Btrfs: Catch missed bios in the async bio submission thread
[safe/jmp/linux-2.6] / fs / btrfs / ioctl.c
index ec45b30..988fdc8 100644 (file)
@@ -38,9 +38,9 @@
 #include <linux/compat.h>
 #include <linux/bit_spinlock.h>
 #include <linux/security.h>
-#include <linux/version.h>
 #include <linux/xattr.h>
 #include <linux/vmalloc.h>
+#include "compat.h"
 #include "ctree.h"
 #include "disk-io.h"
 #include "transaction.h"
@@ -127,7 +127,6 @@ static noinline int create_subvol(struct btrfs_root *root,
        key.objectid = objectid;
        key.offset = 1;
        btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
-printk("inserting root objectid %Lu\n", objectid);
        ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
                                &root_item);
        if (ret)
@@ -146,13 +145,27 @@ printk("inserting root objectid %Lu\n", objectid);
                                    BTRFS_FT_DIR, index);
        if (ret)
                goto fail;
-#if 0
-       ret = btrfs_insert_inode_ref(trans, root->fs_info->tree_root,
-                            name, namelen, objectid,
-                            root->fs_info->sb->s_root->d_inode->i_ino, 0);
-       if (ret)
-               goto fail;
-#endif
+
+       btrfs_i_size_write(dir, dir->i_size + namelen * 2);
+       ret = btrfs_update_inode(trans, root, dir);
+       BUG_ON(ret);
+
+       /* add the backref first */
+       ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
+                                objectid, BTRFS_ROOT_BACKREF_KEY,
+                                root->root_key.objectid,
+                                dir->i_ino, index, name, namelen);
+
+       BUG_ON(ret);
+
+       /* now add the forward ref */
+       ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
+                                root->root_key.objectid, BTRFS_ROOT_REF_KEY,
+                                objectid,
+                                dir->i_ino, index, name, namelen);
+
+       BUG_ON(ret);
+
        ret = btrfs_commit_transaction(trans, root);
        if (ret)
                goto fail_commit;
@@ -163,7 +176,7 @@ printk("inserting root objectid %Lu\n", objectid);
        trans = btrfs_start_transaction(new_root, 1);
        BUG_ON(!trans);
 
-       ret = btrfs_create_subvol_root(new_root, dentry, trans, new_dirid,
+       ret = btrfs_create_subvol_root(trans, new_root, dentry, new_dirid,
                                       BTRFS_I(dir)->block_group);
        if (ret)
                goto fail;
@@ -175,7 +188,6 @@ fail:
                ret = err;
 fail_commit:
        btrfs_btree_balance_dirty(root, nr);
-printk("all done ret %d\n", ret);
        return ret;
 }
 
@@ -276,6 +288,58 @@ static noinline int btrfs_mksubvol(struct path *parent, char *name,
         * subvolume with specific mode bits.
         */
        if (snap_src) {
+               struct dentry *dir = dentry->d_parent;
+               struct dentry *test = dir->d_parent;
+               struct btrfs_path *path = btrfs_alloc_path();
+               int ret;
+               u64 test_oid;
+               u64 parent_oid = BTRFS_I(dir->d_inode)->root->root_key.objectid;
+
+               test_oid = snap_src->root_key.objectid;
+
+               ret = btrfs_find_root_ref(snap_src->fs_info->tree_root,
+                                         path, parent_oid, test_oid);
+               if (ret == 0)
+                       goto create;
+               btrfs_release_path(snap_src->fs_info->tree_root, path);
+
+               /* we need to make sure we aren't creating a directory loop
+                * by taking a snapshot of something that has our current
+                * subvol in its directory tree.  So, this loops through
+                * the dentries and checks the forward refs for each subvolume
+                * to see if is references the subvolume where we are
+                * placing this new snapshot.
+                */
+               while (1) {
+                       if (!test ||
+                           dir == snap_src->fs_info->sb->s_root ||
+                           test == snap_src->fs_info->sb->s_root ||
+                           test->d_inode->i_sb != snap_src->fs_info->sb) {
+                               break;
+                       }
+                       if (S_ISLNK(test->d_inode->i_mode)) {
+                               printk(KERN_INFO "Btrfs symlink in snapshot "
+                                      "path, failed\n");
+                               error = -EMLINK;
+                               btrfs_free_path(path);
+                               goto out_drop_write;
+                       }
+                       test_oid =
+                               BTRFS_I(test->d_inode)->root->root_key.objectid;
+                       ret = btrfs_find_root_ref(snap_src->fs_info->tree_root,
+                                 path, test_oid, parent_oid);
+                       if (ret == 0) {
+                               printk(KERN_INFO "Btrfs snapshot creation "
+                                      "failed, looping\n");
+                               error = -EMLINK;
+                               btrfs_free_path(path);
+                               goto out_drop_write;
+                       }
+                       btrfs_release_path(snap_src->fs_info->tree_root, path);
+                       test = test->d_parent;
+               }
+create:
+               btrfs_free_path(path);
                error = create_snapshot(snap_src, dentry, name, namelen);
        } else {
                error = create_subvol(BTRFS_I(parent->dentry->d_inode)->root,
@@ -295,7 +359,7 @@ out_unlock:
 }
 
 
-int btrfs_defrag_file(struct file *file)
+static int btrfs_defrag_file(struct file *file)
 {
        struct inode *inode = fdentry(file)->d_inode;
        struct btrfs_root *root = BTRFS_I(inode)->root;
@@ -394,6 +458,9 @@ static int btrfs_ioctl_resize(struct btrfs_root *root, void __user *arg)
        if (root->fs_info->sb->s_flags & MS_RDONLY)
                return -EROFS;
 
+       if (!capable(CAP_SYS_ADMIN))
+               return -EPERM;
+
        vol_args = kmalloc(sizeof(*vol_args), GFP_NOFS);
 
        if (!vol_args)
@@ -551,7 +618,8 @@ static noinline int btrfs_ioctl_snap_create(struct file *file,
 
                src_inode = src_file->f_path.dentry->d_inode;
                if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) {
-                       printk("btrfs: Snapshot src from another FS\n");
+                       printk(KERN_INFO "btrfs: Snapshot src from "
+                              "another FS\n");
                        ret = -EINVAL;
                        fput(src_file);
                        goto out;
@@ -579,22 +647,34 @@ static int btrfs_ioctl_defrag(struct file *file)
 
        switch (inode->i_mode & S_IFMT) {
        case S_IFDIR:
+               if (!capable(CAP_SYS_ADMIN)) {
+                       ret = -EPERM;
+                       goto out;
+               }
                btrfs_defrag_root(root, 0);
                btrfs_defrag_root(root->fs_info->extent_root, 0);
                break;
        case S_IFREG:
+               if (!(file->f_mode & FMODE_WRITE)) {
+                       ret = -EINVAL;
+                       goto out;
+               }
                btrfs_defrag_file(file);
                break;
        }
-
-       return 0;
+out:
+       mnt_drop_write(file->f_path.mnt);
+       return ret;
 }
 
-long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
+static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
 {
        struct btrfs_ioctl_vol_args *vol_args;
        int ret;
 
+       if (!capable(CAP_SYS_ADMIN))
+               return -EPERM;
+
        vol_args = kmalloc(sizeof(*vol_args), GFP_NOFS);
 
        if (!vol_args)
@@ -612,11 +692,14 @@ out:
        return ret;
 }
 
-long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg)
+static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg)
 {
        struct btrfs_ioctl_vol_args *vol_args;
        int ret;
 
+       if (!capable(CAP_SYS_ADMIN))
+               return -EPERM;
+
        if (root->fs_info->sb->s_flags & MS_RDONLY)
                return -EROFS;
 
@@ -637,8 +720,8 @@ out:
        return ret;
 }
 
-long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, u64 off,
-                      u64 olen, u64 destoff)
+static long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
+               u64 off, u64 olen, u64 destoff)
 {
        struct inode *inode = fdentry(file)->d_inode;
        struct btrfs_root *root = BTRFS_I(inode)->root;
@@ -666,13 +749,19 @@ long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, u64 off,
         *   they don't overlap)?
         */
 
+       /* the destination must be opened for writing */
+       if (!(file->f_mode & FMODE_WRITE))
+               return -EINVAL;
+
        ret = mnt_want_write(file->f_path.mnt);
        if (ret)
                return ret;
 
        src_file = fget(srcfd);
-       if (!src_file)
-               return -EBADF;
+       if (!src_file) {
+               ret = -EBADF;
+               goto out_drop_write;
+       }
        src = src_file->f_dentry->d_inode;
 
        ret = -EINVAL;
@@ -723,9 +812,6 @@ long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, u64 off,
            ((off + len) & (bs-1)))
                goto out_unlock;
 
-       printk("final src extent is %llu~%llu\n", off, len);
-       printk("final dst extent is %llu~%llu\n", destoff, len);
-
        /* do any pending delalloc/csum calc on src, one way or
           another, and lock file content */
        while (1) {
@@ -773,7 +859,7 @@ long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, u64 off,
                slot = path->slots[0];
 
                btrfs_item_key_to_cpu(leaf, &key, slot);
-               if (btrfs_key_type(&key) > BTRFS_CSUM_ITEM_KEY ||
+               if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
                    key.objectid != src->i_ino)
                        break;
 
@@ -796,10 +882,13 @@ long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, u64 off,
                        comp = btrfs_file_extent_compression(leaf, extent);
                        type = btrfs_file_extent_type(leaf, extent);
                        if (type == BTRFS_FILE_EXTENT_REG) {
-                               disko = btrfs_file_extent_disk_bytenr(leaf, extent);
-                               diskl = btrfs_file_extent_disk_num_bytes(leaf, extent);
+                               disko = btrfs_file_extent_disk_bytenr(leaf,
+                                                                     extent);
+                               diskl = btrfs_file_extent_disk_num_bytes(leaf,
+                                                                extent);
                                datao = btrfs_file_extent_offset(leaf, extent);
-                               datal = btrfs_file_extent_num_bytes(leaf, extent);
+                               datal = btrfs_file_extent_num_bytes(leaf,
+                                                                   extent);
                        } else if (type == BTRFS_FILE_EXTENT_INLINE) {
                                /* take upper bound, may be compressed */
                                datal = btrfs_file_extent_ram_bytes(leaf,
@@ -829,8 +918,6 @@ long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, u64 off,
 
                                extent = btrfs_item_ptr(leaf, slot,
                                                struct btrfs_file_extent_item);
-                               printk("  orig disk %llu~%llu data %llu~%llu\n",
-                                      disko, diskl, datao, datal);
 
                                if (off > key.offset) {
                                        datao += off - key.offset;
@@ -842,8 +929,6 @@ long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, u64 off,
                                /* disko == 0 means it's a hole */
                                if (!disko)
                                        datao = 0;
-                               printk(" final disk %llu~%llu data %llu~%llu\n",
-                                      disko, diskl, datao, datal);
 
                                btrfs_set_file_extent_offset(leaf, extent,
                                                             datao);
@@ -865,12 +950,11 @@ long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, u64 off,
                                        skip = off - key.offset;
                                        new_key.offset += skip;
                                }
+
                                if (key.offset + datal > off+len)
                                        trim = key.offset + datal - (off+len);
-                               printk("len %lld skip %lld trim %lld\n",
-                                      datal, skip, trim);
+
                                if (comp && (skip || trim)) {
-                                       printk("btrfs clone_range can't split compressed inline extents yet\n");
                                        ret = -EINVAL;
                                        goto out;
                                }
@@ -882,7 +966,8 @@ long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, u64 off,
                                        goto out;
 
                                if (skip) {
-                                       u32 start = btrfs_file_extent_calc_inline_size(0);
+                                       u32 start =
+                                         btrfs_file_extent_calc_inline_size(0);
                                        memmove(buf+start, buf+start+skip,
                                                datal);
                                }
@@ -898,57 +983,7 @@ long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, u64 off,
                        btrfs_mark_buffer_dirty(leaf);
                }
 
-               if (btrfs_key_type(&key) == BTRFS_CSUM_ITEM_KEY) {
-                       u32 size;
-                       struct btrfs_key new_key;
-                       u64 coverslen;
-                       int coff, clen;
-
-                       size = btrfs_item_size_nr(leaf, slot);
-                       coverslen = (size / BTRFS_CRC32_SIZE) <<
-                               root->fs_info->sb->s_blocksize_bits;
-                       printk("csums for %llu~%llu\n",
-                              key.offset, coverslen);
-                       if (key.offset + coverslen < off ||
-                           key.offset >= off+len)
-                               goto next;
-
-                       read_extent_buffer(leaf, buf,
-                                          btrfs_item_ptr_offset(leaf, slot),
-                                          size);
-                       btrfs_release_path(root, path);
-
-                       coff = 0;
-                       if (off > key.offset)
-                               coff = ((off - key.offset) >>
-                                       root->fs_info->sb->s_blocksize_bits) *
-                                       BTRFS_CRC32_SIZE;
-                       clen = size - coff;
-                       if (key.offset + coverslen > off+len)
-                               clen -= ((key.offset+coverslen-off-len) >>
-                                        root->fs_info->sb->s_blocksize_bits) *
-                                       BTRFS_CRC32_SIZE;
-                       printk(" will dup %d~%d of %d\n",
-                              coff, clen, size);
-
-                       memcpy(&new_key, &key, sizeof(new_key));
-                       new_key.objectid = inode->i_ino;
-                       new_key.offset = key.offset + destoff - off;
-
-                       ret = btrfs_insert_empty_item(trans, root, path,
-                                                     &new_key, clen);
-                       if (ret)
-                               goto out;
-
-                       leaf = path->nodes[0];
-                       slot = path->slots[0];
-                       write_extent_buffer(leaf, buf + coff,
-                                           btrfs_item_ptr_offset(leaf, slot),
-                                           clen);
-                       btrfs_mark_buffer_dirty(leaf);
-               }
-
-       next:
+next:
                btrfs_release_path(root, path);
                key.offset++;
        }
@@ -973,14 +1008,16 @@ out_unlock:
        btrfs_free_path(path);
 out_fput:
        fput(src_file);
+out_drop_write:
+       mnt_drop_write(file->f_path.mnt);
        return ret;
 }
 
-long btrfs_ioctl_clone_range(struct file *file, unsigned long argptr)
+static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
 {
        struct btrfs_ioctl_clone_range_args args;
 
-       if (copy_from_user(&args, (void *)argptr, sizeof(args)))
+       if (copy_from_user(&args, argp, sizeof(args)))
                return -EFAULT;
        return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
                                 args.src_length, args.dest_offset);
@@ -992,7 +1029,7 @@ long btrfs_ioctl_clone_range(struct file *file, unsigned long argptr)
  * basically own the machine, and have a very in depth understanding
  * of all the possible deadlocks and enospc problems.
  */
-long btrfs_ioctl_trans_start(struct file *file)
+static long btrfs_ioctl_trans_start(struct file *file)
 {
        struct inode *inode = fdentry(file)->d_inode;
        struct btrfs_root *root = BTRFS_I(inode)->root;
@@ -1050,6 +1087,8 @@ long btrfs_ioctl_trans_end(struct file *file)
        root->fs_info->open_ioctl_trans--;
        mutex_unlock(&root->fs_info->trans_mutex);
 
+       mnt_drop_write(file->f_path.mnt);
+
 out:
        return ret;
 }
@@ -1058,32 +1097,32 @@ long btrfs_ioctl(struct file *file, unsigned int
                cmd, unsigned long arg)
 {
        struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
+       void __user *argp = (void __user *)arg;
 
        switch (cmd) {
        case BTRFS_IOC_SNAP_CREATE:
-               return btrfs_ioctl_snap_create(file, (void __user *)arg, 0);
+               return btrfs_ioctl_snap_create(file, argp, 0);
        case BTRFS_IOC_SUBVOL_CREATE:
-               return btrfs_ioctl_snap_create(file, (void __user *)arg, 1);
+               return btrfs_ioctl_snap_create(file, argp, 1);
        case BTRFS_IOC_DEFRAG:
                return btrfs_ioctl_defrag(file);
        case BTRFS_IOC_RESIZE:
-               return btrfs_ioctl_resize(root, (void __user *)arg);
+               return btrfs_ioctl_resize(root, argp);
        case BTRFS_IOC_ADD_DEV:
-               return btrfs_ioctl_add_dev(root, (void __user *)arg);
+               return btrfs_ioctl_add_dev(root, argp);
        case BTRFS_IOC_RM_DEV:
-               return btrfs_ioctl_rm_dev(root, (void __user *)arg);
+               return btrfs_ioctl_rm_dev(root, argp);
        case BTRFS_IOC_BALANCE:
                return btrfs_balance(root->fs_info->dev_root);
        case BTRFS_IOC_CLONE:
                return btrfs_ioctl_clone(file, arg, 0, 0, 0);
        case BTRFS_IOC_CLONE_RANGE:
-               return btrfs_ioctl_clone_range(file, arg);
+               return btrfs_ioctl_clone_range(file, argp);
        case BTRFS_IOC_TRANS_START:
                return btrfs_ioctl_trans_start(file);
        case BTRFS_IOC_TRANS_END:
                return btrfs_ioctl_trans_end(file);
        case BTRFS_IOC_SYNC:
-               btrfs_start_delalloc_inodes(root);
                btrfs_sync_fs(file->f_dentry->d_sb, 1);
                return 0;
        }