Merge branch 'for-next' of git://git.samba.org/sfrench/cifs-2.6

Pull CIFS fixes from Steve French:
 "Misc small cifs fixes"

* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
  CIFS: Don't let read only caching for mandatory byte-range locked files
  CIFS: Fix write after setting a read lock for read oplock files
  Revert "CIFS: Fix write after setting a read lock for read oplock files"
  cifs: adjust sequence number downward after signing NT_CANCEL request
  cifs: move check for NULL socket into smb_send_rqst

6 files changed, 90 insertions, 70 deletions

diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index f653835d067b..de7f9168a118 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -228,7 +228,6 @@ cifs_alloc_inode(struct super_block *sb)
         cifs_set_oplock_level(cifs_inode, 0);
         cifs_inode->delete_pending = false;
         cifs_inode->invalid_mapping = false;
-        cifs_inode->leave_pages_clean = false;
         cifs_inode->vfs_inode.i_blkbits = 14;  /* 2**14 = CIFS_MAX_MSGSIZE */
         cifs_inode->server_eof = 0;
         cifs_inode->uniqueid = 0;
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index aea1eec64911..e6899cea1c35 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -386,6 +386,7 @@ struct smb_version_values {
         unsigned int    cap_unix;
         unsigned int    cap_nt_find;
         unsigned int    cap_large_files;
+        unsigned int    oplock_read;
 };
 
 #define HEADER_SIZE(server) (server->vals->header_size)
@@ -1030,7 +1031,6 @@ struct cifsInodeInfo {
         bool clientCanCacheAll;         /* read and writebehind oplock */
         bool delete_pending;            /* DELETE_ON_CLOSE is set */
         bool invalid_mapping;           /* pagecache is invalid */
-        bool leave_pages_clean; /* protected by i_mutex, not set pages dirty */
         unsigned long time;             /* jiffies of last update of inode */
         u64  server_eof;                /* current file size on server -- protected by i_lock */
         u64  uniqueid;                  /* server inode number */
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 0a6677ba212b..8ea6ca50a665 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -238,6 +238,23 @@ out:
         return rc;
 }
 
+static bool
+cifs_has_mand_locks(struct cifsInodeInfo *cinode)
+{
+        struct cifs_fid_locks *cur;
+        bool has_locks = false;
+
+        down_read(&cinode->lock_sem);
+        list_for_each_entry(cur, &cinode->llist, llist) {
+                if (!list_empty(&cur->locks)) {
+                        has_locks = true;
+                        break;
+                }
+        }
+        up_read(&cinode->lock_sem);
+        return has_locks;
+}
+
 struct cifsFileInfo *
 cifs_new_fileinfo(struct cifs_fid *fid, struct file *file,
                   struct tcon_link *tlink, __u32 oplock)
@@ -248,6 +265,7 @@ cifs_new_fileinfo(struct cifs_fid *fid, struct file *file,
         struct cifsFileInfo *cfile;
         struct cifs_fid_locks *fdlocks;
         struct cifs_tcon *tcon = tlink_tcon(tlink);
+        struct TCP_Server_Info *server = tcon->ses->server;
 
         cfile = kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
         if (cfile == NULL)
@@ -276,12 +294,22 @@ cifs_new_fileinfo(struct cifs_fid *fid, struct file *file,
         INIT_WORK(&cfile->oplock_break, cifs_oplock_break);
         mutex_init(&cfile->fh_mutex);
 
+        /*
+         * If the server returned a read oplock and we have mandatory brlocks,
+         * set oplock level to None.
+         */
+        if (oplock == server->vals->oplock_read &&
+                                                cifs_has_mand_locks(cinode)) {
+                cFYI(1, "Reset oplock val from read to None due to mand locks");
+                oplock = 0;
+        }
+
         spin_lock(&cifs_file_list_lock);
-        if (fid->pending_open->oplock != CIFS_OPLOCK_NO_CHANGE)
+        if (fid->pending_open->oplock != CIFS_OPLOCK_NO_CHANGE && oplock)
                 oplock = fid->pending_open->oplock;
         list_del(&fid->pending_open->olist);
 
-        tlink_tcon(tlink)->ses->server->ops->set_fid(cfile, fid, oplock);
+        server->ops->set_fid(cfile, fid, oplock);
 
         list_add(&cfile->tlist, &tcon->openFileList);
         /* if readable file instance put first in list*/
@@ -1422,6 +1450,7 @@ cifs_setlk(struct file *file, struct file_lock *flock, __u32 type,
         struct cifsFileInfo *cfile = (struct cifsFileInfo *)file->private_data;
         struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
         struct TCP_Server_Info *server = tcon->ses->server;
+        struct inode *inode = cfile->dentry->d_inode;
 
         if (posix_lck) {
                 int posix_lock_type;
@@ -1459,6 +1488,21 @@ cifs_setlk(struct file *file, struct file_lock *flock, __u32 type,
                 if (!rc)
                         goto out;
 
+                /*
+                 * Windows 7 server can delay breaking lease from read to None
+                 * if we set a byte-range lock on a file - break it explicitly
+                 * before sending the lock to the server to be sure the next
+                 * read won't conflict with non-overlapted locks due to
+                 * pagereading.
+                 */
+                if (!CIFS_I(inode)->clientCanCacheAll &&
+                                        CIFS_I(inode)->clientCanCacheRead) {
+                        cifs_invalidate_mapping(inode);
+                        cFYI(1, "Set no oplock for inode=%p due to mand locks",
+                             inode);
+                        CIFS_I(inode)->clientCanCacheRead = false;
+                }
+
                 rc = server->ops->mand_lock(xid, cfile, flock->fl_start, length,
                                             type, 1, 0, wait_flag);
                 if (rc) {
@@ -2103,15 +2147,7 @@ static int cifs_write_end(struct file *file, struct address_space *mapping,
         } else {
                 rc = copied;
                 pos += copied;
-                /*
-                 * When we use strict cache mode and cifs_strict_writev was run
-                 * with level II oplock (indicated by leave_pages_clean field of
-                 * CIFS_I(inode)), we can leave pages clean - cifs_strict_writev
-                 * sent the data to the server itself.
-                 */
-                if (!CIFS_I(inode)->leave_pages_clean ||
-                    !(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO))
-                        set_page_dirty(page);
+                set_page_dirty(page);
         }
 
         if (rc > 0) {
@@ -2462,8 +2498,8 @@ ssize_t cifs_user_writev(struct kiocb *iocb, const struct iovec *iov,
 }
 
 static ssize_t
-cifs_pagecache_writev(struct kiocb *iocb, const struct iovec *iov,
-                      unsigned long nr_segs, loff_t pos, bool cache_ex)
+cifs_writev(struct kiocb *iocb, const struct iovec *iov,
+            unsigned long nr_segs, loff_t pos)
 {
         struct file *file = iocb->ki_filp;
         struct cifsFileInfo *cfile = (struct cifsFileInfo *)file->private_data;
@@ -2485,12 +2521,8 @@ cifs_pagecache_writev(struct kiocb *iocb, const struct iovec *iov,
                                      server->vals->exclusive_lock_type, NULL,
                                      CIFS_WRITE_OP)) {
                 mutex_lock(&inode->i_mutex);
-                if (!cache_ex)
-                        cinode->leave_pages_clean = true;
                 rc = __generic_file_aio_write(iocb, iov, nr_segs,
-                                              &iocb->ki_pos);
-                if (!cache_ex)
-                        cinode->leave_pages_clean = false;
+                                               &iocb->ki_pos);
                 mutex_unlock(&inode->i_mutex);
         }
 
@@ -2517,60 +2549,32 @@ cifs_strict_writev(struct kiocb *iocb, const struct iovec *iov,
         struct cifsFileInfo *cfile = (struct cifsFileInfo *)
                                                 iocb->ki_filp->private_data;
         struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
-        ssize_t written, written2;
-        /*
-         * We need to store clientCanCacheAll here to prevent race
-         * conditions - this value can be changed during an execution
-         * of generic_file_aio_write. For CIFS it can be changed from
-         * true to false only, but for SMB2 it can be changed both from
-         * true to false and vice versa. So, we can end up with a data
-         * stored in the cache, not marked dirty and not sent to the
-         * server if this value changes its state from false to true
-         * after cifs_write_end.
-         */
-        bool cache_ex = cinode->clientCanCacheAll;
-        bool cache_read = cinode->clientCanCacheRead;
-        int rc;
-        loff_t saved_pos;
+        ssize_t written;
 
-        if (cache_ex) {
+        if (cinode->clientCanCacheAll) {
                 if (cap_unix(tcon->ses) &&
-                    ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0) &&
-                    (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(
-                                                tcon->fsUnixInfo.Capability)))
+                (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability))
+                    && ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
                         return generic_file_aio_write(iocb, iov, nr_segs, pos);
-                return cifs_pagecache_writev(iocb, iov, nr_segs, pos, cache_ex);
+                return cifs_writev(iocb, iov, nr_segs, pos);
         }
-
         /*
-         * For files without exclusive oplock in strict cache mode we need to
-         * write the data to the server exactly from the pos to pos+len-1 rather
-         * than flush all affected pages because it may cause a error with
-         * mandatory locks on these pages but not on the region from pos to
-         * ppos+len-1.
+         * For non-oplocked files in strict cache mode we need to write the data
+         * to the server exactly from the pos to pos+len-1 rather than flush all
+         * affected pages because it may cause a error with mandatory locks on
+         * these pages but not on the region from pos to ppos+len-1.
          */
         written = cifs_user_writev(iocb, iov, nr_segs, pos);
-        if (!cache_read || written <= 0)
-                return written;
-
-        saved_pos = iocb->ki_pos;
-        iocb->ki_pos = pos;
-        /* we have a read oplock - need to store a data in the page cache */
-        if (cap_unix(tcon->ses) &&
-            ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0) &&
-            (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(
-                                        tcon->fsUnixInfo.Capability)))
-                written2 = generic_file_aio_write(iocb, iov, nr_segs, pos);
-        else
-                written2 = cifs_pagecache_writev(iocb, iov, nr_segs, pos,
-                                                 cache_ex);
-        /* errors occured during writing - invalidate the page cache */
-        if (written2 < 0) {
-                rc = cifs_invalidate_mapping(inode);
-                if (rc)
-                        written = (ssize_t)rc;
-                else
-                        iocb->ki_pos = saved_pos;
+        if (written > 0 && cinode->clientCanCacheRead) {
+                /*
+                 * Windows 7 server can delay breaking level2 oplock if a write
+                 * request comes - break it on the client to prevent reading
+                 * an old data.
+                 */
+                cifs_invalidate_mapping(inode);
+                cFYI(1, "Set no oplock for inode=%p after a write operation",
+                     inode);
+                cinode->clientCanCacheRead = false;
         }
         return written;
 }
@@ -3577,6 +3581,13 @@ void cifs_oplock_break(struct work_struct *work)
         struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
         int rc = 0;
 
+        if (!cinode->clientCanCacheAll && cinode->clientCanCacheRead &&
+                                                cifs_has_mand_locks(cinode)) {
+                cFYI(1, "Reset oplock to None for inode=%p due to mand locks",
+                     inode);
+                cinode->clientCanCacheRead = false;
+        }
+
         if (inode && S_ISREG(inode->i_mode)) {
                 if (cinode->clientCanCacheRead)
                         break_lease(inode, O_RDONLY);
diff --git a/fs/cifs/smb1ops.c b/fs/cifs/smb1ops.c
index a5d234c8d5d9..47bc5a87f94e 100644
--- a/fs/cifs/smb1ops.c
+++ b/fs/cifs/smb1ops.c
@@ -53,6 +53,13 @@ send_nt_cancel(struct TCP_Server_Info *server, void *buf,
                 mutex_unlock(&server->srv_mutex);
                 return rc;
         }
+
+        /*
+         * The response to this call was already factored into the sequence
+         * number when the call went out, so we must adjust it back downward
+         * after signing here.
+         */
+        --server->sequence_number;
         rc = smb_send(server, in_buf, be32_to_cpu(in_buf->smb_buf_length));
         mutex_unlock(&server->srv_mutex);
 
@@ -952,4 +959,5 @@ struct smb_version_values smb1_values = {
         .cap_unix = CAP_UNIX,
         .cap_nt_find = CAP_NT_SMBS | CAP_NT_FIND,
         .cap_large_files = CAP_LARGE_FILES,
+        .oplock_read = OPLOCK_READ,
 };
diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index d79de7bc4435..c9c7aa7ed966 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -708,6 +708,7 @@ struct smb_version_values smb20_values = {
         .cap_unix = 0,
         .cap_nt_find = SMB2_NT_FIND,
         .cap_large_files = SMB2_LARGE_FILES,
+        .oplock_read = SMB2_OPLOCK_LEVEL_II,
 };
 
 struct smb_version_values smb21_values = {
@@ -725,6 +726,7 @@ struct smb_version_values smb21_values = {
         .cap_unix = 0,
         .cap_nt_find = SMB2_NT_FIND,
         .cap_large_files = SMB2_LARGE_FILES,
+        .oplock_read = SMB2_OPLOCK_LEVEL_II,
 };
 
 struct smb_version_values smb30_values = {
diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
index 76d974c952fe..1a528680ec5a 100644
--- a/fs/cifs/transport.c
+++ b/fs/cifs/transport.c
@@ -144,9 +144,6 @@ smb_send_kvec(struct TCP_Server_Info *server, struct kvec *iov, size_t n_vec,
 
         *sent = 0;
 
-        if (ssocket == NULL)
-                return -ENOTSOCK; /* BB eventually add reconnect code here */
-
         smb_msg.msg_name = (struct sockaddr *) &server->dstaddr;
         smb_msg.msg_namelen = sizeof(struct sockaddr);
         smb_msg.msg_control = NULL;
@@ -291,6 +288,9 @@ smb_send_rqst(struct TCP_Server_Info *server, struct smb_rqst *rqst)
         struct socket *ssocket = server->ssocket;
         int val = 1;
 
+        if (ssocket == NULL)
+                return -ENOTSOCK;
+
         cFYI(1, "Sending smb: smb_len=%u", smb_buf_length);
         dump_smb(iov[0].iov_base, iov[0].iov_len);