1 files changed, 125 insertions, 75 deletions

diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index 70b6f4c3a0c1..0a6677ba212b 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -505,16 +505,36 @@ out:
 	return rc;
 }
 
+static int cifs_push_posix_locks(struct cifsFileInfo *cfile);
+
 /*
  * Try to reacquire byte range locks that were released when session
- * to server was lost
+ * to server was lost.
  */
-static int cifs_relock_file(struct cifsFileInfo *cifsFile)
+static int
+cifs_relock_file(struct cifsFileInfo *cfile)
 {
+	struct cifs_sb_info *cifs_sb = CIFS_SB(cfile->dentry->d_sb);
+	struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode);
+	struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
 	int rc = 0;
 
-	/* BB list all locks open on this file and relock */
+	/* we are going to update can_cache_brlcks here - need a write access */
+	down_write(&cinode->lock_sem);
+	if (cinode->can_cache_brlcks) {
+		/* can cache locks - no need to push them */
+		up_write(&cinode->lock_sem);
+		return rc;
+	}
 
+	if (cap_unix(tcon->ses) &&
+	    (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
+	    ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
+		rc = cifs_push_posix_locks(cfile);
+	else
+		rc = tcon->ses->server->ops->push_mand_locks(cfile);
+
+	up_write(&cinode->lock_sem);
 	return rc;
 }
 
@@ -739,10 +759,15 @@ cifs_del_lock_waiters(struct cifsLockInfo *lock)
 	}
 }
 
+#define CIFS_LOCK_OP	0
+#define CIFS_READ_OP	1
+#define CIFS_WRITE_OP	2
+
+/* @rw_check : 0 - no op, 1 - read, 2 - write */
 static bool
 cifs_find_fid_lock_conflict(struct cifs_fid_locks *fdlocks, __u64 offset,
 			    __u64 length, __u8 type, struct cifsFileInfo *cfile,
-			    struct cifsLockInfo **conf_lock, bool rw_check)
+			    struct cifsLockInfo **conf_lock, int rw_check)
 {
 	struct cifsLockInfo *li;
 	struct cifsFileInfo *cur_cfile = fdlocks->cfile;
@@ -752,9 +777,13 @@ cifs_find_fid_lock_conflict(struct cifs_fid_locks *fdlocks, __u64 offset,
 		if (offset + length <= li->offset ||
 		    offset >= li->offset + li->length)
 			continue;
-		if (rw_check && server->ops->compare_fids(cfile, cur_cfile) &&
-		    current->tgid == li->pid)
-			continue;
+		if (rw_check != CIFS_LOCK_OP && current->tgid == li->pid &&
+		    server->ops->compare_fids(cfile, cur_cfile)) {
+			/* shared lock prevents write op through the same fid */
+			if (!(li->type & server->vals->shared_lock_type) ||
+			    rw_check != CIFS_WRITE_OP)
+				continue;
+		}
 		if ((type & server->vals->shared_lock_type) &&
 		    ((server->ops->compare_fids(cfile, cur_cfile) &&
 		     current->tgid == li->pid) || type == li->type))
@@ -769,7 +798,7 @@ cifs_find_fid_lock_conflict(struct cifs_fid_locks *fdlocks, __u64 offset,
 bool
 cifs_find_lock_conflict(struct cifsFileInfo *cfile, __u64 offset, __u64 length,
 			__u8 type, struct cifsLockInfo **conf_lock,
-			bool rw_check)
+			int rw_check)
 {
 	bool rc = false;
 	struct cifs_fid_locks *cur;
@@ -805,7 +834,7 @@ cifs_lock_test(struct cifsFileInfo *cfile, __u64 offset, __u64 length,
 	down_read(&cinode->lock_sem);
 
 	exist = cifs_find_lock_conflict(cfile, offset, length, type,
-					&conf_lock, false);
+					&conf_lock, CIFS_LOCK_OP);
 	if (exist) {
 		flock->fl_start = conf_lock->offset;
 		flock->fl_end = conf_lock->offset + conf_lock->length - 1;
@@ -852,7 +881,7 @@ try_again:
 	down_write(&cinode->lock_sem);
 
 	exist = cifs_find_lock_conflict(cfile, lock->offset, lock->length,
-					lock->type, &conf_lock, false);
+					lock->type, &conf_lock, CIFS_LOCK_OP);
 	if (!exist && cinode->can_cache_brlcks) {
 		list_add_tail(&lock->llist, &cfile->llist->locks);
 		up_write(&cinode->lock_sem);
@@ -948,7 +977,6 @@ cifs_push_mandatory_locks(struct cifsFileInfo *cfile)
 	int rc = 0, stored_rc;
 	struct cifsLockInfo *li, *tmp;
 	struct cifs_tcon *tcon;
-	struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode);
 	unsigned int num, max_num, max_buf;
 	LOCKING_ANDX_RANGE *buf, *cur;
 	int types[] = {LOCKING_ANDX_LARGE_FILES,
@@ -958,21 +986,12 @@ cifs_push_mandatory_locks(struct cifsFileInfo *cfile)
 	xid = get_xid();
 	tcon = tlink_tcon(cfile->tlink);
 
-	/* we are going to update can_cache_brlcks here - need a write access */
-	down_write(&cinode->lock_sem);
-	if (!cinode->can_cache_brlcks) {
-		up_write(&cinode->lock_sem);
-		free_xid(xid);
-		return rc;
-	}
-
 	/*
 	 * Accessing maxBuf is racy with cifs_reconnect - need to store value
 	 * and check it for zero before using.
 	 */
 	max_buf = tcon->ses->server->maxBuf;
 	if (!max_buf) {
-		up_write(&cinode->lock_sem);
 		free_xid(xid);
 		return -EINVAL;
 	}
@@ -981,7 +1000,6 @@ cifs_push_mandatory_locks(struct cifsFileInfo *cfile)
 						sizeof(LOCKING_ANDX_RANGE);
 	buf = kzalloc(max_num * sizeof(LOCKING_ANDX_RANGE), GFP_KERNEL);
 	if (!buf) {
-		up_write(&cinode->lock_sem);
 		free_xid(xid);
 		return -ENOMEM;
 	}
@@ -1018,9 +1036,6 @@ cifs_push_mandatory_locks(struct cifsFileInfo *cfile)
 		}
 	}
 
-	cinode->can_cache_brlcks = false;
-	up_write(&cinode->lock_sem);
-
 	kfree(buf);
 	free_xid(xid);
 	return rc;
@@ -1043,7 +1058,6 @@ struct lock_to_push {
 static int
 cifs_push_posix_locks(struct cifsFileInfo *cfile)
 {
-	struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode);
 	struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
 	struct file_lock *flock, **before;
 	unsigned int count = 0, i = 0;
@@ -1054,14 +1068,6 @@ cifs_push_posix_locks(struct cifsFileInfo *cfile)
 
 	xid = get_xid();
 
-	/* we are going to update can_cache_brlcks here - need a write access */
-	down_write(&cinode->lock_sem);
-	if (!cinode->can_cache_brlcks) {
-		up_write(&cinode->lock_sem);
-		free_xid(xid);
-		return rc;
-	}
-
 	lock_flocks();
 	cifs_for_each_lock(cfile->dentry->d_inode, before) {
 		if ((*before)->fl_flags & FL_POSIX)
@@ -1127,9 +1133,6 @@ cifs_push_posix_locks(struct cifsFileInfo *cfile)
 	}
 
 out:
-	cinode->can_cache_brlcks = false;
-	up_write(&cinode->lock_sem);
-
 	free_xid(xid);
 	return rc;
 err_out:
@@ -1144,14 +1147,27 @@ static int
 cifs_push_locks(struct cifsFileInfo *cfile)
 {
 	struct cifs_sb_info *cifs_sb = CIFS_SB(cfile->dentry->d_sb);
+	struct cifsInodeInfo *cinode = CIFS_I(cfile->dentry->d_inode);
 	struct cifs_tcon *tcon = tlink_tcon(cfile->tlink);
+	int rc = 0;
+
+	/* we are going to update can_cache_brlcks here - need a write access */
+	down_write(&cinode->lock_sem);
+	if (!cinode->can_cache_brlcks) {
+		up_write(&cinode->lock_sem);
+		return rc;
+	}
 
 	if (cap_unix(tcon->ses) &&
 	    (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(tcon->fsUnixInfo.Capability)) &&
 	    ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0))
-		return cifs_push_posix_locks(cfile);
+		rc = cifs_push_posix_locks(cfile);
+	else
+		rc = tcon->ses->server->ops->push_mand_locks(cfile);
 
-	return tcon->ses->server->ops->push_mand_locks(cfile);
+	cinode->can_cache_brlcks = false;
+	up_write(&cinode->lock_sem);
+	return rc;
 }
 
 static void
@@ -1436,16 +1452,18 @@ cifs_setlk(struct file *file, struct file_lock *flock, __u32 type,
 			return -ENOMEM;
 
 		rc = cifs_lock_add_if(cfile, lock, wait_flag);
-		if (rc < 0)
+		if (rc < 0) {
 			kfree(lock);
-		if (rc <= 0)
+			return rc;
+		}
+		if (!rc)
 			goto out;
 
 		rc = server->ops->mand_lock(xid, cfile, flock->fl_start, length,
 					    type, 1, 0, wait_flag);
 		if (rc) {
 			kfree(lock);
-			goto out;
+			return rc;
 		}
 
 		cifs_lock_add(cfile, lock);
@@ -2085,7 +2103,15 @@ static int cifs_write_end(struct file *file, struct address_space *mapping,
 	} else {
 		rc = copied;
 		pos += copied;
-		set_page_dirty(page);
+		/*
+		 * 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);
 	}
 
 	if (rc > 0) {
@@ -2436,8 +2462,8 @@ ssize_t cifs_user_writev(struct kiocb *iocb, const struct iovec *iov,
 }
 
 static ssize_t
-cifs_writev(struct kiocb *iocb, const struct iovec *iov,
-	    unsigned long nr_segs, loff_t pos)
+cifs_pagecache_writev(struct kiocb *iocb, const struct iovec *iov,
+		      unsigned long nr_segs, loff_t pos, bool cache_ex)
 {
 	struct file *file = iocb->ki_filp;
 	struct cifsFileInfo *cfile = (struct cifsFileInfo *)file->private_data;
@@ -2457,10 +2483,14 @@ cifs_writev(struct kiocb *iocb, const struct iovec *iov,
 	down_read(&cinode->lock_sem);
 	if (!cifs_find_lock_conflict(cfile, pos, iov_length(iov, nr_segs),
 				     server->vals->exclusive_lock_type, NULL,
-				     true)) {
+				     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);
+					      &iocb->ki_pos);
+		if (!cache_ex)
+			cinode->leave_pages_clean = false;
 		mutex_unlock(&inode->i_mutex);
 	}
 
@@ -2487,42 +2517,62 @@ 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);
-
-#ifdef CONFIG_CIFS_SMB2
+	ssize_t written, written2;
 	/*
-	 * If we have an oplock for read and want to write a data to the file
-	 * we need to store it in the page cache and then push it to the server
-	 * to be sure the next read will get a valid data.
+	 * 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.
 	 */
-	if (!cinode->clientCanCacheAll && cinode->clientCanCacheRead) {
-		ssize_t written;
-		int rc;
-
-		written = generic_file_aio_write(iocb, iov, nr_segs, pos);
-		rc = filemap_fdatawrite(inode->i_mapping);
-		if (rc)
-			return (ssize_t)rc;
+	bool cache_ex = cinode->clientCanCacheAll;
+	bool cache_read = cinode->clientCanCacheRead;
+	int rc;
+	loff_t saved_pos;
 
-		return written;
+	if (cache_ex) {
+		if (cap_unix(tcon->ses) &&
+		    ((cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NOPOSIXBRL) == 0) &&
+		    (CIFS_UNIX_FCNTL_CAP & le64_to_cpu(
+						tcon->fsUnixInfo.Capability)))
+			return generic_file_aio_write(iocb, iov, nr_segs, pos);
+		return cifs_pagecache_writev(iocb, iov, nr_segs, pos, cache_ex);
 	}
-#endif
 
 	/*
-	 * 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.
+	 * 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.
 	 */
+	written = cifs_user_writev(iocb, iov, nr_segs, pos);
+	if (!cache_read || written <= 0)
+		return written;
 
-	if (!cinode->clientCanCacheAll)
-		return cifs_user_writev(iocb, iov, nr_segs, pos);
-
+	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_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_writev(iocb, iov, nr_segs, pos);
+	    ((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;
+	}
+	return written;
 }
 
 static struct cifs_readdata *
@@ -2892,7 +2942,7 @@ cifs_strict_readv(struct kiocb *iocb, const struct iovec *iov,
 	down_read(&cinode->lock_sem);
 	if (!cifs_find_lock_conflict(cfile, pos, iov_length(iov, nr_segs),
 				     tcon->ses->server->vals->shared_lock_type,
-				     NULL, true))
+				     NULL, CIFS_READ_OP))
 		rc = generic_file_aio_read(iocb, iov, nr_segs, pos);
 	up_read(&cinode->lock_sem);
 	return rc;
@@ -3536,7 +3586,7 @@ void cifs_oplock_break(struct work_struct *work)
 		if (cinode->clientCanCacheRead == 0) {
 			rc = filemap_fdatawait(inode->i_mapping);
 			mapping_set_error(inode->i_mapping, rc);
-			invalidate_remote_inode(inode);
+			cifs_invalidate_mapping(inode);
 		}
 		cFYI(1, "Oplock flush inode %p rc %d", inode, rc);
 	}