1 files changed, 194 insertions, 58 deletions

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index f87552a1d7ea..5fdb2abc4fa7 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -147,6 +147,9 @@ static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
         unsigned int flags, oldflags;
         int ret;
 
+        if (btrfs_root_readonly(root))
+                return -EROFS;
+
         if (copy_from_user(&flags, arg, sizeof(flags)))
                 return -EFAULT;
 
@@ -200,7 +203,7 @@ static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
 
 
         trans = btrfs_join_transaction(root, 1);
-        BUG_ON(!trans);
+        BUG_ON(IS_ERR(trans));
 
         ret = btrfs_update_inode(trans, root, inode);
         BUG_ON(ret);
@@ -360,7 +363,8 @@ fail:
 }
 
 static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
-                           char *name, int namelen, u64 *async_transid)
+                           char *name, int namelen, u64 *async_transid,
+                           bool readonly)
 {
         struct inode *inode;
         struct dentry *parent;
@@ -378,6 +382,7 @@ static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
         btrfs_init_block_rsv(&pending_snapshot->block_rsv);
         pending_snapshot->dentry = dentry;
         pending_snapshot->root = root;
+        pending_snapshot->readonly = readonly;
 
         trans = btrfs_start_transaction(root->fs_info->extent_root, 5);
         if (IS_ERR(trans)) {
@@ -509,7 +514,7 @@ static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
 static noinline int btrfs_mksubvol(struct path *parent,
                                    char *name, int namelen,
                                    struct btrfs_root *snap_src,
-                                   u64 *async_transid)
+                                   u64 *async_transid, bool readonly)
 {
         struct inode *dir  = parent->dentry->d_inode;
         struct dentry *dentry;
@@ -541,7 +546,7 @@ static noinline int btrfs_mksubvol(struct path *parent,
 
         if (snap_src) {
                 error = create_snapshot(snap_src, dentry,
-                                        name, namelen, async_transid);
+                                        name, namelen, async_transid, readonly);
         } else {
                 error = create_subvol(BTRFS_I(dir)->root, dentry,
                                       name, namelen, async_transid);
@@ -638,9 +643,11 @@ static int btrfs_defrag_file(struct file *file,
         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
         struct btrfs_ordered_extent *ordered;
         struct page *page;
+        struct btrfs_super_block *disk_super;
         unsigned long last_index;
         unsigned long ra_pages = root->fs_info->bdi.ra_pages;
         unsigned long total_read = 0;
+        u64 features;
         u64 page_start;
         u64 page_end;
         u64 last_len = 0;
@@ -648,6 +655,14 @@ static int btrfs_defrag_file(struct file *file,
         u64 defrag_end = 0;
         unsigned long i;
         int ret;
+        int compress_type = BTRFS_COMPRESS_ZLIB;
+
+        if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
+                if (range->compress_type > BTRFS_COMPRESS_TYPES)
+                        return -EINVAL;
+                if (range->compress_type)
+                        compress_type = range->compress_type;
+        }
 
         if (inode->i_size == 0)
                 return 0;
@@ -683,7 +698,7 @@ static int btrfs_defrag_file(struct file *file,
                 total_read++;
                 mutex_lock(&inode->i_mutex);
                 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
-                        BTRFS_I(inode)->force_compress = 1;
+                        BTRFS_I(inode)->force_compress = compress_type;
 
                 ret  = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
                 if (ret)
@@ -781,10 +796,17 @@ loop_unlock:
                 atomic_dec(&root->fs_info->async_submit_draining);
 
                 mutex_lock(&inode->i_mutex);
-                BTRFS_I(inode)->force_compress = 0;
+                BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
                 mutex_unlock(&inode->i_mutex);
         }
 
+        disk_super = &root->fs_info->super_copy;
+        features = btrfs_super_incompat_flags(disk_super);
+        if (range->compress_type == BTRFS_COMPRESS_LZO) {
+                features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
+                btrfs_set_super_incompat_flags(disk_super, features);
+        }
+
         return 0;
 
 err_reservations:
@@ -885,6 +907,10 @@ static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
 
         if (new_size > old_size) {
                 trans = btrfs_start_transaction(root, 0);
+                if (IS_ERR(trans)) {
+                        ret = PTR_ERR(trans);
+                        goto out_unlock;
+                }
                 ret = btrfs_grow_device(trans, device, new_size);
                 btrfs_commit_transaction(trans, root);
         } else {
@@ -901,7 +927,8 @@ static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
                                                     char *name,
                                                     unsigned long fd,
                                                     int subvol,
-                                                    u64 *transid)
+                                                    u64 *transid,
+                                                    bool readonly)
 {
         struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
         struct file *src_file;
@@ -919,7 +946,7 @@ static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
 
         if (subvol) {
                 ret = btrfs_mksubvol(&file->f_path, name, namelen,
-                                     NULL, transid);
+                                     NULL, transid, readonly);
         } else {
                 struct inode *src_inode;
                 src_file = fget(fd);
@@ -938,7 +965,7 @@ static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
                 }
                 ret = btrfs_mksubvol(&file->f_path, name, namelen,
                                      BTRFS_I(src_inode)->root,
-                                     transid);
+                                     transid, readonly);
                 fput(src_file);
         }
 out:
@@ -946,58 +973,142 @@ out:
 }
 
 static noinline int btrfs_ioctl_snap_create(struct file *file,
-                                            void __user *arg, int subvol,
-                                            int v2)
+                                            void __user *arg, int subvol)
 {
-        struct btrfs_ioctl_vol_args *vol_args = NULL;
-        struct btrfs_ioctl_vol_args_v2 *vol_args_v2 = NULL;
-        char *name;
-        u64 fd;
+        struct btrfs_ioctl_vol_args *vol_args;
         int ret;
 
-        if (v2) {
-                u64 transid = 0;
-                u64 *ptr = NULL;
+        vol_args = memdup_user(arg, sizeof(*vol_args));
+        if (IS_ERR(vol_args))
+                return PTR_ERR(vol_args);
+        vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
 
-                vol_args_v2 = memdup_user(arg, sizeof(*vol_args_v2));
-                if (IS_ERR(vol_args_v2))
-                        return PTR_ERR(vol_args_v2);
+        ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
+                                              vol_args->fd, subvol,
+                                              NULL, false);
 
-                if (vol_args_v2->flags & ~BTRFS_SUBVOL_CREATE_ASYNC) {
-                        ret = -EINVAL;
-                        goto out;
-                }
-
-                name = vol_args_v2->name;
-                fd = vol_args_v2->fd;
-                vol_args_v2->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
+        kfree(vol_args);
+        return ret;
+}
 
-                if (vol_args_v2->flags & BTRFS_SUBVOL_CREATE_ASYNC)
-                        ptr = &transid;
+static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
+                                               void __user *arg, int subvol)
+{
+        struct btrfs_ioctl_vol_args_v2 *vol_args;
+        int ret;
+        u64 transid = 0;
+        u64 *ptr = NULL;
+        bool readonly = false;
 
-                ret = btrfs_ioctl_snap_create_transid(file, name, fd,
-                                                      subvol, ptr);
+        vol_args = memdup_user(arg, sizeof(*vol_args));
+        if (IS_ERR(vol_args))
+                return PTR_ERR(vol_args);
+        vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
 
-                if (ret == 0 && ptr &&
-                    copy_to_user(arg +
-                                 offsetof(struct btrfs_ioctl_vol_args_v2,
-                                          transid), ptr, sizeof(*ptr)))
-                        ret = -EFAULT;
-        } else {
-                vol_args = memdup_user(arg, sizeof(*vol_args));
-                if (IS_ERR(vol_args))
-                        return PTR_ERR(vol_args);
-                name = vol_args->name;
-                fd = vol_args->fd;
-                vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
-
-                ret = btrfs_ioctl_snap_create_transid(file, name, fd,
-                                                      subvol, NULL);
+        if (vol_args->flags &
+            ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY)) {
+                ret = -EOPNOTSUPP;
+                goto out;
         }
+
+        if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
+                ptr = &transid;
+        if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
+                readonly = true;
+
+        ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
+                                              vol_args->fd, subvol,
+                                              ptr, readonly);
+
+        if (ret == 0 && ptr &&
+            copy_to_user(arg +
+                         offsetof(struct btrfs_ioctl_vol_args_v2,
+                                  transid), ptr, sizeof(*ptr)))
+                ret = -EFAULT;
 out:
         kfree(vol_args);
-        kfree(vol_args_v2);
+        return ret;
+}
+
+static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
+                                                void __user *arg)
+{
+        struct inode *inode = fdentry(file)->d_inode;
+        struct btrfs_root *root = BTRFS_I(inode)->root;
+        int ret = 0;
+        u64 flags = 0;
+
+        if (inode->i_ino != BTRFS_FIRST_FREE_OBJECTID)
+                return -EINVAL;
+
+        down_read(&root->fs_info->subvol_sem);
+        if (btrfs_root_readonly(root))
+                flags |= BTRFS_SUBVOL_RDONLY;
+        up_read(&root->fs_info->subvol_sem);
+
+        if (copy_to_user(arg, &flags, sizeof(flags)))
+                ret = -EFAULT;
+
+        return ret;
+}
+
+static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
+                                              void __user *arg)
+{
+        struct inode *inode = fdentry(file)->d_inode;
+        struct btrfs_root *root = BTRFS_I(inode)->root;
+        struct btrfs_trans_handle *trans;
+        u64 root_flags;
+        u64 flags;
+        int ret = 0;
+
+        if (root->fs_info->sb->s_flags & MS_RDONLY)
+                return -EROFS;
+
+        if (inode->i_ino != BTRFS_FIRST_FREE_OBJECTID)
+                return -EINVAL;
+
+        if (copy_from_user(&flags, arg, sizeof(flags)))
+                return -EFAULT;
+
+        if (flags & BTRFS_SUBVOL_CREATE_ASYNC)
+                return -EINVAL;
+
+        if (flags & ~BTRFS_SUBVOL_RDONLY)
+                return -EOPNOTSUPP;
+
+        if (!is_owner_or_cap(inode))
+                return -EACCES;
+
+        down_write(&root->fs_info->subvol_sem);
+
+        /* nothing to do */
+        if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
+                goto out;
 
+        root_flags = btrfs_root_flags(&root->root_item);
+        if (flags & BTRFS_SUBVOL_RDONLY)
+                btrfs_set_root_flags(&root->root_item,
+                                     root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
+        else
+                btrfs_set_root_flags(&root->root_item,
+                                     root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
+
+        trans = btrfs_start_transaction(root, 1);
+        if (IS_ERR(trans)) {
+                ret = PTR_ERR(trans);
+                goto out_reset;
+        }
+
+        ret = btrfs_update_root(trans, root->fs_info->tree_root,
+                                &root->root_key, &root->root_item);
+
+        btrfs_commit_transaction(trans, root);
+out_reset:
+        if (ret)
+                btrfs_set_root_flags(&root->root_item, root_flags);
+out:
+        up_write(&root->fs_info->subvol_sem);
         return ret;
 }
 
@@ -1509,6 +1620,9 @@ static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
         struct btrfs_ioctl_defrag_range_args *range;
         int ret;
 
+        if (btrfs_root_readonly(root))
+                return -EROFS;
+
         ret = mnt_want_write(file->f_path.mnt);
         if (ret)
                 return ret;
@@ -1637,6 +1751,9 @@ static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
         if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
                 return -EINVAL;
 
+        if (btrfs_root_readonly(root))
+                return -EROFS;
+
         ret = mnt_want_write(file->f_path.mnt);
         if (ret)
                 return ret;
@@ -1788,7 +1905,10 @@ static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
 
                         memcpy(&new_key, &key, sizeof(new_key));
                         new_key.objectid = inode->i_ino;
-                        new_key.offset = key.offset + destoff - off;
+                        if (off <= key.offset)
+                                new_key.offset = key.offset + destoff - off;
+                        else
+                                new_key.offset = destoff;
 
                         trans = btrfs_start_transaction(root, 1);
                         if (IS_ERR(trans)) {
@@ -1958,6 +2078,10 @@ static long btrfs_ioctl_trans_start(struct file *file)
         if (file->private_data)
                 goto out;
 
+        ret = -EROFS;
+        if (btrfs_root_readonly(root))
+                goto out;
+
         ret = mnt_want_write(file->f_path.mnt);
         if (ret)
                 goto out;
@@ -1968,7 +2092,7 @@ static long btrfs_ioctl_trans_start(struct file *file)
 
         ret = -ENOMEM;
         trans = btrfs_start_ioctl_transaction(root, 0);
-        if (!trans)
+        if (IS_ERR(trans))
                 goto out_drop;
 
         file->private_data = trans;
@@ -2024,9 +2148,9 @@ static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
         path->leave_spinning = 1;
 
         trans = btrfs_start_transaction(root, 1);
-        if (!trans) {
+        if (IS_ERR(trans)) {
                 btrfs_free_path(path);
-                return -ENOMEM;
+                return PTR_ERR(trans);
         }
 
         dir_id = btrfs_super_root_dir(&root->fs_info->super_copy);
@@ -2087,7 +2211,7 @@ long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
         int num_types = 4;
         int alloc_size;
         int ret = 0;
-        int slot_count = 0;
+        u64 slot_count = 0;
         int i, c;
 
         if (copy_from_user(&space_args,
@@ -2126,7 +2250,7 @@ long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
                 goto out;
         }
 
-        slot_count = min_t(int, space_args.space_slots, slot_count);
+        slot_count = min_t(u64, space_args.space_slots, slot_count);
 
         alloc_size = sizeof(*dest) * slot_count;
 
@@ -2146,6 +2270,9 @@ long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
         for (i = 0; i < num_types; i++) {
                 struct btrfs_space_info *tmp;
 
+                if (!slot_count)
+                        break;
+
                 info = NULL;
                 rcu_read_lock();
                 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
@@ -2167,7 +2294,10 @@ long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
                                 memcpy(dest, &space, sizeof(space));
                                 dest++;
                                 space_args.total_spaces++;
+                                slot_count--;
                         }
+                        if (!slot_count)
+                                break;
                 }
                 up_read(&info->groups_sem);
         }
@@ -2220,6 +2350,8 @@ static noinline long btrfs_ioctl_start_sync(struct file *file, void __user *argp
         u64 transid;
 
         trans = btrfs_start_transaction(root, 0);
+        if (IS_ERR(trans))
+                return PTR_ERR(trans);
         transid = trans->transid;
         btrfs_commit_transaction_async(trans, root, 0);
 
@@ -2257,13 +2389,17 @@ long btrfs_ioctl(struct file *file, unsigned int
         case FS_IOC_GETVERSION:
                 return btrfs_ioctl_getversion(file, argp);
         case BTRFS_IOC_SNAP_CREATE:
-                return btrfs_ioctl_snap_create(file, argp, 0, 0);
+                return btrfs_ioctl_snap_create(file, argp, 0);
         case BTRFS_IOC_SNAP_CREATE_V2:
-                return btrfs_ioctl_snap_create(file, argp, 0, 1);
+                return btrfs_ioctl_snap_create_v2(file, argp, 0);
         case BTRFS_IOC_SUBVOL_CREATE:
-                return btrfs_ioctl_snap_create(file, argp, 1, 0);
+                return btrfs_ioctl_snap_create(file, argp, 1);
         case BTRFS_IOC_SNAP_DESTROY:
                 return btrfs_ioctl_snap_destroy(file, argp);
+        case BTRFS_IOC_SUBVOL_GETFLAGS:
+                return btrfs_ioctl_subvol_getflags(file, argp);
+        case BTRFS_IOC_SUBVOL_SETFLAGS:
+                return btrfs_ioctl_subvol_setflags(file, argp);
         case BTRFS_IOC_DEFAULT_SUBVOL:
                 return btrfs_ioctl_default_subvol(file, argp);
         case BTRFS_IOC_DEFRAG: