1 files changed, 80 insertions, 94 deletions

diff --git a/drivers/mtd/mtdsuper.c b/drivers/mtd/mtdsuper.c
index 4f042a3653ce..c3e2098372f2 100644
--- a/drivers/mtd/mtdsuper.c
+++ b/drivers/mtd/mtdsuper.c
@@ -15,112 +15,109 @@
 #include <linux/slab.h>
 #include <linux/major.h>
 #include <linux/backing-dev.h>
+#include <linux/fs_context.h>
+#include "mtdcore.h"
 
 /*
  * compare superblocks to see if they're equivalent
  * - they are if the underlying MTD device is the same
  */
-static int get_sb_mtd_compare(struct super_block *sb, void *_mtd)
+static int mtd_test_super(struct super_block *sb, struct fs_context *fc)
 {
-	struct mtd_info *mtd = _mtd;
+	struct mtd_info *mtd = fc->sget_key;
 
-	if (sb->s_mtd == mtd) {
+	if (sb->s_mtd == fc->sget_key) {
 		pr_debug("MTDSB: Match on device %d (\"%s\")\n",
-		      mtd->index, mtd->name);
+			 mtd->index, mtd->name);
 		return 1;
 	}
 
 	pr_debug("MTDSB: No match, device %d (\"%s\"), device %d (\"%s\")\n",
-	      sb->s_mtd->index, sb->s_mtd->name, mtd->index, mtd->name);
+		 sb->s_mtd->index, sb->s_mtd->name, mtd->index, mtd->name);
 	return 0;
 }
 
-extern struct backing_dev_info *mtd_bdi;
-
 /*
  * mark the superblock by the MTD device it is using
  * - set the device number to be the correct MTD block device for pesuperstence
  *   of NFS exports
  */
-static int get_sb_mtd_set(struct super_block *sb, void *_mtd)
+static int mtd_set_super(struct super_block *sb, struct fs_context *fc)
 {
-	struct mtd_info *mtd = _mtd;
-
-	sb->s_mtd = mtd;
-	sb->s_dev = MKDEV(MTD_BLOCK_MAJOR, mtd->index);
+	sb->s_mtd = fc->sget_key;
+	sb->s_dev = MKDEV(MTD_BLOCK_MAJOR, sb->s_mtd->index);
 	sb->s_bdi = bdi_get(mtd_bdi);
-
 	return 0;
 }
 
 /*
  * get a superblock on an MTD-backed filesystem
  */
-static struct dentry *mount_mtd_aux(struct file_system_type *fs_type, int flags,
-			  const char *dev_name, void *data,
-			  struct mtd_info *mtd,
-			  int (*fill_super)(struct super_block *, void *, int))
+static int mtd_get_sb(struct fs_context *fc,
+		      struct mtd_info *mtd,
+		      int (*fill_super)(struct super_block *,
+					struct fs_context *))
 {
 	struct super_block *sb;
 	int ret;
 
-	sb = sget(fs_type, get_sb_mtd_compare, get_sb_mtd_set, flags, mtd);
+	fc->sget_key = mtd;
+	sb = sget_fc(fc, mtd_test_super, mtd_set_super);
 	if (IS_ERR(sb))
-		goto out_error;
-
-	if (sb->s_root)
-		goto already_mounted;
-
-	/* fresh new superblock */
-	pr_debug("MTDSB: New superblock for device %d (\"%s\")\n",
-	      mtd->index, mtd->name);
-
-	ret = fill_super(sb, data, flags & SB_SILENT ? 1 : 0);
-	if (ret < 0) {
-		deactivate_locked_super(sb);
-		return ERR_PTR(ret);
+		return PTR_ERR(sb);
+
+	if (sb->s_root) {
+		/* new mountpoint for an already mounted superblock */
+		pr_debug("MTDSB: Device %d (\"%s\") is already mounted\n",
+			 mtd->index, mtd->name);
+		put_mtd_device(mtd);
+	} else {
+		/* fresh new superblock */
+		pr_debug("MTDSB: New superblock for device %d (\"%s\")\n",
+			 mtd->index, mtd->name);
+
+		ret = fill_super(sb, fc);
+		if (ret < 0)
+			goto error_sb;
+
+		sb->s_flags |= SB_ACTIVE;
 	}
 
-	/* go */
-	sb->s_flags |= SB_ACTIVE;
-	return dget(sb->s_root);
-
-	/* new mountpoint for an already mounted superblock */
-already_mounted:
-	pr_debug("MTDSB: Device %d (\"%s\") is already mounted\n",
-	      mtd->index, mtd->name);
-	put_mtd_device(mtd);
-	return dget(sb->s_root);
+	BUG_ON(fc->root);
+	fc->root = dget(sb->s_root);
+	return 0;
 
-out_error:
-	put_mtd_device(mtd);
-	return ERR_CAST(sb);
+error_sb:
+	deactivate_locked_super(sb);
+	return ret;
 }
 
 /*
  * get a superblock on an MTD-backed filesystem by MTD device number
  */
-static struct dentry *mount_mtd_nr(struct file_system_type *fs_type, int flags,
-			 const char *dev_name, void *data, int mtdnr,
-			 int (*fill_super)(struct super_block *, void *, int))
+static int mtd_get_sb_by_nr(struct fs_context *fc, int mtdnr,
+			    int (*fill_super)(struct super_block *,
+					      struct fs_context *))
 {
 	struct mtd_info *mtd;
 
 	mtd = get_mtd_device(NULL, mtdnr);
 	if (IS_ERR(mtd)) {
-		pr_debug("MTDSB: Device #%u doesn't appear to exist\n", mtdnr);
-		return ERR_CAST(mtd);
+		errorf(fc, "MTDSB: Device #%u doesn't appear to exist\n", mtdnr);
+		return PTR_ERR(mtd);
 	}
 
-	return mount_mtd_aux(fs_type, flags, dev_name, data, mtd, fill_super);
+	return mtd_get_sb(fc, mtd, fill_super);
 }
 
-/*
- * set up an MTD-based superblock
+/**
+ * get_tree_mtd - Get a superblock based on a single MTD device
+ * @fc: The filesystem context holding the parameters
+ * @fill_super: Helper to initialise a new superblock
  */
-struct dentry *mount_mtd(struct file_system_type *fs_type, int flags,
-	       const char *dev_name, void *data,
-	       int (*fill_super)(struct super_block *, void *, int))
+int get_tree_mtd(struct fs_context *fc,
+	      int (*fill_super)(struct super_block *sb,
+				struct fs_context *fc))
 {
 #ifdef CONFIG_BLOCK
 	struct block_device *bdev;
@@ -128,46 +125,42 @@ struct dentry *mount_mtd(struct file_system_type *fs_type, int flags,
 #endif
 	int mtdnr;
 
-	if (!dev_name)
-		return ERR_PTR(-EINVAL);
+	if (!fc->source)
+		return invalf(fc, "No source specified");
 
-	pr_debug("MTDSB: dev_name \"%s\"\n", dev_name);
+	pr_debug("MTDSB: dev_name \"%s\"\n", fc->source);
 
 	/* the preferred way of mounting in future; especially when
 	 * CONFIG_BLOCK=n - we specify the underlying MTD device by number or
 	 * by name, so that we don't require block device support to be present
-	 * in the kernel. */
-	if (dev_name[0] == 'm' && dev_name[1] == 't' && dev_name[2] == 'd') {
-		if (dev_name[3] == ':') {
+	 * in the kernel.
+	 */
+	if (fc->source[0] == 'm' &&
+	    fc->source[1] == 't' &&
+	    fc->source[2] == 'd') {
+		if (fc->source[3] == ':') {
 			struct mtd_info *mtd;
 
 			/* mount by MTD device name */
 			pr_debug("MTDSB: mtd:%%s, name \"%s\"\n",
-			      dev_name + 4);
+				 fc->source + 4);
 
-			mtd = get_mtd_device_nm(dev_name + 4);
+			mtd = get_mtd_device_nm(fc->source + 4);
 			if (!IS_ERR(mtd))
-				return mount_mtd_aux(
-					fs_type, flags,
-					dev_name, data, mtd,
-					fill_super);
+				return mtd_get_sb(fc, mtd, fill_super);
 
-			printk(KERN_NOTICE "MTD:"
-			       " MTD device with name \"%s\" not found.\n",
-			       dev_name + 4);
+			errorf(fc, "MTD: MTD device with name \"%s\" not found",
+			       fc->source + 4);
 
-		} else if (isdigit(dev_name[3])) {
+		} else if (isdigit(fc->source[3])) {
 			/* mount by MTD device number name */
 			char *endptr;
 
-			mtdnr = simple_strtoul(dev_name + 3, &endptr, 0);
+			mtdnr = simple_strtoul(fc->source + 3, &endptr, 0);
 			if (!*endptr) {
 				/* It was a valid number */
-				pr_debug("MTDSB: mtd%%d, mtdnr %d\n",
-				      mtdnr);
-				return mount_mtd_nr(fs_type, flags,
-						     dev_name, data,
-						     mtdnr, fill_super);
+				pr_debug("MTDSB: mtd%%d, mtdnr %d\n", mtdnr);
+				return mtd_get_sb_by_nr(fc, mtdnr, fill_super);
 			}
 		}
 	}
@@ -176,36 +169,29 @@ struct dentry *mount_mtd(struct file_system_type *fs_type, int flags,
 	/* try the old way - the hack where we allowed users to mount
 	 * /dev/mtdblock$(n) but didn't actually _use_ the blockdev
 	 */
-	bdev = lookup_bdev(dev_name);
+	bdev = lookup_bdev(fc->source);
 	if (IS_ERR(bdev)) {
 		ret = PTR_ERR(bdev);
-		pr_debug("MTDSB: lookup_bdev() returned %d\n", ret);
-		return ERR_PTR(ret);
+		errorf(fc, "MTD: Couldn't look up '%s': %d", fc->source, ret);
+		return ret;
 	}
 	pr_debug("MTDSB: lookup_bdev() returned 0\n");
 
-	ret = -EINVAL;
-
 	major = MAJOR(bdev->bd_dev);
 	mtdnr = MINOR(bdev->bd_dev);
 	bdput(bdev);
 
-	if (major != MTD_BLOCK_MAJOR)
-		goto not_an_MTD_device;
-
-	return mount_mtd_nr(fs_type, flags, dev_name, data, mtdnr, fill_super);
+	if (major == MTD_BLOCK_MAJOR)
+		return mtd_get_sb_by_nr(fc, mtdnr, fill_super);
 
-not_an_MTD_device:
 #endif /* CONFIG_BLOCK */
 
-	if (!(flags & SB_SILENT))
-		printk(KERN_NOTICE
-		       "MTD: Attempt to mount non-MTD device \"%s\"\n",
-		       dev_name);
-	return ERR_PTR(-EINVAL);
+	if (!(fc->sb_flags & SB_SILENT))
+		errorf(fc, "MTD: Attempt to mount non-MTD device \"%s\"",
+		       fc->source);
+	return -EINVAL;
 }
-
-EXPORT_SYMBOL_GPL(mount_mtd);
+EXPORT_SYMBOL_GPL(get_tree_mtd);
 
 /*
  * destroy an MTD-based superblock