cifs: add support for SEEK_DATA and SEEK_HOLE

Add llseek op for SEEK_DATA and SEEK_HOLE.
Improves xfstests/285,286,436,445,448 and 490

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This commit is contained in:
Ronnie Sahlberg 2019-05-15 07:17:02 +10:00 committed by Steve French
parent 9ab70ca653
commit dece44e381
3 changed files with 99 additions and 0 deletions

View File

@ -878,6 +878,9 @@ static ssize_t cifs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
static loff_t cifs_llseek(struct file *file, loff_t offset, int whence)
{
struct cifsFileInfo *cfile = file->private_data;
struct cifs_tcon *tcon;
/*
* whence == SEEK_END || SEEK_DATA || SEEK_HOLE => we must revalidate
* the cached file length
@ -909,6 +912,12 @@ static loff_t cifs_llseek(struct file *file, loff_t offset, int whence)
if (rc < 0)
return (loff_t)rc;
}
if (cfile && cfile->tlink) {
tcon = tlink_tcon(cfile->tlink);
if (tcon->ses->server->ops->llseek)
return tcon->ses->server->ops->llseek(file, tcon,
offset, whence);
}
return generic_file_llseek(file, offset, whence);
}

View File

@ -497,6 +497,8 @@ struct smb_version_operations {
/* version specific fiemap implementation */
int (*fiemap)(struct cifs_tcon *tcon, struct cifsFileInfo *,
struct fiemap_extent_info *, u64, u64);
/* version specific llseek implementation */
loff_t (*llseek)(struct file *, struct cifs_tcon *, loff_t, int);
};
struct smb_version_values {

View File

@ -2922,6 +2922,90 @@ static long smb3_simple_falloc(struct file *file, struct cifs_tcon *tcon,
return rc;
}
static loff_t smb3_llseek(struct file *file, struct cifs_tcon *tcon, loff_t offset, int whence)
{
struct cifsFileInfo *wrcfile, *cfile = file->private_data;
struct cifsInodeInfo *cifsi;
struct inode *inode;
int rc = 0;
struct file_allocated_range_buffer in_data, *out_data = NULL;
u32 out_data_len;
unsigned int xid;
if (whence != SEEK_HOLE && whence != SEEK_DATA)
return generic_file_llseek(file, offset, whence);
inode = d_inode(cfile->dentry);
cifsi = CIFS_I(inode);
if (offset < 0 || offset >= i_size_read(inode))
return -ENXIO;
xid = get_xid();
/*
* We need to be sure that all dirty pages are written as they
* might fill holes on the server.
* Note that we also MUST flush any written pages since at least
* some servers (Windows2016) will not reflect recent writes in
* QUERY_ALLOCATED_RANGES until SMB2_flush is called.
*/
wrcfile = find_writable_file(cifsi, false);
if (wrcfile) {
filemap_write_and_wait(inode->i_mapping);
smb2_flush_file(xid, tcon, &wrcfile->fid);
cifsFileInfo_put(wrcfile);
}
if (!(cifsi->cifsAttrs & FILE_ATTRIBUTE_SPARSE_FILE)) {
if (whence == SEEK_HOLE)
offset = i_size_read(inode);
goto lseek_exit;
}
in_data.file_offset = cpu_to_le64(offset);
in_data.length = cpu_to_le64(i_size_read(inode));
rc = SMB2_ioctl(xid, tcon, cfile->fid.persistent_fid,
cfile->fid.volatile_fid,
FSCTL_QUERY_ALLOCATED_RANGES, true,
(char *)&in_data, sizeof(in_data),
sizeof(struct file_allocated_range_buffer),
(char **)&out_data, &out_data_len);
if (rc == -E2BIG)
rc = 0;
if (rc)
goto lseek_exit;
if (whence == SEEK_HOLE && out_data_len == 0)
goto lseek_exit;
if (whence == SEEK_DATA && out_data_len == 0) {
rc = -ENXIO;
goto lseek_exit;
}
if (out_data_len < sizeof(struct file_allocated_range_buffer)) {
rc = -EINVAL;
goto lseek_exit;
}
if (whence == SEEK_DATA) {
offset = le64_to_cpu(out_data->file_offset);
goto lseek_exit;
}
if (offset < le64_to_cpu(out_data->file_offset))
goto lseek_exit;
offset = le64_to_cpu(out_data->file_offset) + le64_to_cpu(out_data->length);
lseek_exit:
free_xid(xid);
kfree(out_data);
if (!rc)
return vfs_setpos(file, offset, inode->i_sb->s_maxbytes);
else
return rc;
}
static int smb3_fiemap(struct cifs_tcon *tcon,
struct cifsFileInfo *cfile,
struct fiemap_extent_info *fei, u64 start, u64 len)
@ -4166,6 +4250,7 @@ struct smb_version_operations smb20_operations = {
.ioctl_query_info = smb2_ioctl_query_info,
.make_node = smb2_make_node,
.fiemap = smb3_fiemap,
.llseek = smb3_llseek,
};
struct smb_version_operations smb21_operations = {
@ -4266,6 +4351,7 @@ struct smb_version_operations smb21_operations = {
.ioctl_query_info = smb2_ioctl_query_info,
.make_node = smb2_make_node,
.fiemap = smb3_fiemap,
.llseek = smb3_llseek,
};
struct smb_version_operations smb30_operations = {
@ -4375,6 +4461,7 @@ struct smb_version_operations smb30_operations = {
.ioctl_query_info = smb2_ioctl_query_info,
.make_node = smb2_make_node,
.fiemap = smb3_fiemap,
.llseek = smb3_llseek,
};
struct smb_version_operations smb311_operations = {
@ -4485,6 +4572,7 @@ struct smb_version_operations smb311_operations = {
.ioctl_query_info = smb2_ioctl_query_info,
.make_node = smb2_make_node,
.fiemap = smb3_fiemap,
.llseek = smb3_llseek,
};
struct smb_version_values smb20_values = {