]> www.pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - fs/btrfs/super.c
btrfs: fix for write_super_lockfs/unlockfs error handling
[linux-2.6-omap-h63xx.git] / fs / btrfs / super.c
index 431fdf144b585709afe6f6f50f81df2f8b0021e6..0a14b495532fcc901d3c3baaa29cb4753d327d7f 100644 (file)
@@ -37,6 +37,8 @@
 #include <linux/ctype.h>
 #include <linux/namei.h>
 #include <linux/miscdevice.h>
+#include <linux/version.h>
+#include "compat.h"
 #include "ctree.h"
 #include "disk-io.h"
 #include "transaction.h"
 
 static struct super_operations btrfs_super_ops;
 
-static void btrfs_put_super (struct super_block * sb)
+static void btrfs_put_super(struct super_block *sb)
 {
        struct btrfs_root *root = btrfs_sb(sb);
-       struct btrfs_fs_info *fs = root->fs_info;
        int ret;
 
        ret = close_ctree(root);
-       if (ret) {
-               printk("close ctree returns %d\n", ret);
-       }
-       btrfs_sysfs_del_super(fs);
        sb->s_fs_info = NULL;
 }
 
@@ -240,7 +237,7 @@ int btrfs_parse_options(struct btrfs_root *root, char *options)
  * All other options will be parsed on much later in the mount process and
  * only when we need to allocate a new super block.
  */
-static int btrfs_parse_early_options(const char *options, int flags,
+static int btrfs_parse_early_options(const char *options, fmode_t flags,
                void *holder, char **subvol_name,
                struct btrfs_fs_devices **fs_devices)
 {
@@ -285,23 +282,23 @@ static int btrfs_parse_early_options(const char *options, int flags,
  out:
        /*
         * If no subvolume name is specified we use the default one.  Allocate
-        * a copy of the string "default" here so that code later in the
+        * a copy of the string "." here so that code later in the
         * mount path doesn't care if it's the default volume or another one.
         */
        if (!*subvol_name) {
-               *subvol_name = kstrdup("default", GFP_KERNEL);
+               *subvol_name = kstrdup(".", GFP_KERNEL);
                if (!*subvol_name)
                        return -ENOMEM;
        }
        return error;
 }
 
-static int btrfs_fill_super(struct super_block * sb,
+static int btrfs_fill_super(struct super_block *sb,
                            struct btrfs_fs_devices *fs_devices,
-                           void * data, int silent)
+                           void *data, int silent)
 {
-       struct inode * inode;
-       struct dentry * root_dentry;
+       struct inode *inode;
+       struct dentry *root_dentry;
        struct btrfs_super_block *disk_super;
        struct btrfs_root *tree_root;
        struct btrfs_inode *bi;
@@ -323,12 +320,12 @@ static int btrfs_fill_super(struct super_block * sb,
        }
        sb->s_fs_info = tree_root;
        disk_super = &tree_root->fs_info->super_copy;
-       inode = btrfs_iget_locked(sb, btrfs_super_root_dir(disk_super),
-                                 tree_root);
+       inode = btrfs_iget_locked(sb, BTRFS_FIRST_FREE_OBJECTID,
+                                 tree_root->fs_info->fs_root);
        bi = BTRFS_I(inode);
        bi->location.objectid = inode->i_ino;
        bi->location.offset = 0;
-       bi->root = tree_root;
+       bi->root = tree_root->fs_info->fs_root;
 
        btrfs_set_key_type(&bi->location, BTRFS_INODE_ITEM_KEY);
 
@@ -347,11 +344,12 @@ static int btrfs_fill_super(struct super_block * sb,
                err = -ENOMEM;
                goto fail_close;
        }
-
+#if 0
        /* this does the super kobj at the same time */
        err = btrfs_sysfs_add_super(tree_root->fs_info);
        if (err)
                goto fail_close;
+#endif
 
        sb->s_root = root_dentry;
 
@@ -370,11 +368,18 @@ int btrfs_sync_fs(struct super_block *sb, int wait)
        int ret;
        root = btrfs_sb(sb);
 
+       if (sb->s_flags & MS_RDONLY)
+               return 0;
+
        sb->s_dirt = 0;
        if (!wait) {
                filemap_flush(root->fs_info->btree_inode->i_mapping);
                return 0;
        }
+
+       btrfs_start_delalloc_inodes(root);
+       btrfs_wait_ordered_extents(root, 0);
+
        btrfs_clean_old_snapshots(root);
        trans = btrfs_start_transaction(root, 1);
        ret = btrfs_commit_transaction(trans, root);
@@ -409,21 +414,30 @@ static int btrfs_get_sb(struct file_system_type *fs_type, int flags,
        struct super_block *s;
        struct dentry *root;
        struct btrfs_fs_devices *fs_devices = NULL;
+       fmode_t mode = FMODE_READ;
        int error = 0;
 
-       error = btrfs_parse_early_options(data, flags, fs_type,
+       if (!(flags & MS_RDONLY))
+               mode |= FMODE_WRITE;
+
+       error = btrfs_parse_early_options(data, mode, fs_type,
                                          &subvol_name, &fs_devices);
        if (error)
-               goto error;
+               return error;
 
-       error = btrfs_scan_one_device(dev_name, flags, fs_type, &fs_devices);
+       error = btrfs_scan_one_device(dev_name, mode, fs_type, &fs_devices);
        if (error)
                goto error_free_subvol_name;
 
-       error = btrfs_open_devices(fs_devices, flags, fs_type);
+       error = btrfs_open_devices(fs_devices, mode, fs_type);
        if (error)
                goto error_free_subvol_name;
 
+       if (!(flags & MS_RDONLY) && fs_devices->rw_devices == 0) {
+               error = -EACCES;
+               goto error_close_devices;
+       }
+
        bdev = fs_devices->latest_bdev;
        s = sget(fs_type, btrfs_test_super, set_anon_super, fs_devices);
        if (IS_ERR(s))
@@ -434,9 +448,10 @@ static int btrfs_get_sb(struct file_system_type *fs_type, int flags,
                        up_write(&s->s_umount);
                        deactivate_super(s);
                        error = -EBUSY;
-                       goto error_bdev;
+                       goto error_close_devices;
                }
 
+               btrfs_close_devices(fs_devices);
        } else {
                char b[BDEVNAME_SIZE];
 
@@ -447,7 +462,7 @@ static int btrfs_get_sb(struct file_system_type *fs_type, int flags,
                if (error) {
                        up_write(&s->s_umount);
                        deactivate_super(s);
-                       goto error;
+                       goto error_free_subvol_name;
                }
 
                btrfs_sb(s)->fs_info->bdev_holder = fs_type;
@@ -458,20 +473,22 @@ static int btrfs_get_sb(struct file_system_type *fs_type, int flags,
                root = dget(s->s_root);
        else {
                mutex_lock(&s->s_root->d_inode->i_mutex);
-               root = lookup_one_len(subvol_name, s->s_root, strlen(subvol_name));
+               root = lookup_one_len(subvol_name, s->s_root,
+                                     strlen(subvol_name));
                mutex_unlock(&s->s_root->d_inode->i_mutex);
+
                if (IS_ERR(root)) {
                        up_write(&s->s_umount);
                        deactivate_super(s);
                        error = PTR_ERR(root);
-                       goto error;
+                       goto error_free_subvol_name;
                }
                if (!root->d_inode) {
                        dput(root);
                        up_write(&s->s_umount);
                        deactivate_super(s);
                        error = -ENXIO;
-                       goto error;
+                       goto error_free_subvol_name;
                }
        }
 
@@ -483,14 +500,45 @@ static int btrfs_get_sb(struct file_system_type *fs_type, int flags,
 
 error_s:
        error = PTR_ERR(s);
-error_bdev:
+error_close_devices:
        btrfs_close_devices(fs_devices);
 error_free_subvol_name:
        kfree(subvol_name);
-error:
        return error;
 }
 
+static int btrfs_remount(struct super_block *sb, int *flags, char *data)
+{
+       struct btrfs_root *root = btrfs_sb(sb);
+       int ret;
+
+       if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
+               return 0;
+
+       if (*flags & MS_RDONLY) {
+               sb->s_flags |= MS_RDONLY;
+
+               ret =  btrfs_commit_super(root);
+               WARN_ON(ret);
+       } else {
+               if (root->fs_info->fs_devices->rw_devices == 0)
+                       return -EACCES;
+
+               if (btrfs_super_log_root(&root->fs_info->super_copy) != 0)
+                       return -EINVAL;
+
+               ret = btrfs_cleanup_reloc_trees(root);
+               WARN_ON(ret);
+
+               ret = btrfs_cleanup_fs_roots(root->fs_info);
+               WARN_ON(ret);
+
+               sb->s_flags &= ~MS_RDONLY;
+       }
+
+       return 0;
+}
+
 static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 {
        struct btrfs_root *root = btrfs_sb(dentry->d_sb);
@@ -505,8 +553,9 @@ static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf)
        buf->f_bavail = buf->f_bfree;
        buf->f_bsize = dentry->d_sb->s_blocksize;
        buf->f_type = BTRFS_SUPER_MAGIC;
+
        /* We treat it as constant endianness (it doesn't matter _which_)
-          because we want the fsid to come out the same whether mounted 
+          because we want the fsid to come out the same whether mounted
           on a big-endian or little-endian host */
        buf->f_fsid.val[0] = be32_to_cpu(fsid[0]) ^ be32_to_cpu(fsid[2]);
        buf->f_fsid.val[1] = be32_to_cpu(fsid[1]) ^ be32_to_cpu(fsid[3]);
@@ -536,6 +585,9 @@ static long btrfs_control_ioctl(struct file *file, unsigned int cmd,
        int ret = 0;
        int len;
 
+       if (!capable(CAP_SYS_ADMIN))
+               return -EPERM;
+
        vol = kmalloc(sizeof(*vol), GFP_KERNEL);
        if (copy_from_user(vol, (void __user *)arg, sizeof(*vol))) {
                ret = -EFAULT;
@@ -544,7 +596,7 @@ static long btrfs_control_ioctl(struct file *file, unsigned int cmd,
        len = strnlen(vol->name, BTRFS_PATH_NAME_MAX);
        switch (cmd) {
        case BTRFS_IOC_SCAN_DEV:
-               ret = btrfs_scan_one_device(vol->name, MS_RDONLY,
+               ret = btrfs_scan_one_device(vol->name, FMODE_READ,
                                            &btrfs_fs_type, &fs_devices);
                break;
        }
@@ -553,18 +605,20 @@ out:
        return ret;
 }
 
-static void btrfs_write_super_lockfs(struct super_block *sb)
+static int btrfs_freeze(struct super_block *sb)
 {
        struct btrfs_root *root = btrfs_sb(sb);
        mutex_lock(&root->fs_info->transaction_kthread_mutex);
        mutex_lock(&root->fs_info->cleaner_mutex);
+       return 0;
 }
 
-static void btrfs_unlockfs(struct super_block *sb)
+static int btrfs_unfreeze(struct super_block *sb)
 {
        struct btrfs_root *root = btrfs_sb(sb);
        mutex_unlock(&root->fs_info->cleaner_mutex);
        mutex_unlock(&root->fs_info->transaction_kthread_mutex);
+       return 0;
 }
 
 static struct super_operations btrfs_super_ops = {
@@ -578,8 +632,9 @@ static struct super_operations btrfs_super_ops = {
        .alloc_inode    = btrfs_alloc_inode,
        .destroy_inode  = btrfs_destroy_inode,
        .statfs         = btrfs_statfs,
-       .write_super_lockfs = btrfs_write_super_lockfs,
-       .unlockfs       = btrfs_unlockfs,
+       .remount_fs     = btrfs_remount,
+       .freeze_fs      = btrfs_freeze,
+       .unfreeze_fs    = btrfs_unfreeze,
 };
 
 static const struct file_operations btrfs_ctl_fops = {
@@ -599,10 +654,10 @@ static int btrfs_interface_init(void)
        return misc_register(&btrfs_misc);
 }
 
-void btrfs_interface_exit(void)
+static void btrfs_interface_exit(void)
 {
        if (misc_deregister(&btrfs_misc) < 0)
-               printk("misc_deregister failed for control device");
+               printk(KERN_INFO "misc_deregister failed for control device");
 }
 
 static int __init init_btrfs_fs(void)