Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
  Btrfs: set i_size properly when fallocating and we already
  btrfs: unlock on error in btrfs_file_llseek()
  btrfs: btrfs_permission's RO check shouldn't apply to device nodes
  Btrfs: truncate pages from clone ioctl target range
  Btrfs: fix uninitialized sync_pending
  Btrfs: fix wrong free space information
  btrfs: memory leak in btrfs_add_inode_defrag()
  Btrfs: use plain page_address() in header fields setget functions
  Btrfs: forced readonly when btrfs_drop_snapshot() fails
  Btrfs: check if there is enough space for balancing smarter
  Btrfs: fix a bug of balance on full multi-disk partitions
  Btrfs: fix an oops of log replay
  Btrfs: detect wether a device supports discard
  Btrfs: force unplugs when switching from high to regular priority bios

9 files changed, 183 insertions, 43 deletions

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 0469263e327e..03912c5c6f49 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1415,17 +1415,15 @@ void btrfs_set_##name(struct extent_buffer *eb, type *s, u##bits val);
 #define BTRFS_SETGET_HEADER_FUNCS(name, type, member, bits)             \
 static inline u##bits btrfs_##name(struct extent_buffer *eb)            \
 {                                                                       \
-        type *p = kmap_atomic(eb->first_page, KM_USER0);                \
+        type *p = page_address(eb->first_page);                         \
         u##bits res = le##bits##_to_cpu(p->member);                     \
-        kunmap_atomic(p, KM_USER0);                                     \
         return res;                                                     \
 }                                                                       \
 static inline void btrfs_set_##name(struct extent_buffer *eb,           \
                                     u##bits val)                        \
 {                                                                       \
-        type *p = kmap_atomic(eb->first_page, KM_USER0);                \
+        type *p = page_address(eb->first_page);                         \
         p->member = cpu_to_le##bits(val);                               \
-        kunmap_atomic(p, KM_USER0);                                     \
 }
 
 #define BTRFS_SETGET_STACK_FUNCS(name, type, member, bits)              \
@@ -2367,8 +2365,8 @@ static inline int btrfs_insert_empty_item(struct btrfs_trans_handle *trans,
 int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path);
 int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path);
 int btrfs_leaf_free_space(struct btrfs_root *root, struct extent_buffer *leaf);
-int btrfs_drop_snapshot(struct btrfs_root *root,
-                        struct btrfs_block_rsv *block_rsv, int update_ref);
+void btrfs_drop_snapshot(struct btrfs_root *root,
+                         struct btrfs_block_rsv *block_rsv, int update_ref);
 int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
                         struct btrfs_root *root,
                         struct extent_buffer *node,
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 66bac226944e..80d6148f60ac 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -1782,6 +1782,9 @@ static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
 
 
                 for (i = 0; i < multi->num_stripes; i++, stripe++) {
+                        if (!stripe->dev->can_discard)
+                                continue;
+
                         ret = btrfs_issue_discard(stripe->dev->bdev,
                                                   stripe->physical,
                                                   stripe->length);
@@ -1789,11 +1792,16 @@ static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
                                 discarded_bytes += stripe->length;
                         else if (ret != -EOPNOTSUPP)
                                 break;
+
+                        /*
+                         * Just in case we get back EOPNOTSUPP for some reason,
+                         * just ignore the return value so we don't screw up
+                         * people calling discard_extent.
+                         */
+                        ret = 0;
                 }
                 kfree(multi);
         }
-        if (discarded_bytes && ret == -EOPNOTSUPP)
-                ret = 0;
 
         if (actual_bytes)
                 *actual_bytes = discarded_bytes;
@@ -6269,8 +6277,8 @@ static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
  * also make sure backrefs for the shared block and all lower level
  * blocks are properly updated.
  */
-int btrfs_drop_snapshot(struct btrfs_root *root,
-                        struct btrfs_block_rsv *block_rsv, int update_ref)
+void btrfs_drop_snapshot(struct btrfs_root *root,
+                         struct btrfs_block_rsv *block_rsv, int update_ref)
 {
         struct btrfs_path *path;
         struct btrfs_trans_handle *trans;
@@ -6283,13 +6291,16 @@ int btrfs_drop_snapshot(struct btrfs_root *root,
         int level;
 
         path = btrfs_alloc_path();
-        if (!path)
-                return -ENOMEM;
+        if (!path) {
+                err = -ENOMEM;
+                goto out;
+        }
 
         wc = kzalloc(sizeof(*wc), GFP_NOFS);
         if (!wc) {
                 btrfs_free_path(path);
-                return -ENOMEM;
+                err = -ENOMEM;
+                goto out;
         }
 
         trans = btrfs_start_transaction(tree_root, 0);
@@ -6318,7 +6329,7 @@ int btrfs_drop_snapshot(struct btrfs_root *root,
                 path->lowest_level = 0;
                 if (ret < 0) {
                         err = ret;
-                        goto out;
+                        goto out_free;
                 }
                 WARN_ON(ret > 0);
 
@@ -6425,11 +6436,14 @@ int btrfs_drop_snapshot(struct btrfs_root *root,
                 free_extent_buffer(root->commit_root);
                 kfree(root);
         }
-out:
+out_free:
         btrfs_end_transaction_throttle(trans, tree_root);
         kfree(wc);
         btrfs_free_path(path);
-        return err;
+out:
+        if (err)
+                btrfs_std_error(root->fs_info, err);
+        return;
 }
 
 /*
@@ -6720,6 +6734,10 @@ int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
         struct btrfs_space_info *space_info;
         struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
         struct btrfs_device *device;
+        u64 min_free;
+        int index;
+        int dev_nr = 0;
+        int dev_min = 1;
         int full = 0;
         int ret = 0;
 
@@ -6729,8 +6747,10 @@ int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
         if (!block_group)
                 return -1;
 
+        min_free = btrfs_block_group_used(&block_group->item);
+
         /* no bytes used, we're good */
-        if (!btrfs_block_group_used(&block_group->item))
+        if (!min_free)
                 goto out;
 
         space_info = block_group->space_info;
@@ -6746,10 +6766,9 @@ int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
          * all of the extents from this block group.  If we can, we're good
          */
         if ((space_info->total_bytes != block_group->key.offset) &&
-           (space_info->bytes_used + space_info->bytes_reserved +
-            space_info->bytes_pinned + space_info->bytes_readonly +
-            btrfs_block_group_used(&block_group->item) <
-            space_info->total_bytes)) {
+            (space_info->bytes_used + space_info->bytes_reserved +
+             space_info->bytes_pinned + space_info->bytes_readonly +
+             min_free < space_info->total_bytes)) {
                 spin_unlock(&space_info->lock);
                 goto out;
         }
@@ -6766,9 +6785,29 @@ int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
         if (full)
                 goto out;
 
+        /*
+         * index:
+         *      0: raid10
+         *      1: raid1
+         *      2: dup
+         *      3: raid0
+         *      4: single
+         */
+        index = get_block_group_index(block_group);
+        if (index == 0) {
+                dev_min = 4;
+                min_free /= 2;
+        } else if (index == 1) {
+                dev_min = 2;
+        } else if (index == 2) {
+                min_free *= 2;
+        } else if (index == 3) {
+                dev_min = fs_devices->rw_devices;
+                min_free /= dev_min;
+        }
+
         mutex_lock(&root->fs_info->chunk_mutex);
         list_for_each_entry(device, &fs_devices->alloc_list, dev_alloc_list) {
-                u64 min_free = btrfs_block_group_used(&block_group->item);
                 u64 dev_offset;
 
                 /*
@@ -6779,7 +6818,11 @@ int btrfs_can_relocate(struct btrfs_root *root, u64 bytenr)
                         ret = find_free_dev_extent(NULL, device, min_free,
                                                    &dev_offset, NULL);
                         if (!ret)
+                                dev_nr++;
+
+                        if (dev_nr >= dev_min)
                                 break;
+
                         ret = -1;
                 }
         }
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 658d66959abe..e7872e485f13 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -150,6 +150,8 @@ int btrfs_add_inode_defrag(struct btrfs_trans_handle *trans,
         spin_lock(&root->fs_info->defrag_inodes_lock);
         if (!BTRFS_I(inode)->in_defrag)
                 __btrfs_add_inode_defrag(inode, defrag);
+        else
+                kfree(defrag);
         spin_unlock(&root->fs_info->defrag_inodes_lock);
         return 0;
 }
@@ -1638,11 +1640,15 @@ static long btrfs_fallocate(struct file *file, int mode,
 
         cur_offset = alloc_start;
         while (1) {
+                u64 actual_end;
+
                 em = btrfs_get_extent(inode, NULL, 0, cur_offset,
                                       alloc_end - cur_offset, 0);
                 BUG_ON(IS_ERR_OR_NULL(em));
                 last_byte = min(extent_map_end(em), alloc_end);
+                actual_end = min_t(u64, extent_map_end(em), offset + len);
                 last_byte = (last_byte + mask) & ~mask;
+
                 if (em->block_start == EXTENT_MAP_HOLE ||
                     (cur_offset >= inode->i_size &&
                      !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) {
@@ -1655,6 +1661,16 @@ static long btrfs_fallocate(struct file *file, int mode,
                                 free_extent_map(em);
                                 break;
                         }
+                } else if (actual_end > inode->i_size &&
+                           !(mode & FALLOC_FL_KEEP_SIZE)) {
+                        /*
+                         * We didn't need to allocate any more space, but we
+                         * still extended the size of the file so we need to
+                         * update i_size.
+                         */
+                        inode->i_ctime = CURRENT_TIME;
+                        i_size_write(inode, actual_end);
+                        btrfs_ordered_update_i_size(inode, actual_end, NULL);
                 }
                 free_extent_map(em);
 
@@ -1804,10 +1820,14 @@ static loff_t btrfs_file_llseek(struct file *file, loff_t offset, int origin)
                 }
         }
 
-        if (offset < 0 && !(file->f_mode & FMODE_UNSIGNED_OFFSET))
-                return -EINVAL;
-        if (offset > inode->i_sb->s_maxbytes)
-                return -EINVAL;
+        if (offset < 0 && !(file->f_mode & FMODE_UNSIGNED_OFFSET)) {
+                ret = -EINVAL;
+                goto out;
+        }
+        if (offset > inode->i_sb->s_maxbytes) {
+                ret = -EINVAL;
+                goto out;
+        }
 
         /* Special lock needed here? */
         if (offset != file->f_pos) {
diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index 6377713f639c..6a265b9f85f2 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -1168,9 +1168,9 @@ static void recalculate_thresholds(struct btrfs_free_space_ctl *ctl)
                 div64_u64(extent_bytes, (sizeof(struct btrfs_free_space)));
 }
 
-static void bitmap_clear_bits(struct btrfs_free_space_ctl *ctl,
-                              struct btrfs_free_space *info, u64 offset,
-                              u64 bytes)
+static inline void __bitmap_clear_bits(struct btrfs_free_space_ctl *ctl,
+                                       struct btrfs_free_space *info,
+                                       u64 offset, u64 bytes)
 {
         unsigned long start, count;
 
@@ -1181,6 +1181,13 @@ static void bitmap_clear_bits(struct btrfs_free_space_ctl *ctl,
         bitmap_clear(info->bitmap, start, count);
 
         info->bytes -= bytes;
+}
+
+static void bitmap_clear_bits(struct btrfs_free_space_ctl *ctl,
+                              struct btrfs_free_space *info, u64 offset,
+                              u64 bytes)
+{
+        __bitmap_clear_bits(ctl, info, offset, bytes);
         ctl->free_space -= bytes;
 }
 
@@ -1984,7 +1991,7 @@ static u64 btrfs_alloc_from_bitmap(struct btrfs_block_group_cache *block_group,
                 return 0;
 
         ret = search_start;
-        bitmap_clear_bits(ctl, entry, ret, bytes);
+        __bitmap_clear_bits(ctl, entry, ret, bytes);
 
         return ret;
 }
@@ -2039,7 +2046,6 @@ u64 btrfs_alloc_from_cluster(struct btrfs_block_group_cache *block_group,
                                 continue;
                         }
                 } else {
-
                         ret = entry->offset;
 
                         entry->offset += bytes;
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 15fceefbca0a..0ccc7438ad34 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -7354,11 +7354,15 @@ static int btrfs_set_page_dirty(struct page *page)
 static int btrfs_permission(struct inode *inode, int mask)
 {
         struct btrfs_root *root = BTRFS_I(inode)->root;
+        umode_t mode = inode->i_mode;
 
-        if (btrfs_root_readonly(root) && (mask & MAY_WRITE))
-                return -EROFS;
-        if ((BTRFS_I(inode)->flags & BTRFS_INODE_READONLY) && (mask & MAY_WRITE))
-                return -EACCES;
+        if (mask & MAY_WRITE &&
+            (S_ISREG(mode) || S_ISDIR(mode) || S_ISLNK(mode))) {
+                if (btrfs_root_readonly(root))
+                        return -EROFS;
+                if (BTRFS_I(inode)->flags & BTRFS_INODE_READONLY)
+                        return -EACCES;
+        }
         return generic_permission(inode, mask);
 }
 
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 7cf013349941..970977aab224 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -2236,6 +2236,10 @@ static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
                 btrfs_wait_ordered_range(src, off, len);
         }
 
+        /* truncate page cache pages from target inode range */
+        truncate_inode_pages_range(&inode->i_data, off,
+                                   ALIGN(off + len, PAGE_CACHE_SIZE) - 1);
+
         /* clone data */
         key.objectid = btrfs_ino(src);
         key.type = BTRFS_EXTENT_DATA_KEY;
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index babee65f8eda..786639fca067 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -799,14 +799,15 @@ static noinline int add_inode_ref(struct btrfs_trans_handle *trans,
                                   struct extent_buffer *eb, int slot,
                                   struct btrfs_key *key)
 {
-        struct inode *dir;
-        int ret;
         struct btrfs_inode_ref *ref;
+        struct btrfs_dir_item *di;
+        struct inode *dir;
         struct inode *inode;
-        char *name;
-        int namelen;
         unsigned long ref_ptr;
         unsigned long ref_end;
+        char *name;
+        int namelen;
+        int ret;
         int search_done = 0;
 
         /*
@@ -909,6 +910,25 @@ again:
         }
         btrfs_release_path(path);
 
+        /* look for a conflicting sequence number */
+        di = btrfs_lookup_dir_index_item(trans, root, path, btrfs_ino(dir),
+                                         btrfs_inode_ref_index(eb, ref),
+                                         name, namelen, 0);
+        if (di && !IS_ERR(di)) {
+                ret = drop_one_dir_item(trans, root, path, dir, di);
+                BUG_ON(ret);
+        }
+        btrfs_release_path(path);
+
+        /* look for a conflicing name */
+        di = btrfs_lookup_dir_item(trans, root, path, btrfs_ino(dir),
+                                   name, namelen, 0);
+        if (di && !IS_ERR(di)) {
+                ret = drop_one_dir_item(trans, root, path, dir, di);
+                BUG_ON(ret);
+        }
+        btrfs_release_path(path);
+
 insert:
         /* insert our name */
         ret = btrfs_add_link(trans, dir, inode, name, namelen, 0,
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 53875ae73ad4..f2a4cc79da61 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -142,6 +142,7 @@ static noinline int run_scheduled_bios(struct btrfs_device *device)
         unsigned long limit;
         unsigned long last_waited = 0;
         int force_reg = 0;
+        int sync_pending = 0;
         struct blk_plug plug;
 
         /*
@@ -229,6 +230,22 @@ loop_lock:
 
                 BUG_ON(atomic_read(&cur->bi_cnt) == 0);
 
+                /*
+                 * if we're doing the sync list, record that our
+                 * plug has some sync requests on it
+                 *
+                 * If we're doing the regular list and there are
+                 * sync requests sitting around, unplug before
+                 * we add more
+                 */
+                if (pending_bios == &device->pending_sync_bios) {
+                        sync_pending = 1;
+                } else if (sync_pending) {
+                        blk_finish_plug(&plug);
+                        blk_start_plug(&plug);
+                        sync_pending = 0;
+                }
+
                 submit_bio(cur->bi_rw, cur);
                 num_run++;
                 batch_run++;
@@ -500,6 +517,9 @@ static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
                         fs_devices->rw_devices--;
                 }
 
+                if (device->can_discard)
+                        fs_devices->num_can_discard--;
+
                 new_device = kmalloc(sizeof(*new_device), GFP_NOFS);
                 BUG_ON(!new_device);
                 memcpy(new_device, device, sizeof(*new_device));
@@ -508,6 +528,7 @@ static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
                 new_device->bdev = NULL;
                 new_device->writeable = 0;
                 new_device->in_fs_metadata = 0;
+                new_device->can_discard = 0;
                 list_replace_rcu(&device->dev_list, &new_device->dev_list);
 
                 call_rcu(&device->rcu, free_device);
@@ -547,6 +568,7 @@ int btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
 static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
                                 fmode_t flags, void *holder)
 {
+        struct request_queue *q;
         struct block_device *bdev;
         struct list_head *head = &fs_devices->devices;
         struct btrfs_device *device;
@@ -603,6 +625,12 @@ static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
                         seeding = 0;
                 }
 
+                q = bdev_get_queue(bdev);
+                if (blk_queue_discard(q)) {
+                        device->can_discard = 1;
+                        fs_devices->num_can_discard++;
+                }
+
                 device->bdev = bdev;
                 device->in_fs_metadata = 0;
                 device->mode = flags;
@@ -835,6 +863,7 @@ int find_free_dev_extent(struct btrfs_trans_handle *trans,
 
         max_hole_start = search_start;
         max_hole_size = 0;
+        hole_size = 0;
 
         if (search_start >= search_end) {
                 ret = -ENOSPC;
@@ -917,7 +946,14 @@ next:
                 cond_resched();
         }
 
-        hole_size = search_end- search_start;
+        /*
+         * At this point, search_start should be the end of
+         * allocated dev extents, and when shrinking the device,
+         * search_end may be smaller than search_start.
+         */
+        if (search_end > search_start)
+                hole_size = search_end - search_start;
+
         if (hole_size > max_hole_size) {
                 max_hole_start = search_start;
                 max_hole_size = hole_size;
@@ -1543,6 +1579,7 @@ error:
 
 int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
 {
+        struct request_queue *q;
         struct btrfs_trans_handle *trans;
         struct btrfs_device *device;
         struct block_device *bdev;
@@ -1612,6 +1649,9 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
 
         lock_chunks(root);
 
+        q = bdev_get_queue(bdev);
+        if (blk_queue_discard(q))
+                device->can_discard = 1;
         device->writeable = 1;
         device->work.func = pending_bios_fn;
         generate_random_uuid(device->uuid);
@@ -1647,6 +1687,8 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
         root->fs_info->fs_devices->num_devices++;
         root->fs_info->fs_devices->open_devices++;
         root->fs_info->fs_devices->rw_devices++;
+        if (device->can_discard)
+                root->fs_info->fs_devices->num_can_discard++;
         root->fs_info->fs_devices->total_rw_bytes += device->total_bytes;
 
         if (!blk_queue_nonrot(bdev_get_queue(bdev)))
@@ -2413,9 +2455,10 @@ static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
                         total_avail = device->total_bytes - device->bytes_used;
                 else
                         total_avail = 0;
-                /* avail is off by max(alloc_start, 1MB), but that is the same
-                 * for all devices, so it doesn't hurt the sorting later on
-                 */
+
+                /* If there is no space on this device, skip it. */
+                if (total_avail == 0)
+                        continue;
 
                 ret = find_free_dev_extent(trans, device,
                                            max_stripe_size * dev_stripes,
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 7c12d61ae7ae..6d866db4e177 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -48,6 +48,7 @@ struct btrfs_device {
         int writeable;
         int in_fs_metadata;
         int missing;
+        int can_discard;
 
         spinlock_t io_lock;
 
@@ -104,6 +105,7 @@ struct btrfs_fs_devices {
         u64 rw_devices;
         u64 missing_devices;
         u64 total_rw_bytes;
+        u64 num_can_discard;
         struct block_device *latest_bdev;
 
         /* all of the devices in the FS, protected by a mutex