Merge branch 'work.mount2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull misc mount API conversions from Al Viro:
 "Conversions to new API for shmem and friends and for mount_mtd()-using
  filesystems.

  As for the rest of the mount API conversions in -next, some of them
  belong in the individual trees (e.g. binderfs one should definitely go
  through android folks, after getting redone on top of their changes).
  I'm going to drop those and send the rest (trivial ones + stuff ACKed
  by maintainers) in a separate series - by that point they are
  independent from each other.

  Some stuff has already migrated into individual trees (NFS conversion,
  for example, or FUSE stuff, etc.); those presumably will go through
  the regular merges from corresponding trees."

* 'work.mount2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  vfs: Make fs_parse() handle fs_param_is_fd-type params better
  vfs: Convert ramfs, shmem, tmpfs, devtmpfs, rootfs to use the new mount API
  shmem_parse_one(): switch to use of fs_parse()
  shmem_parse_options(): take handling a single option into a helper
  shmem_parse_options(): don't bother with mpol in separate variable
  shmem_parse_options(): use a separate structure to keep the results
  make shmem_fill_super() static
  make ramfs_fill_super() static
  devtmpfs: don't mix {ramfs,shmem}_fill_super() with mount_single()
  vfs: Convert squashfs to use the new mount API
  mtd: Kill mount_mtd()
  vfs: Convert jffs2 to use the new mount API
  vfs: Convert cramfs to use the new mount API
  vfs: Convert romfs to use the new mount API
  vfs: Add a single-or-reconfig keying to vfs_get_super()

1 files changed, 55 insertions, 45 deletions

diff --git a/fs/squashfs/super.c b/fs/squashfs/super.c
index a9e9837617a9..0cc4ceec0562 100644
--- a/fs/squashfs/super.c
+++ b/fs/squashfs/super.c
@@ -17,6 +17,7 @@
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
 #include <linux/fs.h>
+#include <linux/fs_context.h>
 #include <linux/vfs.h>
 #include <linux/slab.h>
 #include <linux/mutex.h>
@@ -36,26 +37,27 @@
 static struct file_system_type squashfs_fs_type;
 static const struct super_operations squashfs_super_ops;
 
-static const struct squashfs_decompressor *supported_squashfs_filesystem(short
-	major, short minor, short id)
+static const struct squashfs_decompressor *supported_squashfs_filesystem(
+	struct fs_context *fc,
+	short major, short minor, short id)
 {
 	const struct squashfs_decompressor *decompressor;
 
 	if (major < SQUASHFS_MAJOR) {
-		ERROR("Major/Minor mismatch, older Squashfs %d.%d "
-			"filesystems are unsupported\n", major, minor);
+		errorf(fc, "Major/Minor mismatch, older Squashfs %d.%d "
+		       "filesystems are unsupported", major, minor);
 		return NULL;
 	} else if (major > SQUASHFS_MAJOR || minor > SQUASHFS_MINOR) {
-		ERROR("Major/Minor mismatch, trying to mount newer "
-			"%d.%d filesystem\n", major, minor);
-		ERROR("Please update your kernel\n");
+		errorf(fc, "Major/Minor mismatch, trying to mount newer "
+		       "%d.%d filesystem", major, minor);
+		errorf(fc, "Please update your kernel");
 		return NULL;
 	}
 
 	decompressor = squashfs_lookup_decompressor(id);
 	if (!decompressor->supported) {
-		ERROR("Filesystem uses \"%s\" compression. This is not "
-			"supported\n", decompressor->name);
+		errorf(fc, "Filesystem uses \"%s\" compression. This is not supported",
+		       decompressor->name);
 		return NULL;
 	}
 
@@ -63,7 +65,7 @@ static const struct squashfs_decompressor *supported_squashfs_filesystem(short
 }
 
 
-static int squashfs_fill_super(struct super_block *sb, void *data, int silent)
+static int squashfs_fill_super(struct super_block *sb, struct fs_context *fc)
 {
 	struct squashfs_sb_info *msblk;
 	struct squashfs_super_block *sblk = NULL;
@@ -98,7 +100,7 @@ static int squashfs_fill_super(struct super_block *sb, void *data, int silent)
 	sblk = squashfs_read_table(sb, SQUASHFS_START, sizeof(*sblk));
 
 	if (IS_ERR(sblk)) {
-		ERROR("unable to read squashfs_super_block\n");
+		errorf(fc, "unable to read squashfs_super_block");
 		err = PTR_ERR(sblk);
 		sblk = NULL;
 		goto failed_mount;
@@ -109,14 +111,15 @@ static int squashfs_fill_super(struct super_block *sb, void *data, int silent)
 	/* Check it is a SQUASHFS superblock */
 	sb->s_magic = le32_to_cpu(sblk->s_magic);
 	if (sb->s_magic != SQUASHFS_MAGIC) {
-		if (!silent)
-			ERROR("Can't find a SQUASHFS superblock on %pg\n",
-						sb->s_bdev);
+		if (!(fc->sb_flags & SB_SILENT))
+			errorf(fc, "Can't find a SQUASHFS superblock on %pg",
+			       sb->s_bdev);
 		goto failed_mount;
 	}
 
 	/* Check the MAJOR & MINOR versions and lookup compression type */
 	msblk->decompressor = supported_squashfs_filesystem(
+			fc,
 			le16_to_cpu(sblk->s_major),
 			le16_to_cpu(sblk->s_minor),
 			le16_to_cpu(sblk->compression));
@@ -133,15 +136,15 @@ static int squashfs_fill_super(struct super_block *sb, void *data, int silent)
 	/* Check block size for sanity */
 	msblk->block_size = le32_to_cpu(sblk->block_size);
 	if (msblk->block_size > SQUASHFS_FILE_MAX_SIZE)
-		goto failed_mount;
+		goto insanity;
 
 	/*
 	 * Check the system page size is not larger than the filesystem
 	 * block size (by default 128K).  This is currently not supported.
 	 */
 	if (PAGE_SIZE > msblk->block_size) {
-		ERROR("Page size > filesystem block size (%d).  This is "
-			"currently not supported!\n", msblk->block_size);
+		errorf(fc, "Page size > filesystem block size (%d).  This is "
+		       "currently not supported!", msblk->block_size);
 		goto failed_mount;
 	}
 
@@ -152,12 +155,12 @@ static int squashfs_fill_super(struct super_block *sb, void *data, int silent)
 
 	/* Check that block_size and block_log match */
 	if (msblk->block_size != (1 << msblk->block_log))
-		goto failed_mount;
+		goto insanity;
 
 	/* Check the root inode for sanity */
 	root_inode = le64_to_cpu(sblk->root_inode);
 	if (SQUASHFS_INODE_OFFSET(root_inode) > SQUASHFS_METADATA_SIZE)
-		goto failed_mount;
+		goto insanity;
 
 	msblk->inode_table = le64_to_cpu(sblk->inode_table_start);
 	msblk->directory_table = le64_to_cpu(sblk->directory_table_start);
@@ -199,7 +202,7 @@ static int squashfs_fill_super(struct super_block *sb, void *data, int silent)
 	msblk->read_page = squashfs_cache_init("data",
 		squashfs_max_decompressors(), msblk->block_size);
 	if (msblk->read_page == NULL) {
-		ERROR("Failed to allocate read_page block\n");
+		errorf(fc, "Failed to allocate read_page block");
 		goto failed_mount;
 	}
 
@@ -207,7 +210,7 @@ static int squashfs_fill_super(struct super_block *sb, void *data, int silent)
 	if (IS_ERR(msblk->stream)) {
 		err = PTR_ERR(msblk->stream);
 		msblk->stream = NULL;
-		goto failed_mount;
+		goto insanity;
 	}
 
 	/* Handle xattrs */
@@ -222,7 +225,7 @@ static int squashfs_fill_super(struct super_block *sb, void *data, int silent)
 	msblk->xattr_id_table = squashfs_read_xattr_id_table(sb,
 		xattr_id_table_start, &msblk->xattr_table, &msblk->xattr_ids);
 	if (IS_ERR(msblk->xattr_id_table)) {
-		ERROR("unable to read xattr id index table\n");
+		errorf(fc, "unable to read xattr id index table");
 		err = PTR_ERR(msblk->xattr_id_table);
 		msblk->xattr_id_table = NULL;
 		if (err != -ENOTSUPP)
@@ -236,7 +239,7 @@ allocate_id_index_table:
 		le64_to_cpu(sblk->id_table_start), next_table,
 		le16_to_cpu(sblk->no_ids));
 	if (IS_ERR(msblk->id_table)) {
-		ERROR("unable to read id index table\n");
+		errorf(fc, "unable to read id index table");
 		err = PTR_ERR(msblk->id_table);
 		msblk->id_table = NULL;
 		goto failed_mount;
@@ -252,7 +255,7 @@ allocate_id_index_table:
 	msblk->inode_lookup_table = squashfs_read_inode_lookup_table(sb,
 		lookup_table_start, next_table, msblk->inodes);
 	if (IS_ERR(msblk->inode_lookup_table)) {
-		ERROR("unable to read inode lookup table\n");
+		errorf(fc, "unable to read inode lookup table");
 		err = PTR_ERR(msblk->inode_lookup_table);
 		msblk->inode_lookup_table = NULL;
 		goto failed_mount;
@@ -277,7 +280,7 @@ handle_fragments:
 	msblk->fragment_index = squashfs_read_fragment_index_table(sb,
 		le64_to_cpu(sblk->fragment_table_start), next_table, fragments);
 	if (IS_ERR(msblk->fragment_index)) {
-		ERROR("unable to read fragment index table\n");
+		errorf(fc, "unable to read fragment index table");
 		err = PTR_ERR(msblk->fragment_index);
 		msblk->fragment_index = NULL;
 		goto failed_mount;
@@ -288,13 +291,13 @@ check_directory_table:
 	/* Sanity check directory_table */
 	if (msblk->directory_table > next_table) {
 		err = -EINVAL;
-		goto failed_mount;
+		goto insanity;
 	}
 
 	/* Sanity check inode_table */
 	if (msblk->inode_table >= msblk->directory_table) {
 		err = -EINVAL;
-		goto failed_mount;
+		goto insanity;
 	}
 
 	/* allocate root */
@@ -323,6 +326,8 @@ check_directory_table:
 	kfree(sblk);
 	return 0;
 
+insanity:
+	errorf(fc, "squashfs image failed sanity check");
 failed_mount:
 	squashfs_cache_delete(msblk->block_cache);
 	squashfs_cache_delete(msblk->fragment_cache);
@@ -338,6 +343,28 @@ failed_mount:
 	return err;
 }
 
+static int squashfs_get_tree(struct fs_context *fc)
+{
+	return get_tree_bdev(fc, squashfs_fill_super);
+}
+
+static int squashfs_reconfigure(struct fs_context *fc)
+{
+	sync_filesystem(fc->root->d_sb);
+	fc->sb_flags |= SB_RDONLY;
+	return 0;
+}
+
+static const struct fs_context_operations squashfs_context_ops = {
+	.get_tree	= squashfs_get_tree,
+	.reconfigure	= squashfs_reconfigure,
+};
+
+static int squashfs_init_fs_context(struct fs_context *fc)
+{
+	fc->ops = &squashfs_context_ops;
+	return 0;
+}
 
 static int squashfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 {
@@ -360,14 +387,6 @@ static int squashfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 }
 
 
-static int squashfs_remount(struct super_block *sb, int *flags, char *data)
-{
-	sync_filesystem(sb);
-	*flags |= SB_RDONLY;
-	return 0;
-}
-
-
 static void squashfs_put_super(struct super_block *sb)
 {
 	if (sb->s_fs_info) {
@@ -386,14 +405,6 @@ static void squashfs_put_super(struct super_block *sb)
 	}
 }
 
-
-static struct dentry *squashfs_mount(struct file_system_type *fs_type,
-				int flags, const char *dev_name, void *data)
-{
-	return mount_bdev(fs_type, flags, dev_name, data, squashfs_fill_super);
-}
-
-
 static struct kmem_cache *squashfs_inode_cachep;
 
 
@@ -470,7 +481,7 @@ static void squashfs_free_inode(struct inode *inode)
 static struct file_system_type squashfs_fs_type = {
 	.owner = THIS_MODULE,
 	.name = "squashfs",
-	.mount = squashfs_mount,
+	.init_fs_context = squashfs_init_fs_context,
 	.kill_sb = kill_block_super,
 	.fs_flags = FS_REQUIRES_DEV
 };
@@ -481,7 +492,6 @@ static const struct super_operations squashfs_super_ops = {
 	.free_inode = squashfs_free_inode,
 	.statfs = squashfs_statfs,
 	.put_super = squashfs_put_super,
-	.remount_fs = squashfs_remount
 };
 
 module_init(init_squashfs_fs);