fs: handle FIEMAP_FLAG_SYNC in fiemap_prep

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.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Link: https://lore.kernel.org/r/20200523073016.2944131-8-hch@lst.de
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 1f1ec36..529ffa5 100644 (file)
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -8243,14 +8243,12 @@ out:
        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 828e53e..300ade2 100644 (file)
--- 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(d_inode(cfile->dentry), fei, start, &len,
-                       FIEMAP_FLAG_SYNC);
+       rc = fiemap_prep(d_inode(cfile->dentry), fei, start, &len, 0);
        if (rc)
                return rc;
 

diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index cea083e..7d088ff 100644 (file)
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -4938,7 +4938,7 @@ 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/ext4/ioctl.c b/fs/ext4/ioctl.c
index 0746532..f81acbb 100644 (file)
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -759,9 +759,6 @@ static int ext4_ioctl_get_es_cache(struct file *filp, unsigned long arg)
                       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 = ext4_get_es_cache(inode, &fieinfo, fiemap.fm_start,
                        fiemap.fm_length);
        fiemap.fm_flags = fieinfo.fi_flags;

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 03faafc..9de7dc4 100644 (file)
--- 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 56bbf02..b16e962 100644 (file)
--- a/fs/ioctl.c
+++ b/fs/ioctl.c
@@ -166,6 +166,7 @@ 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;
@@ -178,13 +179,17 @@ 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;
 }
 EXPORT_SYMBOL(fiemap_prep);
 
@@ -213,9 +218,6 @@ 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 89dca4a..aab070d 100644 (file)
--- 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 052c2da..25b0d36 100644 (file)
--- 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 3744179..a94852a 100644 (file)
--- 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 b5fec34..c7cb883 100644 (file)
--- 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);