Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ericvh/v9fs:
  [net/9p]: Introduce basic flow-control for VirtIO transport.
  9p: use the updated offset given by generic_write_checks
  [net/9p] Don't re-pin pages on retrying virtqueue_add_buf().
  [net/9p] Set the condition just before waking up.
  [net/9p] unconditional wake_up to proc waiting for space on VirtIO ring
  fs/9p: Add v9fs_dentry2v9ses
  fs/9p: Attach writeback_fid on first open with WR flag
  fs/9p: Open writeback fid in O_SYNC mode
  fs/9p: Use truncate_setsize instead of vmtruncate
  net/9p: Fix compile warning
  net/9p: Convert the in the 9p rpc call path to GFP_NOFS
  fs/9p: Fix race in initializing writeback fid

7 files changed, 65 insertions, 30 deletions

diff --git a/fs/9p/acl.c b/fs/9p/acl.c
index 51545529637..33aa116732c 100644
--- a/fs/9p/acl.c
+++ b/fs/9p/acl.c
@@ -262,7 +262,7 @@ static int v9fs_xattr_get_acl(struct dentry *dentry, const char *name,
 	if (strcmp(name, "") != 0)
 		return -EINVAL;
 
-	v9ses = v9fs_inode2v9ses(dentry->d_inode);
+	v9ses = v9fs_dentry2v9ses(dentry);
 	/*
 	 * We allow set/get/list of acl when access=client is not specified
 	 */
@@ -312,7 +312,7 @@ static int v9fs_xattr_set_acl(struct dentry *dentry, const char *name,
 	if (strcmp(name, "") != 0)
 		return -EINVAL;
 
-	v9ses = v9fs_inode2v9ses(dentry->d_inode);
+	v9ses = v9fs_dentry2v9ses(dentry);
 	/*
 	 * set the attribute on the remote. Without even looking at the
 	 * xattr value. We leave it to the server to validate
diff --git a/fs/9p/fid.c b/fs/9p/fid.c
index cd63e002d82..0ee594569dc 100644
--- a/fs/9p/fid.c
+++ b/fs/9p/fid.c
@@ -134,7 +134,7 @@ static struct p9_fid *v9fs_fid_lookup_with_uid(struct dentry *dentry,
 	struct v9fs_session_info *v9ses;
 	struct p9_fid *fid, *old_fid = NULL;
 
-	v9ses = v9fs_inode2v9ses(dentry->d_inode);
+	v9ses = v9fs_dentry2v9ses(dentry);
 	access = v9ses->flags & V9FS_ACCESS_MASK;
 	fid = v9fs_fid_find(dentry, uid, any);
 	if (fid)
@@ -237,7 +237,7 @@ struct p9_fid *v9fs_fid_lookup(struct dentry *dentry)
 	int  any, access;
 	struct v9fs_session_info *v9ses;
 
-	v9ses = v9fs_inode2v9ses(dentry->d_inode);
+	v9ses = v9fs_dentry2v9ses(dentry);
 	access = v9ses->flags & V9FS_ACCESS_MASK;
 	switch (access) {
 	case V9FS_ACCESS_SINGLE:
@@ -286,9 +286,11 @@ static struct p9_fid *v9fs_fid_clone_with_uid(struct dentry *dentry, uid_t uid)
 
 struct p9_fid *v9fs_writeback_fid(struct dentry *dentry)
 {
-	int err;
+	int err, flags;
 	struct p9_fid *fid;
+	struct v9fs_session_info *v9ses;
 
+	v9ses = v9fs_dentry2v9ses(dentry);
 	fid = v9fs_fid_clone_with_uid(dentry, 0);
 	if (IS_ERR(fid))
 		goto error_out;
@@ -297,8 +299,17 @@ struct p9_fid *v9fs_writeback_fid(struct dentry *dentry)
 	 * dirty pages. We always request for the open fid in read-write
 	 * mode so that a partial page write which result in page
 	 * read can work.
+	 *
+	 * we don't have a tsyncfs operation for older version
+	 * of protocol. So make sure the write back fid is
+	 * opened in O_SYNC mode.
 	 */
-	err = p9_client_open(fid, O_RDWR);
+	if (!v9fs_proto_dotl(v9ses))
+		flags = O_RDWR | O_SYNC;
+	else
+		flags = O_RDWR;
+
+	err = p9_client_open(fid, flags);
 	if (err < 0) {
 		p9_client_clunk(fid);
 		fid = ERR_PTR(err);
diff --git a/fs/9p/v9fs.h b/fs/9p/v9fs.h
index bd8496db135..9665c2b840e 100644
--- a/fs/9p/v9fs.h
+++ b/fs/9p/v9fs.h
@@ -130,6 +130,7 @@ struct v9fs_inode {
 #endif
 	unsigned int cache_validity;
 	struct p9_fid *writeback_fid;
+	struct mutex v_mutex;
 	struct inode vfs_inode;
 };
 
@@ -173,6 +174,11 @@ static inline struct v9fs_session_info *v9fs_inode2v9ses(struct inode *inode)
 	return (inode->i_sb->s_fs_info);
 }
 
+static inline struct v9fs_session_info *v9fs_dentry2v9ses(struct dentry *dentry)
+{
+	return dentry->d_sb->s_fs_info;
+}
+
 static inline int v9fs_proto_dotu(struct v9fs_session_info *v9ses)
 {
 	return v9ses->flags & V9FS_PROTO_2000U;
diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c
index 78bcb97c342..ffed55817f0 100644
--- a/fs/9p/vfs_file.c
+++ b/fs/9p/vfs_file.c
@@ -90,7 +90,9 @@ int v9fs_file_open(struct inode *inode, struct file *file)
 	}
 
 	file->private_data = fid;
-	if (v9ses->cache && !v9inode->writeback_fid) {
+	mutex_lock(&v9inode->v_mutex);
+	if (v9ses->cache && !v9inode->writeback_fid &&
+	    ((file->f_flags & O_ACCMODE) != O_RDONLY)) {
 		/*
 		 * clone a fid and add it to writeback_fid
 		 * we do it during open time instead of
@@ -101,10 +103,12 @@ int v9fs_file_open(struct inode *inode, struct file *file)
 		fid = v9fs_writeback_fid(file->f_path.dentry);
 		if (IS_ERR(fid)) {
 			err = PTR_ERR(fid);
+			mutex_unlock(&v9inode->v_mutex);
 			goto out_error;
 		}
 		v9inode->writeback_fid = (void *) fid;
 	}
+	mutex_unlock(&v9inode->v_mutex);
 #ifdef CONFIG_9P_FSCACHE
 	if (v9ses->cache)
 		v9fs_cache_inode_set_cookie(inode, file);
@@ -504,9 +508,12 @@ v9fs_file_write(struct file *filp, const char __user * data,
 	if (!count)
 		goto out;
 
-	return v9fs_file_write_internal(filp->f_path.dentry->d_inode,
+	retval = v9fs_file_write_internal(filp->f_path.dentry->d_inode,
 					filp->private_data,
-					data, count, offset, 1);
+					data, count, &origin, 1);
+	/* update offset on successful write */
+	if (retval > 0)
+		*offset = origin;
 out:
 	return retval;
 }
diff --git a/fs/9p/vfs_inode.c b/fs/9p/vfs_inode.c
index 8a2c232f708..7f6c6770319 100644
--- a/fs/9p/vfs_inode.c
+++ b/fs/9p/vfs_inode.c
@@ -221,6 +221,7 @@ struct inode *v9fs_alloc_inode(struct super_block *sb)
 #endif
 	v9inode->writeback_fid = NULL;
 	v9inode->cache_validity = 0;
+	mutex_init(&v9inode->v_mutex);
 	return &v9inode->vfs_inode;
 }
 
@@ -650,7 +651,9 @@ v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode,
 	/* if we are opening a file, assign the open fid to the file */
 	if (nd && nd->flags & LOOKUP_OPEN) {
 		v9inode = V9FS_I(dentry->d_inode);
-		if (v9ses->cache && !v9inode->writeback_fid) {
+		mutex_lock(&v9inode->v_mutex);
+		if (v9ses->cache && !v9inode->writeback_fid &&
+		    ((flags & O_ACCMODE) != O_RDONLY)) {
 			/*
 			 * clone a fid and add it to writeback_fid
 			 * we do it during open time instead of
@@ -661,10 +664,12 @@ v9fs_vfs_create(struct inode *dir, struct dentry *dentry, int mode,
 			inode_fid = v9fs_writeback_fid(dentry);
 			if (IS_ERR(inode_fid)) {
 				err = PTR_ERR(inode_fid);
+				mutex_unlock(&v9inode->v_mutex);
 				goto error;
 			}
 			v9inode->writeback_fid = (void *) inode_fid;
 		}
+		mutex_unlock(&v9inode->v_mutex);
 		filp = lookup_instantiate_filp(nd, dentry, generic_file_open);
 		if (IS_ERR(filp)) {
 			err = PTR_ERR(filp);
@@ -931,7 +936,7 @@ v9fs_vfs_getattr(struct vfsmount *mnt, struct dentry *dentry,
 
 	P9_DPRINTK(P9_DEBUG_VFS, "dentry: %p\n", dentry);
 	err = -EPERM;
-	v9ses = v9fs_inode2v9ses(dentry->d_inode);
+	v9ses = v9fs_dentry2v9ses(dentry);
 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
 		generic_fillattr(dentry->d_inode, stat);
 		return 0;
@@ -967,8 +972,12 @@ static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
 	struct p9_wstat wstat;
 
 	P9_DPRINTK(P9_DEBUG_VFS, "\n");
+	retval = inode_change_ok(dentry->d_inode, iattr);
+	if (retval)
+		return retval;
+
 	retval = -EPERM;
-	v9ses = v9fs_inode2v9ses(dentry->d_inode);
+	v9ses = v9fs_dentry2v9ses(dentry);
 	fid = v9fs_fid_lookup(dentry);
 	if(IS_ERR(fid))
 		return PTR_ERR(fid);
@@ -993,12 +1002,7 @@ static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
 		if (iattr->ia_valid & ATTR_GID)
 			wstat.n_gid = iattr->ia_gid;
 	}
-	if ((iattr->ia_valid & ATTR_SIZE) &&
-	    iattr->ia_size != i_size_read(dentry->d_inode)) {
-		retval = vmtruncate(dentry->d_inode, iattr->ia_size);
-		if (retval)
-			return retval;
-	}
+
 	/* Write all dirty data */
 	if (S_ISREG(dentry->d_inode->i_mode))
 		filemap_write_and_wait(dentry->d_inode->i_mapping);
@@ -1006,6 +1010,11 @@ static int v9fs_vfs_setattr(struct dentry *dentry, struct iattr *iattr)
 	retval = p9_client_wstat(fid, &wstat);
 	if (retval < 0)
 		return retval;
+
+	if ((iattr->ia_valid & ATTR_SIZE) &&
+	    iattr->ia_size != i_size_read(dentry->d_inode))
+		truncate_setsize(dentry->d_inode, iattr->ia_size);
+
 	v9fs_invalidate_inode_attr(dentry->d_inode);
 
 	setattr_copy(dentry->d_inode, iattr);
@@ -1130,7 +1139,7 @@ static int v9fs_readlink(struct dentry *dentry, char *buffer, int buflen)
 
 	P9_DPRINTK(P9_DEBUG_VFS, " %s\n", dentry->d_name.name);
 	retval = -EPERM;
-	v9ses = v9fs_inode2v9ses(dentry->d_inode);
+	v9ses = v9fs_dentry2v9ses(dentry);
 	fid = v9fs_fid_lookup(dentry);
 	if (IS_ERR(fid))
 		return PTR_ERR(fid);
diff --git a/fs/9p/vfs_inode_dotl.c b/fs/9p/vfs_inode_dotl.c
index 67c138e94fe..ffbb113d5f3 100644
--- a/fs/9p/vfs_inode_dotl.c
+++ b/fs/9p/vfs_inode_dotl.c
@@ -245,7 +245,9 @@ v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, int omode,
 	v9fs_set_create_acl(dentry, dacl, pacl);
 
 	v9inode = V9FS_I(inode);
-	if (v9ses->cache && !v9inode->writeback_fid) {
+	mutex_lock(&v9inode->v_mutex);
+	if (v9ses->cache && !v9inode->writeback_fid &&
+	    ((flags & O_ACCMODE) != O_RDONLY)) {
 		/*
 		 * clone a fid and add it to writeback_fid
 		 * we do it during open time instead of
@@ -256,10 +258,12 @@ v9fs_vfs_create_dotl(struct inode *dir, struct dentry *dentry, int omode,
 		inode_fid = v9fs_writeback_fid(dentry);
 		if (IS_ERR(inode_fid)) {
 			err = PTR_ERR(inode_fid);
+			mutex_unlock(&v9inode->v_mutex);
 			goto error;
 		}
 		v9inode->writeback_fid = (void *) inode_fid;
 	}
+	mutex_unlock(&v9inode->v_mutex);
 	/* Since we are opening a file, assign the open fid to the file */
 	filp = lookup_instantiate_filp(nd, dentry, generic_file_open);
 	if (IS_ERR(filp)) {
@@ -391,7 +395,7 @@ v9fs_vfs_getattr_dotl(struct vfsmount *mnt, struct dentry *dentry,
 
 	P9_DPRINTK(P9_DEBUG_VFS, "dentry: %p\n", dentry);
 	err = -EPERM;
-	v9ses = v9fs_inode2v9ses(dentry->d_inode);
+	v9ses = v9fs_dentry2v9ses(dentry);
 	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {
 		generic_fillattr(dentry->d_inode, stat);
 		return 0;
@@ -448,17 +452,11 @@ int v9fs_vfs_setattr_dotl(struct dentry *dentry, struct iattr *iattr)
 	p9attr.mtime_nsec = iattr->ia_mtime.tv_nsec;
 
 	retval = -EPERM;
-	v9ses = v9fs_inode2v9ses(dentry->d_inode);
+	v9ses = v9fs_dentry2v9ses(dentry);
 	fid = v9fs_fid_lookup(dentry);
 	if (IS_ERR(fid))
 		return PTR_ERR(fid);
 
-	if ((iattr->ia_valid & ATTR_SIZE) &&
-	    iattr->ia_size != i_size_read(dentry->d_inode)) {
-		retval = vmtruncate(dentry->d_inode, iattr->ia_size);
-		if (retval)
-			return retval;
-	}
 	/* Write all dirty data */
 	if (S_ISREG(dentry->d_inode->i_mode))
 		filemap_write_and_wait(dentry->d_inode->i_mapping);
@@ -466,8 +464,12 @@ int v9fs_vfs_setattr_dotl(struct dentry *dentry, struct iattr *iattr)
 	retval = p9_client_setattr(fid, &p9attr);
 	if (retval < 0)
 		return retval;
-	v9fs_invalidate_inode_attr(dentry->d_inode);
 
+	if ((iattr->ia_valid & ATTR_SIZE) &&
+	    iattr->ia_size != i_size_read(dentry->d_inode))
+		truncate_setsize(dentry->d_inode, iattr->ia_size);
+
+	v9fs_invalidate_inode_attr(dentry->d_inode);
 	setattr_copy(dentry->d_inode, iattr);
 	mark_inode_dirty(dentry->d_inode);
 	if (iattr->ia_valid & ATTR_MODE) {
diff --git a/fs/9p/vfs_super.c b/fs/9p/vfs_super.c
index 09fd08d1606..f3eed3383e4 100644
--- a/fs/9p/vfs_super.c
+++ b/fs/9p/vfs_super.c
@@ -262,7 +262,7 @@ static int v9fs_statfs(struct dentry *dentry, struct kstatfs *buf)
 		goto done;
 	}
 
-	v9ses = v9fs_inode2v9ses(dentry->d_inode);
+	v9ses = v9fs_dentry2v9ses(dentry);
 	if (v9fs_proto_dotl(v9ses)) {
 		res = p9_client_statfs(fid, &rs);
 		if (res == 0) {