diff options
Diffstat (limited to 'fs/btrfs/file.c')
| -rw-r--r-- | fs/btrfs/file.c | 2399 |
1 files changed, 2027 insertions, 372 deletions
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index feaa13b105d..1f2b99cb55e 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -24,71 +24,459 @@ #include <linux/string.h> #include <linux/backing-dev.h> #include <linux/mpage.h> +#include <linux/aio.h> +#include <linux/falloc.h> #include <linux/swap.h> #include <linux/writeback.h> #include <linux/statfs.h> #include <linux/compat.h> +#include <linux/slab.h> +#include <linux/btrfs.h> #include "ctree.h" #include "disk-io.h" #include "transaction.h" #include "btrfs_inode.h" -#include "ioctl.h" #include "print-tree.h" #include "tree-log.h" #include "locking.h" -#include "compat.h" +#include "volumes.h" +#include "qgroup.h" +static struct kmem_cache *btrfs_inode_defrag_cachep; +/* + * when auto defrag is enabled we + * queue up these defrag structs to remember which + * inodes need defragging passes + */ +struct inode_defrag { + struct rb_node rb_node; + /* objectid */ + u64 ino; + /* + * transid where the defrag was added, we search for + * extents newer than this + */ + u64 transid; + + /* root objectid */ + u64 root; + + /* last offset we were able to defrag */ + u64 last_offset; + + /* if we've wrapped around back to zero once already */ + int cycled; +}; + +static int __compare_inode_defrag(struct inode_defrag *defrag1, + struct inode_defrag *defrag2) +{ + if (defrag1->root > defrag2->root) + return 1; + else if (defrag1->root < defrag2->root) + return -1; + else if (defrag1->ino > defrag2->ino) + return 1; + else if (defrag1->ino < defrag2->ino) + return -1; + else + return 0; +} + +/* pop a record for an inode into the defrag tree. The lock + * must be held already + * + * If you're inserting a record for an older transid than an + * existing record, the transid already in the tree is lowered + * + * If an existing record is found the defrag item you + * pass in is freed + */ +static int __btrfs_add_inode_defrag(struct inode *inode, + struct inode_defrag *defrag) +{ + struct btrfs_root *root = BTRFS_I(inode)->root; + struct inode_defrag *entry; + struct rb_node **p; + struct rb_node *parent = NULL; + int ret; + + p = &root->fs_info->defrag_inodes.rb_node; + while (*p) { + parent = *p; + entry = rb_entry(parent, struct inode_defrag, rb_node); + + ret = __compare_inode_defrag(defrag, entry); + if (ret < 0) + p = &parent->rb_left; + else if (ret > 0) + p = &parent->rb_right; + else { + /* if we're reinserting an entry for + * an old defrag run, make sure to + * lower the transid of our existing record + */ + if (defrag->transid < entry->transid) + entry->transid = defrag->transid; + if (defrag->last_offset > entry->last_offset) + entry->last_offset = defrag->last_offset; + return -EEXIST; + } + } + set_bit(BTRFS_INODE_IN_DEFRAG, &BTRFS_I(inode)->runtime_flags); + rb_link_node(&defrag->rb_node, parent, p); + rb_insert_color(&defrag->rb_node, &root->fs_info->defrag_inodes); + return 0; +} + +static inline int __need_auto_defrag(struct btrfs_root *root) +{ + if (!btrfs_test_opt(root, AUTO_DEFRAG)) + return 0; + + if (btrfs_fs_closing(root->fs_info)) + return 0; + + return 1; +} + +/* + * insert a defrag record for this inode if auto defrag is + * enabled + */ +int btrfs_add_inode_defrag(struct btrfs_trans_handle *trans, + struct inode *inode) +{ + struct btrfs_root *root = BTRFS_I(inode)->root; + struct inode_defrag *defrag; + u64 transid; + int ret; + + if (!__need_auto_defrag(root)) + return 0; + + if (test_bit(BTRFS_INODE_IN_DEFRAG, &BTRFS_I(inode)->runtime_flags)) + return 0; + + if (trans) + transid = trans->transid; + else + transid = BTRFS_I(inode)->root->last_trans; + + defrag = kmem_cache_zalloc(btrfs_inode_defrag_cachep, GFP_NOFS); + if (!defrag) + return -ENOMEM; + + defrag->ino = btrfs_ino(inode); + defrag->transid = transid; + defrag->root = root->root_key.objectid; + + spin_lock(&root->fs_info->defrag_inodes_lock); + if (!test_bit(BTRFS_INODE_IN_DEFRAG, &BTRFS_I(inode)->runtime_flags)) { + /* + * If we set IN_DEFRAG flag and evict the inode from memory, + * and then re-read this inode, this new inode doesn't have + * IN_DEFRAG flag. At the case, we may find the existed defrag. + */ + ret = __btrfs_add_inode_defrag(inode, defrag); + if (ret) + kmem_cache_free(btrfs_inode_defrag_cachep, defrag); + } else { + kmem_cache_free(btrfs_inode_defrag_cachep, defrag); + } + spin_unlock(&root->fs_info->defrag_inodes_lock); + return 0; +} + +/* + * Requeue the defrag object. If there is a defrag object that points to + * the same inode in the tree, we will merge them together (by + * __btrfs_add_inode_defrag()) and free the one that we want to requeue. + */ +static void btrfs_requeue_inode_defrag(struct inode *inode, + struct inode_defrag *defrag) +{ + struct btrfs_root *root = BTRFS_I(inode)->root; + int ret; + + if (!__need_auto_defrag(root)) + goto out; + + /* + * Here we don't check the IN_DEFRAG flag, because we need merge + * them together. + */ + spin_lock(&root->fs_info->defrag_inodes_lock); + ret = __btrfs_add_inode_defrag(inode, defrag); + spin_unlock(&root->fs_info->defrag_inodes_lock); + if (ret) + goto out; + return; +out: + kmem_cache_free(btrfs_inode_defrag_cachep, defrag); +} + +/* + * pick the defragable inode that we want, if it doesn't exist, we will get + * the next one. + */ +static struct inode_defrag * +btrfs_pick_defrag_inode(struct btrfs_fs_info *fs_info, u64 root, u64 ino) +{ + struct inode_defrag *entry = NULL; + struct inode_defrag tmp; + struct rb_node *p; + struct rb_node *parent = NULL; + int ret; + + tmp.ino = ino; + tmp.root = root; + + spin_lock(&fs_info->defrag_inodes_lock); + p = fs_info->defrag_inodes.rb_node; + while (p) { + parent = p; + entry = rb_entry(parent, struct inode_defrag, rb_node); + + ret = __compare_inode_defrag(&tmp, entry); + if (ret < 0) + p = parent->rb_left; + else if (ret > 0) + p = parent->rb_right; + else + goto out; + } + + if (parent && __compare_inode_defrag(&tmp, entry) > 0) { + parent = rb_next(parent); + if (parent) + entry = rb_entry(parent, struct inode_defrag, rb_node); + else + entry = NULL; + } +out: + if (entry) + rb_erase(parent, &fs_info->defrag_inodes); + spin_unlock(&fs_info->defrag_inodes_lock); + return entry; +} + +void btrfs_cleanup_defrag_inodes(struct btrfs_fs_info *fs_info) +{ + struct inode_defrag *defrag; + struct rb_node *node; + + spin_lock(&fs_info->defrag_inodes_lock); + node = rb_first(&fs_info->defrag_inodes); + while (node) { + rb_erase(node, &fs_info->defrag_inodes); + defrag = rb_entry(node, struct inode_defrag, rb_node); + kmem_cache_free(btrfs_inode_defrag_cachep, defrag); + + if (need_resched()) { + spin_unlock(&fs_info->defrag_inodes_lock); + cond_resched(); + spin_lock(&fs_info->defrag_inodes_lock); + } + + node = rb_first(&fs_info->defrag_inodes); + } + spin_unlock(&fs_info->defrag_inodes_lock); +} + +#define BTRFS_DEFRAG_BATCH 1024 + +static int __btrfs_run_defrag_inode(struct btrfs_fs_info *fs_info, + struct inode_defrag *defrag) +{ + struct btrfs_root *inode_root; + struct inode *inode; + struct btrfs_key key; + struct btrfs_ioctl_defrag_range_args range; + int num_defrag; + int index; + int ret; + + /* get the inode */ + key.objectid = defrag->root; + btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY); + key.offset = (u64)-1; + + index = srcu_read_lock(&fs_info->subvol_srcu); + + inode_root = btrfs_read_fs_root_no_name(fs_info, &key); + if (IS_ERR(inode_root)) { + ret = PTR_ERR(inode_root); + goto cleanup; + } + + key.objectid = defrag->ino; + btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY); + key.offset = 0; + inode = btrfs_iget(fs_info->sb, &key, inode_root, NULL); + if (IS_ERR(inode)) { + ret = PTR_ERR(inode); + goto cleanup; + } + srcu_read_unlock(&fs_info->subvol_srcu, index); + + /* do a chunk of defrag */ + clear_bit(BTRFS_INODE_IN_DEFRAG, &BTRFS_I(inode)->runtime_flags); + memset(&range, 0, sizeof(range)); + range.len = (u64)-1; + range.start = defrag->last_offset; + + sb_start_write(fs_info->sb); + num_defrag = btrfs_defrag_file(inode, NULL, &range, defrag->transid, + BTRFS_DEFRAG_BATCH); + sb_end_write(fs_info->sb); + /* + * if we filled the whole defrag batch, there + * must be more work to do. Queue this defrag + * again + */ + if (num_defrag == BTRFS_DEFRAG_BATCH) { + defrag->last_offset = range.start; + btrfs_requeue_inode_defrag(inode, defrag); + } else if (defrag->last_offset && !defrag->cycled) { + /* + * we didn't fill our defrag batch, but + * we didn't start at zero. Make sure we loop + * around to the start of the file. + */ + defrag->last_offset = 0; + defrag->cycled = 1; + btrfs_requeue_inode_defrag(inode, defrag); + } else { + kmem_cache_free(btrfs_inode_defrag_cachep, defrag); + } + + iput(inode); + return 0; +cleanup: + srcu_read_unlock(&fs_info->subvol_srcu, index); + kmem_cache_free(btrfs_inode_defrag_cachep, defrag); + return ret; +} + +/* + * run through the list of inodes in the FS that need + * defragging + */ +int btrfs_run_defrag_inodes(struct btrfs_fs_info *fs_info) +{ + struct inode_defrag *defrag; + u64 first_ino = 0; + u64 root_objectid = 0; + + atomic_inc(&fs_info->defrag_running); + while (1) { + /* Pause the auto defragger. */ + if (test_bit(BTRFS_FS_STATE_REMOUNTING, + &fs_info->fs_state)) + break; + + if (!__need_auto_defrag(fs_info->tree_root)) + break; + + /* find an inode to defrag */ + defrag = btrfs_pick_defrag_inode(fs_info, root_objectid, + first_ino); + if (!defrag) { + if (root_objectid || first_ino) { + root_objectid = 0; + first_ino = 0; + continue; + } else { + break; + } + } + + first_ino = defrag->ino + 1; + root_objectid = defrag->root; + + __btrfs_run_defrag_inode(fs_info, defrag); + } + atomic_dec(&fs_info->defrag_running); + + /* + * during unmount, we use the transaction_wait queue to + * wait for the defragger to stop + */ + wake_up(&fs_info->transaction_wait); + return 0; +} /* simple helper to fault in pages and copy. This should go away * and be replaced with calls into generic code. */ static noinline int btrfs_copy_from_user(loff_t pos, int num_pages, - int write_bytes, + size_t write_bytes, struct page **prepared_pages, - const char __user *buf) + struct iov_iter *i) { - long page_fault = 0; - int i; + size_t copied = 0; + size_t total_copied = 0; + int pg = 0; int offset = pos & (PAGE_CACHE_SIZE - 1); - for (i = 0; i < num_pages && write_bytes > 0; i++, offset = 0) { + while (write_bytes > 0) { size_t count = min_t(size_t, PAGE_CACHE_SIZE - offset, write_bytes); - struct page *page = prepared_pages[i]; - fault_in_pages_readable(buf, count); + struct page *page = prepared_pages[pg]; + /* + * Copy data from userspace to the current page + */ + copied = iov_iter_copy_from_user_atomic(page, i, offset, count); - /* Copy data from userspace to the current page */ - kmap(page); - page_fault = __copy_from_user(page_address(page) + offset, - buf, count); /* Flush processor's dcache for this page */ flush_dcache_page(page); - kunmap(page); - buf += count; - write_bytes -= count; - if (page_fault) + /* + * if we get a partial write, we can end up with + * partially up to date pages. These add + * a lot of complexity, so make sure they don't + * happen by forcing this copy to be retried. + * + * The rest of the btrfs_file_write code will fall + * back to page at a time copies after we return 0. + */ + if (!PageUptodate(page) && copied < count) + copied = 0; + + iov_iter_advance(i, copied); + write_bytes -= copied; + total_copied += copied; + + /* Return to btrfs_file_write_iter to fault page */ + if (unlikely(copied == 0)) break; + + if (unlikely(copied < PAGE_CACHE_SIZE - offset)) { + offset += copied; + } else { + pg++; + offset = 0; + } } - return page_fault ? -EFAULT : 0; + return total_copied; } /* * unlocks pages after btrfs_file_write is done with them */ -static noinline void btrfs_drop_pages(struct page **pages, size_t num_pages) +static void btrfs_drop_pages(struct page **pages, size_t num_pages) { size_t i; for (i = 0; i < num_pages; i++) { - if (!pages[i]) - break; /* page checked is some magic around finding pages that * have been modified without going through btrfs_set_page_dirty - * clear it here + * clear it here. There should be no need to mark the pages + * accessed as prepare_pages should have marked them accessed + * in prepare_pages via find_or_create_page() */ ClearPageChecked(pages[i]); unlock_page(pages[i]); - mark_page_accessed(pages[i]); page_cache_release(pages[i]); } } @@ -101,17 +489,13 @@ static noinline void btrfs_drop_pages(struct page **pages, size_t num_pages) * this also makes the decision about creating an inline extent vs * doing real data extents, marking pages dirty and delalloc as required. */ -static noinline int dirty_and_release_pages(struct btrfs_trans_handle *trans, - struct btrfs_root *root, - struct file *file, - struct page **pages, - size_t num_pages, - loff_t pos, - size_t write_bytes) +int btrfs_dirty_pages(struct btrfs_root *root, struct inode *inode, + struct page **pages, size_t num_pages, + loff_t pos, size_t write_bytes, + struct extent_state **cached) { int err = 0; int i; - struct inode *inode = fdentry(file)->d_inode; u64 num_bytes; u64 start_pos; u64 end_of_last_block; @@ -119,11 +503,11 @@ static noinline int dirty_and_release_pages(struct btrfs_trans_handle *trans, loff_t isize = i_size_read(inode); start_pos = pos & ~((u64)root->sectorsize - 1); - num_bytes = (write_bytes + pos - start_pos + - root->sectorsize - 1) & ~((u64)root->sectorsize - 1); + num_bytes = ALIGN(write_bytes + pos - start_pos, root->sectorsize); end_of_last_block = start_pos + num_bytes - 1; - err = btrfs_set_extent_delalloc(inode, start_pos, end_of_last_block); + err = btrfs_set_extent_delalloc(inode, start_pos, end_of_last_block, + cached); if (err) return err; @@ -133,32 +517,35 @@ static noinline int dirty_and_release_pages(struct btrfs_trans_handle *trans, ClearPageChecked(p); set_page_dirty(p); } - if (end_pos > isize) { + + /* + * we've only changed i_size in ram, and we haven't updated + * the disk i_size. There is no need to log the inode + * at this time. + */ + if (end_pos > isize) i_size_write(inode, end_pos); - /* we've only changed i_size in ram, and we haven't updated - * the disk i_size. There is no need to log the inode - * at this time. - */ - } - return err; + return 0; } /* * this drops all the extents in the cache that intersect the range * [start, end]. Existing extents are split as required. */ -int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end, - int skip_pinned) +void btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end, + int skip_pinned) { struct extent_map *em; struct extent_map *split = NULL; struct extent_map *split2 = NULL; struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; u64 len = end - start + 1; + u64 gen; int ret; int testend = 1; unsigned long flags; int compressed = 0; + bool modified; WARN_ON(end < start); if (end == (u64)-1) { @@ -166,10 +553,15 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end, testend = 0; } while (1) { + int no_splits = 0; + + modified = false; if (!split) - split = alloc_extent_map(GFP_NOFS); + split = alloc_extent_map(); if (!split2) - split2 = alloc_extent_map(GFP_NOFS); + split2 = alloc_extent_map(); + if (!split || !split2) + no_splits = 1; write_lock(&em_tree->lock); em = lookup_extent_mapping(em_tree, start, len); @@ -178,6 +570,7 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end, break; } flags = em->flags; + gen = em->generation; if (skip_pinned && test_bit(EXTENT_FLAG_PINNED, &em->flags)) { if (testend && em->start + em->len >= start + len) { free_extent_map(em); @@ -193,52 +586,90 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end, } compressed = test_bit(EXTENT_FLAG_COMPRESSED, &em->flags); clear_bit(EXTENT_FLAG_PINNED, &em->flags); - remove_extent_mapping(em_tree, em); + clear_bit(EXTENT_FLAG_LOGGING, &flags); + modified = !list_empty(&em->list); + if (no_splits) + goto next; - if (em->block_start < EXTENT_MAP_LAST_BYTE && - em->start < start) { + if (em->start < start) { split->start = em->start; split->len = start - em->start; - split->orig_start = em->orig_start; - split->block_start = em->block_start; - if (compressed) - split->block_len = em->block_len; - else - split->block_len = split->len; + if (em->block_start < EXTENT_MAP_LAST_BYTE) { + split->orig_start = em->orig_start; + split->block_start = em->block_start; + if (compressed) + split->block_len = em->block_len; + else + split->block_len = split->len; + split->orig_block_len = max(split->block_len, + em->orig_block_len); + split->ram_bytes = em->ram_bytes; + } else { + split->orig_start = split->start; + split->block_len = 0; + split->block_start = em->block_start; + split->orig_block_len = 0; + split->ram_bytes = split->len; + } + + split->generation = gen; split->bdev = em->bdev; split->flags = flags; - ret = add_extent_mapping(em_tree, split); - BUG_ON(ret); + split->compress_type = em->compress_type; + replace_extent_mapping(em_tree, em, split, modified); free_extent_map(split); split = split2; split2 = NULL; } - if (em->block_start < EXTENT_MAP_LAST_BYTE && - testend && em->start + em->len > start + len) { + if (testend && em->start + em->len > start + len) { u64 diff = start + len - em->start; split->start = start + len; split->len = em->start + em->len - (start + len); split->bdev = em->bdev; split->flags = flags; - - if (compressed) { - split->block_len = em->block_len; - split->block_start = em->block_start; - split->orig_start = em->orig_start; + split->compress_type = em->compress_type; + split->generation = gen; + + if (em->block_start < EXTENT_MAP_LAST_BYTE) { + split->orig_block_len = max(em->block_len, + em->orig_block_len); + + split->ram_bytes = em->ram_bytes; + if (compressed) { + split->block_len = em->block_len; + split->block_start = em->block_start; + split->orig_start = em->orig_start; + } else { + split->block_len = split->len; + split->block_start = em->block_start + + diff; + split->orig_start = em->orig_start; + } } else { - split->block_len = split->len; - split->block_start = em->block_start + diff; + split->ram_bytes = split->len; split->orig_start = split->start; + split->block_len = 0; + split->block_start = em->block_start; + split->orig_block_len = 0; } - ret = add_extent_mapping(em_tree, split); - BUG_ON(ret); + if (extent_map_in_tree(em)) { + replace_extent_mapping(em_tree, em, split, + modified); + } else { + ret = add_extent_mapping(em_tree, split, + modified); + ASSERT(ret == 0); /* Logic error */ + } free_extent_map(split); split = NULL; } +next: + if (extent_map_in_tree(em)) + remove_extent_mapping(em_tree, em); write_unlock(&em_tree->lock); /* once for us */ @@ -250,7 +681,6 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end, free_extent_map(split); if (split2) free_extent_map(split2); - return 0; } /* @@ -262,15 +692,19 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end, * it is either truncated or split. Anything entirely inside the range * is deleted from the tree. */ -int btrfs_drop_extents(struct btrfs_trans_handle *trans, struct inode *inode, - u64 start, u64 end, u64 *hint_byte, int drop_cache) +int __btrfs_drop_extents(struct btrfs_trans_handle *trans, + struct btrfs_root *root, struct inode *inode, + struct btrfs_path *path, u64 start, u64 end, + u64 *drop_end, int drop_cache, + int replace_extent, + u32 extent_item_size, + int *key_inserted) { - struct btrfs_root *root = BTRFS_I(inode)->root; struct extent_buffer *leaf; struct btrfs_file_extent_item *fi; - struct btrfs_path *path; struct btrfs_key key; struct btrfs_key new_key; + u64 ino = btrfs_ino(inode); u64 search_start = start; u64 disk_bytenr = 0; u64 num_bytes = 0; @@ -281,28 +715,34 @@ int btrfs_drop_extents(struct btrfs_trans_handle *trans, struct inode *inode, int extent_type; int recow; int ret; + int modify_tree = -1; + int update_refs; + int found = 0; + int leafs_visited = 0; if (drop_cache) btrfs_drop_extent_cache(inode, start, end - 1, 0); - path = btrfs_alloc_path(); - if (!path) - return -ENOMEM; + if (start >= BTRFS_I(inode)->disk_i_size && !replace_extent) + modify_tree = 0; + update_refs = (test_bit(BTRFS_ROOT_REF_COWS, &root->state) || + root == root->fs_info->tree_root); while (1) { recow = 0; - ret = btrfs_lookup_file_extent(trans, root, path, inode->i_ino, - search_start, -1); + ret = btrfs_lookup_file_extent(trans, root, path, ino, + search_start, modify_tree); if (ret < 0) break; if (ret > 0 && path->slots[0] > 0 && search_start == start) { leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &key, path->slots[0] - 1); - if (key.objectid == inode->i_ino && + if (key.objectid == ino && key.type == BTRFS_EXTENT_DATA_KEY) path->slots[0]--; } ret = 0; + leafs_visited++; next_slot: leaf = path->nodes[0]; if (path->slots[0] >= btrfs_header_nritems(leaf)) { @@ -314,12 +754,13 @@ next_slot: ret = 0; break; } + leafs_visited++; leaf = path->nodes[0]; recow = 1; } btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); - if (key.objectid > inode->i_ino || + if (key.objectid > ino || key.type > BTRFS_EXTENT_DATA_KEY || key.offset >= end) break; @@ -336,20 +777,35 @@ next_slot: btrfs_file_extent_num_bytes(leaf, fi); } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { extent_end = key.offset + - btrfs_file_extent_inline_len(leaf, fi); + btrfs_file_extent_inline_len(leaf, + path->slots[0], fi); } else { WARN_ON(1); extent_end = search_start; } + /* + * Don't skip extent items representing 0 byte lengths. They + * used to be created (bug) if while punching holes we hit + * -ENOSPC condition. So if we find one here, just ensure we + * delete it, otherwise we would insert a new file extent item + * with the same key (offset) as that 0 bytes length file + * extent item in the call to setup_items_for_insert() later + * in this function. + */ + if (extent_end == key.offset && extent_end >= search_start) + goto delete_extent_item; + if (extent_end <= search_start) { path->slots[0]++; goto next_slot; } + found = 1; search_start = max(key.offset, start); - if (recow) { - btrfs_release_path(root, path); + if (recow || !modify_tree) { + modify_tree = -1; + btrfs_release_path(path); continue; } @@ -359,14 +815,17 @@ next_slot: */ if (start > key.offset && end < extent_end) { BUG_ON(del_nr > 0); - BUG_ON(extent_type == BTRFS_FILE_EXTENT_INLINE); + if (extent_type == BTRFS_FILE_EXTENT_INLINE) { + ret = -EOPNOTSUPP; + break; + } memcpy(&new_key, &key, sizeof(new_key)); new_key.offset = start; ret = btrfs_duplicate_item(trans, root, path, &new_key); if (ret == -EAGAIN) { - btrfs_release_path(root, path); + btrfs_release_path(path); continue; } if (ret < 0) @@ -387,14 +846,13 @@ next_slot: extent_end - start); btrfs_mark_buffer_dirty(leaf); - if (disk_bytenr > 0) { + if (update_refs && disk_bytenr > 0) { ret = btrfs_inc_extent_ref(trans, root, disk_bytenr, num_bytes, 0, root->root_key.objectid, new_key.objectid, - start - extent_offset); - BUG_ON(ret); - *hint_byte = disk_bytenr; + start - extent_offset, 1); + BUG_ON(ret); /* -ENOMEM */ } key.offset = start; } @@ -403,21 +861,22 @@ next_slot: * | -------- extent -------- | */ if (start <= key.offset && end < extent_end) { - BUG_ON(extent_type == BTRFS_FILE_EXTENT_INLINE); + if (extent_type == BTRFS_FILE_EXTENT_INLINE) { + ret = -EOPNOTSUPP; + break; + } memcpy(&new_key, &key, sizeof(new_key)); new_key.offset = end; - btrfs_set_item_key_safe(trans, root, path, &new_key); + btrfs_set_item_key_safe(root, path, &new_key); extent_offset += end - key.offset; btrfs_set_file_extent_offset(leaf, fi, extent_offset); btrfs_set_file_extent_num_bytes(leaf, fi, extent_end - end); btrfs_mark_buffer_dirty(leaf); - if (disk_bytenr > 0) { + if (update_refs && disk_bytenr > 0) inode_sub_bytes(inode, end - key.offset); - *hint_byte = disk_bytenr; - } break; } @@ -428,15 +887,16 @@ next_slot: */ if (start > key.offset && end >= extent_end) { BUG_ON(del_nr > 0); - BUG_ON(extent_type == BTRFS_FILE_EXTENT_INLINE); + if (extent_type == BTRFS_FILE_EXTENT_INLINE) { + ret = -EOPNOTSUPP; + break; + } btrfs_set_file_extent_num_bytes(leaf, fi, start - key.offset); btrfs_mark_buffer_dirty(leaf); - if (disk_bytenr > 0) { + if (update_refs && disk_bytenr > 0) inode_sub_bytes(inode, extent_end - start); - *hint_byte = disk_bytenr; - } if (end == extent_end) break; @@ -449,6 +909,7 @@ next_slot: * | ------ extent ------ | */ if (start <= key.offset && end >= extent_end) { +delete_extent_item: if (del_nr == 0) { del_slot = path->slots[0]; del_nr = 1; @@ -457,21 +918,21 @@ next_slot: del_nr++; } - if (extent_type == BTRFS_FILE_EXTENT_INLINE) { + if (update_refs && + extent_type == BTRFS_FILE_EXTENT_INLINE) { inode_sub_bytes(inode, extent_end - key.offset); extent_end = ALIGN(extent_end, root->sectorsize); - } else if (disk_bytenr > 0) { + } else if (update_refs && disk_bytenr > 0) { ret = btrfs_free_extent(trans, root, disk_bytenr, num_bytes, 0, root->root_key.objectid, key.objectid, key.offset - - extent_offset); - BUG_ON(ret); + extent_offset, 0); + BUG_ON(ret); /* -ENOMEM */ inode_sub_bytes(inode, extent_end - key.offset); - *hint_byte = disk_bytenr; } if (end == extent_end) @@ -484,29 +945,90 @@ next_slot: ret = btrfs_del_items(trans, root, path, del_slot, del_nr); - BUG_ON(ret); + if (ret) { + btrfs_abort_transaction(trans, root, ret); + break; + } del_nr = 0; del_slot = 0; - btrfs_release_path(root, path); + btrfs_release_path(path); continue; } BUG_ON(1); } - if (del_nr > 0) { + if (!ret && del_nr > 0) { + /* + * Set path->slots[0] to first slot, so that after the delete + * if items are move off from our leaf to its immediate left or + * right neighbor leafs, we end up with a correct and adjusted + * path->slots[0] for our insertion (if replace_extent != 0). + */ + path->slots[0] = del_slot; ret = btrfs_del_items(trans, root, path, del_slot, del_nr); - BUG_ON(ret); + if (ret) + btrfs_abort_transaction(trans, root, ret); + } + + leaf = path->nodes[0]; + /* + * If btrfs_del_items() was called, it might have deleted a leaf, in + * which case it unlocked our path, so check path->locks[0] matches a + * write lock. + */ + if (!ret && replace_extent && leafs_visited == 1 && + (path->locks[0] == BTRFS_WRITE_LOCK_BLOCKING || + path->locks[0] == BTRFS_WRITE_LOCK) && + btrfs_leaf_free_space(root, leaf) >= + sizeof(struct btrfs_item) + extent_item_size) { + + key.objectid = ino; + key.type = BTRFS_EXTENT_DATA_KEY; + key.offset = start; + if (!del_nr && path->slots[0] < btrfs_header_nritems(leaf)) { + struct btrfs_key slot_key; + + btrfs_item_key_to_cpu(leaf, &slot_key, path->slots[0]); + if (btrfs_comp_cpu_keys(&key, &slot_key) > 0) + path->slots[0]++; + } + setup_items_for_insert(root, path, &key, + &extent_item_size, + extent_item_size, + sizeof(struct btrfs_item) + + extent_item_size, 1); + *key_inserted = 1; } + if (!replace_extent || !(*key_inserted)) + btrfs_release_path(path); + if (drop_end) + *drop_end = found ? min(end, extent_end) : end; + return ret; +} + +int btrfs_drop_extents(struct btrfs_trans_handle *trans, + struct btrfs_root *root, struct inode *inode, u64 start, + u64 end, int drop_cache) +{ + struct btrfs_path *path; + int ret; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + ret = __btrfs_drop_extents(trans, root, inode, path, start, end, NULL, + drop_cache, 0, 0, NULL); btrfs_free_path(path); return ret; } static int extent_mergeable(struct extent_buffer *leaf, int slot, - u64 objectid, u64 bytenr, u64 *start, u64 *end) + u64 objectid, u64 bytenr, u64 orig_offset, + u64 *start, u64 *end) { struct btrfs_file_extent_item *fi; struct btrfs_key key; @@ -522,6 +1044,7 @@ static int extent_mergeable(struct extent_buffer *leaf, int slot, fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item); if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG || btrfs_file_extent_disk_bytenr(leaf, fi) != bytenr || + btrfs_file_extent_offset(leaf, fi) != key.offset - orig_offset || btrfs_file_extent_compression(leaf, fi) || btrfs_file_extent_encryption(leaf, fi) || btrfs_file_extent_other_encoding(leaf, fi)) @@ -561,26 +1084,29 @@ int btrfs_mark_extent_written(struct btrfs_trans_handle *trans, u64 split; int del_nr = 0; int del_slot = 0; + int recow; int ret; - - btrfs_drop_extent_cache(inode, start, end - 1, 0); + u64 ino = btrfs_ino(inode); path = btrfs_alloc_path(); - BUG_ON(!path); + if (!path) + return -ENOMEM; again: + recow = 0; split = start; - key.objectid = inode->i_ino; + key.objectid = ino; key.type = BTRFS_EXTENT_DATA_KEY; key.offset = split; ret = btrfs_search_slot(trans, root, &key, path, -1, 1); + if (ret < 0) + goto out; if (ret > 0 && path->slots[0] > 0) path->slots[0]--; leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); - BUG_ON(key.objectid != inode->i_ino || - key.type != BTRFS_EXTENT_DATA_KEY); + BUG_ON(key.objectid != ino || key.type != BTRFS_EXTENT_DATA_KEY); fi = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); BUG_ON(btrfs_file_extent_type(leaf, fi) != @@ -591,29 +1117,90 @@ again: bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi); orig_offset = key.offset - btrfs_file_extent_offset(leaf, fi); + memcpy(&new_key, &key, sizeof(new_key)); + + if (start == key.offset && end < extent_end) { + other_start = 0; + other_end = start; + if (extent_mergeable(leaf, path->slots[0] - 1, + ino, bytenr, orig_offset, + &other_start, &other_end)) { + new_key.offset = end; + btrfs_set_item_key_safe(root, path, &new_key); + fi = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_file_extent_item); + btrfs_set_file_extent_generation(leaf, fi, + trans->transid); + btrfs_set_file_extent_num_bytes(leaf, fi, + extent_end - end); + btrfs_set_file_extent_offset(leaf, fi, + end - orig_offset); + fi = btrfs_item_ptr(leaf, path->slots[0] - 1, + struct btrfs_file_extent_item); + btrfs_set_file_extent_generation(leaf, fi, + trans->transid); + btrfs_set_file_extent_num_bytes(leaf, fi, + end - other_start); + btrfs_mark_buffer_dirty(leaf); + goto out; + } + } + + if (start > key.offset && end == extent_end) { + other_start = end; + other_end = 0; + if (extent_mergeable(leaf, path->slots[0] + 1, + ino, bytenr, orig_offset, + &other_start, &other_end)) { + fi = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_file_extent_item); + btrfs_set_file_extent_num_bytes(leaf, fi, + start - key.offset); + btrfs_set_file_extent_generation(leaf, fi, + trans->transid); + path->slots[0]++; + new_key.offset = start; + btrfs_set_item_key_safe(root, path, &new_key); + + fi = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_file_extent_item); + btrfs_set_file_extent_generation(leaf, fi, + trans->transid); + btrfs_set_file_extent_num_bytes(leaf, fi, + other_end - start); + btrfs_set_file_extent_offset(leaf, fi, + start - orig_offset); + btrfs_mark_buffer_dirty(leaf); + goto out; + } + } while (start > key.offset || end < extent_end) { if (key.offset == start) split = end; - memcpy(&new_key, &key, sizeof(new_key)); new_key.offset = split; ret = btrfs_duplicate_item(trans, root, path, &new_key); if (ret == -EAGAIN) { - btrfs_release_path(root, path); + btrfs_release_path(path); goto again; } - BUG_ON(ret < 0); + if (ret < 0) { + btrfs_abort_transaction(trans, root, ret); + goto out; + } leaf = path->nodes[0]; fi = btrfs_item_ptr(leaf, path->slots[0] - 1, struct btrfs_file_extent_item); + btrfs_set_file_extent_generation(leaf, fi, trans->transid); btrfs_set_file_extent_num_bytes(leaf, fi, split - key.offset); fi = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); + btrfs_set_file_extent_generation(leaf, fi, trans->transid); btrfs_set_file_extent_offset(leaf, fi, split - orig_offset); btrfs_set_file_extent_num_bytes(leaf, fi, extent_end - split); @@ -621,8 +1208,8 @@ again: ret = btrfs_inc_extent_ref(trans, root, bytenr, num_bytes, 0, root->root_key.objectid, - inode->i_ino, orig_offset); - BUG_ON(ret); + ino, orig_offset, 1); + BUG_ON(ret); /* -ENOMEM */ if (split == start) { key.offset = start; @@ -631,292 +1218,592 @@ again: path->slots[0]--; extent_end = end; } + recow = 1; } - fi = btrfs_item_ptr(leaf, path->slots[0], - struct btrfs_file_extent_item); - other_start = end; other_end = 0; - if (extent_mergeable(leaf, path->slots[0] + 1, inode->i_ino, - bytenr, &other_start, &other_end)) { + if (extent_mergeable(leaf, path->slots[0] + 1, + ino, bytenr, orig_offset, + &other_start, &other_end)) { + if (recow) { + btrfs_release_path(path); + goto again; + } extent_end = other_end; del_slot = path->slots[0] + 1; del_nr++; ret = btrfs_free_extent(trans, root, bytenr, num_bytes, 0, root->root_key.objectid, - inode->i_ino, orig_offset); - BUG_ON(ret); + ino, orig_offset, 0); + BUG_ON(ret); /* -ENOMEM */ } other_start = 0; other_end = start; - if (extent_mergeable(leaf, path->slots[0] - 1, inode->i_ino, - bytenr, &other_start, &other_end)) { + if (extent_mergeable(leaf, path->slots[0] - 1, + ino, bytenr, orig_offset, + &other_start, &other_end)) { + if (recow) { + btrfs_release_path(path); + goto again; + } key.offset = other_start; del_slot = path->slots[0]; del_nr++; ret = btrfs_free_extent(trans, root, bytenr, num_bytes, 0, root->root_key.objectid, - inode->i_ino, orig_offset); - BUG_ON(ret); + ino, orig_offset, 0); + BUG_ON(ret); /* -ENOMEM */ } if (del_nr == 0) { + fi = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_file_extent_item); btrfs_set_file_extent_type(leaf, fi, BTRFS_FILE_EXTENT_REG); + btrfs_set_file_extent_generation(leaf, fi, trans->transid); + btrfs_mark_buffer_dirty(leaf); + } else { + fi = btrfs_item_ptr(leaf, del_slot - 1, + struct btrfs_file_extent_item); + btrfs_set_file_extent_type(leaf, fi, + BTRFS_FILE_EXTENT_REG); + btrfs_set_file_extent_generation(leaf, fi, trans->transid); + btrfs_set_file_extent_num_bytes(leaf, fi, + extent_end - key.offset); btrfs_mark_buffer_dirty(leaf); - goto out; - } - - fi = btrfs_item_ptr(leaf, del_slot - 1, - struct btrfs_file_extent_item); - btrfs_set_file_extent_type(leaf, fi, BTRFS_FILE_EXTENT_REG); - btrfs_set_file_extent_num_bytes(leaf, fi, - extent_end - key.offset); - btrfs_mark_buffer_dirty(leaf); - ret = btrfs_del_items(trans, root, path, del_slot, del_nr); - BUG_ON(ret); + ret = btrfs_del_items(trans, root, path, del_slot, del_nr); + if (ret < 0) { + btrfs_abort_transaction(trans, root, ret); + goto out; + } + } out: btrfs_free_path(path); return 0; } /* - * this gets pages into the page cache and locks them down, it also properly - * waits for data=ordered extents to finish before allowing the pages to be - * modified. + * on error we return an unlocked page and the error value + * on success we return a locked page and 0 */ -static noinline int prepare_pages(struct btrfs_root *root, struct file *file, - struct page **pages, size_t num_pages, - loff_t pos, unsigned long first_index, - unsigned long last_index, size_t write_bytes) +static int prepare_uptodate_page(struct page *page, u64 pos, + bool force_uptodate) +{ + int ret = 0; + + if (((pos & (PAGE_CACHE_SIZE - 1)) || force_uptodate) && + !PageUptodate(page)) { + ret = btrfs_readpage(NULL, page); + if (ret) + return ret; + lock_page(page); + if (!PageUptodate(page)) { + unlock_page(page); + return -EIO; + } + } + return 0; +} + +/* + * this just gets pages into the page cache and locks them down. + */ +static noinline int prepare_pages(struct inode *inode, struct page **pages, + size_t num_pages, loff_t pos, + size_t write_bytes, bool force_uptodate) { int i; unsigned long index = pos >> PAGE_CACHE_SHIFT; - struct inode *inode = fdentry(file)->d_inode; + gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping); int err = 0; - u64 start_pos; - u64 last_pos; + int faili; - start_pos = pos & ~((u64)root->sectorsize - 1); - last_pos = ((u64)index + num_pages) << PAGE_CACHE_SHIFT; - - if (start_pos > inode->i_size) { - err = btrfs_cont_expand(inode, start_pos); - if (err) - return err; - } - - memset(pages, 0, num_pages * sizeof(struct page *)); -again: for (i = 0; i < num_pages; i++) { - pages[i] = grab_cache_page(inode->i_mapping, index + i); + pages[i] = find_or_create_page(inode->i_mapping, index + i, + mask | __GFP_WRITE); if (!pages[i]) { + faili = i - 1; err = -ENOMEM; - BUG_ON(1); + goto fail; + } + + if (i == 0) + err = prepare_uptodate_page(pages[i], pos, + force_uptodate); + if (i == num_pages - 1) + err = prepare_uptodate_page(pages[i], + pos + write_bytes, false); + if (err) { + page_cache_release(pages[i]); + faili = i - 1; + goto fail; } wait_on_page_writeback(pages[i]); } + + return 0; +fail: + while (faili >= 0) { + unlock_page(pages[faili]); + page_cache_release(pages[faili]); + faili--; + } + return err; + +} + +/* + * This function locks the extent and properly waits for data=ordered extents + * to finish before allowing the pages to be modified if need. + * + * The return value: + * 1 - the extent is locked + * 0 - the extent is not locked, and everything is OK + * -EAGAIN - need re-prepare the pages + * the other < 0 number - Something wrong happens + */ +static noinline int +lock_and_cleanup_extent_if_need(struct inode *inode, struct page **pages, + size_t num_pages, loff_t pos, + u64 *lockstart, u64 *lockend, + struct extent_state **cached_state) +{ + u64 start_pos; + u64 last_pos; + int i; + int ret = 0; + + start_pos = pos & ~((u64)PAGE_CACHE_SIZE - 1); + last_pos = start_pos + ((u64)num_pages << PAGE_CACHE_SHIFT) - 1; + if (start_pos < inode->i_size) { struct btrfs_ordered_extent *ordered; - lock_extent(&BTRFS_I(inode)->io_tree, - start_pos, last_pos - 1, GFP_NOFS); - ordered = btrfs_lookup_first_ordered_extent(inode, - last_pos - 1); + lock_extent_bits(&BTRFS_I(inode)->io_tree, + start_pos, last_pos, 0, cached_state); + ordered = btrfs_lookup_ordered_range(inode, start_pos, + last_pos - start_pos + 1); if (ordered && ordered->file_offset + ordered->len > start_pos && - ordered->file_offset < last_pos) { - btrfs_put_ordered_extent(ordered); - unlock_extent(&BTRFS_I(inode)->io_tree, - start_pos, last_pos - 1, GFP_NOFS); + ordered->file_offset <= last_pos) { + unlock_extent_cached(&BTRFS_I(inode)->io_tree, + start_pos, last_pos, + cached_state, GFP_NOFS); for (i = 0; i < num_pages; i++) { unlock_page(pages[i]); page_cache_release(pages[i]); } - btrfs_wait_ordered_range(inode, start_pos, - last_pos - start_pos); - goto again; + btrfs_start_ordered_extent(inode, ordered, 1); + btrfs_put_ordered_extent(ordered); + return -EAGAIN; } if (ordered) btrfs_put_ordered_extent(ordered); - clear_extent_bits(&BTRFS_I(inode)->io_tree, start_pos, - last_pos - 1, EXTENT_DIRTY | EXTENT_DELALLOC | - EXTENT_DO_ACCOUNTING, - GFP_NOFS); - unlock_extent(&BTRFS_I(inode)->io_tree, - start_pos, last_pos - 1, GFP_NOFS); + clear_extent_bit(&BTRFS_I(inode)->io_tree, start_pos, + last_pos, EXTENT_DIRTY | EXTENT_DELALLOC | + EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, + 0, 0, cached_state, GFP_NOFS); + *lockstart = start_pos; + *lockend = last_pos; + ret = 1; } + for (i = 0; i < num_pages; i++) { - clear_page_dirty_for_io(pages[i]); + if (clear_page_dirty_for_io(pages[i])) + account_page_redirty(pages[i]); set_page_extent_mapped(pages[i]); WARN_ON(!PageLocked(pages[i])); } - return 0; + + return ret; } -static ssize_t btrfs_file_write(struct file *file, const char __user *buf, - size_t count, loff_t *ppos) +static noinline int check_can_nocow(struct inode *inode, loff_t pos, + size_t *write_bytes) { - loff_t pos; - loff_t start_pos; - ssize_t num_written = 0; - ssize_t err = 0; - int ret = 0; - struct inode *inode = fdentry(file)->d_inode; struct btrfs_root *root = BTRFS_I(inode)->root; - struct page **pages = NULL; - int nrptrs; - struct page *pinned[2]; - unsigned long first_index; - unsigned long last_index; - int will_write; + struct btrfs_ordered_extent *ordered; + u64 lockstart, lockend; + u64 num_bytes; + int ret; - will_write = ((file->f_flags & O_DSYNC) || IS_SYNC(inode) || - (file->f_flags & O_DIRECT)); + ret = btrfs_start_nocow_write(root); + if (!ret) + return -ENOSPC; - nrptrs = min((count + PAGE_CACHE_SIZE - 1) / PAGE_CACHE_SIZE, - PAGE_CACHE_SIZE / (sizeof(struct page *))); - pinned[0] = NULL; - pinned[1] = NULL; + lockstart = round_down(pos, root->sectorsize); + lockend = round_up(pos + *write_bytes, root->sectorsize) - 1; - pos = *ppos; - start_pos = pos; + while (1) { + lock_extent(&BTRFS_I(inode)->io_tree, lockstart, lockend); + ordered = btrfs_lookup_ordered_range(inode, lockstart, + lockend - lockstart + 1); + if (!ordered) { + break; + } + unlock_extent(&BTRFS_I(inode)->io_tree, lockstart, lockend); + btrfs_start_ordered_extent(inode, ordered, 1); + btrfs_put_ordered_extent(ordered); + } - vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE); + num_bytes = lockend - lockstart + 1; + ret = can_nocow_extent(inode, lockstart, &num_bytes, NULL, NULL, NULL); + if (ret <= 0) { + ret = 0; + btrfs_end_nocow_write(root); + } else { + *write_bytes = min_t(size_t, *write_bytes , + num_bytes - pos + lockstart); + } - /* do the reserve before the mutex lock in case we have to do some - * flushing. We wouldn't deadlock, but this is more polite. - */ - err = btrfs_reserve_metadata_for_delalloc(root, inode, 1); - if (err) - goto out_nolock; + unlock_extent(&BTRFS_I(inode)->io_tree, lockstart, lockend); - mutex_lock(&inode->i_mutex); + return ret; +} - current->backing_dev_info = inode->i_mapping->backing_dev_info; - err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode)); - if (err) - goto out; +static noinline ssize_t __btrfs_buffered_write(struct file *file, + struct iov_iter *i, + loff_t pos) +{ + struct inode *inode = file_inode(file); + struct btrfs_root *root = BTRFS_I(inode)->root; + struct page **pages = NULL; + struct extent_state *cached_state = NULL; + u64 release_bytes = 0; + u64 lockstart; + u64 lockend; + unsigned long first_index; + size_t num_written = 0; + int nrptrs; + int ret = 0; + bool only_release_metadata = false; + bool force_page_uptodate = false; + bool need_unlock; + + nrptrs = min((iov_iter_count(i) + PAGE_CACHE_SIZE - 1) / + PAGE_CACHE_SIZE, PAGE_CACHE_SIZE / + (sizeof(struct page *))); + nrptrs = min(nrptrs, current->nr_dirtied_pause - current->nr_dirtied); + nrptrs = max(nrptrs, 8); + pages = kmalloc(nrptrs * sizeof(struct page *), GFP_KERNEL); + if (!pages) + return -ENOMEM; - if (count == 0) - goto out; + first_index = pos >> PAGE_CACHE_SHIFT; - err = file_remove_suid(file); - if (err) - goto out; + while (iov_iter_count(i) > 0) { + size_t offset = pos & (PAGE_CACHE_SIZE - 1); + size_t write_bytes = min(iov_iter_count(i), + nrptrs * (size_t)PAGE_CACHE_SIZE - + offset); + size_t num_pages = (write_bytes + offset + + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; + size_t reserve_bytes; + size_t dirty_pages; + size_t copied; - file_update_time(file); + WARN_ON(num_pages > nrptrs); - pages = kmalloc(nrptrs * sizeof(struct page *), GFP_KERNEL); + /* + * Fault pages before locking them in prepare_pages + * to avoid recursive lock + */ + if (unlikely(iov_iter_fault_in_readable(i, write_bytes))) { + ret = -EFAULT; + break; + } - /* generic_write_checks can change our pos */ - start_pos = pos; + reserve_bytes = num_pages << PAGE_CACHE_SHIFT; + ret = btrfs_check_data_free_space(inode, reserve_bytes); + if (ret == -ENOSPC && + (BTRFS_I(inode)->flags & (BTRFS_INODE_NODATACOW | + BTRFS_INODE_PREALLOC))) { + ret = check_can_nocow(inode, pos, &write_bytes); + if (ret > 0) { + only_release_metadata = true; + /* + * our prealloc extent may be smaller than + * write_bytes, so scale down. + */ + num_pages = (write_bytes + offset + + PAGE_CACHE_SIZE - 1) >> + PAGE_CACHE_SHIFT; + reserve_bytes = num_pages << PAGE_CACHE_SHIFT; + ret = 0; + } else { + ret = -ENOSPC; + } + } - BTRFS_I(inode)->sequence++; - first_index = pos >> PAGE_CACHE_SHIFT; - last_index = (pos + count) >> PAGE_CACHE_SHIFT; + if (ret) + break; - /* - * there are lots of better ways to do this, but this code - * makes sure the first and last page in the file range are - * up to date and ready for cow - */ - if ((pos & (PAGE_CACHE_SIZE - 1))) { - pinned[0] = grab_cache_page(inode->i_mapping, first_index); - if (!PageUptodate(pinned[0])) { - ret = btrfs_readpage(NULL, pinned[0]); - BUG_ON(ret); - wait_on_page_locked(pinned[0]); - } else { - unlock_page(pinned[0]); + ret = btrfs_delalloc_reserve_metadata(inode, reserve_bytes); + if (ret) { + if (!only_release_metadata) + btrfs_free_reserved_data_space(inode, + reserve_bytes); + else + btrfs_end_nocow_write(root); + break; } - } - if ((pos + count) & (PAGE_CACHE_SIZE - 1)) { - pinned[1] = grab_cache_page(inode->i_mapping, last_index); - if (!PageUptodate(pinned[1])) { - ret = btrfs_readpage(NULL, pinned[1]); - BUG_ON(ret); - wait_on_page_locked(pinned[1]); - } else { - unlock_page(pinned[1]); + + release_bytes = reserve_bytes; + need_unlock = false; +again: + /* + * This is going to setup the pages array with the number of + * pages we want, so we don't really need to worry about the + * contents of pages from loop to loop + */ + ret = prepare_pages(inode, pages, num_pages, + pos, write_bytes, + force_page_uptodate); + if (ret) + break; + + ret = lock_and_cleanup_extent_if_need(inode, pages, num_pages, + pos, &lockstart, &lockend, + &cached_state); + if (ret < 0) { + if (ret == -EAGAIN) + goto again; + break; + } else if (ret > 0) { + need_unlock = true; + ret = 0; } - } - while (count > 0) { - size_t offset = pos & (PAGE_CACHE_SIZE - 1); - size_t write_bytes = min(count, nrptrs * - (size_t)PAGE_CACHE_SIZE - - offset); - size_t num_pages = (write_bytes + PAGE_CACHE_SIZE - 1) >> - PAGE_CACHE_SHIFT; + copied = btrfs_copy_from_user(pos, num_pages, + write_bytes, pages, i); - WARN_ON(num_pages > nrptrs); - memset(pages, 0, sizeof(struct page *) * nrptrs); + /* + * if we have trouble faulting in the pages, fall + * back to one page at a time + */ + if (copied < write_bytes) + nrptrs = 1; - ret = btrfs_check_data_free_space(root, inode, write_bytes); - if (ret) - goto out; + if (copied == 0) { + force_page_uptodate = true; + dirty_pages = 0; + } else { + force_page_uptodate = false; + dirty_pages = (copied + offset + + PAGE_CACHE_SIZE - 1) >> + PAGE_CACHE_SHIFT; + } - ret = prepare_pages(root, file, pages, num_pages, - pos, first_index, last_index, - write_bytes); - if (ret) { - btrfs_free_reserved_data_space(root, inode, - write_bytes); - goto out; + /* + * If we had a short copy we need to release the excess delaloc + * bytes we reserved. We need to increment outstanding_extents + * because btrfs_delalloc_release_space will decrement it, but + * we still have an outstanding extent for the chunk we actually + * managed to copy. + */ + if (num_pages > dirty_pages) { + release_bytes = (num_pages - dirty_pages) << + PAGE_CACHE_SHIFT; + if (copied > 0) { + spin_lock(&BTRFS_I(inode)->lock); + BTRFS_I(inode)->outstanding_extents++; + spin_unlock(&BTRFS_I(inode)->lock); + } + if (only_release_metadata) + btrfs_delalloc_release_metadata(inode, + release_bytes); + else + btrfs_delalloc_release_space(inode, + release_bytes); } - ret = btrfs_copy_from_user(pos, num_pages, - write_bytes, pages, buf); + release_bytes = dirty_pages << PAGE_CACHE_SHIFT; + + if (copied > 0) + ret = btrfs_dirty_pages(root, inode, pages, + dirty_pages, pos, copied, + NULL); + if (need_unlock) + unlock_extent_cached(&BTRFS_I(inode)->io_tree, + lockstart, lockend, &cached_state, + GFP_NOFS); if (ret) { - btrfs_free_reserved_data_space(root, inode, - write_bytes); btrfs_drop_pages(pages, num_pages); - goto out; + break; } - ret = dirty_and_release_pages(NULL, root, file, pages, - num_pages, pos, write_bytes); - btrfs_drop_pages(pages, num_pages); - if (ret) { - btrfs_free_reserved_data_space(root, inode, - write_bytes); - goto out; + release_bytes = 0; + if (only_release_metadata) + btrfs_end_nocow_write(root); + + if (only_release_metadata && copied > 0) { + u64 lockstart = round_down(pos, root->sectorsize); + u64 lockend = lockstart + + (dirty_pages << PAGE_CACHE_SHIFT) - 1; + + set_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, + lockend, EXTENT_NORESERVE, NULL, + NULL, GFP_NOFS); + only_release_metadata = false; } - if (will_write) { - filemap_fdatawrite_range(inode->i_mapping, pos, - pos + write_bytes - 1); + btrfs_drop_pages(pages, num_pages); + + cond_resched(); + + balance_dirty_pages_ratelimited(inode->i_mapping); + if (dirty_pages < (root->leafsize >> PAGE_CACHE_SHIFT) + 1) + btrfs_btree_balance_dirty(root); + + pos += copied; + num_written += copied; + } + + kfree(pages); + + if (release_bytes) { + if (only_release_metadata) { + btrfs_end_nocow_write(root); + btrfs_delalloc_release_metadata(inode, release_bytes); } else { - balance_dirty_pages_ratelimited_nr(inode->i_mapping, - num_pages); - if (num_pages < - (root->leafsize >> PAGE_CACHE_SHIFT) + 1) - btrfs_btree_balance_dirty(root, 1); - btrfs_throttle(root); + btrfs_delalloc_release_space(inode, release_bytes); } + } - buf += write_bytes; - count -= write_bytes; - pos += write_bytes; - num_written += write_bytes; + return num_written ? num_written : ret; +} - cond_resched(); +static ssize_t __btrfs_direct_write(struct kiocb *iocb, + struct iov_iter *from, + loff_t pos) +{ + struct file *file = iocb->ki_filp; + ssize_t written; + ssize_t written_buffered; + loff_t endbyte; + int err; + + written = generic_file_direct_write(iocb, from, pos); + + if (written < 0 || !iov_iter_count(from)) + return written; + + pos += written; + written_buffered = __btrfs_buffered_write(file, from, pos); + if (written_buffered < 0) { + err = written_buffered; + goto out; } + endbyte = pos + written_buffered - 1; + err = filemap_write_and_wait_range(file->f_mapping, pos, endbyte); + if (err) + goto out; + written += written_buffered; + iocb->ki_pos = pos + written_buffered; + invalidate_mapping_pages(file->f_mapping, pos >> PAGE_CACHE_SHIFT, + endbyte >> PAGE_CACHE_SHIFT); out: - mutex_unlock(&inode->i_mutex); - if (ret) - err = ret; - btrfs_unreserve_metadata_for_delalloc(root, inode, 1); + return written ? written : err; +} -out_nolock: - kfree(pages); - if (pinned[0]) - page_cache_release(pinned[0]); - if (pinned[1]) - page_cache_release(pinned[1]); - *ppos = pos; +static void update_time_for_write(struct inode *inode) +{ + struct timespec now; + + if (IS_NOCMTIME(inode)) + return; + + now = current_fs_time(inode->i_sb); + if (!timespec_equal(&inode->i_mtime, &now)) + inode->i_mtime = now; + + if (!timespec_equal(&inode->i_ctime, &now)) + inode->i_ctime = now; + + if (IS_I_VERSION(inode)) + inode_inc_iversion(inode); +} + +static ssize_t btrfs_file_write_iter(struct kiocb *iocb, + struct iov_iter *from) +{ + struct file *file = iocb->ki_filp; + struct inode *inode = file_inode(file); + struct btrfs_root *root = BTRFS_I(inode)->root; + u64 start_pos; + u64 end_pos; + ssize_t num_written = 0; + ssize_t err = 0; + size_t count = iov_iter_count(from); + bool sync = (file->f_flags & O_DSYNC) || IS_SYNC(file->f_mapping->host); + loff_t pos = iocb->ki_pos; + + mutex_lock(&inode->i_mutex); + + current->backing_dev_info = inode->i_mapping->backing_dev_info; + err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode)); + if (err) { + mutex_unlock(&inode->i_mutex); + goto out; + } + + if (count == 0) { + mutex_unlock(&inode->i_mutex); + goto out; + } + + iov_iter_truncate(from, count); + + err = file_remove_suid(file); + if (err) { + mutex_unlock(&inode->i_mutex); + goto out; + } + + /* + * If BTRFS flips readonly due to some impossible error + * (fs_info->fs_state now has BTRFS_SUPER_FLAG_ERROR), + * although we have opened a file as writable, we have + * to stop this write operation to ensure FS consistency. + */ + if (test_bit(BTRFS_FS_STATE_ERROR, &root->fs_info->fs_state)) { + mutex_unlock(&inode->i_mutex); + err = -EROFS; + goto out; + } + + /* + * We reserve space for updating the inode when we reserve space for the + * extent we are going to write, so we will enospc out there. We don't + * need to start yet another transaction to update the inode as we will + * update the inode when we finish writing whatever data we write. + */ + update_time_for_write(inode); + + start_pos = round_down(pos, root->sectorsize); + if (start_pos > i_size_read(inode)) { + /* Expand hole size to cover write data, preventing empty gap */ + end_pos = round_up(pos + count, root->sectorsize); + err = btrfs_cont_expand(inode, i_size_read(inode), end_pos); + if (err) { + mutex_unlock(&inode->i_mutex); + goto out; + } + } + + if (sync) + atomic_inc(&BTRFS_I(inode)->sync_writers); + + if (unlikely(file->f_flags & O_DIRECT)) { + num_written = __btrfs_direct_write(iocb, from, pos); + } else { + num_written = __btrfs_buffered_write(file, from, pos); + if (num_written > 0) + iocb->ki_pos = pos + num_written; + } + + mutex_unlock(&inode->i_mutex); /* * we want to make sure fsync finds this change @@ -929,38 +1816,22 @@ out_nolock: * this will either be one more than the running transaction * or the generation used for the next transaction if there isn't * one running right now. + * + * We also have to set last_sub_trans to the current log transid, + * otherwise subsequent syncs to a file that's been synced in this + * transaction will appear to have already occured. */ BTRFS_I(inode)->last_trans = root->fs_info->generation + 1; - - if (num_written > 0 && will_write) { - struct btrfs_trans_handle *trans; - - err = btrfs_wait_ordered_range(inode, start_pos, num_written); - if (err) + BTRFS_I(inode)->last_sub_trans = root->log_transid; + if (num_written > 0) { + err = generic_write_sync(file, pos, num_written); + if (err < 0) num_written = err; - - if ((file->f_flags & O_DSYNC) || IS_SYNC(inode)) { - trans = btrfs_start_transaction(root, 1); - ret = btrfs_log_dentry_safe(trans, root, - file->f_dentry); - if (ret == 0) { - ret = btrfs_sync_log(trans, root); - if (ret == 0) - btrfs_end_transaction(trans, root); - else - btrfs_commit_transaction(trans, root); - } else if (ret != BTRFS_NO_LOG_SYNC) { - btrfs_commit_transaction(trans, root); - } else { - btrfs_end_transaction(trans, root); - } - } - if (file->f_flags & O_DIRECT) { - invalidate_mapping_pages(inode->i_mapping, - start_pos >> PAGE_CACHE_SHIFT, - (start_pos + num_written - 1) >> PAGE_CACHE_SHIFT); - } } + + if (sync) + atomic_dec(&BTRFS_I(inode)->sync_writers); +out: current->backing_dev_info = NULL; return num_written ? num_written : err; } @@ -973,9 +1844,22 @@ int btrfs_release_file(struct inode *inode, struct file *filp) * flush down new bytes that may have been written if the * application were using truncate to replace a file in place. */ - if (BTRFS_I(inode)->ordered_data_close) { - BTRFS_I(inode)->ordered_data_close = 0; - btrfs_add_ordered_operation(NULL, BTRFS_I(inode)->root, inode); + if (test_and_clear_bit(BTRFS_INODE_ORDERED_DATA_CLOSE, + &BTRFS_I(inode)->runtime_flags)) { + struct btrfs_trans_handle *trans; + struct btrfs_root *root = BTRFS_I(inode)->root; + + /* + * We need to block on a committing transaction to keep us from + * throwing a ordered operation on to the list and causing + * something like sync to deadlock trying to flush out this + * inode. + */ + trans = btrfs_start_transaction(root, 0); + if (IS_ERR(trans)) + return PTR_ERR(trans); + btrfs_add_ordered_operation(trans, BTRFS_I(inode)->root, inode); + btrfs_end_transaction(trans, root); if (inode->i_size > BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT) filemap_flush(inode->i_mapping); } @@ -995,56 +1879,114 @@ int btrfs_release_file(struct inode *inode, struct file *filp) * important optimization for directories because holding the mutex prevents * new operations on the dir while we write to disk. */ -int btrfs_sync_file(struct file *file, struct dentry *dentry, int datasync) +int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync) { + struct dentry *dentry = file->f_path.dentry; struct inode *inode = dentry->d_inode; struct btrfs_root *root = BTRFS_I(inode)->root; - int ret = 0; struct btrfs_trans_handle *trans; + struct btrfs_log_ctx ctx; + int ret = 0; + bool full_sync = 0; + trace_btrfs_sync_file(file, datasync); - /* we wait first, since the writeback may change the inode */ - root->log_batch++; - /* the VFS called filemap_fdatawrite for us */ - btrfs_wait_ordered_range(inode, 0, (u64)-1); - root->log_batch++; + /* + * We write the dirty pages in the range and wait until they complete + * out of the ->i_mutex. If so, we can flush the dirty pages by + * multi-task, and make the performance up. See + * btrfs_wait_ordered_range for an explanation of the ASYNC check. + */ + atomic_inc(&BTRFS_I(inode)->sync_writers); + ret = filemap_fdatawrite_range(inode->i_mapping, start, end); + if (!ret && test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT, + &BTRFS_I(inode)->runtime_flags)) + ret = filemap_fdatawrite_range(inode->i_mapping, start, end); + atomic_dec(&BTRFS_I(inode)->sync_writers); + if (ret) + return ret; + + mutex_lock(&inode->i_mutex); + + /* + * We flush the dirty pages again to avoid some dirty pages in the + * range being left. + */ + atomic_inc(&root->log_batch); + full_sync = test_bit(BTRFS_INODE_NEEDS_FULL_SYNC, + &BTRFS_I(inode)->runtime_flags); + if (full_sync) { + ret = btrfs_wait_ordered_range(inode, start, end - start + 1); + if (ret) { + mutex_unlock(&inode->i_mutex); + goto out; + } + } + atomic_inc(&root->log_batch); /* * check the transaction that last modified this inode * and see if its already been committed */ - if (!BTRFS_I(inode)->last_trans) + if (!BTRFS_I(inode)->last_trans) { + mutex_unlock(&inode->i_mutex); goto out; + } /* * if the last transaction that changed this file was before * the current transaction, we can bail out now without any * syncing */ - mutex_lock(&root->fs_info->trans_mutex); - if (BTRFS_I(inode)->last_trans <= + smp_mb(); + if (btrfs_inode_in_log(inode, root->fs_info->generation) || + BTRFS_I(inode)->last_trans <= root->fs_info->last_trans_committed) { BTRFS_I(inode)->last_trans = 0; - mutex_unlock(&root->fs_info->trans_mutex); + + /* + * We'v had everything committed since the last time we were + * modified so clear this flag in case it was set for whatever + * reason, it's no longer relevant. + */ + clear_bit(BTRFS_INODE_NEEDS_FULL_SYNC, + &BTRFS_I(inode)->runtime_flags); + mutex_unlock(&inode->i_mutex); goto out; } - mutex_unlock(&root->fs_info->trans_mutex); /* * ok we haven't committed the transaction yet, lets do a commit */ - if (file && file->private_data) + if (file->private_data) btrfs_ioctl_trans_end(file); - trans = btrfs_start_transaction(root, 1); - if (!trans) { - ret = -ENOMEM; + /* + * We use start here because we will need to wait on the IO to complete + * in btrfs_sync_log, which could require joining a transaction (for + * example checking cross references in the nocow path). If we use join + * here we could get into a situation where we're waiting on IO to + * happen that is blocked on a transaction trying to commit. With start + * we inc the extwriter counter, so we wait for all extwriters to exit + * before we start blocking join'ers. This comment is to keep somebody + * from thinking they are super smart and changing this to + * btrfs_join_transaction *cough*Josef*cough*. + */ + trans = btrfs_start_transaction(root, 0); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + mutex_unlock(&inode->i_mutex); goto out; } + trans->sync = true; - ret = btrfs_log_dentry_safe(trans, root, dentry); - if (ret < 0) - goto out; + btrfs_init_log_ctx(&ctx); + + ret = btrfs_log_dentry_safe(trans, root, dentry, &ctx); + if (ret < 0) { + /* Fallthrough and commit/free transaction. */ + ret = 1; + } /* we've logged all the items and now have a consistent * version of the file in the log. It is possible that @@ -1056,50 +1998,763 @@ int btrfs_sync_file(struct file *file, struct dentry *dentry, int datasync) * file again, but that will end up using the synchronization * inside btrfs_sync_log to keep things safe. */ - mutex_unlock(&dentry->d_inode->i_mutex); + mutex_unlock(&inode->i_mutex); if (ret != BTRFS_NO_LOG_SYNC) { - if (ret > 0) { - ret = btrfs_commit_transaction(trans, root); - } else { - ret = btrfs_sync_log(trans, root); - if (ret == 0) + if (!ret) { + ret = btrfs_sync_log(trans, root, &ctx); + if (!ret) { ret = btrfs_end_transaction(trans, root); - else - ret = btrfs_commit_transaction(trans, root); + goto out; + } } + if (!full_sync) { + ret = btrfs_wait_ordered_range(inode, start, + end - start + 1); + if (ret) { + btrfs_end_transaction(trans, root); + goto out; + } + } + ret = btrfs_commit_transaction(trans, root); } else { ret = btrfs_end_transaction(trans, root); } - mutex_lock(&dentry->d_inode->i_mutex); out: - return ret > 0 ? EIO : ret; + return ret > 0 ? -EIO : ret; } static const struct vm_operations_struct btrfs_file_vm_ops = { .fault = filemap_fault, + .map_pages = filemap_map_pages, .page_mkwrite = btrfs_page_mkwrite, + .remap_pages = generic_file_remap_pages, }; static int btrfs_file_mmap(struct file *filp, struct vm_area_struct *vma) { - vma->vm_ops = &btrfs_file_vm_ops; + struct address_space *mapping = filp->f_mapping; + + if (!mapping->a_ops->readpage) + return -ENOEXEC; + file_accessed(filp); + vma->vm_ops = &btrfs_file_vm_ops; + + return 0; +} + +static int hole_mergeable(struct inode *inode, struct extent_buffer *leaf, + int slot, u64 start, u64 end) +{ + struct btrfs_file_extent_item *fi; + struct btrfs_key key; + + if (slot < 0 || slot >= btrfs_header_nritems(leaf)) + return 0; + + btrfs_item_key_to_cpu(leaf, &key, slot); + if (key.objectid != btrfs_ino(inode) || + key.type != BTRFS_EXTENT_DATA_KEY) + return 0; + + fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item); + + if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG) + return 0; + + if (btrfs_file_extent_disk_bytenr(leaf, fi)) + return 0; + + if (key.offset == end) + return 1; + if (key.offset + btrfs_file_extent_num_bytes(leaf, fi) == start) + return 1; + return 0; +} + +static int fill_holes(struct btrfs_trans_handle *trans, struct inode *inode, + struct btrfs_path *path, u64 offset, u64 end) +{ + struct btrfs_root *root = BTRFS_I(inode)->root; + struct extent_buffer *leaf; + struct btrfs_file_extent_item *fi; + struct extent_map *hole_em; + struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; + struct btrfs_key key; + int ret; + + if (btrfs_fs_incompat(root->fs_info, NO_HOLES)) + goto out; + + key.objectid = btrfs_ino(inode); + key.type = BTRFS_EXTENT_DATA_KEY; + key.offset = offset; + + ret = btrfs_search_slot(trans, root, &key, path, 0, 1); + if (ret < 0) + return ret; + BUG_ON(!ret); + + leaf = path->nodes[0]; + if (hole_mergeable(inode, leaf, path->slots[0]-1, offset, end)) { + u64 num_bytes; + + path->slots[0]--; + fi = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_file_extent_item); + num_bytes = btrfs_file_extent_num_bytes(leaf, fi) + + end - offset; + btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes); + btrfs_set_file_extent_ram_bytes(leaf, fi, num_bytes); + btrfs_set_file_extent_offset(leaf, fi, 0); + btrfs_mark_buffer_dirty(leaf); + goto out; + } + + if (hole_mergeable(inode, leaf, path->slots[0]+1, offset, end)) { + u64 num_bytes; + + path->slots[0]++; + key.offset = offset; + btrfs_set_item_key_safe(root, path, &key); + fi = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_file_extent_item); + num_bytes = btrfs_file_extent_num_bytes(leaf, fi) + end - + offset; + btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes); + btrfs_set_file_extent_ram_bytes(leaf, fi, num_bytes); + btrfs_set_file_extent_offset(leaf, fi, 0); + btrfs_mark_buffer_dirty(leaf); + goto out; + } + btrfs_release_path(path); + + ret = btrfs_insert_file_extent(trans, root, btrfs_ino(inode), offset, + 0, 0, end - offset, 0, end - offset, + 0, 0, 0); + if (ret) + return ret; + +out: + btrfs_release_path(path); + + hole_em = alloc_extent_map(); + if (!hole_em) { + btrfs_drop_extent_cache(inode, offset, end - 1, 0); + set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, + &BTRFS_I(inode)->runtime_flags); + } else { + hole_em->start = offset; + hole_em->len = end - offset; + hole_em->ram_bytes = hole_em->len; + hole_em->orig_start = offset; + + hole_em->block_start = EXTENT_MAP_HOLE; + hole_em->block_len = 0; + hole_em->orig_block_len = 0; + hole_em->bdev = root->fs_info->fs_devices->latest_bdev; + hole_em->compress_type = BTRFS_COMPRESS_NONE; + hole_em->generation = trans->transid; + + do { + btrfs_drop_extent_cache(inode, offset, end - 1, 0); + write_lock(&em_tree->lock); + ret = add_extent_mapping(em_tree, hole_em, 1); + write_unlock(&em_tree->lock); + } while (ret == -EEXIST); + free_extent_map(hole_em); + if (ret) + set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, + &BTRFS_I(inode)->runtime_flags); + } + return 0; } +/* + * Find a hole extent on given inode and change start/len to the end of hole + * extent.(hole/vacuum extent whose em->start <= start && + * em->start + em->len > start) + * When a hole extent is found, return 1 and modify start/len. + */ +static int find_first_non_hole(struct inode *inode, u64 *start, u64 *len) +{ + struct extent_map *em; + int ret = 0; + + em = btrfs_get_extent(inode, NULL, 0, *start, *len, 0); + if (IS_ERR_OR_NULL(em)) { + if (!em) + ret = -ENOMEM; + else + ret = PTR_ERR(em); + return ret; + } + + /* Hole or vacuum extent(only exists in no-hole mode) */ + if (em->block_start == EXTENT_MAP_HOLE) { + ret = 1; + *len = em->start + em->len > *start + *len ? + 0 : *start + *len - em->start - em->len; + *start = em->start + em->len; + } + free_extent_map(em); + return ret; +} + +static int btrfs_punch_hole(struct inode *inode, loff_t offset, loff_t len) +{ + struct btrfs_root *root = BTRFS_I(inode)->root; + struct extent_state *cached_state = NULL; + struct btrfs_path *path; + struct btrfs_block_rsv *rsv; + struct btrfs_trans_handle *trans; + u64 lockstart; + u64 lockend; + u64 tail_start; + u64 tail_len; + u64 orig_start = offset; + u64 cur_offset; + u64 min_size = btrfs_calc_trunc_metadata_size(root, 1); + u64 drop_end; + int ret = 0; + int err = 0; + int rsv_count; + bool same_page; + bool no_holes = btrfs_fs_incompat(root->fs_info, NO_HOLES); + u64 ino_size; + + ret = btrfs_wait_ordered_range(inode, offset, len); + if (ret) + return ret; + + mutex_lock(&inode->i_mutex); + ino_size = round_up(inode->i_size, PAGE_CACHE_SIZE); + ret = find_first_non_hole(inode, &offset, &len); + if (ret < 0) + goto out_only_mutex; + if (ret && !len) { + /* Already in a large hole */ + ret = 0; + goto out_only_mutex; + } + + lockstart = round_up(offset , BTRFS_I(inode)->root->sectorsize); + lockend = round_down(offset + len, + BTRFS_I(inode)->root->sectorsize) - 1; + same_page = ((offset >> PAGE_CACHE_SHIFT) == + ((offset + len - 1) >> PAGE_CACHE_SHIFT)); + + /* + * We needn't truncate any page which is beyond the end of the file + * because we are sure there is no data there. + */ + /* + * Only do this if we are in the same page and we aren't doing the + * entire page. + */ + if (same_page && len < PAGE_CACHE_SIZE) { + if (offset < ino_size) + ret = btrfs_truncate_page(inode, offset, len, 0); + goto out_only_mutex; + } + + /* zero back part of the first page */ + if (offset < ino_size) { + ret = btrfs_truncate_page(inode, offset, 0, 0); + if (ret) { + mutex_unlock(&inode->i_mutex); + return ret; + } + } + + /* Check the aligned pages after the first unaligned page, + * if offset != orig_start, which means the first unaligned page + * including serveral following pages are already in holes, + * the extra check can be skipped */ + if (offset == orig_start) { + /* after truncate page, check hole again */ + len = offset + len - lockstart; + offset = lockstart; + ret = find_first_non_hole(inode, &offset, &len); + if (ret < 0) + goto out_only_mutex; + if (ret && !len) { + ret = 0; + goto out_only_mutex; + } + lockstart = offset; + } + + /* Check the tail unaligned part is in a hole */ + tail_start = lockend + 1; + tail_len = offset + len - tail_start; + if (tail_len) { + ret = find_first_non_hole(inode, &tail_start, &tail_len); + if (unlikely(ret < 0)) + goto out_only_mutex; + if (!ret) { + /* zero the front end of the last page */ + if (tail_start + tail_len < ino_size) { + ret = btrfs_truncate_page(inode, + tail_start + tail_len, 0, 1); + if (ret) + goto out_only_mutex; + } + } + } + + if (lockend < lockstart) { + mutex_unlock(&inode->i_mutex); + return 0; + } + + while (1) { + struct btrfs_ordered_extent *ordered; + + truncate_pagecache_range(inode, lockstart, lockend); + + lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend, + 0, &cached_state); + ordered = btrfs_lookup_first_ordered_extent(inode, lockend); + + /* + * We need to make sure we have no ordered extents in this range + * and nobody raced in and read a page in this range, if we did + * we need to try again. + */ + if ((!ordered || + (ordered->file_offset + ordered->len <= lockstart || + ordered->file_offset > lockend)) && + !btrfs_page_exists_in_range(inode, lockstart, lockend)) { + if (ordered) + btrfs_put_ordered_extent(ordered); + break; + } + if (ordered) + btrfs_put_ordered_extent(ordered); + unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, + lockend, &cached_state, GFP_NOFS); + ret = btrfs_wait_ordered_range(inode, lockstart, + lockend - lockstart + 1); + if (ret) { + mutex_unlock(&inode->i_mutex); + return ret; + } + } + + path = btrfs_alloc_path(); + if (!path) { + ret = -ENOMEM; + goto out; + } + + rsv = btrfs_alloc_block_rsv(root, BTRFS_BLOCK_RSV_TEMP); + if (!rsv) { + ret = -ENOMEM; + goto out_free; + } + rsv->size = btrfs_calc_trunc_metadata_size(root, 1); + rsv->failfast = 1; + + /* + * 1 - update the inode + * 1 - removing the extents in the range + * 1 - adding the hole extent if no_holes isn't set + */ + rsv_count = no_holes ? 2 : 3; + trans = btrfs_start_transaction(root, rsv_count); + if (IS_ERR(trans)) { + err = PTR_ERR(trans); + goto out_free; + } + + ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv, rsv, + min_size); + BUG_ON(ret); + trans->block_rsv = rsv; + + cur_offset = lockstart; + len = lockend - cur_offset; + while (cur_offset < lockend) { + ret = __btrfs_drop_extents(trans, root, inode, path, + cur_offset, lockend + 1, + &drop_end, 1, 0, 0, NULL); + if (ret != -ENOSPC) + break; + + trans->block_rsv = &root->fs_info->trans_block_rsv; + + if (cur_offset < ino_size) { + ret = fill_holes(trans, inode, path, cur_offset, + drop_end); + if (ret) { + err = ret; + break; + } + } + + cur_offset = drop_end; + + ret = btrfs_update_inode(trans, root, inode); + if (ret) { + err = ret; + break; + } + + btrfs_end_transaction(trans, root); + btrfs_btree_balance_dirty(root); + + trans = btrfs_start_transaction(root, rsv_count); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + trans = NULL; + break; + } + + ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv, + rsv, min_size); + BUG_ON(ret); /* shouldn't happen */ + trans->block_rsv = rsv; + + ret = find_first_non_hole(inode, &cur_offset, &len); + if (unlikely(ret < 0)) + break; + if (ret && !len) { + ret = 0; + break; + } + } + + if (ret) { + err = ret; + goto out_trans; + } + + trans->block_rsv = &root->fs_info->trans_block_rsv; + /* + * Don't insert file hole extent item if it's for a range beyond eof + * (because it's useless) or if it represents a 0 bytes range (when + * cur_offset == drop_end). + */ + if (cur_offset < ino_size && cur_offset < drop_end) { + ret = fill_holes(trans, inode, path, cur_offset, drop_end); + if (ret) { + err = ret; + goto out_trans; + } + } + +out_trans: + if (!trans) + goto out_free; + + inode_inc_iversion(inode); + inode->i_mtime = inode->i_ctime = CURRENT_TIME; + + trans->block_rsv = &root->fs_info->trans_block_rsv; + ret = btrfs_update_inode(trans, root, inode); + btrfs_end_transaction(trans, root); + btrfs_btree_balance_dirty(root); +out_free: + btrfs_free_path(path); + btrfs_free_block_rsv(root, rsv); +out: + unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend, + &cached_state, GFP_NOFS); +out_only_mutex: + mutex_unlock(&inode->i_mutex); + if (ret && !err) + err = ret; + return err; +} + +static long btrfs_fallocate(struct file *file, int mode, + loff_t offset, loff_t len) +{ + struct inode *inode = file_inode(file); + struct extent_state *cached_state = NULL; + struct btrfs_root *root = BTRFS_I(inode)->root; + u64 cur_offset; + u64 last_byte; + u64 alloc_start; + u64 alloc_end; + u64 alloc_hint = 0; + u64 locked_end; + struct extent_map *em; + int blocksize = BTRFS_I(inode)->root->sectorsize; + int ret; + + alloc_start = round_down(offset, blocksize); + alloc_end = round_up(offset + len, blocksize); + + /* Make sure we aren't being give some crap mode */ + if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE)) + return -EOPNOTSUPP; + + if (mode & FALLOC_FL_PUNCH_HOLE) + return btrfs_punch_hole(inode, offset, len); + + /* + * Make sure we have enough space before we do the + * allocation. + */ + ret = btrfs_check_data_free_space(inode, alloc_end - alloc_start); + if (ret) + return ret; + if (root->fs_info->quota_enabled) { + ret = btrfs_qgroup_reserve(root, alloc_end - alloc_start); + if (ret) + goto out_reserve_fail; + } + + mutex_lock(&inode->i_mutex); + ret = inode_newsize_ok(inode, alloc_end); + if (ret) + goto out; + + if (alloc_start > inode->i_size) { + ret = btrfs_cont_expand(inode, i_size_read(inode), + alloc_start); + if (ret) + goto out; + } else { + /* + * If we are fallocating from the end of the file onward we + * need to zero out the end of the page if i_size lands in the + * middle of a page. + */ + ret = btrfs_truncate_page(inode, inode->i_size, 0, 0); + if (ret) + goto out; + } + + /* + * wait for ordered IO before we have any locks. We'll loop again + * below with the locks held. + */ + ret = btrfs_wait_ordered_range(inode, alloc_start, + alloc_end - alloc_start); + if (ret) + goto out; + + locked_end = alloc_end - 1; + while (1) { + struct btrfs_ordered_extent *ordered; + + /* the extent lock is ordered inside the running + * transaction + */ + lock_extent_bits(&BTRFS_I(inode)->io_tree, alloc_start, + locked_end, 0, &cached_state); + ordered = btrfs_lookup_first_ordered_extent(inode, + alloc_end - 1); + if (ordered && + ordered->file_offset + ordered->len > alloc_start && + ordered->file_offset < alloc_end) { + btrfs_put_ordered_extent(ordered); + unlock_extent_cached(&BTRFS_I(inode)->io_tree, + alloc_start, locked_end, + &cached_state, GFP_NOFS); + /* + * we can't wait on the range with the transaction + * running or with the extent lock held + */ + ret = btrfs_wait_ordered_range(inode, alloc_start, + alloc_end - alloc_start); + if (ret) + goto out; + } else { + if (ordered) + btrfs_put_ordered_extent(ordered); + break; + } + } + + cur_offset = alloc_start; + while (1) { + u64 actual_end; + + em = btrfs_get_extent(inode, NULL, 0, cur_offset, + alloc_end - cur_offset, 0); + if (IS_ERR_OR_NULL(em)) { + if (!em) + ret = -ENOMEM; + else + ret = PTR_ERR(em); + break; + } + last_byte = min(extent_map_end(em), alloc_end); + actual_end = min_t(u64, extent_map_end(em), offset + len); + last_byte = ALIGN(last_byte, blocksize); + + if (em->block_start == EXTENT_MAP_HOLE || + (cur_offset >= inode->i_size && + !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) { + ret = btrfs_prealloc_file_range(inode, mode, cur_offset, + last_byte - cur_offset, + 1 << inode->i_blkbits, + offset + len, + &alloc_hint); + + if (ret < 0) { + 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); + + cur_offset = last_byte; + if (cur_offset >= alloc_end) { + ret = 0; + break; + } + } + unlock_extent_cached(&BTRFS_I(inode)->io_tree, alloc_start, locked_end, + &cached_state, GFP_NOFS); +out: + mutex_unlock(&inode->i_mutex); + if (root->fs_info->quota_enabled) + btrfs_qgroup_free(root, alloc_end - alloc_start); +out_reserve_fail: + /* Let go of our reservation. */ + btrfs_free_reserved_data_space(inode, alloc_end - alloc_start); + return ret; +} + +static int find_desired_extent(struct inode *inode, loff_t *offset, int whence) +{ + struct btrfs_root *root = BTRFS_I(inode)->root; + struct extent_map *em = NULL; + struct extent_state *cached_state = NULL; + u64 lockstart = *offset; + u64 lockend = i_size_read(inode); + u64 start = *offset; + u64 len = i_size_read(inode); + int ret = 0; + + lockend = max_t(u64, root->sectorsize, lockend); + if (lockend <= lockstart) + lockend = lockstart + root->sectorsize; + + lockend--; + len = lockend - lockstart + 1; + + len = max_t(u64, len, root->sectorsize); + if (inode->i_size == 0) + return -ENXIO; + + lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend, 0, + &cached_state); + + while (start < inode->i_size) { + em = btrfs_get_extent_fiemap(inode, NULL, 0, start, len, 0); + if (IS_ERR(em)) { + ret = PTR_ERR(em); + em = NULL; + break; + } + + if (whence == SEEK_HOLE && + (em->block_start == EXTENT_MAP_HOLE || + test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) + break; + else if (whence == SEEK_DATA && + (em->block_start != EXTENT_MAP_HOLE && + !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) + break; + + start = em->start + em->len; + free_extent_map(em); + em = NULL; + cond_resched(); + } + free_extent_map(em); + if (!ret) { + if (whence == SEEK_DATA && start >= inode->i_size) + ret = -ENXIO; + else + *offset = min_t(loff_t, start, inode->i_size); + } + unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend, + &cached_state, GFP_NOFS); + return ret; +} + +static loff_t btrfs_file_llseek(struct file *file, loff_t offset, int whence) +{ + struct inode *inode = file->f_mapping->host; + int ret; + + mutex_lock(&inode->i_mutex); + switch (whence) { + case SEEK_END: + case SEEK_CUR: + offset = generic_file_llseek(file, offset, whence); + goto out; + case SEEK_DATA: + case SEEK_HOLE: + if (offset >= i_size_read(inode)) { + mutex_unlock(&inode->i_mutex); + return -ENXIO; + } + + ret = find_desired_extent(inode, &offset, whence); + if (ret) { + mutex_unlock(&inode->i_mutex); + return ret; + } + } + + offset = vfs_setpos(file, offset, inode->i_sb->s_maxbytes); +out: + mutex_unlock(&inode->i_mutex); + return offset; +} + const struct file_operations btrfs_file_operations = { - .llseek = generic_file_llseek, - .read = do_sync_read, - .aio_read = generic_file_aio_read, + .llseek = btrfs_file_llseek, + .read = new_sync_read, + .write = new_sync_write, + .read_iter = generic_file_read_iter, .splice_read = generic_file_splice_read, - .write = btrfs_file_write, + .write_iter = btrfs_file_write_iter, .mmap = btrfs_file_mmap, .open = generic_file_open, .release = btrfs_release_file, .fsync = btrfs_sync_file, + .fallocate = btrfs_fallocate, .unlocked_ioctl = btrfs_ioctl, #ifdef CONFIG_COMPAT .compat_ioctl = btrfs_ioctl, #endif }; + +void btrfs_auto_defrag_exit(void) +{ + if (btrfs_inode_defrag_cachep) + kmem_cache_destroy(btrfs_inode_defrag_cachep); +} + +int btrfs_auto_defrag_init(void) +{ + btrfs_inode_defrag_cachep = kmem_cache_create("btrfs_inode_defrag", + sizeof(struct inode_defrag), 0, + SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, + NULL); + if (!btrfs_inode_defrag_cachep) + return -ENOMEM; + + return 0; +} |