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From: Vivek Goyal <vgoyal@redhat.com>
To: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
	kvm@vger.kernel.org
Cc: vgoyal@redhat.com, miklos@szeredi.hu, stefanha@redhat.com,
	dgilbert@redhat.com, sweil@redhat.com, swhiteho@redhat.com
Subject: [PATCH 04/52] fuse: extract fuse_fill_super_common()
Date: Mon, 10 Dec 2018 12:12:30 -0500
Message-ID: <20181210171318.16998-5-vgoyal@redhat.com> (raw)
In-Reply-To: <20181210171318.16998-1-vgoyal@redhat.com>

From: Stefan Hajnoczi <stefanha@redhat.com>

fuse_fill_super() includes code to process the fd= option and link the
struct fuse_dev to the fd's struct file.  In virtio-fs there is no file
descriptor because /dev/fuse is not used.

This patch extracts fuse_fill_super_common() so that both classic fuse
and virtio-fs can share the code to initialize a mount.

parse_fuse_opt() is also extracted so that the fuse_fill_super_common()
caller has access to the mount options.  This allows classic fuse to
handle the fd= option outside fuse_fill_super_common().

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 fs/fuse/fuse_i.h |  32 +++++++++++++++++
 fs/fuse/inode.c  | 102 +++++++++++++++++++++++++++----------------------------
 2 files changed, 83 insertions(+), 51 deletions(-)

diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index e9f712e81c7d..9b5b8b194f77 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -56,6 +56,22 @@ extern struct mutex fuse_mutex;
 extern unsigned max_user_bgreq;
 extern unsigned max_user_congthresh;
 
+/** Mount options */
+struct fuse_mount_data {
+	int fd;
+	unsigned rootmode;
+	kuid_t user_id;
+	kgid_t group_id;
+	unsigned fd_present:1;
+	unsigned rootmode_present:1;
+	unsigned user_id_present:1;
+	unsigned group_id_present:1;
+	unsigned default_permissions:1;
+	unsigned allow_other:1;
+	unsigned max_read;
+	unsigned blksize;
+};
+
 /* One forget request */
 struct fuse_forget_link {
 	struct fuse_forget_one forget_one;
@@ -970,6 +986,22 @@ struct fuse_dev *fuse_dev_alloc(struct fuse_conn *fc);
 void fuse_dev_free(struct fuse_dev *fud);
 
 /**
+ * Parse a mount options string
+ */
+int parse_fuse_opt(char *opt, struct fuse_mount_data *d, int is_bdev,
+				struct user_namespace *user_ns);
+
+/**
+ * Fill in superblock and initialize fuse connection
+ * @sb: partially-initialized superblock to fill in
+ * @mount_data: mount parameters
+ * @fudptr: fuse_dev pointer to fill in, should contain NULL on entry
+ */
+int fuse_fill_super_common(struct super_block *sb,
+			   struct fuse_mount_data *mount_data,
+			   void **fudptr);
+
+/**
  * Add connection to control filesystem
  */
 int fuse_ctl_add_conn(struct fuse_conn *fc);
diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index d08cd8bf7705..f13133f0ebd1 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -59,21 +59,6 @@ MODULE_PARM_DESC(max_user_congthresh,
 /** Congestion starts at 75% of maximum */
 #define FUSE_DEFAULT_CONGESTION_THRESHOLD (FUSE_DEFAULT_MAX_BACKGROUND * 3 / 4)
 
-struct fuse_mount_data {
-	int fd;
-	unsigned rootmode;
-	kuid_t user_id;
-	kgid_t group_id;
-	unsigned fd_present:1;
-	unsigned rootmode_present:1;
-	unsigned user_id_present:1;
-	unsigned group_id_present:1;
-	unsigned default_permissions:1;
-	unsigned allow_other:1;
-	unsigned max_read;
-	unsigned blksize;
-};
-
 struct fuse_forget_link *fuse_alloc_forget(void)
 {
 	return kzalloc(sizeof(struct fuse_forget_link), GFP_KERNEL);
@@ -479,7 +464,7 @@ static int fuse_match_uint(substring_t *s, unsigned int *res)
 	return err;
 }
 
-static int parse_fuse_opt(char *opt, struct fuse_mount_data *d, int is_bdev,
+int parse_fuse_opt(char *opt, struct fuse_mount_data *d, int is_bdev,
 			  struct user_namespace *user_ns)
 {
 	char *p;
@@ -556,12 +541,13 @@ static int parse_fuse_opt(char *opt, struct fuse_mount_data *d, int is_bdev,
 		}
 	}
 
-	if (!d->fd_present || !d->rootmode_present ||
-	    !d->user_id_present || !d->group_id_present)
+	if (!d->rootmode_present || !d->user_id_present ||
+	    !d->group_id_present)
 		return 0;
 
 	return 1;
 }
+EXPORT_SYMBOL_GPL(parse_fuse_opt);
 
 static int fuse_show_options(struct seq_file *m, struct dentry *root)
 {
@@ -1072,13 +1058,13 @@ void fuse_dev_free(struct fuse_dev *fud)
 }
 EXPORT_SYMBOL_GPL(fuse_dev_free);
 
-static int fuse_fill_super(struct super_block *sb, void *data, int silent)
+int fuse_fill_super_common(struct super_block *sb,
+			   struct fuse_mount_data *mount_data,
+			   void **fudptr)
 {
 	struct fuse_dev *fud;
 	struct fuse_conn *fc;
 	struct inode *root;
-	struct fuse_mount_data d;
-	struct file *file;
 	struct dentry *root_dentry;
 	struct fuse_req *init_req;
 	int err;
@@ -1090,13 +1076,10 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent)
 
 	sb->s_flags &= ~(SB_NOSEC | SB_I_VERSION);
 
-	if (!parse_fuse_opt(data, &d, is_bdev, sb->s_user_ns))
-		goto err;
-
 	if (is_bdev) {
 #ifdef CONFIG_BLOCK
 		err = -EINVAL;
-		if (!sb_set_blocksize(sb, d.blksize))
+		if (!sb_set_blocksize(sb, mount_data->blksize))
 			goto err;
 #endif
 	} else {
@@ -1113,19 +1096,6 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent)
 	if (sb->s_user_ns != &init_user_ns)
 		sb->s_iflags |= SB_I_UNTRUSTED_MOUNTER;
 
-	file = fget(d.fd);
-	err = -EINVAL;
-	if (!file)
-		goto err;
-
-	/*
-	 * Require mount to happen from the same user namespace which
-	 * opened /dev/fuse to prevent potential attacks.
-	 */
-	if (file->f_op != &fuse_dev_operations ||
-	    file->f_cred->user_ns != sb->s_user_ns)
-		goto err_fput;
-
 	/*
 	 * If we are not in the initial user namespace posix
 	 * acls must be translated.
@@ -1136,7 +1106,7 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent)
 	fc = kmalloc(sizeof(*fc), GFP_KERNEL);
 	err = -ENOMEM;
 	if (!fc)
-		goto err_fput;
+		goto err;
 
 	fuse_conn_init(fc, sb->s_user_ns);
 	fc->release = fuse_free_conn;
@@ -1156,18 +1126,18 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent)
 		fc->dont_mask = 1;
 	sb->s_flags |= SB_POSIXACL;
 
-	fc->default_permissions = d.default_permissions;
-	fc->allow_other = d.allow_other;
-	fc->user_id = d.user_id;
-	fc->group_id = d.group_id;
-	fc->max_read = max_t(unsigned, 4096, d.max_read);
+	fc->default_permissions = mount_data->default_permissions;
+	fc->allow_other = mount_data->allow_other;
+	fc->user_id = mount_data->user_id;
+	fc->group_id = mount_data->group_id;
+	fc->max_read = max_t(unsigned, 4096, mount_data->max_read);
 	fc->max_pages = FUSE_DEFAULT_MAX_PAGES_PER_REQ;
 
 	/* Used by get_root_inode() */
 	sb->s_fs_info = fc;
 
 	err = -ENOMEM;
-	root = fuse_get_root_inode(sb, d.rootmode);
+	root = fuse_get_root_inode(sb, mount_data->rootmode);
 	sb->s_d_op = &fuse_root_dentry_operations;
 	root_dentry = d_make_root(root);
 	if (!root_dentry)
@@ -1188,7 +1158,7 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent)
 
 	mutex_lock(&fuse_mutex);
 	err = -EINVAL;
-	if (file->private_data)
+	if (*fudptr)
 		goto err_unlock;
 
 	err = fuse_ctl_add_conn(fc);
@@ -1197,13 +1167,12 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent)
 
 	list_add_tail(&fc->entry, &fuse_conn_list);
 	sb->s_root = root_dentry;
-	file->private_data = fud;
+	*fudptr = fud;
 	/*
 	 * mutex_unlock() provides the necessary memory barrier for
-	 * file->private_data to be visible on all CPUs after this
+	 * *fudptr to be visible on all CPUs after this
 	 */
 	mutex_unlock(&fuse_mutex);
-	fput(file);
 
 	fuse_send_init(fc, init_req);
 
@@ -1220,11 +1189,42 @@ static int fuse_fill_super(struct super_block *sb, void *data, int silent)
  err_put_conn:
 	fuse_conn_put(fc);
 	sb->s_fs_info = NULL;
- err_fput:
-	fput(file);
  err:
 	return err;
 }
+EXPORT_SYMBOL_GPL(fuse_fill_super_common);
+
+static int fuse_fill_super(struct super_block *sb, void *data, int silent)
+{
+	struct fuse_mount_data d;
+	struct file *file;
+	int is_bdev = sb->s_bdev != NULL;
+	int err;
+
+	err = -EINVAL;
+	if (!parse_fuse_opt(data, &d, is_bdev, sb->s_user_ns))
+		goto err;
+	if (!d.fd_present)
+		goto err;
+
+	file = fget(d.fd);
+	if (!file)
+		goto err;
+
+	/*
+	 * Require mount to happen from the same user namespace which
+	 * opened /dev/fuse to prevent potential attacks.
+	 */
+	if ((file->f_op != &fuse_dev_operations) ||
+	    (file->f_cred->user_ns != sb->s_user_ns))
+		goto err_fput;
+
+	err = fuse_fill_super_common(sb, &d, &file->private_data);
+err_fput:
+	fput(file);
+err:
+	return err;
+}
 
 static struct dentry *fuse_mount(struct file_system_type *fs_type,
 		       int flags, const char *dev_name,
-- 
2.13.6


  parent reply index

Thread overview: 98+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-12-10 17:12 [PATCH 00/52] [RFC] virtio-fs: shared file system for virtual machines Vivek Goyal
2018-12-10 17:12 ` [PATCH 01/52] fuse: add skeleton virtio_fs.ko module Vivek Goyal
2018-12-10 17:12 ` [PATCH 02/52] fuse: add probe/remove virtio driver Vivek Goyal
2018-12-10 17:12 ` [PATCH 03/52] fuse: rely on mutex_unlock() barrier instead of fput() Vivek Goyal
2018-12-10 17:12 ` Vivek Goyal [this message]
2018-12-10 17:12 ` [PATCH 05/52] virtio_fs: get mount working Vivek Goyal
2018-12-10 17:12 ` [PATCH 06/52] fuse: export fuse_end_request() Vivek Goyal
2018-12-10 17:12 ` [PATCH 07/52] fuse: export fuse_len_args() Vivek Goyal
2018-12-10 17:12 ` [PATCH 08/52] fuse: add fuse_iqueue_ops callbacks Vivek Goyal
2018-12-10 17:12 ` [PATCH 09/52] fuse: process requests queues Vivek Goyal
2018-12-10 17:12 ` [PATCH 10/52] fuse: export fuse_get_unique() Vivek Goyal
2018-12-10 17:12 ` [PATCH 11/52] fuse: implement FUSE_FORGET for virtio-fs Vivek Goyal
2018-12-10 17:12 ` [PATCH 12/52] virtio_fs: Set up dax_device Vivek Goyal
2018-12-10 17:12 ` [PATCH 13/52] dax: remove block device dependencies Vivek Goyal
2018-12-10 17:12 ` [PATCH 14/52] fuse: add fuse_conn->dax_dev field Vivek Goyal
2018-12-10 17:12 ` [PATCH 15/52] fuse: map virtio_fs DAX window BAR Vivek Goyal
2018-12-12 16:37   ` Christian Borntraeger
2018-12-13 11:55     ` Stefan Hajnoczi
2018-12-13 16:06   ` kbuild test robot
2018-12-13 19:55   ` Dan Williams
2018-12-13 20:09     ` Dr. David Alan Gilbert
2018-12-13 20:15       ` Dan Williams
2018-12-13 20:40         ` Vivek Goyal
2018-12-13 21:18           ` Vivek Goyal
2018-12-14 10:09             ` Dr. David Alan Gilbert
2018-12-10 17:12 ` [PATCH 16/52] virtio-fs: Add VIRTIO_PCI_CAP_SHARED_MEMORY_CFG and utility to find them Vivek Goyal
2018-12-12 16:36   ` [PATCH] virtio-fs: fix semicolon.cocci warnings kbuild test robot
2018-12-12 16:36   ` [PATCH 16/52] virtio-fs: Add VIRTIO_PCI_CAP_SHARED_MEMORY_CFG and utility to find them kbuild test robot
2018-12-10 17:12 ` [PATCH 17/52] virtio-fs: Retrieve shm capabilities for cache Vivek Goyal
2018-12-10 17:12 ` [PATCH 18/52] virtio-fs: Map cache using the values from the capabilities Vivek Goyal
2018-12-13  9:10   ` David Hildenbrand
2018-12-13  9:13     ` Dr. David Alan Gilbert
2018-12-13  9:34       ` David Hildenbrand
2018-12-13 10:00         ` Dr. David Alan Gilbert
2018-12-13 11:26           ` David Hildenbrand
2018-12-13 12:15             ` Dr. David Alan Gilbert
2018-12-13 12:24               ` David Hildenbrand
2018-12-13 12:38                 ` Cornelia Huck
2018-12-14 13:44                   ` Stefan Hajnoczi
2018-12-14 13:50                     ` Cornelia Huck
2018-12-14 14:06                       ` Dr. David Alan Gilbert
2018-12-17 11:25                       ` Stefan Hajnoczi
2018-12-17 10:53                     ` David Hildenbrand
2018-12-17 14:56                       ` Stefan Hajnoczi
2018-12-18 17:13                         ` Cornelia Huck
2018-12-18 17:25                           ` David Hildenbrand
2019-01-02 10:24                             ` Stefan Hajnoczi
2019-03-17  0:33   ` Liu Bo
2019-03-20 10:42     ` Dr. David Alan Gilbert
2019-03-17  0:35   ` [PATCH] virtio-fs: fix multiple tag support Liu Bo
2019-03-19 20:26     ` Vivek Goyal
2019-03-20  2:04       ` Liu Bo
2018-12-10 17:12 ` [PATCH 19/52] virito-fs: Make dax optional Vivek Goyal
2018-12-10 17:12 ` [PATCH 20/52] Limit number of pages returned by direct_access() Vivek Goyal
2018-12-10 17:12 ` [PATCH 21/52] fuse: Introduce fuse_dax_mapping Vivek Goyal
2018-12-10 17:12 ` [PATCH 22/52] Create a list of free memory ranges Vivek Goyal
2018-12-11 17:44   ` kbuild test robot
2018-12-15 19:22   ` kbuild test robot
2018-12-10 17:12 ` [PATCH 23/52] fuse: simplify fuse_fill_super_common() calling Vivek Goyal
2018-12-10 17:12 ` [PATCH 24/52] fuse: Introduce setupmapping/removemapping commands Vivek Goyal
2018-12-10 17:12 ` [PATCH 25/52] Introduce interval tree basic data structures Vivek Goyal
2018-12-10 17:12 ` [PATCH 26/52] fuse: Implement basic DAX read/write support commands Vivek Goyal
2018-12-10 17:12 ` [PATCH 27/52] fuse: Maintain a list of busy elements Vivek Goyal
2018-12-10 17:12 ` [PATCH 28/52] Do fallocate() to grow file before mapping for file growing writes Vivek Goyal
2018-12-11  6:13   ` kbuild test robot
2018-12-11  6:20   ` kbuild test robot
2018-12-10 17:12 ` [PATCH 29/52] fuse: add DAX mmap support Vivek Goyal
2018-12-10 17:12 ` [PATCH 30/52] fuse: delete dentry if timeout is zero Vivek Goyal
2018-12-10 17:12 ` [PATCH 31/52] dax: Pass dax_dev to dax_writeback_mapping_range() Vivek Goyal
2018-12-11  6:12   ` kbuild test robot
2018-12-11 17:38   ` kbuild test robot
2018-12-10 17:12 ` [PATCH 32/52] fuse: Define dax address space operations Vivek Goyal
2018-12-10 17:12 ` [PATCH 33/52] fuse, dax: Take ->i_mmap_sem lock during dax page fault Vivek Goyal
2018-12-10 17:13 ` [PATCH 34/52] fuse: Add logic to free up a memory range Vivek Goyal
2018-12-10 17:13 ` [PATCH 35/52] fuse: Add logic to do direct reclaim of memory Vivek Goyal
2018-12-10 17:13 ` [PATCH 36/52] fuse: Kick worker when free memory drops below 20% of total ranges Vivek Goyal
2018-12-10 17:13 ` [PATCH 37/52] fuse: multiplex cached/direct_io/dax file operations Vivek Goyal
2018-12-10 17:13 ` [PATCH 38/52] Dispatch FORGET requests later instead of dropping them Vivek Goyal
2018-12-10 17:13 ` [PATCH 39/52] Release file in process context Vivek Goyal
2018-12-10 17:13 ` [PATCH 40/52] fuse: Do not block on inode lock while freeing memory range Vivek Goyal
2018-12-10 17:13 ` [PATCH 41/52] fuse: Reschedule dax free work if too many EAGAIN attempts Vivek Goyal
2018-12-10 17:13 ` [PATCH 42/52] fuse: Wait for memory ranges to become free Vivek Goyal
2018-12-10 17:13 ` [PATCH 43/52] fuse: Take inode lock for dax inode truncation Vivek Goyal
2018-12-10 17:13 ` [PATCH 44/52] fuse: Clear setuid bit even in direct I/O path Vivek Goyal
2018-12-10 17:13 ` [PATCH 45/52] virtio: Free fuse devices on umount Vivek Goyal
2018-12-10 17:13 ` [PATCH 46/52] virtio-fs: Retrieve shm capabilities for version table Vivek Goyal
2018-12-10 17:13 ` [PATCH 47/52] virtio-fs: Map using the values from the capabilities Vivek Goyal
2018-12-10 17:13 ` [PATCH 48/52] virtio-fs: pass version table pointer to fuse Vivek Goyal
2018-12-10 17:13 ` [PATCH 49/52] fuse: don't crash if version table is NULL Vivek Goyal
2018-12-10 17:13 ` [PATCH 50/52] fuse: add shared version support (virtio-fs only) Vivek Goyal
2018-12-10 17:13 ` [PATCH 51/52] fuse: shared version cleanups Vivek Goyal
2018-12-10 17:13 ` [PATCH 52/52] fuse: fix fuse_permission() for the default_permissions case Vivek Goyal
2018-12-19 21:25   ` kbuild test robot
2018-12-11 12:54 ` [PATCH 00/52] [RFC] virtio-fs: shared file system for virtual machines Stefan Hajnoczi
2018-12-12 20:30 ` Konrad Rzeszutek Wilk
2018-12-12 21:22   ` Vivek Goyal
2019-02-12 15:56 ` Aneesh Kumar K.V
2019-02-12 18:57   ` Vivek Goyal

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