Skip to content

Commit

Permalink
CIFS: Move r/wsize negotiating to ops struct
Browse files Browse the repository at this point in the history 
Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
  • Loading branch information
Pavel Shilovsky authored and Steve French committed Sep 25, 2012
1 parent 7a5cfb1 commit 24985c5
Show file tree
Hide file tree
Showing 3 changed files with 149 additions and 142 deletions.
61 changes: 61 additions & 0 deletions fs/cifs/cifsglob.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -213,6 +213,10 @@ struct smb_version_operations {
bool (*need_neg)(struct TCP_Server_Info *);
/* negotiate to the server */
int (*negotiate)(const unsigned int, struct cifs_ses *);
/* set negotiated write size */
unsigned int (*negotiate_wsize)(struct cifs_tcon *, struct smb_vol *);
/* set negotiated read size */
unsigned int (*negotiate_rsize)(struct cifs_tcon *, struct smb_vol *);
/* setup smb sessionn */
int (*sess_setup)(const unsigned int, struct cifs_ses *,
const struct nls_table *);
Expand Down Expand Up @@ -515,6 +519,63 @@ get_next_mid(struct TCP_Server_Info *server)
return server->ops->get_next_mid(server);
}

/*
* When the server supports very large reads and writes via POSIX extensions,
* we can allow up to 2^24-1, minus the size of a READ/WRITE_AND_X header, not
* including the RFC1001 length.
*
* Note that this might make for "interesting" allocation problems during
* writeback however as we have to allocate an array of pointers for the
* pages. A 16M write means ~32kb page array with PAGE_CACHE_SIZE == 4096.
*
* For reads, there is a similar problem as we need to allocate an array
* of kvecs to handle the receive, though that should only need to be done
* once.
*/
#define CIFS_MAX_WSIZE ((1<<24) - 1 - sizeof(WRITE_REQ) + 4)
#define CIFS_MAX_RSIZE ((1<<24) - sizeof(READ_RSP) + 4)

/*
* When the server doesn't allow large posix writes, only allow a rsize/wsize
* of 2^17-1 minus the size of the call header. That allows for a read or
* write up to the maximum size described by RFC1002.
*/
#define CIFS_MAX_RFC1002_WSIZE ((1<<17) - 1 - sizeof(WRITE_REQ) + 4)
#define CIFS_MAX_RFC1002_RSIZE ((1<<17) - 1 - sizeof(READ_RSP) + 4)

/*
* The default wsize is 1M. find_get_pages seems to return a maximum of 256
* pages in a single call. With PAGE_CACHE_SIZE == 4k, this means we can fill
* a single wsize request with a single call.
*/
#define CIFS_DEFAULT_IOSIZE (1024 * 1024)

/*
* Windows only supports a max of 60kb reads and 65535 byte writes. Default to
* those values when posix extensions aren't in force. In actuality here, we
* use 65536 to allow for a write that is a multiple of 4k. Most servers seem
* to be ok with the extra byte even though Windows doesn't send writes that
* are that large.
*
* Citation:
*
* http://blogs.msdn.com/b/openspecification/archive/2009/04/10/smb-maximum-transmit-buffer-size-and-performance-tuning.aspx
*/
#define CIFS_DEFAULT_NON_POSIX_RSIZE (60 * 1024)
#define CIFS_DEFAULT_NON_POSIX_WSIZE (65536)

/*
* On hosts with high memory, we can't currently support wsize/rsize that are
* larger than we can kmap at once. Cap the rsize/wsize at
* LAST_PKMAP * PAGE_SIZE. We'll never be able to fill a read or write request
* larger than that anyway.
*/
#ifdef CONFIG_HIGHMEM
#define CIFS_KMAP_SIZE_LIMIT (LAST_PKMAP * PAGE_CACHE_SIZE)
#else /* CONFIG_HIGHMEM */
#define CIFS_KMAP_SIZE_LIMIT (1<<24)
#endif /* CONFIG_HIGHMEM */

/*
* Macros to allow the TCP_Server_Info->net field and related code to drop out
* when CONFIG_NET_NS isn't set.
Expand Down
144 changes: 2 additions & 142 deletions fs/cifs/connect.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -3261,146 +3261,6 @@ void cifs_setup_cifs_sb(struct smb_vol *pvolume_info,
"mount option supported");
}

/*
* When the server supports very large reads and writes via POSIX extensions,
* we can allow up to 2^24-1, minus the size of a READ/WRITE_AND_X header, not
* including the RFC1001 length.
*
* Note that this might make for "interesting" allocation problems during
* writeback however as we have to allocate an array of pointers for the
* pages. A 16M write means ~32kb page array with PAGE_CACHE_SIZE == 4096.
*
* For reads, there is a similar problem as we need to allocate an array
* of kvecs to handle the receive, though that should only need to be done
* once.
*/
#define CIFS_MAX_WSIZE ((1<<24) - 1 - sizeof(WRITE_REQ) + 4)
#define CIFS_MAX_RSIZE ((1<<24) - sizeof(READ_RSP) + 4)

/*
* When the server doesn't allow large posix writes, only allow a rsize/wsize
* of 2^17-1 minus the size of the call header. That allows for a read or
* write up to the maximum size described by RFC1002.
*/
#define CIFS_MAX_RFC1002_WSIZE ((1<<17) - 1 - sizeof(WRITE_REQ) + 4)
#define CIFS_MAX_RFC1002_RSIZE ((1<<17) - 1 - sizeof(READ_RSP) + 4)

/*
* The default wsize is 1M. find_get_pages seems to return a maximum of 256
* pages in a single call. With PAGE_CACHE_SIZE == 4k, this means we can fill
* a single wsize request with a single call.
*/
#define CIFS_DEFAULT_IOSIZE (1024 * 1024)

/*
* Windows only supports a max of 60kb reads and 65535 byte writes. Default to
* those values when posix extensions aren't in force. In actuality here, we
* use 65536 to allow for a write that is a multiple of 4k. Most servers seem
* to be ok with the extra byte even though Windows doesn't send writes that
* are that large.
*
* Citation:
*
* http://blogs.msdn.com/b/openspecification/archive/2009/04/10/smb-maximum-transmit-buffer-size-and-performance-tuning.aspx
*/
#define CIFS_DEFAULT_NON_POSIX_RSIZE (60 * 1024)
#define CIFS_DEFAULT_NON_POSIX_WSIZE (65536)

/*
* On hosts with high memory, we can't currently support wsize/rsize that are
* larger than we can kmap at once. Cap the rsize/wsize at
* LAST_PKMAP * PAGE_SIZE. We'll never be able to fill a read or write request
* larger than that anyway.
*/
#ifdef CONFIG_HIGHMEM
#define CIFS_KMAP_SIZE_LIMIT (LAST_PKMAP * PAGE_CACHE_SIZE)
#else /* CONFIG_HIGHMEM */
#define CIFS_KMAP_SIZE_LIMIT (1<<24)
#endif /* CONFIG_HIGHMEM */

static unsigned int
cifs_negotiate_wsize(struct cifs_tcon *tcon, struct smb_vol *pvolume_info)
{
__u64 unix_cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
struct TCP_Server_Info *server = tcon->ses->server;
unsigned int wsize;

/* start with specified wsize, or default */
if (pvolume_info->wsize)
wsize = pvolume_info->wsize;
else if (tcon->unix_ext && (unix_cap & CIFS_UNIX_LARGE_WRITE_CAP))
wsize = CIFS_DEFAULT_IOSIZE;
else
wsize = CIFS_DEFAULT_NON_POSIX_WSIZE;

/* can server support 24-bit write sizes? (via UNIX extensions) */
if (!tcon->unix_ext || !(unix_cap & CIFS_UNIX_LARGE_WRITE_CAP))
wsize = min_t(unsigned int, wsize, CIFS_MAX_RFC1002_WSIZE);

/*
* no CAP_LARGE_WRITE_X or is signing enabled without CAP_UNIX set?
* Limit it to max buffer offered by the server, minus the size of the
* WRITEX header, not including the 4 byte RFC1001 length.
*/
if (!(server->capabilities & CAP_LARGE_WRITE_X) ||
(!(server->capabilities & CAP_UNIX) &&
(server->sec_mode & (SECMODE_SIGN_ENABLED|SECMODE_SIGN_REQUIRED))))
wsize = min_t(unsigned int, wsize,
server->maxBuf - sizeof(WRITE_REQ) + 4);

/* limit to the amount that we can kmap at once */
wsize = min_t(unsigned int, wsize, CIFS_KMAP_SIZE_LIMIT);

/* hard limit of CIFS_MAX_WSIZE */
wsize = min_t(unsigned int, wsize, CIFS_MAX_WSIZE);

return wsize;
}

static unsigned int
cifs_negotiate_rsize(struct cifs_tcon *tcon, struct smb_vol *pvolume_info)
{
__u64 unix_cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
struct TCP_Server_Info *server = tcon->ses->server;
unsigned int rsize, defsize;

/*
* Set default value...
*
* HACK alert! Ancient servers have very small buffers. Even though
* MS-CIFS indicates that servers are only limited by the client's
* bufsize for reads, testing against win98se shows that it throws
* INVALID_PARAMETER errors if you try to request too large a read.
* OS/2 just sends back short reads.
*
* If the server doesn't advertise CAP_LARGE_READ_X, then assume that
* it can't handle a read request larger than its MaxBufferSize either.
*/
if (tcon->unix_ext && (unix_cap & CIFS_UNIX_LARGE_READ_CAP))
defsize = CIFS_DEFAULT_IOSIZE;
else if (server->capabilities & CAP_LARGE_READ_X)
defsize = CIFS_DEFAULT_NON_POSIX_RSIZE;
else
defsize = server->maxBuf - sizeof(READ_RSP);

rsize = pvolume_info->rsize ? pvolume_info->rsize : defsize;

/*
* no CAP_LARGE_READ_X? Then MS-CIFS states that we must limit this to
* the client's MaxBufferSize.
*/
if (!(server->capabilities & CAP_LARGE_READ_X))
rsize = min_t(unsigned int, CIFSMaxBufSize, rsize);

/* limit to the amount that we can kmap at once */
rsize = min_t(unsigned int, rsize, CIFS_KMAP_SIZE_LIMIT);

/* hard limit of CIFS_MAX_RSIZE */
rsize = min_t(unsigned int, rsize, CIFS_MAX_RSIZE);

return rsize;
}

static void
cleanup_volume_info_contents(struct smb_vol *volume_info)
{
Expand Down Expand Up @@ -3651,8 +3511,8 @@ cifs_mount(struct cifs_sb_info *cifs_sb, struct smb_vol *volume_info)
if (!tcon->ipc && server->ops->qfs_tcon)
server->ops->qfs_tcon(xid, tcon);

cifs_sb->wsize = cifs_negotiate_wsize(tcon, volume_info);
cifs_sb->rsize = cifs_negotiate_rsize(tcon, volume_info);
cifs_sb->wsize = server->ops->negotiate_wsize(tcon, volume_info);
cifs_sb->rsize = server->ops->negotiate_rsize(tcon, volume_info);

/* tune readahead according to rsize */
cifs_sb->bdi.ra_pages = cifs_sb->rsize / PAGE_CACHE_SIZE;
Expand Down
86 changes: 86 additions & 0 deletions fs/cifs/smb1ops.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -17,6 +17,7 @@
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/

#include <linux/pagemap.h>
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_debug.h"
Expand Down Expand Up @@ -410,6 +411,89 @@ cifs_negotiate(const unsigned int xid, struct cifs_ses *ses)
return rc;
}

static unsigned int
cifs_negotiate_wsize(struct cifs_tcon *tcon, struct smb_vol *volume_info)
{
__u64 unix_cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
struct TCP_Server_Info *server = tcon->ses->server;
unsigned int wsize;

/* start with specified wsize, or default */
if (volume_info->wsize)
wsize = volume_info->wsize;
else if (tcon->unix_ext && (unix_cap & CIFS_UNIX_LARGE_WRITE_CAP))
wsize = CIFS_DEFAULT_IOSIZE;
else
wsize = CIFS_DEFAULT_NON_POSIX_WSIZE;

/* can server support 24-bit write sizes? (via UNIX extensions) */
if (!tcon->unix_ext || !(unix_cap & CIFS_UNIX_LARGE_WRITE_CAP))
wsize = min_t(unsigned int, wsize, CIFS_MAX_RFC1002_WSIZE);

/*
* no CAP_LARGE_WRITE_X or is signing enabled without CAP_UNIX set?
* Limit it to max buffer offered by the server, minus the size of the
* WRITEX header, not including the 4 byte RFC1001 length.
*/
if (!(server->capabilities & CAP_LARGE_WRITE_X) ||
(!(server->capabilities & CAP_UNIX) &&
(server->sec_mode & (SECMODE_SIGN_ENABLED|SECMODE_SIGN_REQUIRED))))
wsize = min_t(unsigned int, wsize,
server->maxBuf - sizeof(WRITE_REQ) + 4);

/* limit to the amount that we can kmap at once */
wsize = min_t(unsigned int, wsize, CIFS_KMAP_SIZE_LIMIT);

/* hard limit of CIFS_MAX_WSIZE */
wsize = min_t(unsigned int, wsize, CIFS_MAX_WSIZE);

return wsize;
}

static unsigned int
cifs_negotiate_rsize(struct cifs_tcon *tcon, struct smb_vol *volume_info)
{
__u64 unix_cap = le64_to_cpu(tcon->fsUnixInfo.Capability);
struct TCP_Server_Info *server = tcon->ses->server;
unsigned int rsize, defsize;

/*
* Set default value...
*
* HACK alert! Ancient servers have very small buffers. Even though
* MS-CIFS indicates that servers are only limited by the client's
* bufsize for reads, testing against win98se shows that it throws
* INVALID_PARAMETER errors if you try to request too large a read.
* OS/2 just sends back short reads.
*
* If the server doesn't advertise CAP_LARGE_READ_X, then assume that
* it can't handle a read request larger than its MaxBufferSize either.
*/
if (tcon->unix_ext && (unix_cap & CIFS_UNIX_LARGE_READ_CAP))
defsize = CIFS_DEFAULT_IOSIZE;
else if (server->capabilities & CAP_LARGE_READ_X)
defsize = CIFS_DEFAULT_NON_POSIX_RSIZE;
else
defsize = server->maxBuf - sizeof(READ_RSP);

rsize = volume_info->rsize ? volume_info->rsize : defsize;

/*
* no CAP_LARGE_READ_X? Then MS-CIFS states that we must limit this to
* the client's MaxBufferSize.
*/
if (!(server->capabilities & CAP_LARGE_READ_X))
rsize = min_t(unsigned int, CIFSMaxBufSize, rsize);

/* limit to the amount that we can kmap at once */
rsize = min_t(unsigned int, rsize, CIFS_KMAP_SIZE_LIMIT);

/* hard limit of CIFS_MAX_RSIZE */
rsize = min_t(unsigned int, rsize, CIFS_MAX_RSIZE);

return rsize;
}

static void
cifs_qfs_tcon(const unsigned int xid, struct cifs_tcon *tcon)
{
Expand Down Expand Up @@ -678,6 +762,8 @@ struct smb_version_operations smb1_operations = {
.check_trans2 = cifs_check_trans2,
.need_neg = cifs_need_neg,
.negotiate = cifs_negotiate,
.negotiate_wsize = cifs_negotiate_wsize,
.negotiate_rsize = cifs_negotiate_rsize,
.sess_setup = CIFS_SessSetup,
.logoff = CIFSSMBLogoff,
.tree_connect = CIFSTCon,
Expand Down

0 comments on commit 24985c5

Please sign in to comment.