diff options
| author | David Howells <dhowells@redhat.com> | 2021-02-04 00:15:21 -0600 |
|---|---|---|
| committer | Steve French <stfrench@microsoft.com> | 2021-02-25 19:08:06 -0600 |
| commit | cf0604a686b11175d8beae60281c4ccc95aaa5c2 (patch) | |
| tree | 62ad782990865ba28f748e9e780925e1cc7a7693 | |
| parent | 5ff2836ed3a5c24420a7235be25a462594cdc4ea (diff) | |
| download | linux-leds-cf0604a686b11175d8beae60281c4ccc95aaa5c2.tar.gz | |
cifs: use discard iterator to discard unneeded network data more efficiently
The iterator, ITER_DISCARD, that can only be used in READ mode and
just discards any data copied to it, was added to allow a network
filesystem to discard any unwanted data sent by a server.
Convert cifs_discard_from_socket() to use this.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
| -rw-r--r-- | fs/cifs/cifsproto.h | 2 | ||||
| -rw-r--r-- | fs/cifs/cifssmb.c | 6 | ||||
| -rw-r--r-- | fs/cifs/connect.c | 17 |
3 files changed, 22 insertions, 3 deletions
diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h index 32f7a013402ee8..75ce6f742b8d76 100644 --- a/fs/cifs/cifsproto.h +++ b/fs/cifs/cifsproto.h @@ -232,6 +232,8 @@ extern unsigned int setup_special_user_owner_ACE(struct cifs_ace *pace); extern void dequeue_mid(struct mid_q_entry *mid, bool malformed); extern int cifs_read_from_socket(struct TCP_Server_Info *server, char *buf, unsigned int to_read); +extern ssize_t cifs_discard_from_socket(struct TCP_Server_Info *server, + size_t to_read); extern int cifs_read_page_from_socket(struct TCP_Server_Info *server, struct page *page, unsigned int page_offset, diff --git a/fs/cifs/cifssmb.c b/fs/cifs/cifssmb.c index 0496934feecb77..c279527aae92d3 100644 --- a/fs/cifs/cifssmb.c +++ b/fs/cifs/cifssmb.c @@ -1451,9 +1451,9 @@ cifs_discard_remaining_data(struct TCP_Server_Info *server) while (remaining > 0) { int length; - length = cifs_read_from_socket(server, server->bigbuf, - min_t(unsigned int, remaining, - CIFSMaxBufSize + MAX_HEADER_SIZE(server))); + length = cifs_discard_from_socket(server, + min_t(size_t, remaining, + CIFSMaxBufSize + MAX_HEADER_SIZE(server))); if (length < 0) return length; server->total_read += length; diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index b2447cea45aeba..112692300fb60a 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -564,6 +564,23 @@ cifs_read_from_socket(struct TCP_Server_Info *server, char *buf, return cifs_readv_from_socket(server, &smb_msg); } +ssize_t +cifs_discard_from_socket(struct TCP_Server_Info *server, size_t to_read) +{ + struct msghdr smb_msg; + + /* + * iov_iter_discard already sets smb_msg.type and count and iov_offset + * and cifs_readv_from_socket sets msg_control and msg_controllen + * so little to initialize in struct msghdr + */ + smb_msg.msg_name = NULL; + smb_msg.msg_namelen = 0; + iov_iter_discard(&smb_msg.msg_iter, READ, to_read); + + return cifs_readv_from_socket(server, &smb_msg); +} + int cifs_read_page_from_socket(struct TCP_Server_Info *server, struct page *page, unsigned int page_offset, unsigned int to_read) |