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

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>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

7 files changed, 66 insertions, 12 deletions

diff --git a/fs/block_dev.c b/fs/block_dev.c
index 610e8e0b04b8..966617a422d9 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 e8477dc51b45..0972b457a03f 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 0a292459c895..0d0eae05598f 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -768,13 +768,16 @@ 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:
@@ -790,6 +793,19 @@ 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 cbbb55e781d3..865517470967 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -704,8 +704,11 @@ 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 82a66466a24c..73b89df20851 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 f46ae025bfb5..96a8ed91cedd 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 2f093ed16980..2c1705b6acd7 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);