On some filesystems calling i_op->fiemap() takes the i_mutex,
on others it doesn't. For example, on ext2/ext3 fiemap calls
generic_block_fiemap(), which takes the i_mutex, but on ext4
it doesn't call generic_block_fiemap() for inodes, that have no
extents and does not take the i_mutex in other cases. Other i_op
functions, like setxattr/setattr, rely on the caller to lock the
i_mutex.
This patch moves the i_mutex locking from generic_block_fiemap()
to ioctl_fiemap(), which is currently the only caller of i_op->fiemap().
This change is needed in preparation for EVM to include a hash of
the extent data to be used in the HMAC calculation. EVM is called
when the i_mutex has already been taken.
Signed-off-by: Dmitry Kasatkin <dmitry.kasatkin@xxxxxxxxx>
---
fs/ext2/inode.c | 4 ++--
fs/ext3/inode.c | 4 ++--
fs/ext4/extents.c | 4 ++--
fs/gfs2/inode.c | 3 ---
fs/ioctl.c | 2 ++
5 files changed, 8 insertions(+), 9 deletions(-)
diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
index 6363ac6..0e7a0b3 100644
--- a/fs/ext2/inode.c
+++ b/fs/ext2/inode.c
@@ -760,8 +760,8 @@ int ext2_get_block(struct inode *inode, sector_t iblock, struct buffer_head *bh_
int ext2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
u64 start, u64 len)
{
- return generic_block_fiemap(inode, fieinfo, start, len,
- ext2_get_block);
+ return __generic_block_fiemap(inode, fieinfo, start, len,
+ ext2_get_block);
}
static int ext2_writepage(struct page *page, struct writeback_control *wbc)
diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c
index a075973..0727254 100644
--- a/fs/ext3/inode.c
+++ b/fs/ext3/inode.c
@@ -1046,8 +1046,8 @@ out:
int ext3_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
u64 start, u64 len)
{
- return generic_block_fiemap(inode, fieinfo, start, len,
- ext3_get_block);
+ return __generic_block_fiemap(inode, fieinfo, start, len,
+ ext3_get_block);
}
/*
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index cd0c7ed..e960831 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -4916,8 +4916,8 @@ int ext4_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
/* fallback to generic here if not in extents fmt */
if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)))
- return generic_block_fiemap(inode, fieinfo, start, len,
- ext4_get_block);
+ return __generic_block_fiemap(inode, fieinfo, start, len,
+ ext4_get_block);
if (fiemap_check_flags(fieinfo, EXT4_FIEMAP_FLAGS))
return -EBADR;
diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
index 4ce22e5..bb8d541 100644
--- a/fs/gfs2/inode.c
+++ b/fs/gfs2/inode.c
@@ -1775,8 +1775,6 @@ static int gfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
if (ret)
return ret;
- mutex_lock(&inode->i_mutex);
-
ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
if (ret)
goto out;
@@ -1802,7 +1800,6 @@ static int gfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
gfs2_glock_dq_uninit(&gh);
out:
- mutex_unlock(&inode->i_mutex);
return ret;
}
diff --git a/fs/ioctl.c b/fs/ioctl.c
index 29167be..320993f 100644
--- a/fs/ioctl.c
+++ b/fs/ioctl.c
@@ -206,7 +206,9 @@ static int ioctl_fiemap(struct file *filp, unsigned long arg)
if (fieinfo.fi_flags & FIEMAP_FLAG_SYNC)
filemap_write_and_wait(inode->i_mapping);
+ mutex_lock(&inode->i_mutex);
error = inode->i_op->fiemap(inode, &fieinfo, fiemap.fm_start, len);
+ mutex_unlock(&inode->i_mutex);
fiemap.fm_flags = fieinfo.fi_flags;
fiemap.fm_mapped_extents = fieinfo.fi_extents_mapped;
if (copy_to_user(ufiemap, &fiemap, sizeof(fiemap)))
--
1.7.9.5
--
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