diff options
| -rw-r--r-- | drivers/mtd/Makefile | 3 | ||||
| -rw-r--r-- | drivers/mtd/mtdsuper.c | 232 | ||||
| -rw-r--r-- | fs/jffs2/super.c | 194 | ||||
| -rw-r--r-- | include/linux/fs.h | 1 | ||||
| -rw-r--r-- | include/linux/mtd/super.h | 30 |
5 files changed, 283 insertions, 177 deletions
diff --git a/drivers/mtd/Makefile b/drivers/mtd/Makefile index 9205540..451adcc 100644 --- a/drivers/mtd/Makefile +++ b/drivers/mtd/Makefile @@ -1,10 +1,9 @@ # # Makefile for the memory technology device drivers. # -# $Id: Makefile.common,v 1.7 2005/07/11 10:39:27 gleixner Exp $ # Core functionality. -mtd-y := mtdcore.o +mtd-y := mtdcore.o mtdsuper.o mtd-$(CONFIG_MTD_PARTITIONS) += mtdpart.o obj-$(CONFIG_MTD) += $(mtd-y) diff --git a/drivers/mtd/mtdsuper.c b/drivers/mtd/mtdsuper.c new file mode 100644 index 0000000..a279540 --- /dev/null +++ b/drivers/mtd/mtdsuper.c @@ -0,0 +1,232 @@ +/* MTD-based superblock management + * + * Copyright © 2001-2007 Red Hat, Inc. All Rights Reserved. + * Written by: David Howells <dhowells@redhat.com> + * David Woodhouse <dwmw2@infradead.org> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include <linux/mtd/super.h> +#include <linux/namei.h> +#include <linux/ctype.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) +{ + struct mtd_info *mtd = _mtd; + + if (sb->s_mtd == mtd) { + DEBUG(2, "MTDSB: Match on device %d (\"%s\")\n", + mtd->index, mtd->name); + return 1; + } + + DEBUG(2, "MTDSB: No match, device %d (\"%s\"), device %d (\"%s\")\n", + sb->s_mtd->index, sb->s_mtd->name, mtd->index, mtd->name); + return 0; +} + +/* + * 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) +{ + struct mtd_info *mtd = _mtd; + + sb->s_mtd = mtd; + sb->s_dev = MKDEV(MTD_BLOCK_MAJOR, mtd->index); + return 0; +} + +/* + * get a superblock on an MTD-backed filesystem + */ +static int get_sb_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), + struct vfsmount *mnt) +{ + struct super_block *sb; + int ret; + + sb = sget(fs_type, get_sb_mtd_compare, get_sb_mtd_set, mtd); + if (IS_ERR(sb)) + goto out_error; + + if (sb->s_root) + goto already_mounted; + + /* fresh new superblock */ + DEBUG(1, "MTDSB: New superblock for device %d (\"%s\")\n", + mtd->index, mtd->name); + + ret = fill_super(sb, data, flags & MS_SILENT ? 1 : 0); + if (ret < 0) { + up_write(&sb->s_umount); + deactivate_super(sb); + return ret; + } + + /* go */ + sb->s_flags |= MS_ACTIVE; + return simple_set_mnt(mnt, sb); + + /* new mountpoint for an already mounted superblock */ +already_mounted: + DEBUG(1, "MTDSB: Device %d (\"%s\") is already mounted\n", + mtd->index, mtd->name); + ret = simple_set_mnt(mnt, sb); + goto out_put; + +out_error: + ret = PTR_ERR(sb); +out_put: + put_mtd_device(mtd); + return ret; +} + +/* + * get a superblock on an MTD-backed filesystem by MTD device number + */ +static int get_sb_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), + struct vfsmount *mnt) +{ + struct mtd_info *mtd; + + mtd = get_mtd_device(NULL, mtdnr); + if (!mtd) { + DEBUG(0, "MTDSB: Device #%u doesn't appear to exist\n", mtdnr); + return -EINVAL; + } + + return get_sb_mtd_aux(fs_type, flags, dev_name, data, mtd, fill_super, + mnt); +} + +/* + * set up an MTD-based superblock + */ +int get_sb_mtd(struct file_system_type *fs_type, int flags, + const char *dev_name, void *data, + int (*fill_super)(struct super_block *, void *, int), + struct vfsmount *mnt) +{ + struct nameidata nd; + int mtdnr, ret; + + if (!dev_name) + return -EINVAL; + + DEBUG(2, "MTDSB: dev_name \"%s\"\n", dev_name); + + /* 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] == ':') { + struct mtd_info *mtd; + + /* mount by MTD device name */ + DEBUG(1, "MTDSB: mtd:%%s, name \"%s\"\n", + dev_name + 4); + + for (mtdnr = 0; mtdnr < MAX_MTD_DEVICES; mtdnr++) { + mtd = get_mtd_device(NULL, mtdnr); + if (mtd) { + if (!strcmp(mtd->name, dev_name + 4)) + return get_sb_mtd_aux( + fs_type, flags, + dev_name, data, mtd, + fill_super, mnt); + + put_mtd_device(mtd); + } + } + + printk(KERN_NOTICE "MTD:" + " MTD device with name \"%s\" not found.\n", + dev_name + 4); + + } else if (isdigit(dev_name[3])) { + /* mount by MTD device number name */ + char *endptr; + + mtdnr = simple_strtoul(dev_name + 3, &endptr, 0); + if (!*endptr) { + /* It was a valid number */ + DEBUG(1, "MTDSB: mtd%%d, mtdnr %d\n", + mtdnr); + return get_sb_mtd_nr(fs_type, flags, + dev_name, data, + mtdnr, fill_super, mnt); + } + } + } + + /* try the old way - the hack where we allowed users to mount + * /dev/mtdblock$(n) but didn't actually _use_ the blockdev + */ + ret = path_lookup(dev_name, LOOKUP_FOLLOW, &nd); + + DEBUG(1, "MTDSB: path_lookup() returned %d, inode %p\n", + ret, nd.dentry ? nd.dentry->d_inode : NULL); + + if (ret) + return ret; + + ret = -EINVAL; + + if (!S_ISBLK(nd.dentry->d_inode->i_mode)) + goto out; + + if (nd.mnt->mnt_flags & MNT_NODEV) { + ret = -EACCES; + goto out; + } + + if (imajor(nd.dentry->d_inode) != MTD_BLOCK_MAJOR) + goto not_an_MTD_device; + + mtdnr = iminor(nd.dentry->d_inode); + path_release(&nd); + + return get_sb_mtd_nr(fs_type, flags, dev_name, data, mtdnr, fill_super, + mnt); + +not_an_MTD_device: + if (!(flags & MS_SILENT)) + printk(KERN_NOTICE + "MTD: Attempt to mount non-MTD device \"%s\"\n", + dev_name); +out: + path_release(&nd); + return ret; + +} + +EXPORT_SYMBOL_GPL(get_sb_mtd); + +/* + * destroy an MTD-based superblock + */ +void kill_mtd_super(struct super_block *sb) +{ + generic_shutdown_super(sb); + put_mtd_device(sb->s_mtd); + sb->s_mtd = NULL; +} + +EXPORT_SYMBOL_GPL(kill_mtd_super); diff --git a/fs/jffs2/super.c b/fs/jffs2/super.c index e51164a..e3c69e6 100644 --- a/fs/jffs2/super.c +++ b/fs/jffs2/super.c @@ -19,7 +19,7 @@ #include <linux/mount.h> #include <linux/jffs2.h> #include <linux/pagemap.h> -#include <linux/mtd/mtd.h> +#include <linux/mtd/super.h> #include <linux/ctype.h> #include <linux/namei.h> #include "compr.h" @@ -78,69 +78,27 @@ static const struct super_operations jffs2_super_operations = .sync_fs = jffs2_sync_fs, }; -static int jffs2_sb_compare(struct super_block *sb, void *data) -{ - struct jffs2_sb_info *p = data; - struct jffs2_sb_info *c = JFFS2_SB_INFO(sb); - - /* The superblocks are considered to be equivalent if the underlying MTD - device is the same one */ - if (c->mtd == p->mtd) { - D1(printk(KERN_DEBUG "jffs2_sb_compare: match on device %d (\"%s\")\n", p->mtd->index, p->mtd->name)); - return 1; - } else { - D1(printk(KERN_DEBUG "jffs2_sb_compare: No match, device %d (\"%s\"), device %d (\"%s\")\n", - c->mtd->index, c->mtd->name, p->mtd->index, p->mtd->name)); - return 0; - } -} - -static int jffs2_sb_set(struct super_block *sb, void *data) -{ - struct jffs2_sb_info *p = data; - - /* For persistence of NFS exports etc. we use the same s_dev - each time we mount the device, don't just use an anonymous - device */ - sb->s_fs_info = p; - p->os_priv = sb; - sb->s_dev = MKDEV(MTD_BLOCK_MAJOR, p->mtd->index); - - return 0; -} - -static int jffs2_get_sb_mtd(struct file_system_type *fs_type, - int flags, const char *dev_name, - void *data, struct mtd_info *mtd, - struct vfsmount *mnt) +/* + * fill in the superblock + */ +static int jffs2_fill_super(struct super_block *sb, void *data, int silent) { - struct super_block *sb; struct jffs2_sb_info *c; - int ret; + + D1(printk(KERN_DEBUG "jffs2_get_sb_mtd():" + " New superblock for device %d (\"%s\")\n", + sb->s_mtd->index, sb->s_mtd->name)); c = kzalloc(sizeof(*c), GFP_KERNEL); if (!c) return -ENOMEM; - c->mtd = mtd; - - sb = sget(fs_type, jffs2_sb_compare, jffs2_sb_set, c); - - if (IS_ERR(sb)) - goto out_error; - - if (sb->s_root) { - /* New mountpoint for JFFS2 which is already mounted */ - D1(printk(KERN_DEBUG "jffs2_get_sb_mtd(): Device %d (\"%s\") is already mounted\n", - mtd->index, mtd->name)); - ret = simple_set_mnt(mnt, sb); - goto out_put; - } - D1(printk(KERN_DEBUG "jffs2_get_sb_mtd(): New superblock for device %d (\"%s\")\n", - mtd->index, mtd->name)); + c->mtd = sb->s_mtd; + c->os_priv = sb; + sb->s_fs_info = c; - /* Initialize JFFS2 superblock locks, the further initialization will be - * done later */ + /* Initialize JFFS2 superblock locks, the further initialization will + * be done later */ init_MUTEX(&c->alloc_sem); init_MUTEX(&c->erase_free_sem); init_waitqueue_head(&c->erase_wait); @@ -149,133 +107,20 @@ static int jffs2_get_sb_mtd(struct file_system_type *fs_type, spin_lock_init(&c->inocache_lock); sb->s_op = &jffs2_super_operations; - sb->s_flags = flags | MS_NOATIME; + sb->s_flags = sb->s_flags | MS_NOATIME; sb->s_xattr = jffs2_xattr_handlers; #ifdef CONFIG_JFFS2_FS_POSIX_ACL sb->s_flags |= MS_POSIXACL; #endif - ret = jffs2_do_fill_super(sb, data, flags & MS_SILENT ? 1 : 0); - - if (ret) { - /* Failure case... */ - up_write(&sb->s_umount); - deactivate_super(sb); - return ret; - } - - sb->s_flags |= MS_ACTIVE; - return simple_set_mnt(mnt, sb); - -out_error: - ret = PTR_ERR(sb); - out_put: - kfree(c); - put_mtd_device(mtd); - - return ret; -} - -static int jffs2_get_sb_mtdnr(struct file_system_type *fs_type, - int flags, const char *dev_name, - void *data, int mtdnr, - struct vfsmount *mnt) -{ - struct mtd_info *mtd; - - mtd = get_mtd_device(NULL, mtdnr); - if (IS_ERR(mtd)) { - D1(printk(KERN_DEBUG "jffs2: MTD device #%u doesn't appear to exist\n", mtdnr)); - return PTR_ERR(mtd); - } - - return jffs2_get_sb_mtd(fs_type, flags, dev_name, data, mtd, mnt); + return jffs2_do_fill_super(sb, data, silent); } static int jffs2_get_sb(struct file_system_type *fs_type, int flags, const char *dev_name, void *data, struct vfsmount *mnt) { - int err; - struct nameidata nd; - int mtdnr; - - if (!dev_name) - return -EINVAL; - - D1(printk(KERN_DEBUG "jffs2_get_sb(): dev_name \"%s\"\n", dev_name)); - - /* The preferred way of mounting in future; especially when - CONFIG_BLK_DEV is implemented - 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. */ - - /* FIXME: How to do the root fs this way? */ - - if (dev_name[0] == 'm' && dev_name[1] == 't' && dev_name[2] == 'd') { - /* Probably mounting without the blkdev crap */ - if (dev_name[3] == ':') { - struct mtd_info *mtd; - - /* Mount by MTD device name */ - D1(printk(KERN_DEBUG "jffs2_get_sb(): mtd:%%s, name \"%s\"\n", dev_name+4)); - for (mtdnr = 0; mtdnr < MAX_MTD_DEVICES; mtdnr++) { - mtd = get_mtd_device(NULL, mtdnr); - if (!IS_ERR(mtd)) { - if (!strcmp(mtd->name, dev_name+4)) - return jffs2_get_sb_mtd(fs_type, flags, dev_name, data, mtd, mnt); - put_mtd_device(mtd); - } - } - printk(KERN_NOTICE "jffs2_get_sb(): MTD device with name \"%s\" not found.\n", dev_name+4); - } else if (isdigit(dev_name[3])) { - /* Mount by MTD device number name */ - char *endptr; - - mtdnr = simple_strtoul(dev_name+3, &endptr, 0); - if (!*endptr) { - /* It was a valid number */ - D1(printk(KERN_DEBUG "jffs2_get_sb(): mtd%%d, mtdnr %d\n", mtdnr)); - return jffs2_get_sb_mtdnr(fs_type, flags, dev_name, data, mtdnr, mnt); - } - } - } - - /* Try the old way - the hack where we allowed users to mount - /dev/mtdblock$(n) but didn't actually _use_ the blkdev */ - - err = path_lookup(dev_name, LOOKUP_FOLLOW, &nd); - - D1(printk(KERN_DEBUG "jffs2_get_sb(): path_lookup() returned %d, inode %p\n", - err, nd.dentry->d_inode)); - - if (err) - return err; - - err = -EINVAL; - - if (!S_ISBLK(nd.dentry->d_inode->i_mode)) - goto out; - - if (nd.mnt->mnt_flags & MNT_NODEV) { - err = -EACCES; - goto out; - } - - if (imajor(nd.dentry->d_inode) != MTD_BLOCK_MAJOR) { - if (!(flags & MS_SILENT)) - printk(KERN_NOTICE "Attempt to mount non-MTD device \"%s\" as JFFS2\n", - dev_name); - goto out; - } - - mtdnr = iminor(nd.dentry->d_inode); - path_release(&nd); - - return jffs2_get_sb_mtdnr(fs_type, flags, dev_name, data, mtdnr, mnt); - -out: - path_release(&nd); - return err; + return get_sb_mtd(fs_type, flags, dev_name, data, jffs2_fill_super, + mnt); } static void jffs2_put_super (struct super_block *sb) @@ -310,8 +155,7 @@ static void jffs2_kill_sb(struct super_block *sb) struct jffs2_sb_info *c = JFFS2_SB_INFO(sb); if (!(sb->s_flags & MS_RDONLY)) jffs2_stop_garbage_collect_thread(c); - generic_shutdown_super(sb); - put_mtd_device(c->mtd); + kill_mtd_super(sb); kfree(c); } diff --git a/include/linux/fs.h b/include/linux/fs.h index 095a9c9..151739a 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -937,6 +937,7 @@ struct super_block { struct list_head s_files; struct block_device *s_bdev; + struct mtd_info *s_mtd; struct list_head s_instances; struct quota_info s_dquot; /* Diskquota specific options */ diff --git a/include/linux/mtd/super.h b/include/linux/mtd/super.h new file mode 100644 index 0000000..4016dd6 --- /dev/null +++ b/include/linux/mtd/super.h @@ -0,0 +1,30 @@ +/* MTD-based superblock handling + * + * Copyright © 2006 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#ifndef __MTD_SUPER_H__ +#define __MTD_SUPER_H__ + +#ifdef __KERNEL__ + +#include <linux/mtd/mtd.h> +#include <linux/fs.h> +#include <linux/mount.h> + +extern int get_sb_mtd(struct file_system_type *fs_type, int flags, + const char *dev_name, void *data, + int (*fill_super)(struct super_block *, void *, int), + struct vfsmount *mnt); +extern void kill_mtd_super(struct super_block *sb); + + +#endif /* __KERNEL__ */ + +#endif /* __MTD_SUPER_H__ */ |