start, &len, FIEMAP_FLAG_SYNC);
+ ret = fiemap_prep(inode, fi, start, &len, 0);
if (ret)
return ret;
- if (fi->fi_flags & FIEMAP_FLAG_SYNC) {
- ret = filemap_write_and_wait(inode->i_mapping);
- if (ret)
- return ret;
- }
-
while (len > 0) {
ret = iomap_apply(inode, start, len, IOMAP_REPORT, ops, &ctx,
iomap_fiemap_actor);
diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c
index 052c2da11e4d7..25b0d368ecdb2 100644
--- a/fs/nilfs2/inode.c
+++ b/fs/nilfs2/inode.c
@@ -1006,7 +1006,7 @@ int nilfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
unsigned int blkbits = inode->i_blkbits;
int ret, n;
- ret = fiemap_prep(inode, fieinfo, start, &len, FIEMAP_FLAG_SYNC);
+ ret = fiemap_prep(inode, fieinfo, start, &len, 0);
if (ret)
return ret;
diff --git a/fs/ocfs2/extent_map.c b/fs/ocfs2/extent_map.c
index 3744179b73fa1..a94852af5510d 100644
--- a/fs/ocfs2/extent_map.c
+++ b/fs/ocfs2/extent_map.c
@@ -733,8 +733,6 @@ static int ocfs2_fiemap_inline(struct inode *inode, struct buffer_head *di_bh,
return 0;
}
-#define OCFS2_FIEMAP_FLAGS (FIEMAP_FLAG_SYNC)
-
int ocfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
u64 map_start, u64 map_len)
{
@@ -746,8 +744,7 @@ int ocfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
struct buffer_head *di_bh = NULL;
struct ocfs2_extent_rec rec;
- ret = fiemap_prep(inode, fieinfo, map_start, &map_len,
- OCFS2_FIEMAP_FLAGS);
+ ret = fiemap_prep(inode, fieinfo, map_start, &map_len, 0);
if (ret)
return ret;
diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
index b5fec34105569..c7cb883c47b86 100644
--- a/fs/overlayfs/inode.c
+++ b/fs/overlayfs/inode.c
@@ -462,10 +462,6 @@ static int ovl_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
return -EOPNOTSUPP;
old_cred = ovl_override_creds(inode->i_sb);
-
- if (fieinfo->fi_flags & FIEMAP_FLAG_SYNC)
- filemap_write_and_wait(realinode->i_mapping);
-
err = realinode->i_op->fiemap(realinode, fieinfo, start, len);
revert_creds(old_cred);
