diff options
Diffstat (limited to 'fs/btrfs/extent_map.c')
| -rw-r--r-- | fs/btrfs/extent_map.c | 3119 |
1 files changed, 84 insertions, 3035 deletions
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c index 010a287fbd7..268ad8facf6 100644 --- a/fs/btrfs/extent_map.c +++ b/fs/btrfs/extent_map.c @@ -1,17 +1,10 @@ -#include <linux/bitops.h> -#include <linux/slab.h> -#include <linux/bio.h> -#include <linux/mm.h> +#include <linux/err.h> #include <linux/gfp.h> -#include <linux/pagemap.h> -#include <linux/page-flags.h> +#include <linux/slab.h> #include <linux/module.h> #include <linux/spinlock.h> -#include <linux/blkdev.h> -#include <linux/swap.h> #include <linux/version.h> -#include <linux/writeback.h> -#include <linux/pagevec.h> +#include <linux/hardirq.h> #include "extent_map.h" /* temporary define until extent_map moves out of btrfs */ @@ -21,27 +14,6 @@ struct kmem_cache *btrfs_cache_create(const char *name, size_t size, unsigned long)); static struct kmem_cache *extent_map_cache; -static struct kmem_cache *extent_state_cache; -static struct kmem_cache *extent_buffer_cache; - -static LIST_HEAD(buffers); -static LIST_HEAD(states); - -static spinlock_t state_lock = SPIN_LOCK_UNLOCKED; -#define BUFFER_LRU_MAX 64 - -struct tree_entry { - u64 start; - u64 end; - int in_tree; - struct rb_node rb_node; -}; - -struct extent_page_data { - struct bio *bio; - struct extent_map_tree *tree; - get_extent_t *get_extent; -}; int __init extent_map_init(void) { @@ -50,72 +22,23 @@ int __init extent_map_init(void) NULL); if (!extent_map_cache) return -ENOMEM; - extent_state_cache = btrfs_cache_create("extent_state", - sizeof(struct extent_state), 0, - NULL); - if (!extent_state_cache) - goto free_map_cache; - extent_buffer_cache = btrfs_cache_create("extent_buffers", - sizeof(struct extent_buffer), 0, - NULL); - if (!extent_buffer_cache) - goto free_state_cache; return 0; - -free_state_cache: - kmem_cache_destroy(extent_state_cache); -free_map_cache: - kmem_cache_destroy(extent_map_cache); - return -ENOMEM; } void extent_map_exit(void) { - struct extent_state *state; - - while (!list_empty(&states)) { - state = list_entry(states.next, struct extent_state, list); - printk("state leak: start %Lu end %Lu state %lu in tree %d refs %d\n", state->start, state->end, state->state, state->in_tree, atomic_read(&state->refs)); - list_del(&state->list); - kmem_cache_free(extent_state_cache, state); - - } - if (extent_map_cache) kmem_cache_destroy(extent_map_cache); - if (extent_state_cache) - kmem_cache_destroy(extent_state_cache); - if (extent_buffer_cache) - kmem_cache_destroy(extent_buffer_cache); } -void extent_map_tree_init(struct extent_map_tree *tree, - struct address_space *mapping, gfp_t mask) +void extent_map_tree_init(struct extent_map_tree *tree, gfp_t mask) { tree->map.rb_node = NULL; - tree->state.rb_node = NULL; - tree->ops = NULL; - tree->dirty_bytes = 0; - rwlock_init(&tree->lock); - spin_lock_init(&tree->lru_lock); - tree->mapping = mapping; - INIT_LIST_HEAD(&tree->buffer_lru); - tree->lru_size = 0; + tree->last = NULL; + spin_lock_init(&tree->lock); } EXPORT_SYMBOL(extent_map_tree_init); -void extent_map_tree_empty_lru(struct extent_map_tree *tree) -{ - struct extent_buffer *eb; - while(!list_empty(&tree->buffer_lru)) { - eb = list_entry(tree->buffer_lru.next, struct extent_buffer, - lru); - list_del_init(&eb->lru); - free_extent_buffer(eb); - } -} -EXPORT_SYMBOL(extent_map_tree_empty_lru); - struct extent_map *alloc_extent_map(gfp_t mask) { struct extent_map *em; @@ -123,6 +46,7 @@ struct extent_map *alloc_extent_map(gfp_t mask) if (!em || IS_ERR(em)) return em; em->in_tree = 0; + em->flags = 0; atomic_set(&em->refs, 1); return em; } @@ -132,6 +56,7 @@ void free_extent_map(struct extent_map *em) { if (!em) return; + WARN_ON(atomic_read(&em->refs) == 0); if (atomic_dec_and_test(&em->refs)) { WARN_ON(em->in_tree); kmem_cache_free(extent_map_cache, em); @@ -139,64 +64,28 @@ void free_extent_map(struct extent_map *em) } EXPORT_SYMBOL(free_extent_map); - -struct extent_state *alloc_extent_state(gfp_t mask) -{ - struct extent_state *state; - unsigned long flags; - - state = kmem_cache_alloc(extent_state_cache, mask); - if (!state || IS_ERR(state)) - return state; - state->state = 0; - state->in_tree = 0; - state->private = 0; - - spin_lock_irqsave(&state_lock, flags); - list_add(&state->list, &states); - spin_unlock_irqrestore(&state_lock, flags); - - atomic_set(&state->refs, 1); - init_waitqueue_head(&state->wq); - return state; -} -EXPORT_SYMBOL(alloc_extent_state); - -void free_extent_state(struct extent_state *state) -{ - unsigned long flags; - if (!state) - return; - if (atomic_dec_and_test(&state->refs)) { - WARN_ON(state->in_tree); - spin_lock_irqsave(&state_lock, flags); - list_del(&state->list); - spin_unlock_irqrestore(&state_lock, flags); - kmem_cache_free(extent_state_cache, state); - } -} -EXPORT_SYMBOL(free_extent_state); - static struct rb_node *tree_insert(struct rb_root *root, u64 offset, struct rb_node *node) { struct rb_node ** p = &root->rb_node; struct rb_node * parent = NULL; - struct tree_entry *entry; + struct extent_map *entry; while(*p) { parent = *p; - entry = rb_entry(parent, struct tree_entry, rb_node); + entry = rb_entry(parent, struct extent_map, rb_node); + + WARN_ON(!entry->in_tree); if (offset < entry->start) p = &(*p)->rb_left; - else if (offset > entry->end) + else if (offset >= extent_map_end(entry)) p = &(*p)->rb_right; else return parent; } - entry = rb_entry(node, struct tree_entry, rb_node); + entry = rb_entry(node, struct extent_map, rb_node); entry->in_tree = 1; rb_link_node(node, parent, p); rb_insert_color(node, root); @@ -210,17 +99,19 @@ static struct rb_node *__tree_search(struct rb_root *root, u64 offset, struct rb_node * n = root->rb_node; struct rb_node *prev = NULL; struct rb_node *orig_prev = NULL; - struct tree_entry *entry; - struct tree_entry *prev_entry = NULL; + struct extent_map *entry; + struct extent_map *prev_entry = NULL; while(n) { - entry = rb_entry(n, struct tree_entry, rb_node); + entry = rb_entry(n, struct extent_map, rb_node); prev = n; prev_entry = entry; + WARN_ON(!entry->in_tree); + if (offset < entry->start) n = n->rb_left; - else if (offset > entry->end) + else if (offset >= extent_map_end(entry)) n = n->rb_right; else return n; @@ -228,19 +119,19 @@ static struct rb_node *__tree_search(struct rb_root *root, u64 offset, if (prev_ret) { orig_prev = prev; - while(prev && offset > prev_entry->end) { + while(prev && offset >= extent_map_end(prev_entry)) { prev = rb_next(prev); - prev_entry = rb_entry(prev, struct tree_entry, rb_node); + prev_entry = rb_entry(prev, struct extent_map, rb_node); } *prev_ret = prev; prev = orig_prev; } if (next_ret) { - prev_entry = rb_entry(prev, struct tree_entry, rb_node); + prev_entry = rb_entry(prev, struct extent_map, rb_node); while(prev && offset < prev_entry->start) { prev = rb_prev(prev); - prev_entry = rb_entry(prev, struct tree_entry, rb_node); + prev_entry = rb_entry(prev, struct extent_map, rb_node); } *next_ret = prev; } @@ -257,22 +148,26 @@ static inline struct rb_node *tree_search(struct rb_root *root, u64 offset) return ret; } -static int tree_delete(struct rb_root *root, u64 offset) +static int mergable_maps(struct extent_map *prev, struct extent_map *next) { - struct rb_node *node; - struct tree_entry *entry; - - node = __tree_search(root, offset, NULL, NULL); - if (!node) - return -ENOENT; - entry = rb_entry(node, struct tree_entry, rb_node); - entry->in_tree = 0; - rb_erase(node, root); + if (extent_map_end(prev) == next->start && + prev->flags == next->flags && + prev->bdev == next->bdev && + ((next->block_start == EXTENT_MAP_HOLE && + prev->block_start == EXTENT_MAP_HOLE) || + (next->block_start == EXTENT_MAP_INLINE && + prev->block_start == EXTENT_MAP_INLINE) || + (next->block_start == EXTENT_MAP_DELALLOC && + prev->block_start == EXTENT_MAP_DELALLOC) || + (next->block_start < EXTENT_MAP_LAST_BYTE - 1 && + next->block_start == extent_map_block_end(prev)))) { + return 1; + } return 0; } /* - * add_extent_mapping tries a simple backward merge with existing + * add_extent_mapping tries a simple forward/backward merge with existing * mappings. The extent_map struct passed in will be inserted into * the tree directly (no copies made, just a reference taken). */ @@ -280,13 +175,12 @@ int add_extent_mapping(struct extent_map_tree *tree, struct extent_map *em) { int ret = 0; - struct extent_map *prev = NULL; + struct extent_map *merge = NULL; struct rb_node *rb; - write_lock_irq(&tree->lock); - rb = tree_insert(&tree->map, em->end, &em->rb_node); + rb = tree_insert(&tree->map, em->start, &em->rb_node); if (rb) { - prev = rb_entry(rb, struct extent_map, rb_node); + merge = rb_entry(rb, struct extent_map, rb_node); ret = -EEXIST; goto out; } @@ -294,53 +188,60 @@ int add_extent_mapping(struct extent_map_tree *tree, if (em->start != 0) { rb = rb_prev(&em->rb_node); if (rb) - prev = rb_entry(rb, struct extent_map, rb_node); - if (prev && prev->end + 1 == em->start && - ((em->block_start == EXTENT_MAP_HOLE && - prev->block_start == EXTENT_MAP_HOLE) || - (em->block_start == EXTENT_MAP_INLINE && - prev->block_start == EXTENT_MAP_INLINE) || - (em->block_start == EXTENT_MAP_DELALLOC && - prev->block_start == EXTENT_MAP_DELALLOC) || - (em->block_start < EXTENT_MAP_DELALLOC - 1 && - em->block_start == prev->block_end + 1))) { - em->start = prev->start; - em->block_start = prev->block_start; - rb_erase(&prev->rb_node, &tree->map); - prev->in_tree = 0; - free_extent_map(prev); + merge = rb_entry(rb, struct extent_map, rb_node); + if (rb && mergable_maps(merge, em)) { + em->start = merge->start; + em->len += merge->len; + em->block_start = merge->block_start; + merge->in_tree = 0; + rb_erase(&merge->rb_node, &tree->map); + free_extent_map(merge); } } + rb = rb_next(&em->rb_node); + if (rb) + merge = rb_entry(rb, struct extent_map, rb_node); + if (rb && mergable_maps(em, merge)) { + em->len += merge->len; + rb_erase(&merge->rb_node, &tree->map); + merge->in_tree = 0; + free_extent_map(merge); + } + tree->last = em; out: - write_unlock_irq(&tree->lock); return ret; } EXPORT_SYMBOL(add_extent_mapping); +static u64 range_end(u64 start, u64 len) +{ + if (start + len < start) + return (u64)-1; + return start + len; +} + /* * lookup_extent_mapping returns the first extent_map struct in the - * tree that intersects the [start, end] (inclusive) range. There may + * tree that intersects the [start, len] range. There may * be additional objects in the tree that intersect, so check the object * returned carefully to make sure you don't need additional lookups. */ struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree, - u64 start, u64 end) + u64 start, u64 len) { struct extent_map *em; struct rb_node *rb_node; - struct rb_node *prev = NULL; - struct rb_node *next = NULL; + struct rb_node *prev = NULL; struct rb_node *next = NULL; u64 end = range_end(start, len); em = tree->last; if (em && end > em->start && start < extent_map_end(em)) goto found; - read_lock_irq(&tree->lock); rb_node = __tree_search(&tree->map, start, &prev, &next); if (!rb_node && prev) { em = rb_entry(prev, struct extent_map, rb_node); - if (em->start <= end && em->end >= start) + if (end > em->start && start < extent_map_end(em)) goto found; } if (!rb_node && next) { em = rb_entry(next, struct extent_map, rb_node); - if (em->start <= end && em->end >= start) + if (end > em->start && start < extent_map_end(em)) goto found; } if (!rb_node) { @@ -352,14 +253,16 @@ struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree, goto out; } em = rb_entry(rb_node, struct extent_map, rb_node); - if (em->end < start || em->start > end) { - em = NULL; - goto out; - } + if (end > em->start && start < extent_map_end(em)) + goto found; + + em = NULL; + goto out; + found: atomic_inc(&em->refs); + tree->last = em; out: - read_unlock_irq(&tree->lock); return em; } EXPORT_SYMBOL(lookup_extent_mapping); @@ -370,2866 +273,12 @@ EXPORT_SYMBOL(lookup_extent_mapping); */ int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em) { - int ret; - - write_lock_irq(&tree->lock); - ret = tree_delete(&tree->map, em->end); - write_unlock_irq(&tree->lock); - return ret; -} -EXPORT_SYMBOL(remove_extent_mapping); - -/* - * utility function to look for merge candidates inside a given range. - * Any extents with matching state are merged together into a single - * extent in the tree. Extents with EXTENT_IO in their state field - * are not merged because the end_io handlers need to be able to do - * operations on them without sleeping (or doing allocations/splits). - * - * This should be called with the tree lock held. - */ -static int merge_state(struct extent_map_tree *tree, - struct extent_state *state) -{ - struct extent_state *other; - struct rb_node *other_node; - - if (state->state & EXTENT_IOBITS) - return 0; - - other_node = rb_prev(&state->rb_node); - if (other_node) { - other = rb_entry(other_node, struct extent_state, rb_node); - if (other->end == state->start - 1 && - other->state == state->state) { - state->start = other->start; - other->in_tree = 0; - rb_erase(&other->rb_node, &tree->state); - free_extent_state(other); - } - } - other_node = rb_next(&state->rb_node); - if (other_node) { - other = rb_entry(other_node, struct extent_state, rb_node); - if (other->start == state->end + 1 && - other->state == state->state) { - other->start = state->start; - state->in_tree = 0; - rb_erase(&state->rb_node, &tree->state); - free_extent_state(state); - } - } - return 0; -} - -/* - * insert an extent_state struct into the tree. 'bits' are set on the - * struct before it is inserted. - * - * This may return -EEXIST if the extent is already there, in which case the - * state struct is freed. - * - * The tree lock is not taken internally. This is a utility function and - * probably isn't what you want to call (see set/clear_extent_bit). - */ -static int insert_state(struct extent_map_tree *tree, - struct extent_state *state, u64 start, u64 end, - int bits) -{ - struct rb_node *node; - - if (end < start) { - printk("end < start %Lu %Lu\n", end, start); - WARN_ON(1); - } - if (bits & EXTENT_DIRTY) - tree->dirty_bytes += end - start + 1; - state->state |= bits; - state->start = start; - state->end = end; - node = tree_insert(&tree->state, end, &state->rb_node); - if (node) { - struct extent_state *found; - found = rb_entry(node, struct extent_state, rb_node); - printk("found node %Lu %Lu on insert of %Lu %Lu\n", found->start, found->end, start, end); - free_extent_state(state); - return -EEXIST; - } - merge_state(tree, state); - return 0; -} - -/* - * split a given extent state struct in two, inserting the preallocated - * struct 'prealloc' as the newly created second half. 'split' indicates an - * offset inside 'orig' where it should be split. - * - * Before calling, - * the tree has 'orig' at [orig->start, orig->end]. After calling, there - * are two extent state structs in the tree: - * prealloc: [orig->start, split - 1] - * orig: [ split, orig->end ] - * - * The tree locks are not taken by this function. They need to be held - * by the caller. - */ -static int split_state(struct extent_map_tree *tree, struct extent_state *orig, - struct extent_state *prealloc, u64 split) -{ - struct rb_node *node; - prealloc->start = orig->start; - prealloc->end = split - 1; - prealloc->state = orig->state; - orig->start = split; - - node = tree_insert(&tree->state, prealloc->end, &prealloc->rb_node); - if (node) { - struct extent_state *found; - found = rb_entry(node, struct extent_state, rb_node); - printk("found node %Lu %Lu on insert of %Lu %Lu\n", found->start, found->end, prealloc->start, prealloc->end); - free_extent_state(prealloc); - return -EEXIST; - } - return 0; -} - -/* - * utility function to clear some bits in an extent state struct. - * it will optionally wake up any one waiting on this state (wake == 1), or - * forcibly remove the state from the tree (delete == 1). - * - * If no bits are set on the state struct after clearing things, the - * struct is freed and removed from the tree - */ -static int clear_state_bit(struct extent_map_tree *tree, - struct extent_state *state, int bits, int wake, - int delete) -{ - int ret = state->state & bits; - - if ((bits & EXTENT_DIRTY) && (state->state & EXTENT_DIRTY)) { - u64 range = state->end - state->start + 1; - WARN_ON(range > tree->dirty_bytes); - tree->dirty_bytes -= range; - } - state->state &= ~bits; - if (wake) - wake_up(&state->wq); - if (delete || state->state == 0) { - if (state->in_tree) { - rb_erase(&state->rb_node, &tree->state); - state->in_tree = 0; - free_extent_state(state); - } else { - WARN_ON(1); - } - } else { - merge_state(tree, state); - } - return ret; -} - -/* - * clear some bits on a range in the tree. This may require splitting - * or inserting elements in the tree, so the gfp mask is used to - * indicate which allocations or sleeping are allowed. - * - * pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove - * the given range from the tree regardless of state (ie for truncate). - * - * the range [start, end] is inclusive. - * - * This takes the tree lock, and returns < 0 on error, > 0 if any of the - * bits were already set, or zero if none of the bits were already set. - */ -int clear_extent_bit(struct extent_map_tree *tree, u64 start, u64 end, - int bits, int wake, int delete, gfp_t mask) -{ - struct extent_state *state; - struct extent_state *prealloc = NULL; - struct rb_node *node; - unsigned long flags; - int err; - int set = 0; - -again: - if (!prealloc && (mask & __GFP_WAIT)) { - prealloc = alloc_extent_state(mask); - if (!prealloc) - return -ENOMEM; - } - - write_lock_irqsave(&tree->lock, flags); - /* - * this search will find the extents that end after - * our range starts - */ - node = tree_search(&tree->state, start); - if (!node) - goto out; - state = rb_entry(node, struct extent_state, rb_node); - if (state->start > end) - goto out; - WARN_ON(state->end < start); - - /* - * | ---- desired range ---- | - * | state | or - * | ------------- state -------------- | - * - * We need to split the extent we found, and may flip - * bits on second half. - * - * If the extent we found extends past our range, we - * just split and search again. It'll get split again - * the next time though. - * - * If the extent we found is inside our range, we clear - * the desired bit on it. - */ - - if (state->start < start) { - err = split_state(tree, state, prealloc, start); - BUG_ON(err == -EEXIST); - prealloc = NULL; - if (err) - goto out; - if (state->end <= end) { - start = state->end + 1; - set |= clear_state_bit(tree, state, bits, - wake, delete); - } else { - start = state->start; - } - goto search_again; - } - /* - * | ---- desired range ---- | - * | state | - * We need to split the extent, and clear the bit - * on the first half - */ - if (state->start <= end && state->end > end) { - err = split_state(tree, state, prealloc, end + 1); - BUG_ON(err == -EEXIST); - - if (wake) - wake_up(&state->wq); - set |= clear_state_bit(tree, prealloc, bits, - wake, delete); - prealloc = NULL; - goto out; - } - - start = state->end + 1; - set |= clear_state_bit(tree, state, bits, wake, delete); - goto search_again; - -out: - write_unlock_irqrestore(&tree->lock, flags); - if (prealloc) - free_extent_state(prealloc); - - return set; - -search_again: - if (start > end) - goto out; - write_unlock_irqrestore(&tree->lock, flags); - if (mask & __GFP_WAIT) - cond_resched(); - goto again; -} -EXPORT_SYMBOL(clear_extent_bit); - -static int wait_on_state(struct extent_map_tree *tree, - struct extent_state *state) -{ - DEFINE_WAIT(wait); - prepare_to_wait(&state->wq, &wait, TASK_UNINTERRUPTIBLE); - read_unlock_irq(&tree->lock); - schedule(); - read_lock_irq(&tree->lock); - finish_wait(&state->wq, &wait); - return 0; -} - -/* - * waits for one or more bits to clear on a range in the state tree. - * The range [start, end] is inclusive. - * The tree lock is taken by this function - */ -int wait_extent_bit(struct extent_map_tree *tree, u64 start, u64 end, int bits) -{ - struct extent_state *state; - struct rb_node *node; - - read_lock_irq(&tree->lock); -again: - while (1) { - /* - * this search will find all the extents that end after - * our range starts - */ - node = tree_search(&tree->state, start); - if (!node) - break; - - state = rb_entry(node, struct extent_state, rb_node); - - if (state->start > end) - goto out; - - if (state->state & bits) { - start = state->start; - atomic_inc(&state->refs); - wait_on_state(tree, state); - free_extent_state(state); - goto again; - } - start = state->end + 1; - - if (start > end) - break; - - if (need_resched()) { - read_unlock_irq(&tree->lock); - cond_resched(); - read_lock_irq(&tree->lock); - } - } -out: - read_unlock_irq(&tree->lock); - return 0; -} -EXPORT_SYMBOL(wait_extent_bit); - -static void set_state_bits(struct extent_map_tree *tree, - struct extent_state *state, - int bits) -{ - if ((bits & EXTENT_DIRTY) && !(state->state & EXTENT_DIRTY)) { - u64 range = state->end - state->start + 1; - tree->dirty_bytes += range; - } - state->state |= bits; -} - -/* - * set some bits on a range in the tree. This may require allocations - * or sleeping, so the gfp mask is used to indicate what is allowed. - * - * If 'exclusive' == 1, this will fail with -EEXIST if some part of the - * range already has the desired bits set. The start of the existing - * range is returned in failed_start in this case. - * - * [start, end] is inclusive - * This takes the tree lock. - */ -int set_extent_bit(struct extent_map_tree *tree, u64 start, u64 end, int bits, - int exclusive, u64 *failed_start, gfp_t mask) -{ - struct extent_state *state; - struct extent_state *prealloc = NULL; - struct rb_node *node; - unsigned long flags; - int err = 0; - int set; - u64 last_start; - u64 last_end; -again: - if (!prealloc && (mask & __GFP_WAIT)) { - prealloc = alloc_extent_state(mask); - if (!prealloc) - return -ENOMEM; - } - - write_lock_irqsave(&tree->lock, flags); - /* - * this search will find all the extents that end after - * our range starts. - */ - node = tree_search(&tree->state, start); - if (!node) { - err = insert_state(tree, prealloc, start, end, bits); - prealloc = NULL; - BUG_ON(err == -EEXIST); - goto out; - } - - state = rb_entry(node, struct extent_state, rb_node); - last_start = state->start; - last_end = state->end; - - /* - * | ---- desired range ---- | - * | state | - * - * Just lock what we found and keep going - */ - if (state->start == start && state->end <= end) { - set = state->state & bits; - if (set && exclusive) { - *failed_start = state->start; - err = -EEXIST; - goto out; - } - set_state_bits(tree, state, bits); - start = state->end + 1; - merge_state(tree, state); - goto search_again; - } - - /* - * | ---- desired range ---- | - * | state | - * or - * | ------------- state -------------- | - * - * We need to split the extent we found, and may flip bits on - * second half. - * - * If the extent we found extends past our - * range, we just split and search again. It'll get split - * again the next time though. - * - * If the extent we found is inside our range, we set the - * desired bit on it. - */ - if (state->start < start) { - set = state->state & bits; - if (exclusive && set) { - *failed_start = start; - err = -EEXIST; - goto out; - } - err = split_state(tree, state, prealloc, start); - BUG_ON(err == -EEXIST); - prealloc = NULL; - if (err) - goto out; - if (state->end <= end) { - set_state_bits(tree, state, bits); - start = state->end + 1; - merge_state(tree, state); - } else { - start = state->start; - } - goto search_again; - } - /* - * | ---- desired range ---- | - * | state | or | state | - * - * There's a hole, we need to insert something in it and - * ignore the extent we found. - */ - if (state->start > start) { - u64 this_end; - if (end < last_start) - this_end = end; - else - this_end = last_start -1; - err = insert_state(tree, prealloc, start, this_end, - bits); - prealloc = NULL; - BUG_ON(err == -EEXIST); - if (err) - goto out; - start = this_end + 1; - goto search_again; - } - /* - * | ---- desired range ---- | - * | state | - * We need to split the extent, and set the bit - * on the first half - */ - if (state->start <= end && state->end > end) { - set = state->state & bits; - if (exclusive && set) { - *failed_start = start; - err = -EEXIST; - goto out; - } - err = split_state(tree, state, prealloc, end + 1); - BUG_ON(err == -EEXIST); - - set_state_bits(tree, prealloc, bits); - merge_state(tree, prealloc); - prealloc = NULL; - goto out; - } - - goto search_again; - -out: - write_unlock_irqrestore(&tree->lock, flags); - if (prealloc) - free_extent_state(prealloc); - - return err; - -search_again: - if (start > end) - goto out; - write_unlock_irqrestore(&tree->lock, flags); - if (mask & __GFP_WAIT) - cond_resched(); - goto again; -} -EXPORT_SYMBOL(set_extent_bit); - -/* wrappers around set/clear extent bit */ -int set_extent_dirty(struct extent_map_tree *tree, u64 start, u64 end, - gfp_t mask) -{ - return set_extent_bit(tree, start, end, EXTENT_DIRTY, 0, NULL, - mask); -} -EXPORT_SYMBOL(set_extent_dirty); - -int set_extent_bits(struct extent_map_tree *tree, u64 start, u64 end, - int bits, gfp_t mask) -{ - return set_extent_bit(tree, start, end, bits, 0, NULL, - mask); -} -EXPORT_SYMBOL(set_extent_bits); - -int clear_extent_bits(struct extent_map_tree *tree, u64 start, u64 end, - int bits, gfp_t mask) -{ - return clear_extent_bit(tree, start, end, bits, 0, 0, mask); -} -EXPORT_SYMBOL(clear_extent_bits); - -int set_extent_delalloc(struct extent_map_tree *tree, u64 start, u64 end, - gfp_t mask) -{ - return set_extent_bit(tree, start, end, - EXTENT_DELALLOC | EXTENT_DIRTY, 0, NULL, - mask); -} -EXPORT_SYMBOL(set_extent_delalloc); - -int clear_extent_dirty(struct extent_map_tree *tree, u64 start, u64 end, - gfp_t mask) -{ - return clear_extent_bit(tree, start, end, - EXTENT_DIRTY | EXTENT_DELALLOC, 0, 0, mask); -} -EXPORT_SYMBOL(clear_extent_dirty); - -int set_extent_new(struct extent_map_tree *tree, u64 start, u64 end, - gfp_t mask) -{ - return set_extent_bit(tree, start, end, EXTENT_NEW, 0, NULL, - mask); -} -EXPORT_SYMBOL(set_extent_new); - -int clear_extent_new(struct extent_map_tree *tree, u64 start, u64 end, - gfp_t mask) -{ - return clear_extent_bit(tree, start, end, EXTENT_NEW, 0, 0, mask); -} -EXPORT_SYMBOL(clear_extent_new); - -int set_extent_uptodate(struct extent_map_tree *tree, u64 start, u64 end, - gfp_t mask) -{ - return set_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, NULL, - mask); -} -EXPORT_SYMBOL(set_extent_uptodate); - -int clear_extent_uptodate(struct extent_map_tree *tree, u64 start, u64 end, - gfp_t mask) -{ - return clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0, mask); -} -EXPORT_SYMBOL(clear_extent_uptodate); - -int set_extent_writeback(struct extent_map_tree *tree, u64 start, u64 end, - gfp_t mask) -{ - return set_extent_bit(tree, start, end, EXTENT_WRITEBACK, - 0, NULL, mask); -} -EXPORT_SYMBOL(set_extent_writeback); - -int clear_extent_writeback(struct extent_map_tree *tree, u64 start, u64 end, - gfp_t mask) -{ - return clear_extent_bit(tree, start, end, EXTENT_WRITEBACK, 1, 0, mask); -} -EXPORT_SYMBOL(clear_extent_writeback); - -int wait_on_extent_writeback(struct extent_map_tree *tree, u64 start, u64 end) -{ - return wait_extent_bit(tree, start, end, EXTENT_WRITEBACK); -} -EXPORT_SYMBOL(wait_on_extent_writeback); - -/* - * locks a range in ascending order, waiting for any locked regions - * it hits on the way. [start,end] are inclusive, and this will sleep. - */ -int lock_extent(struct extent_map_tree *tree, u64 start, u64 end, gfp_t mask) -{ - int err; - u64 failed_start; - while (1) { - err = set_extent_bit(tree, start, end, EXTENT_LOCKED, 1, - &failed_start, mask); - if (err == -EEXIST && (mask & __GFP_WAIT)) { - wait_extent_bit(tree, failed_start, end, EXTENT_LOCKED); - start = failed_start; - } else { - break; - } - WARN_ON(start > end); - } - return err; -} -EXPORT_SYMBOL(lock_extent); - -int unlock_extent(struct extent_map_tree *tree, u64 start, u64 end, - gfp_t mask) -{ - return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, mask); -} -EXPORT_SYMBOL(unlock_extent); - -/* - * helper function to set pages and extents in the tree dirty - */ -int set_range_dirty(struct extent_map_tree *tree, u64 start, u64 end) -{ - unsigned long index = start >> PAGE_CACHE_SHIFT; - unsigned long end_index = end >> PAGE_CACHE_SHIFT; - struct page *page; - - while (index <= end_index) { - page = find_get_page(tree->mapping, index); - BUG_ON(!page); - __set_page_dirty_nobuffers(page); - page_cache_release(page); - index++; - } - set_extent_dirty(tree, start, end, GFP_NOFS); - return 0; -} -EXPORT_SYMBOL(set_range_dirty); - -/* - * helper function to set both pages and extents in the tree writeback - */ -int set_range_writeback(struct extent_map_tree *tree, u64 start, u64 end) -{ - unsigned long index = start >> PAGE_CACHE_SHIFT; - unsigned long end_index = end >> PAGE_CACHE_SHIFT; - struct page *page; - - while (index <= end_index) { - page = find_get_page(tree->mapping, index); - BUG_ON(!page); - set_page_writeback(page); - page_cache_release(page); - index++; - } - set_extent_writeback(tree, start, end, GFP_NOFS); - return 0; -} -EXPORT_SYMBOL(set_range_writeback); - -int find_first_extent_bit(struct extent_map_tree *tree, u64 start, - u64 *start_ret, u64 *end_ret, int bits) -{ - struct rb_node *node; - struct extent_state *state; - int ret = 1; - - read_lock_irq(&tree->lock); - /* - * this search will find all the extents that end after - * our range starts. - */ - node = tree_search(&tree->state, start); - if (!node || IS_ERR(node)) { - goto out; - } - - while(1) { - state = rb_entry(node, struct extent_state, rb_node); - if (state->end >= start && (state->state & bits)) { - *start_ret = state->start; - *end_ret = state->end; - ret = 0; - break; - } - node = rb_next(node); - if (!node) - break; - } -out: - read_unlock_irq(&tree->lock); - return ret; -} -EXPORT_SYMBOL(find_first_extent_bit); - -u64 find_lock_delalloc_range(struct extent_map_tree *tree, - u64 *start, u64 *end, u64 max_bytes) -{ - struct rb_node *node; - struct extent_state *state; - u64 cur_start = *start; - u64 found = 0; - u64 total_bytes = 0; - - write_lock_irq(&tree->lock); - /* - * this search will find all the extents that end after - * our range starts. - */ -search_again: - node = tree_search(&tree->state, cur_start); - if (!node || IS_ERR(node)) { - *end = (u64)-1; - goto out; - } - - while(1) { - state = rb_entry(node, struct extent_state, rb_node); - if (found && state->start != cur_start) { - goto out; - } - if (!(state->state & EXTENT_DELALLOC)) { - if (!found) - *end = state->end; - goto out; - } - if (!found) { - struct extent_state *prev_state; - struct rb_node *prev_node = node; - while(1) { - prev_node = rb_prev(prev_node); - if (!prev_node) - break; - prev_state = rb_entry(prev_node, - struct extent_state, - rb_node); - if (!(prev_state->state & EXTENT_DELALLOC)) - break; - state = prev_state; - node = prev_node; - } - } |