[PATCH 4/4] fs: handle SEEK_HOLE/SEEK_DATA properly in all fs's that define their own llseek

Josef Bacik
2011-06-28T15:33:28Z

This converts everybody to handle SEEK_HOLE/SEEK_DATA properly. In some cases
we just return -EINVAL, in others we do the normal generic thing, and in others
we're simply making sure that the properly due-dilligence is done. For example
in NFS/CIFS we need to make sure the file size is update properly for the
SEEK_HOLE and SEEK_DATA case, but since it calls the generic llseek stuff itself
that is all we have to do. Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
---
fs/block_dev.c | 11 ++++++++---
fs/ceph/dir.c | 8 +++++++-
fs/ceph/file.c | 20 ++++++++++++++++++--
fs/cifs/cifsfs.c | 7 +++++--
fs/fuse/file.c | 21 +++++++++++++++++++--
fs/hpfs/dir.c | 4 ++++
fs/nfs/file.c | 7 +++++--
7 files changed, 66 insertions(+), 12 deletions(-)

diff --git a/fs/block_dev.c b/fs/block_dev.c
index 610e8e0..966617a 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -355,20 +355,25 @@ static loff_t block_llseek(struct file *file, loff_t offset, int origin)
mutex_lock(&bd_inode->i_mutex);
size = i_size_read(bd_inode);

+ retval = -EINVAL;
switch (origin) {
- case 2:
+ case SEEK_END:
offset += size;
break;
- case 1:
+ case SEEK_CUR:
offset += file->f_pos;
+ case SEEK_SET:
+ break;
+ default:
+ goto out;
}
- retval = -EINVAL;
if (offset >= 0 && offset <= size) {
if (offset != file->f_pos) {
file->f_pos = offset;
}
retval = offset;
}
+out:
mutex_unlock(&bd_inode->i_mutex);
return retval;
}
diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index ef8f08c..79cd77c 100644
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -446,14 +446,19 @@ static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int origin)
loff_t retval;

mutex_lock(&inode->i_mutex);
+ retval = -EINVAL;
switch (origin) {
case SEEK_END:
offset += inode->i_size + 2; /* FIXME */
break;
case SEEK_CUR:
offset += file->f_pos;
+ case SEEK_SET:
+ break;
+ default:
+ goto out;
}
- retval = -EINVAL;
+
if (offset >= 0 && offset <= inode->i_sb->s_maxbytes) {
if (offset != file->f_pos) {
file->f_pos = offset;
@@ -477,6 +482,7 @@ static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int origin)
if (offset > old_offset)
fi->dir_release_count--;
}
+out:
mutex_unlock(&inode->i_mutex);
return retval;
}
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 9542f07..774feb1 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -770,13 +770,16 @@ static loff_t ceph_llseek(struct file *file, loff_t offset, int origin)

mutex_lock(&inode->i_mutex);
__ceph_do_pending_vmtruncate(inode);
- switch (origin) {
- case SEEK_END:
+ if (origin != SEEK_CUR || origin != SEEK_SET) {
ret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE);
if (ret < 0) {
offset = ret;
goto out;
}
+ }
+
+ switch (origin) {
+ case SEEK_END:
offset += inode->i_size;
break;
case SEEK_CUR:
@@ -792,6 +795,19 @@ static loff_t ceph_llseek(struct file *file, loff_t offset, int origin)
}
offset += file->f_pos;
break;
+ case SEEK_DATA:
+ if (offset >= inode->i_size) {
+ ret = -ENXIO;
+ goto out;
+ }
+ break;
+ case SEEK_HOLE:
+ if (offset >= inode->i_size) {
+ ret = -ENXIO;
+ goto out;
+ }
+ offset = inode->i_size;
+ break;
}

if (offset < 0 || offset > inode->i_sb->s_maxbytes) {
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 35f9154..5feb6bb 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -746,8 +746,11 @@ static ssize_t cifs_file_aio_write(struct kiocb *iocb, const struct iovec *iov,

static loff_t cifs_llseek(struct file *file, loff_t offset, int origin)
{
- /* origin == SEEK_END => we must revalidate the cached file length */
- if (origin == SEEK_END) {
+ /*
+ * origin == SEEK_END || SEEK_DATA || SEEK_HOLE => we must revalidate
+ * the cached file length
+ */
+ if (origin != SEEK_SET || origin != SEEK_CUR) {
int rc;
struct inode *inode = file->f_path.dentry->d_inode;

diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 82a6646..73b89df 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -1600,15 +1600,32 @@ static loff_t fuse_file_llseek(struct file *file, loff_t offset, int origin)
struct inode *inode = file->f_path.dentry->d_inode;

mutex_lock(&inode->i_mutex);
- switch (origin) {
- case SEEK_END:
+ if (origin != SEEK_CUR || origin != SEEK_SET) {
retval = fuse_update_attributes(inode, NULL, file, NULL);
if (retval)
goto exit;
+ }
+
+ switch (origin) {
+ case SEEK_END:
offset += i_size_read(inode);
break;
case SEEK_CUR:
offset += file->f_pos;
+ break;
+ case SEEK_DATA:
+ if (offset >= i_size_read(inode)) {
+ retval = -ENXIO;
+ goto exit;
+ }
+ break;
+ case SEEK_HOLE:
+ if (offset >= i_size_read(inode)) {
+ retval = -ENXIO;
+ goto exit;
+ }
+ offset = i_size_read(inode);
+ break;
}
retval = -EINVAL;
if (offset >= 0 && offset <= inode->i_sb->s_maxbytes) {
diff --git a/fs/hpfs/dir.c b/fs/hpfs/dir.c
index f46ae02..96a8ed9 100644
--- a/fs/hpfs/dir.c
+++ b/fs/hpfs/dir.c
@@ -29,6 +29,10 @@ static loff_t hpfs_dir_lseek(struct file *filp, loff_t off, int whence)
struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
struct super_block *s = i->i_sb;

+ /* Somebody else will have to figure out what to do here */
+ if (whence == SEEK_DATA || whence == SEEK_HOLE)
+ return -EINVAL;
+
hpfs_lock(s);

/*printk("dir lseek\n");*/
diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index 2f093ed..2c1705b 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -187,8 +187,11 @@ static loff_t nfs_file_llseek(struct file *filp, loff_t offset, int origin)
filp->f_path.dentry->d_name.name,
offset, origin);

- /* origin == SEEK_END => we must revalidate the cached file length */
- if (origin == SEEK_END) {
+ /*
+ * origin == SEEK_END || SEEK_DATA || SEEK_HOLE => we must revalidate
+ * the cached file length
+ */
+ if (origin != SEEK_SET || origin != SEEK_CUR) {
struct inode *inode = filp->f_mapping->host;

int retval = nfs_revalidate_file_size(inode, filp);
--
1.7.5.2