CIFS: Add SMB2 support for cifs_iovec_write

Signed-off-by: Pavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: Steve French <smfrench@gmail.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
This commit is contained in:
Pavel Shilovsky 2012-09-18 16:20:29 -07:00 committed by Steve French
parent c9de5c80d5
commit 3331914125
8 changed files with 206 additions and 44 deletions

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@ -89,6 +89,10 @@ extern mempool_t *cifs_mid_poolp;
struct workqueue_struct *cifsiod_wq;
#ifdef CONFIG_HIGHMEM
DEFINE_MUTEX(cifs_kmap_mutex);
#endif
static int
cifs_read_super(struct super_block *sb)
{

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@ -582,6 +582,33 @@ get_next_mid(struct TCP_Server_Info *server)
#define CIFS_KMAP_SIZE_LIMIT (1<<24)
#endif /* CONFIG_HIGHMEM */
#ifdef CONFIG_HIGHMEM
/*
* On arches that have high memory, kmap address space is limited. By
* serializing the kmap operations on those arches, we ensure that we don't
* end up with a bunch of threads in writeback with partially mapped page
* arrays, stuck waiting for kmap to come back. That situation prevents
* progress and can deadlock.
*/
extern struct mutex cifs_kmap_mutex;
static inline void
cifs_kmap_lock(void)
{
mutex_lock(&cifs_kmap_mutex);
}
static inline void
cifs_kmap_unlock(void)
{
mutex_unlock(&cifs_kmap_mutex);
}
#else /* !CONFIG_HIGHMEM */
#define cifs_kmap_lock() do { ; } while (0)
#define cifs_kmap_unlock() do { ; } while (0)
#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.
@ -891,6 +918,26 @@ struct cifs_readdata {
struct kvec iov[1];
};
struct cifs_writedata;
/* asynchronous write support */
struct cifs_writedata {
struct kref refcount;
struct list_head list;
struct completion done;
enum writeback_sync_modes sync_mode;
struct work_struct work;
struct cifsFileInfo *cfile;
__u64 offset;
pid_t pid;
unsigned int bytes;
int result;
void (*marshal_iov) (struct kvec *iov,
struct cifs_writedata *wdata);
unsigned int nr_pages;
struct page *pages[1];
};
/*
* Take a reference on the file private data. Must be called with
* cifs_file_list_lock held.

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@ -468,24 +468,6 @@ void cifs_readdata_release(struct kref *refcount);
int cifs_async_readv(struct cifs_readdata *rdata);
int cifs_readv_receive(struct TCP_Server_Info *server, struct mid_q_entry *mid);
/* asynchronous write support */
struct cifs_writedata {
struct kref refcount;
struct list_head list;
struct completion done;
enum writeback_sync_modes sync_mode;
struct work_struct work;
struct cifsFileInfo *cfile;
__u64 offset;
pid_t pid;
unsigned int bytes;
int result;
void (*marshal_iov) (struct kvec *iov,
struct cifs_writedata *wdata);
unsigned int nr_pages;
struct page *pages[1];
};
int cifs_async_writev(struct cifs_writedata *wdata);
void cifs_writev_complete(struct work_struct *work);
struct cifs_writedata *cifs_writedata_alloc(unsigned int nr_pages,

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@ -86,32 +86,6 @@ static struct {
#endif /* CONFIG_CIFS_WEAK_PW_HASH */
#endif /* CIFS_POSIX */
#ifdef CONFIG_HIGHMEM
/*
* On arches that have high memory, kmap address space is limited. By
* serializing the kmap operations on those arches, we ensure that we don't
* end up with a bunch of threads in writeback with partially mapped page
* arrays, stuck waiting for kmap to come back. That situation prevents
* progress and can deadlock.
*/
static DEFINE_MUTEX(cifs_kmap_mutex);
static inline void
cifs_kmap_lock(void)
{
mutex_lock(&cifs_kmap_mutex);
}
static inline void
cifs_kmap_unlock(void)
{
mutex_unlock(&cifs_kmap_mutex);
}
#else /* !CONFIG_HIGHMEM */
#define cifs_kmap_lock() do { ; } while(0)
#define cifs_kmap_unlock() do { ; } while(0)
#endif /* CONFIG_HIGHMEM */
/*
* Mark as invalid, all open files on tree connections since they
* were closed when session to server was lost.

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@ -434,6 +434,7 @@ struct smb_version_operations smb21_operations = {
.close = smb2_close_file,
.flush = smb2_flush_file,
.async_readv = smb2_async_readv,
.async_writev = smb2_async_writev,
};
struct smb_version_values smb21_values = {

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@ -33,6 +33,7 @@
#include <linux/vfs.h>
#include <linux/task_io_accounting_ops.h>
#include <linux/uaccess.h>
#include <linux/pagemap.h>
#include <linux/xattr.h>
#include "smb2pdu.h"
#include "cifsglob.h"
@ -1327,3 +1328,125 @@ smb2_async_readv(struct cifs_readdata *rdata)
cifs_small_buf_release(buf);
return rc;
}
/*
* Check the mid_state and signature on received buffer (if any), and queue the
* workqueue completion task.
*/
static void
smb2_writev_callback(struct mid_q_entry *mid)
{
struct cifs_writedata *wdata = mid->callback_data;
struct cifs_tcon *tcon = tlink_tcon(wdata->cfile->tlink);
unsigned int written;
struct smb2_write_rsp *rsp = (struct smb2_write_rsp *)mid->resp_buf;
unsigned int credits_received = 1;
switch (mid->mid_state) {
case MID_RESPONSE_RECEIVED:
credits_received = le16_to_cpu(rsp->hdr.CreditRequest);
wdata->result = smb2_check_receive(mid, tcon->ses->server, 0);
if (wdata->result != 0)
break;
written = le32_to_cpu(rsp->DataLength);
/*
* Mask off high 16 bits when bytes written as returned
* by the server is greater than bytes requested by the
* client. OS/2 servers are known to set incorrect
* CountHigh values.
*/
if (written > wdata->bytes)
written &= 0xFFFF;
if (written < wdata->bytes)
wdata->result = -ENOSPC;
else
wdata->bytes = written;
break;
case MID_REQUEST_SUBMITTED:
case MID_RETRY_NEEDED:
wdata->result = -EAGAIN;
break;
default:
wdata->result = -EIO;
break;
}
if (wdata->result)
cifs_stats_fail_inc(tcon, SMB2_WRITE_HE);
queue_work(cifsiod_wq, &wdata->work);
DeleteMidQEntry(mid);
add_credits(tcon->ses->server, credits_received, 0);
}
/* smb2_async_writev - send an async write, and set up mid to handle result */
int
smb2_async_writev(struct cifs_writedata *wdata)
{
int i, rc = -EACCES;
struct smb2_write_req *req = NULL;
struct cifs_tcon *tcon = tlink_tcon(wdata->cfile->tlink);
struct kvec *iov = NULL;
rc = small_smb2_init(SMB2_WRITE, tcon, (void **) &req);
if (rc)
goto async_writev_out;
/* 1 iov per page + 1 for header */
iov = kzalloc((wdata->nr_pages + 1) * sizeof(*iov), GFP_NOFS);
if (iov == NULL) {
rc = -ENOMEM;
goto async_writev_out;
}
req->hdr.ProcessId = cpu_to_le32(wdata->cfile->pid);
req->PersistentFileId = wdata->cfile->fid.persistent_fid;
req->VolatileFileId = wdata->cfile->fid.volatile_fid;
req->WriteChannelInfoOffset = 0;
req->WriteChannelInfoLength = 0;
req->Channel = 0;
req->Offset = cpu_to_le64(wdata->offset);
/* 4 for rfc1002 length field */
req->DataOffset = cpu_to_le16(
offsetof(struct smb2_write_req, Buffer) - 4);
req->RemainingBytes = 0;
/* 4 for rfc1002 length field and 1 for Buffer */
iov[0].iov_len = get_rfc1002_length(req) + 4 - 1;
iov[0].iov_base = (char *)req;
/*
* This function should marshal up the page array into the kvec
* array, reserving [0] for the header. It should kmap the pages
* and set the iov_len properly for each one. It may also set
* wdata->bytes too.
*/
cifs_kmap_lock();
wdata->marshal_iov(iov, wdata);
cifs_kmap_unlock();
cFYI(1, "async write at %llu %u bytes", wdata->offset, wdata->bytes);
req->Length = cpu_to_le32(wdata->bytes);
inc_rfc1001_len(&req->hdr, wdata->bytes - 1 /* Buffer */);
kref_get(&wdata->refcount);
rc = cifs_call_async(tcon->ses->server, iov, wdata->nr_pages + 1,
NULL, smb2_writev_callback, wdata, 0);
if (rc)
kref_put(&wdata->refcount, cifs_writedata_release);
/* send is done, unmap pages */
for (i = 0; i < wdata->nr_pages; i++)
kunmap(wdata->pages[i]);
async_writev_out:
cifs_small_buf_release(req);
kfree(iov);
return rc;
}

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@ -496,6 +496,36 @@ struct smb2_read_rsp {
__u8 Buffer[1];
} __packed;
/* For write request Flags field below the following flag is defined: */
#define SMB2_WRITEFLAG_WRITE_THROUGH 0x00000001
struct smb2_write_req {
struct smb2_hdr hdr;
__le16 StructureSize; /* Must be 49 */
__le16 DataOffset; /* offset from start of SMB2 header to write data */
__le32 Length;
__le64 Offset;
__u64 PersistentFileId; /* opaque endianness */
__u64 VolatileFileId; /* opaque endianness */
__le32 Channel; /* Reserved MBZ */
__le32 RemainingBytes;
__le16 WriteChannelInfoOffset; /* Reserved MBZ */
__le16 WriteChannelInfoLength; /* Reserved MBZ */
__le32 Flags;
__u8 Buffer[1];
} __packed;
struct smb2_write_rsp {
struct smb2_hdr hdr;
__le16 StructureSize; /* Must be 17 */
__u8 DataOffset;
__u8 Reserved;
__le32 DataLength;
__le32 DataRemaining;
__u32 Reserved2;
__u8 Buffer[1];
} __packed;
struct smb2_echo_req {
struct smb2_hdr hdr;
__le16 StructureSize; /* Must be 4 */

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@ -98,6 +98,7 @@ extern int SMB2_get_srv_num(const unsigned int xid, struct cifs_tcon *tcon,
u64 persistent_fid, u64 volatile_fid,
__le64 *uniqueid);
extern int smb2_async_readv(struct cifs_readdata *rdata);
extern int smb2_async_writev(struct cifs_writedata *wdata);
extern int SMB2_echo(struct TCP_Server_Info *server);
#endif /* _SMB2PROTO_H */