CIFS: Fix rsize usage for sync read

If a server changes maximum buffer size for read requests (rsize)
on reconnect we can fail on repeating with a big size buffer on
-EAGAIN error in cifs_read. Fix this by checking rsize all the
time before repeating requests.

Reviewed-by: Shirish Pargaonkar <spargaonkar@suse.com>
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
This commit is contained in:
Pavel Shilovsky 2014-06-25 16:19:02 +04:00 committed by Steve French
parent 25f402598d
commit e374d90f8a

View file

@ -3148,18 +3148,19 @@ cifs_read(struct file *file, char *read_data, size_t read_size, loff_t *offset)
for (total_read = 0, cur_offset = read_data; read_size > total_read;
total_read += bytes_read, cur_offset += bytes_read) {
current_read_size = min_t(uint, read_size - total_read, rsize);
/*
* For windows me and 9x we do not want to request more than it
* negotiated since it will refuse the read then.
*/
if ((tcon->ses) && !(tcon->ses->capabilities &
do {
current_read_size = min_t(uint, read_size - total_read,
rsize);
/*
* For windows me and 9x we do not want to request more
* than it negotiated since it will refuse the read
* then.
*/
if ((tcon->ses) && !(tcon->ses->capabilities &
tcon->ses->server->vals->cap_large_files)) {
current_read_size = min_t(uint, current_read_size,
CIFSMaxBufSize);
}
rc = -EAGAIN;
while (rc == -EAGAIN) {
current_read_size = min_t(uint,
current_read_size, CIFSMaxBufSize);
}
if (open_file->invalidHandle) {
rc = cifs_reopen_file(open_file, true);
if (rc != 0)
@ -3172,7 +3173,8 @@ cifs_read(struct file *file, char *read_data, size_t read_size, loff_t *offset)
rc = server->ops->sync_read(xid, open_file, &io_parms,
&bytes_read, &cur_offset,
&buf_type);
}
} while (rc == -EAGAIN);
if (rc || (bytes_read == 0)) {
if (total_read) {
break;