/fs/btrfs/extent_io.c
C | 4300 lines | 3703 code | 578 blank | 19 comment | 749 complexity | 713a1225fd840aed76eb7dba1f1e4e2c MD5 | raw file
Possible License(s): GPL-2.0
- #include <linux/bitops.h>
- #include <linux/slab.h>
- #include <linux/bio.h>
- #include <linux/mm.h>
- #include <linux/pagemap.h>
- #include <linux/page-flags.h>
- #include <linux/module.h>
- #include <linux/spinlock.h>
- #include <linux/blkdev.h>
- #include <linux/swap.h>
- #include <linux/writeback.h>
- #include <linux/pagevec.h>
- #include <linux/prefetch.h>
- #include <linux/cleancache.h>
- #include "extent_io.h"
- #include "extent_map.h"
- #include "compat.h"
- #include "ctree.h"
- #include "btrfs_inode.h"
- #include "volumes.h"
- #include "check-integrity.h"
- #include "locking.h"
- static struct kmem_cache *extent_state_cache;
- static struct kmem_cache *extent_buffer_cache;
- static LIST_HEAD(buffers);
- static LIST_HEAD(states);
- #define LEAK_DEBUG 0
- #if LEAK_DEBUG
- static DEFINE_SPINLOCK(leak_lock);
- #endif
- #define BUFFER_LRU_MAX 64
- struct tree_entry {
- u64 start;
- u64 end;
- struct rb_node rb_node;
- };
- struct extent_page_data {
- struct bio *bio;
- struct extent_io_tree *tree;
- get_extent_t *get_extent;
- unsigned int extent_locked:1;
-
- unsigned int sync_io:1;
- };
- static noinline void flush_write_bio(void *data);
- static inline struct btrfs_fs_info *
- tree_fs_info(struct extent_io_tree *tree)
- {
- return btrfs_sb(tree->mapping->host->i_sb);
- }
- int __init extent_io_init(void)
- {
- extent_state_cache = kmem_cache_create("extent_state",
- sizeof(struct extent_state), 0,
- SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
- if (!extent_state_cache)
- return -ENOMEM;
- extent_buffer_cache = kmem_cache_create("extent_buffers",
- sizeof(struct extent_buffer), 0,
- SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL);
- if (!extent_buffer_cache)
- goto free_state_cache;
- return 0;
- free_state_cache:
- kmem_cache_destroy(extent_state_cache);
- return -ENOMEM;
- }
- void extent_io_exit(void)
- {
- struct extent_state *state;
- struct extent_buffer *eb;
- while (!list_empty(&states)) {
- state = list_entry(states.next, struct extent_state, leak_list);
- printk(KERN_ERR "btrfs state leak: start %llu end %llu "
- "state %lu in tree %p refs %d\n",
- (unsigned long long)state->start,
- (unsigned long long)state->end,
- state->state, state->tree, atomic_read(&state->refs));
- list_del(&state->leak_list);
- kmem_cache_free(extent_state_cache, state);
- }
- while (!list_empty(&buffers)) {
- eb = list_entry(buffers.next, struct extent_buffer, leak_list);
- printk(KERN_ERR "btrfs buffer leak start %llu len %lu "
- "refs %d\n", (unsigned long long)eb->start,
- eb->len, atomic_read(&eb->refs));
- list_del(&eb->leak_list);
- kmem_cache_free(extent_buffer_cache, eb);
- }
- if (extent_state_cache)
- kmem_cache_destroy(extent_state_cache);
- if (extent_buffer_cache)
- kmem_cache_destroy(extent_buffer_cache);
- }
- void extent_io_tree_init(struct extent_io_tree *tree,
- struct address_space *mapping)
- {
- tree->state = RB_ROOT;
- INIT_RADIX_TREE(&tree->buffer, GFP_ATOMIC);
- tree->ops = NULL;
- tree->dirty_bytes = 0;
- spin_lock_init(&tree->lock);
- spin_lock_init(&tree->buffer_lock);
- tree->mapping = mapping;
- }
- static struct extent_state *alloc_extent_state(gfp_t mask)
- {
- struct extent_state *state;
- #if LEAK_DEBUG
- unsigned long flags;
- #endif
- state = kmem_cache_alloc(extent_state_cache, mask);
- if (!state)
- return state;
- state->state = 0;
- state->private = 0;
- state->tree = NULL;
- #if LEAK_DEBUG
- spin_lock_irqsave(&leak_lock, flags);
- list_add(&state->leak_list, &states);
- spin_unlock_irqrestore(&leak_lock, flags);
- #endif
- atomic_set(&state->refs, 1);
- init_waitqueue_head(&state->wq);
- trace_alloc_extent_state(state, mask, _RET_IP_);
- return state;
- }
- void free_extent_state(struct extent_state *state)
- {
- if (!state)
- return;
- if (atomic_dec_and_test(&state->refs)) {
- #if LEAK_DEBUG
- unsigned long flags;
- #endif
- WARN_ON(state->tree);
- #if LEAK_DEBUG
- spin_lock_irqsave(&leak_lock, flags);
- list_del(&state->leak_list);
- spin_unlock_irqrestore(&leak_lock, flags);
- #endif
- trace_free_extent_state(state, _RET_IP_);
- kmem_cache_free(extent_state_cache, 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;
- while (*p) {
- parent = *p;
- entry = rb_entry(parent, struct tree_entry, rb_node);
- if (offset < entry->start)
- p = &(*p)->rb_left;
- else if (offset > entry->end)
- p = &(*p)->rb_right;
- else
- return parent;
- }
- entry = rb_entry(node, struct tree_entry, rb_node);
- rb_link_node(node, parent, p);
- rb_insert_color(node, root);
- return NULL;
- }
- static struct rb_node *__etree_search(struct extent_io_tree *tree, u64 offset,
- struct rb_node **prev_ret,
- struct rb_node **next_ret)
- {
- struct rb_root *root = &tree->state;
- 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;
- while (n) {
- entry = rb_entry(n, struct tree_entry, rb_node);
- prev = n;
- prev_entry = entry;
- if (offset < entry->start)
- n = n->rb_left;
- else if (offset > entry->end)
- n = n->rb_right;
- else
- return n;
- }
- if (prev_ret) {
- orig_prev = prev;
- while (prev && offset > prev_entry->end) {
- prev = rb_next(prev);
- prev_entry = rb_entry(prev, struct tree_entry, rb_node);
- }
- *prev_ret = prev;
- prev = orig_prev;
- }
- if (next_ret) {
- prev_entry = rb_entry(prev, struct tree_entry, rb_node);
- while (prev && offset < prev_entry->start) {
- prev = rb_prev(prev);
- prev_entry = rb_entry(prev, struct tree_entry, rb_node);
- }
- *next_ret = prev;
- }
- return NULL;
- }
- static inline struct rb_node *tree_search(struct extent_io_tree *tree,
- u64 offset)
- {
- struct rb_node *prev = NULL;
- struct rb_node *ret;
- ret = __etree_search(tree, offset, &prev, NULL);
- if (!ret)
- return prev;
- return ret;
- }
- static void merge_cb(struct extent_io_tree *tree, struct extent_state *new,
- struct extent_state *other)
- {
- if (tree->ops && tree->ops->merge_extent_hook)
- tree->ops->merge_extent_hook(tree->mapping->host, new,
- other);
- }
- static void merge_state(struct extent_io_tree *tree,
- struct extent_state *state)
- {
- struct extent_state *other;
- struct rb_node *other_node;
- if (state->state & (EXTENT_IOBITS | EXTENT_BOUNDARY))
- return;
- 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) {
- merge_cb(tree, state, other);
- state->start = other->start;
- other->tree = NULL;
- 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) {
- merge_cb(tree, state, other);
- state->end = other->end;
- other->tree = NULL;
- rb_erase(&other->rb_node, &tree->state);
- free_extent_state(other);
- }
- }
- }
- static void set_state_cb(struct extent_io_tree *tree,
- struct extent_state *state, int *bits)
- {
- if (tree->ops && tree->ops->set_bit_hook)
- tree->ops->set_bit_hook(tree->mapping->host, state, bits);
- }
- static void clear_state_cb(struct extent_io_tree *tree,
- struct extent_state *state, int *bits)
- {
- if (tree->ops && tree->ops->clear_bit_hook)
- tree->ops->clear_bit_hook(tree->mapping->host, state, bits);
- }
- static void set_state_bits(struct extent_io_tree *tree,
- struct extent_state *state, int *bits);
- static int insert_state(struct extent_io_tree *tree,
- struct extent_state *state, u64 start, u64 end,
- int *bits)
- {
- struct rb_node *node;
- if (end < start) {
- printk(KERN_ERR "btrfs end < start %llu %llu\n",
- (unsigned long long)end,
- (unsigned long long)start);
- WARN_ON(1);
- }
- state->start = start;
- state->end = end;
- set_state_bits(tree, state, bits);
- 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(KERN_ERR "btrfs found node %llu %llu on insert of "
- "%llu %llu\n", (unsigned long long)found->start,
- (unsigned long long)found->end,
- (unsigned long long)start, (unsigned long long)end);
- return -EEXIST;
- }
- state->tree = tree;
- merge_state(tree, state);
- return 0;
- }
- static void split_cb(struct extent_io_tree *tree, struct extent_state *orig,
- u64 split)
- {
- if (tree->ops && tree->ops->split_extent_hook)
- tree->ops->split_extent_hook(tree->mapping->host, orig, split);
- }
- static int split_state(struct extent_io_tree *tree, struct extent_state *orig,
- struct extent_state *prealloc, u64 split)
- {
- struct rb_node *node;
- split_cb(tree, orig, split);
- 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) {
- free_extent_state(prealloc);
- return -EEXIST;
- }
- prealloc->tree = tree;
- return 0;
- }
- static struct extent_state *next_state(struct extent_state *state)
- {
- struct rb_node *next = rb_next(&state->rb_node);
- if (next)
- return rb_entry(next, struct extent_state, rb_node);
- else
- return NULL;
- }
- static struct extent_state *clear_state_bit(struct extent_io_tree *tree,
- struct extent_state *state,
- int *bits, int wake)
- {
- struct extent_state *next;
- int bits_to_clear = *bits & ~EXTENT_CTLBITS;
- if ((bits_to_clear & EXTENT_DIRTY) && (state->state & EXTENT_DIRTY)) {
- u64 range = state->end - state->start + 1;
- WARN_ON(range > tree->dirty_bytes);
- tree->dirty_bytes -= range;
- }
- clear_state_cb(tree, state, bits);
- state->state &= ~bits_to_clear;
- if (wake)
- wake_up(&state->wq);
- if (state->state == 0) {
- next = next_state(state);
- if (state->tree) {
- rb_erase(&state->rb_node, &tree->state);
- state->tree = NULL;
- free_extent_state(state);
- } else {
- WARN_ON(1);
- }
- } else {
- merge_state(tree, state);
- next = next_state(state);
- }
- return next;
- }
- static struct extent_state *
- alloc_extent_state_atomic(struct extent_state *prealloc)
- {
- if (!prealloc)
- prealloc = alloc_extent_state(GFP_ATOMIC);
- return prealloc;
- }
- void extent_io_tree_panic(struct extent_io_tree *tree, int err)
- {
- btrfs_panic(tree_fs_info(tree), err, "Locking error: "
- "Extent tree was modified by another "
- "thread while locked.");
- }
- int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
- int bits, int wake, int delete,
- struct extent_state **cached_state,
- gfp_t mask)
- {
- struct extent_state *state;
- struct extent_state *cached;
- struct extent_state *prealloc = NULL;
- struct rb_node *node;
- u64 last_end;
- int err;
- int clear = 0;
- if (delete)
- bits |= ~EXTENT_CTLBITS;
- bits |= EXTENT_FIRST_DELALLOC;
- if (bits & (EXTENT_IOBITS | EXTENT_BOUNDARY))
- clear = 1;
- again:
- if (!prealloc && (mask & __GFP_WAIT)) {
- prealloc = alloc_extent_state(mask);
- if (!prealloc)
- return -ENOMEM;
- }
- spin_lock(&tree->lock);
- if (cached_state) {
- cached = *cached_state;
- if (clear) {
- *cached_state = NULL;
- cached_state = NULL;
- }
- if (cached && cached->tree && cached->start <= start &&
- cached->end > start) {
- if (clear)
- atomic_dec(&cached->refs);
- state = cached;
- goto hit_next;
- }
- if (clear)
- free_extent_state(cached);
- }
- node = tree_search(tree, start);
- if (!node)
- goto out;
- state = rb_entry(node, struct extent_state, rb_node);
- hit_next:
- if (state->start > end)
- goto out;
- WARN_ON(state->end < start);
- last_end = state->end;
-
- if (!(state->state & bits)) {
- state = next_state(state);
- goto next;
- }
- if (state->start < start) {
- prealloc = alloc_extent_state_atomic(prealloc);
- BUG_ON(!prealloc);
- err = split_state(tree, state, prealloc, start);
- if (err)
- extent_io_tree_panic(tree, err);
- prealloc = NULL;
- if (err)
- goto out;
- if (state->end <= end) {
- clear_state_bit(tree, state, &bits, wake);
- if (last_end == (u64)-1)
- goto out;
- start = last_end + 1;
- }
- goto search_again;
- }
- if (state->start <= end && state->end > end) {
- prealloc = alloc_extent_state_atomic(prealloc);
- BUG_ON(!prealloc);
- err = split_state(tree, state, prealloc, end + 1);
- if (err)
- extent_io_tree_panic(tree, err);
- if (wake)
- wake_up(&state->wq);
- clear_state_bit(tree, prealloc, &bits, wake);
- prealloc = NULL;
- goto out;
- }
- state = clear_state_bit(tree, state, &bits, wake);
- next:
- if (last_end == (u64)-1)
- goto out;
- start = last_end + 1;
- if (start <= end && state && !need_resched())
- goto hit_next;
- goto search_again;
- out:
- spin_unlock(&tree->lock);
- if (prealloc)
- free_extent_state(prealloc);
- return 0;
- search_again:
- if (start > end)
- goto out;
- spin_unlock(&tree->lock);
- if (mask & __GFP_WAIT)
- cond_resched();
- goto again;
- }
- static void wait_on_state(struct extent_io_tree *tree,
- struct extent_state *state)
- __releases(tree->lock)
- __acquires(tree->lock)
- {
- DEFINE_WAIT(wait);
- prepare_to_wait(&state->wq, &wait, TASK_UNINTERRUPTIBLE);
- spin_unlock(&tree->lock);
- schedule();
- spin_lock(&tree->lock);
- finish_wait(&state->wq, &wait);
- }
- void wait_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, int bits)
- {
- struct extent_state *state;
- struct rb_node *node;
- spin_lock(&tree->lock);
- again:
- while (1) {
- node = tree_search(tree, 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;
- cond_resched_lock(&tree->lock);
- }
- out:
- spin_unlock(&tree->lock);
- }
- static void set_state_bits(struct extent_io_tree *tree,
- struct extent_state *state,
- int *bits)
- {
- int bits_to_set = *bits & ~EXTENT_CTLBITS;
- set_state_cb(tree, state, bits);
- if ((bits_to_set & EXTENT_DIRTY) && !(state->state & EXTENT_DIRTY)) {
- u64 range = state->end - state->start + 1;
- tree->dirty_bytes += range;
- }
- state->state |= bits_to_set;
- }
- static void cache_state(struct extent_state *state,
- struct extent_state **cached_ptr)
- {
- if (cached_ptr && !(*cached_ptr)) {
- if (state->state & (EXTENT_IOBITS | EXTENT_BOUNDARY)) {
- *cached_ptr = state;
- atomic_inc(&state->refs);
- }
- }
- }
- static void uncache_state(struct extent_state **cached_ptr)
- {
- if (cached_ptr && (*cached_ptr)) {
- struct extent_state *state = *cached_ptr;
- *cached_ptr = NULL;
- free_extent_state(state);
- }
- }
- static int __must_check
- __set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
- int bits, int exclusive_bits, u64 *failed_start,
- struct extent_state **cached_state, gfp_t mask)
- {
- struct extent_state *state;
- struct extent_state *prealloc = NULL;
- struct rb_node *node;
- int err = 0;
- u64 last_start;
- u64 last_end;
- bits |= EXTENT_FIRST_DELALLOC;
- again:
- if (!prealloc && (mask & __GFP_WAIT)) {
- prealloc = alloc_extent_state(mask);
- BUG_ON(!prealloc);
- }
- spin_lock(&tree->lock);
- if (cached_state && *cached_state) {
- state = *cached_state;
- if (state->start <= start && state->end > start &&
- state->tree) {
- node = &state->rb_node;
- goto hit_next;
- }
- }
- node = tree_search(tree, start);
- if (!node) {
- prealloc = alloc_extent_state_atomic(prealloc);
- BUG_ON(!prealloc);
- err = insert_state(tree, prealloc, start, end, &bits);
- if (err)
- extent_io_tree_panic(tree, err);
- prealloc = NULL;
- goto out;
- }
- state = rb_entry(node, struct extent_state, rb_node);
- hit_next:
- last_start = state->start;
- last_end = state->end;
- if (state->start == start && state->end <= end) {
- struct rb_node *next_node;
- if (state->state & exclusive_bits) {
- *failed_start = state->start;
- err = -EEXIST;
- goto out;
- }
- set_state_bits(tree, state, &bits);
- cache_state(state, cached_state);
- merge_state(tree, state);
- if (last_end == (u64)-1)
- goto out;
- start = last_end + 1;
- next_node = rb_next(&state->rb_node);
- if (next_node && start < end && prealloc && !need_resched()) {
- state = rb_entry(next_node, struct extent_state,
- rb_node);
- if (state->start == start)
- goto hit_next;
- }
- goto search_again;
- }
- if (state->start < start) {
- if (state->state & exclusive_bits) {
- *failed_start = start;
- err = -EEXIST;
- goto out;
- }
- prealloc = alloc_extent_state_atomic(prealloc);
- BUG_ON(!prealloc);
- err = split_state(tree, state, prealloc, start);
- if (err)
- extent_io_tree_panic(tree, err);
- prealloc = NULL;
- if (err)
- goto out;
- if (state->end <= end) {
- set_state_bits(tree, state, &bits);
- cache_state(state, cached_state);
- merge_state(tree, state);
- if (last_end == (u64)-1)
- goto out;
- start = last_end + 1;
- }
- goto search_again;
- }
- if (state->start > start) {
- u64 this_end;
- if (end < last_start)
- this_end = end;
- else
- this_end = last_start - 1;
- prealloc = alloc_extent_state_atomic(prealloc);
- BUG_ON(!prealloc);
- err = insert_state(tree, prealloc, start, this_end,
- &bits);
- if (err)
- extent_io_tree_panic(tree, err);
- cache_state(prealloc, cached_state);
- prealloc = NULL;
- start = this_end + 1;
- goto search_again;
- }
- if (state->start <= end && state->end > end) {
- if (state->state & exclusive_bits) {
- *failed_start = start;
- err = -EEXIST;
- goto out;
- }
- prealloc = alloc_extent_state_atomic(prealloc);
- BUG_ON(!prealloc);
- err = split_state(tree, state, prealloc, end + 1);
- if (err)
- extent_io_tree_panic(tree, err);
- set_state_bits(tree, prealloc, &bits);
- cache_state(prealloc, cached_state);
- merge_state(tree, prealloc);
- prealloc = NULL;
- goto out;
- }
- goto search_again;
- out:
- spin_unlock(&tree->lock);
- if (prealloc)
- free_extent_state(prealloc);
- return err;
- search_again:
- if (start > end)
- goto out;
- spin_unlock(&tree->lock);
- if (mask & __GFP_WAIT)
- cond_resched();
- goto again;
- }
- int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, int bits,
- u64 *failed_start, struct extent_state **cached_state,
- gfp_t mask)
- {
- return __set_extent_bit(tree, start, end, bits, 0, failed_start,
- cached_state, mask);
- }
- int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
- int bits, int clear_bits, gfp_t mask)
- {
- struct extent_state *state;
- struct extent_state *prealloc = NULL;
- struct rb_node *node;
- int err = 0;
- u64 last_start;
- u64 last_end;
- again:
- if (!prealloc && (mask & __GFP_WAIT)) {
- prealloc = alloc_extent_state(mask);
- if (!prealloc)
- return -ENOMEM;
- }
- spin_lock(&tree->lock);
- node = tree_search(tree, start);
- if (!node) {
- prealloc = alloc_extent_state_atomic(prealloc);
- if (!prealloc) {
- err = -ENOMEM;
- goto out;
- }
- err = insert_state(tree, prealloc, start, end, &bits);
- prealloc = NULL;
- if (err)
- extent_io_tree_panic(tree, err);
- goto out;
- }
- state = rb_entry(node, struct extent_state, rb_node);
- hit_next:
- last_start = state->start;
- last_end = state->end;
- if (state->start == start && state->end <= end) {
- struct rb_node *next_node;
- set_state_bits(tree, state, &bits);
- clear_state_bit(tree, state, &clear_bits, 0);
- if (last_end == (u64)-1)
- goto out;
- start = last_end + 1;
- next_node = rb_next(&state->rb_node);
- if (next_node && start < end && prealloc && !need_resched()) {
- state = rb_entry(next_node, struct extent_state,
- rb_node);
- if (state->start == start)
- goto hit_next;
- }
- goto search_again;
- }
- if (state->start < start) {
- prealloc = alloc_extent_state_atomic(prealloc);
- if (!prealloc) {
- err = -ENOMEM;
- goto out;
- }
- err = split_state(tree, state, prealloc, start);
- if (err)
- extent_io_tree_panic(tree, err);
- prealloc = NULL;
- if (err)
- goto out;
- if (state->end <= end) {
- set_state_bits(tree, state, &bits);
- clear_state_bit(tree, state, &clear_bits, 0);
- if (last_end == (u64)-1)
- goto out;
- start = last_end + 1;
- }
- goto search_again;
- }
- if (state->start > start) {
- u64 this_end;
- if (end < last_start)
- this_end = end;
- else
- this_end = last_start - 1;
- prealloc = alloc_extent_state_atomic(prealloc);
- if (!prealloc) {
- err = -ENOMEM;
- goto out;
- }
- err = insert_state(tree, prealloc, start, this_end,
- &bits);
- if (err)
- extent_io_tree_panic(tree, err);
- prealloc = NULL;
- start = this_end + 1;
- goto search_again;
- }
- if (state->start <= end && state->end > end) {
- prealloc = alloc_extent_state_atomic(prealloc);
- if (!prealloc) {
- err = -ENOMEM;
- goto out;
- }
- err = split_state(tree, state, prealloc, end + 1);
- if (err)
- extent_io_tree_panic(tree, err);
- set_state_bits(tree, prealloc, &bits);
- clear_state_bit(tree, prealloc, &clear_bits, 0);
- prealloc = NULL;
- goto out;
- }
- goto search_again;
- out:
- spin_unlock(&tree->lock);
- if (prealloc)
- free_extent_state(prealloc);
- return err;
- search_again:
- if (start > end)
- goto out;
- spin_unlock(&tree->lock);
- if (mask & __GFP_WAIT)
- cond_resched();
- goto again;
- }
- int set_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
- gfp_t mask)
- {
- return set_extent_bit(tree, start, end, EXTENT_DIRTY, NULL,
- NULL, mask);
- }
- int set_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
- int bits, gfp_t mask)
- {
- return set_extent_bit(tree, start, end, bits, NULL,
- NULL, mask);
- }
- int clear_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
- int bits, gfp_t mask)
- {
- return clear_extent_bit(tree, start, end, bits, 0, 0, NULL, mask);
- }
- int set_extent_delalloc(struct extent_io_tree *tree, u64 start, u64 end,
- struct extent_state **cached_state, gfp_t mask)
- {
- return set_extent_bit(tree, start, end,
- EXTENT_DELALLOC | EXTENT_UPTODATE,
- NULL, cached_state, mask);
- }
- int clear_extent_dirty(struct extent_io_tree *tree, u64 start, u64 end,
- gfp_t mask)
- {
- return clear_extent_bit(tree, start, end,
- EXTENT_DIRTY | EXTENT_DELALLOC |
- EXTENT_DO_ACCOUNTING, 0, 0, NULL, mask);
- }
- int set_extent_new(struct extent_io_tree *tree, u64 start, u64 end,
- gfp_t mask)
- {
- return set_extent_bit(tree, start, end, EXTENT_NEW, NULL,
- NULL, mask);
- }
- int set_extent_uptodate(struct extent_io_tree *tree, u64 start, u64 end,
- struct extent_state **cached_state, gfp_t mask)
- {
- return set_extent_bit(tree, start, end, EXTENT_UPTODATE, 0,
- cached_state, mask);
- }
- static int clear_extent_uptodate(struct extent_io_tree *tree, u64 start,
- u64 end, struct extent_state **cached_state,
- gfp_t mask)
- {
- return clear_extent_bit(tree, start, end, EXTENT_UPTODATE, 0, 0,
- cached_state, mask);
- }
- int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
- int bits, struct extent_state **cached_state)
- {
- int err;
- u64 failed_start;
- while (1) {
- err = __set_extent_bit(tree, start, end, EXTENT_LOCKED | bits,
- EXTENT_LOCKED, &failed_start,
- cached_state, GFP_NOFS);
- if (err == -EEXIST) {
- wait_extent_bit(tree, failed_start, end, EXTENT_LOCKED);
- start = failed_start;
- } else
- break;
- WARN_ON(start > end);
- }
- return err;
- }
- int lock_extent(struct extent_io_tree *tree, u64 start, u64 end)
- {
- return lock_extent_bits(tree, start, end, 0, NULL);
- }
- int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end)
- {
- int err;
- u64 failed_start;
- err = __set_extent_bit(tree, start, end, EXTENT_LOCKED, EXTENT_LOCKED,
- &failed_start, NULL, GFP_NOFS);
- if (err == -EEXIST) {
- if (failed_start > start)
- clear_extent_bit(tree, start, failed_start - 1,
- EXTENT_LOCKED, 1, 0, NULL, GFP_NOFS);
- return 0;
- }
- return 1;
- }
- int unlock_extent_cached(struct extent_io_tree *tree, u64 start, u64 end,
- struct extent_state **cached, gfp_t mask)
- {
- return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, cached,
- mask);
- }
- int unlock_extent(struct extent_io_tree *tree, u64 start, u64 end)
- {
- return clear_extent_bit(tree, start, end, EXTENT_LOCKED, 1, 0, NULL,
- GFP_NOFS);
- }
- static int set_range_writeback(struct extent_io_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++;
- }
- return 0;
- }
- struct extent_state *find_first_extent_bit_state(struct extent_io_tree *tree,
- u64 start, int bits)
- {
- struct rb_node *node;
- struct extent_state *state;
- node = tree_search(tree, start);
- if (!node)
- goto out;
- while (1) {
- state = rb_entry(node, struct extent_state, rb_node);
- if (state->end >= start && (state->state & bits))
- return state;
- node = rb_next(node);
- if (!node)
- break;
- }
- out:
- return NULL;
- }
- int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
- u64 *start_ret, u64 *end_ret, int bits)
- {
- struct extent_state *state;
- int ret = 1;
- spin_lock(&tree->lock);
- state = find_first_extent_bit_state(tree, start, bits);
- if (state) {
- *start_ret = state->start;
- *end_ret = state->end;
- ret = 0;
- }
- spin_unlock(&tree->lock);
- return ret;
- }
- static noinline u64 find_delalloc_range(struct extent_io_tree *tree,
- u64 *start, u64 *end, u64 max_bytes,
- struct extent_state **cached_state)
- {
- struct rb_node *node;
- struct extent_state *state;
- u64 cur_start = *start;
- u64 found = 0;
- u64 total_bytes = 0;
- spin_lock(&tree->lock);
- node = tree_search(tree, cur_start);
- if (!node) {
- if (!found)
- *end = (u64)-1;
- goto out;
- }
- while (1) {
- state = rb_entry(node, struct extent_state, rb_node);
- if (found && (state->start != cur_start ||
- (state->state & EXTENT_BOUNDARY))) {
- goto out;
- }
- if (!(state->state & EXTENT_DELALLOC)) {
- if (!found)
- *end = state->end;
- goto out;
- }
- if (!found) {
- *start = state->start;
- *cached_state = state;
- atomic_inc(&state->refs);
- }
- found++;
- *end = state->end;
- cur_start = state->end + 1;
- node = rb_next(node);
- if (!node)
- break;
- total_bytes += state->end - state->start + 1;
- if (total_bytes >= max_bytes)
- break;
- }
- out:
- spin_unlock(&tree->lock);
- return found;
- }
- static noinline void __unlock_for_delalloc(struct inode *inode,
- struct page *locked_page,
- u64 start, u64 end)
- {
- int ret;
- struct page *pages[16];
- unsigned long index = start >> PAGE_CACHE_SHIFT;
- unsigned long end_index = end >> PAGE_CACHE_SHIFT;
- unsigned long nr_pages = end_index - index + 1;
- int i;
- if (index == locked_page->index && end_index == index)
- return;
- while (nr_pages > 0) {
- ret = find_get_pages_contig(inode->i_mapping, index,
- min_t(unsigned long, nr_pages,
- ARRAY_SIZE(pages)), pages);
- for (i = 0; i < ret; i++) {
- if (pages[i] != locked_page)
- unlock_page(pages[i]);
- page_cache_release(pages[i]);
- }
- nr_pages -= ret;
- index += ret;
- cond_resched();
- }
- }
- static noinline int lock_delalloc_pages(struct inode *inode,
- struct page *locked_page,
- u64 delalloc_start,
- u64 delalloc_end)
- {
- unsigned long index = delalloc_start >> PAGE_CACHE_SHIFT;
- unsigned long start_index = index;
- unsigned long end_index = delalloc_end >> PAGE_CACHE_SHIFT;
- unsigned long pages_locked = 0;
- struct page *pages[16];
- unsigned long nrpages;
- int ret;
- int i;
-
- if (index == locked_page->index && index == end_index)
- return 0;
-
- nrpages = end_index - index + 1;
- while (nrpages > 0) {
- ret = find_get_pages_contig(inode->i_mapping, index,
- min_t(unsigned long,
- nrpages, ARRAY_SIZE(pages)), pages);
- if (ret == 0) {
- ret = -EAGAIN;
- goto done;
- }
-
- for (i = 0; i < ret; i++) {
- if (pages[i] != locked_page) {
- lock_page(pages[i]);
- if (!PageDirty(pages[i]) ||
- pages[i]->mapping != inode->i_mapping) {
- ret = -EAGAIN;
- unlock_page(pages[i]);
- page_cache_release(pages[i]);
- goto done;
- }
- }
- page_cache_release(pages[i]);
- pages_locked++;
- }
- nrpages -= ret;
- index += ret;
- cond_resched();
- }
- ret = 0;
- done:
- if (ret && pages_locked) {
- __unlock_for_delalloc(inode, locked_page,
- delalloc_start,
- ((u64)(start_index + pages_locked - 1)) <<
- PAGE_CACHE_SHIFT);
- }
- return ret;
- }
- static noinline u64 find_lock_delalloc_range(struct inode *inode,
- struct extent_io_tree *tree,
- struct page *locked_page,
- u64 *start, u64 *end,
- u64 max_bytes)
- {
- u64 delalloc_start;
- u64 delalloc_end;
- u64 found;
- struct extent_state *cached_state = NULL;
- int ret;
- int loops = 0;
- again:
-
- delalloc_start = *start;
- delalloc_end = 0;
- found = find_delalloc_range(tree, &delalloc_start, &delalloc_end,
- max_bytes, &cached_state);
- if (!found || delalloc_end <= *start) {
- *start = delalloc_start;
- *end = delalloc_end;
- free_extent_state(cached_state);
- return found;
- }
- if (delalloc_start < *start)
- delalloc_start = *start;
- if (delalloc_end + 1 - delalloc_start > max_bytes && loops)
- delalloc_end = delalloc_start + PAGE_CACHE_SIZE - 1;
-
- ret = lock_delalloc_pages(inode, locked_page,
- delalloc_start, delalloc_end);
- if (ret == -EAGAIN) {
- free_extent_state(cached_state);
- if (!loops) {
- unsigned long offset = (*start) & (PAGE_CACHE_SIZE - 1);
- max_bytes = PAGE_CACHE_SIZE - offset;
- loops = 1;
- goto again;
- } else {
- found = 0;
- goto out_failed;
- }
- }
- BUG_ON(ret);
-
- lock_extent_bits(tree, delalloc_start, delalloc_end, 0, &cached_state);
-
- ret = test_range_bit(tree, delalloc_start, delalloc_end,
- EXTENT_DELALLOC, 1, cached_state);
- if (!ret) {
- unlock_extent_cached(tree, delalloc_start, delalloc_end,
- &cached_state, GFP_NOFS);
- __unlock_for_delalloc(inode, locked_page,
- delalloc_start, delalloc_end);
- cond_resched();
- goto again;
- }
- free_extent_state(cached_state);
- *start = delalloc_start;
- *end = delalloc_end;
- out_failed:
- return found;
- }
- int extent_clear_unlock_delalloc(struct inode *inode,
- struct extent_io_tree *tree,
- u64 start, u64 end, struct page *locked_page,
- unsigned long op)
- {
- int ret;
- struct page *pages[16];
- unsigned long index = start >> PAGE_CACHE_SHIFT;
- unsigned long end_index = end >> PAGE_CACHE_SHIFT;
- unsigned long nr_pages = end_index - index + 1;
- int i;
- int clear_bits = 0;
- if (op & EXTENT_CLEAR_UNLOCK)
- clear_bits |= EXTENT_LOCKED;
- if (op & EXTENT_CLEAR_DIRTY)
- clear_bits |= EXTENT_DIRTY;
- if (op & EXTENT_CLEAR_DELALLOC)
- clear_bits |= EXTENT_DELALLOC;
- clear_extent_bit(tree, start, end, clear_bits, 1, 0, NULL, GFP_NOFS);
- if (!(op & (EXTENT_CLEAR_UNLOCK_PAGE | EXTENT_CLEAR_DIRTY |
- EXTENT_SET_WRITEBACK | EXTENT_END_WRITEBACK |
- EXTENT_SET_PRIVATE2)))
- return 0;
- while (nr_pages > 0) {
- ret = find_get_pages_contig(inode->i_mapping, index,
- min_t(unsigned long,
- nr_pages, ARRAY_SIZE(pages)), pages);
- for (i = 0; i < ret; i++) {
- if (op & EXTENT_SET_PRIVATE2)
- SetPagePrivate2(pages[i]);
- if (pages[i] == locked_page) {
- page_cache_release(pages[i]);
- continue;
- }
- if (op & EXTENT_CLEAR_DIRTY)
- clear_page_dirty_for_io(pages[i]);
- if (op & EXTENT_SET_WRITEBACK)
- set_page_writeback(pages[i]);
- if (op & EXTENT_END_WRITEBACK)
- end_page_writeback(pages[i]);
- if (op & EXTENT_CLEAR_UNLOCK_PAGE)
- unlock_page(pages[i]);
- page_cache_release(pages[i]);
- }
- nr_pages -= ret;
- index += ret;
- cond_resched();
- }
- return 0;
- }
- u64 count_range_bits(struct extent_io_tree *tree,
- u64 *start, u64 search_end, u64 max_bytes,
- unsigned long bits, int contig)
- {
- struct rb_node *node;
- struct extent_state *state;
- u64 cur_start = *start;
- u64 total_bytes = 0;
- u64 last = 0;
- int found = 0;
- if (search_end <= cur_start) {
- WARN_ON(1);
- return 0;
- }
- spin_lock(&tree->lock);
- if (cur_start == 0 && bits == EXTENT_DIRTY) {
- total_bytes = tree->dirty_bytes;
- goto out;
- }
- node = tree_search(tree, cur_start);
- if (!node)
- goto out;
- while (1) {
- state = rb_entry(node, struct extent_state, rb_node);
- if (state->start > search_end)
- break;
- if (contig && found && state->start > last + 1)
- break;
- if (state->end >= cur_start && (state->state & bits) == bits) {
- total_bytes += min(search_end, state->end) + 1 -
- max(cur_start, state->start);
- if (total_bytes >= max_bytes)
- break;
- if (!found) {
- *start = max(cur_start, state->start);
- found = 1;
- }
- last = state->end;
- } else if (contig && found) {
- break;
- }
- node = rb_next(node);
- if (!node)
- break;
- }
- out:
- spin_unlock(&tree->lock);
- return total_bytes;
- }
- int set_state_private(struct extent_io_tree *tree, u64 start, u64 private)
- {
- struct rb_node *node;
- struct extent_state *state;
- int ret = 0;
- spin_lock(&tree->lock);
- node = tree_search(tree, start);
- if (!node) {
- ret = -ENOENT;
- goto out;
- }
- state = rb_entry(node, struct extent_state, rb_node);
- if (state->start != start) {
- ret = -ENOENT;
- goto out;
- }
- state->private = private;
- out:
- spin_unlock(&tree->lock);
- return ret;
- }
- int get_state_private(struct extent_io_tree *tree, u64 start, u64 *private)
- {
- struct rb_node *node;
- struct extent_state *state;
- int ret = 0;
- spin_lock(&tree->lock);
- node = tree_search(tree, start);
- if (!node) {
- ret = -ENOENT;
- goto out;
- }
- state = rb_entry(node, struct extent_state, rb_node);
- if (state->start != start) {
- ret = -ENOENT;
- goto out;
- }
- *private = state->private;
- out:
- spin_unlock(&tree->lock);
- return ret;
- }
- int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
- int bits, int filled, struct extent_state *cached)
- {
- struct extent_state *state = NULL;
- struct rb_node *node;
- int bitset = 0;
- spin_lock(&tree->lock);
- if (cached && cached->tree && cached->start <= start &&
- cached->end > start)
- node = &cached->rb_node;
- else
- node = tree_search(tree, start);
- while (node && start <= end) {
- state = rb_entry(node, struct extent_state, rb_node);
- if (filled && state->start > start) {
- bitset = 0;
- break;
- }
- if (state->start > end)
- break;
- if (state->state & bits) {
- bitset = 1;
- if (!filled)
- break;
- } else if (filled) {
- bitset = 0;
- break;
- }
- if (state->end == (u64)-1)
- break;
- start = state->end + 1;
- if (start > end)
- break;
- node = rb_next(node);
- if (!node) {
- if (filled)
- bitset = 0;
- break;
- }
- }
- spin_unlock(&tree->lock);
- return bitset;
- }
- static void check_page_uptodate(struct extent_io_tree *tree, struct page *page)
- {
- u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
- u64 end = start + PAGE_CACHE_SIZE - 1;
- if (test_range_bit(tree, start, end, EXTENT_UPTODATE, 1, NULL))
- SetPageUptodate(page);
- }
- static void check_page_locked(struct extent_io_tree *tree, struct page *page)
- {
- u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
- u64 end = start + PAGE_CACHE_SIZE - 1;
- if (!test_range_bit(tree, start, end, EXTENT_LOCKED, 0, NULL))
- unlock_page(page);
- }
- static void check_page_writeback(struct extent_io_tree *tree,
- struct page *page)
- {
- end_page_writeback(page);
- }
- struct io_failure_record {
- struct page *page;
- u64 start;
- u64 len;
- u64 logical;
- unsigned long bio_flags;
- int this_mirror;
- int failed_mirror;
- int in_validation;
- };
- static int free_io_failure(struct inode *inode, struct io_failure_record *rec,
- int did_repair)
- {
- int ret;
- int err = 0;
- struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree;
- set_state_private(failure_tree, rec->start, 0);
- ret = clear_extent_bits(failure_tree, rec->start,
- rec->start + rec->len - 1,
- EXTENT_LOCKED | EXTENT_DIRTY, GFP_NOFS);
- if (ret)
- err = ret;
- if (did_repair) {
- ret = clear_extent_bits(&BTRFS_I(inode)->io_tree, rec->start,
- rec->start + rec->len - 1,
- EXTENT_DAMAGED, GFP_NOFS);
- if (ret && !err)
- err = ret;
- }
- kfree(rec);
- return err;
- }
- static void repair_io_failure_callback(struct bio *bio, int err)
- {
- complete(bio->bi_private);
- }
- int repair_io_failure(struct btrfs_mapping_tree *map_tree, u64 start,
- u64 length, u64 logical, struct page *page,
- int mirror_num)
- {
- struct bio *bio;
- struct btrfs_device *dev;
- DECLARE_COMPLETION_ONSTACK(compl);
- u64 map_length = 0;
- u64 sector;
- struct btrfs_bio *bbio = NULL;
- int ret;
- BUG_ON(!mirror_num);
- bio = bio_alloc(GFP_NOFS, 1);
- if (!bio)
- return -EIO;
- bio->bi_private = &compl;
- bio->bi_end_io = repair_io_failure_callback;
- bio->bi_size = 0;
- map_length = length;
- ret = btrfs_map_block(map_tree, WRITE, logical,
- &map_length, &bbio, mirror_num);
- if (ret) {
- bio_put(bio);
- return -EIO;
- }
- BUG_ON(mirror_num != bbio->mirror_num);
- sector = bbio->stripes[mirror_num-1].physical >> 9;
- bio->bi_sector = sector;
- dev = bbio->stripes[mirror_num-1].dev;
- kfree(bbio);
- if (!dev || !dev->bdev || !dev->writeable) {
- bio_put(bio);
- return -EIO;
- }
- bio->bi_bdev = dev->bdev;
- bio_add_page(bio, page, length, start-page_offset(page));
- btrfsic_submit_bio(WRITE_SYNC, bio);
- wait_for_completion(&compl);
- if (!test_bit(BIO_UPTODATE, &bio->bi_flags)) {
-
- bio_put(bio);
- return -EIO;
- }
- printk(KERN_INFO "btrfs read error corrected: ino %lu off %llu (dev %s "
- "sector %llu)\n", page->mapping->host->i_ino, start,
- dev->name, sector);
- bio_put(bio);
- return 0;
- }
- int repair_eb_io_failure(struct btrfs_root *root, struct extent_buffer *eb,
- int mirror_num)
- {
- struct btrfs_mapping_tree *map_tree = &root->fs_info->mapping_tree;
- u64 start = eb->start;
- unsigned long i, num_pages = num_extent_pages(eb->start, eb->len);
- int ret = 0;
- for (i = 0; i < num_pages; i++) {
- struct page *p = extent_buffer_page(eb, i);
- ret = repair_io_failure(map_tree, start, PAGE_CACHE_SIZE,
- start, p, mirror_num);
- if (ret)
- break;
- start += PAGE_CACHE_SIZE;
- }
- return ret;
- }
- static int clean_io_failure(u64 start, struct page *page)
- {
- u64 private;
- u64 private_failure;
- struct io_failure_record *failrec;
- struct btrfs_mapping_tree *map_tree;
- struct extent_state *state;
- int num_copies;
- int did_repair = 0;
- int ret;
- struct inode *inode = page->mapping->host;
- private = 0;
- ret = count_range_bits(&BTRFS_I(inode)->io_failure_tree, &private,
- (u64)-1, 1, EXTENT_DIRTY, 0);
- if (!ret)
- return 0;
- ret = get_state_private(&BTRFS_I(inode)->io_failure_tree, start,
- &private_failure);
- if (ret)
- return 0;
- failrec = (struct io_failure_record *)(unsigned long) private_failure;
- BUG_ON(!failrec->this_mirror);
- if (failrec->in_validation) {
-
- pr_debug("clean_io_failure: freeing dummy error at %llu\n",
- failrec->start);
- did_repair = 1;
- goto out;
- }
- spin_lock(&BTRFS_I(inode)->io_tree.lock);
- state = find_first_extent_bit_state(&BTRFS_I(inode)->io_tree,
- failrec->start,
- EXTENT_LOCKED);
- spin_unlock(&BTRFS_I(inode)->io_tree.lock);
- if (state && state->start == failrec->start) {
- map_tree = &BTRFS_I(inode)->root->fs_info->mapping_tree;
- num_copies = btrfs_num_copies(map_tree, failrec->logical,
- failrec->len);
- if (num_copies > 1) {
- ret = repair_io_failure(map_tree, start, failrec->len,
- failrec->logical, page,
- failrec->failed_mirror);
- did_repair = !ret;
- }
- }
- out:
- if (!ret)
- ret = free_io_failure(inode, failrec, did_repair);
- return ret;
- }
- static int bio_readpage_error(struct bio *failed_bio, struct page *page,
- u64 start, u64 end, int failed_mirror,
- struct extent_state *state)
- {
- struct io_failure_record *failrec = NULL;
- u64 private;
- struct extent_map *em;
- struct inode *inode = page->mapping->host;
- struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree;
- struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
- struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
- struct bio *bio;
- int num_copies;
- int ret;
- int read_mode;
- u64 logical;
- BUG_ON(failed_bio->bi_rw & REQ_WRITE);
- ret = get_state_private(failure_tree, start, &private);
- if (ret) {
- failrec = kzalloc(sizeof(*failrec), GFP_NOFS);
- if (!failrec)
- return -ENOMEM;
- failrec->start = start;
- failrec->len = end - start + 1;
- failrec->this_mirror = 0;
- failrec->bio_flags = 0;
- failrec->in_validation = 0;
- read_lock(&em_tree->lock);
- em = lookup_extent_mapping(em_tree, start, failrec->len);
- if (!em) {
- read_unlock(&em_tree->lock);
- kfree(failrec);
- return -EIO;
- }
- if (em->start > start || em->start + em->len < start) {
- free_extent_map(em);
- em = NULL;
- }
- read_unlock(&em_tree->lock);
- if (!em || IS_ERR(em)) {
- kfree(failrec);
- return -EIO;
- }
- logical = start - em->start;
- logical = em->block_start + logical;
- if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
- logical = em->block_start;
- failrec->bio_flags = EXTENT_BIO_COMPRESSED;
- extent_set_compress_type(&failrec->bio_flags,
- em->compress_type);
- }
- pr_debug("bio_readpage_error: (new) logical=%llu, start=%llu, "
- "len=%llu\n", logical, start, failrec->len);
- failrec->logical = logical;
- free_extent_map(em);
-
- ret = set_extent_bits(failure_tree, start, end,
- EXTENT_LOCKED | EXTENT_DIRTY, GFP_NOFS);
- if (ret >= 0)
- ret = set_state_private(failure_tree, start,
- (u64)(unsigned long)failrec);
-
- if (ret >= 0)
- ret = set_extent_bits(tree, start, end, EXTENT_DAMAGED,
- GFP_NOFS);
- if (ret < 0) {
- kfree(failrec);
- return ret;
- }
- } else {
- failrec = (struct io_failure_record *)(unsigned long)private;
- pr_debug("bio_readpage_error: (found) logical=%llu, "
- "start=%llu, len=%llu, validation=%d\n",
- failrec->logical, failrec->start, failrec->len,
- failrec->in_validation);
- }
- num_copies = btrfs_num_copies(
- &BTRFS_I(inode)->root->fs_info->mapping_tree,
- failrec->logical, failrec->len);
- if (num_copies == 1) {
- pr_debug("bio_readpage_error: cannot repair, num_copies == 1. "
- "state=%p, num_copies=%d, next_mirror %d, "
- "failed_mirror %d\n", state, num_copies,
- failrec->this_mirror, failed_mirror);
- free_io_failure(inode, failrec, 0);
- return -EIO;
- }
- if (!state) {
- spin_lock(&tree->lock);
- state = find_first_extent_bit_state(tree, failrec->start,
- EXTENT_LOCKED);
- if (state && state->start != failrec->start)
- state = NULL;
- spin_unlock(&tree->lock);
- }
- if (failed_bio->bi_vcnt > 1) {
- BUG_ON(failrec->in_validation);
- failrec->in_validation = 1;
- failrec->this_mirror = failed_mirror;
- read_mode = READ_SYNC | REQ_FAILFAST_DEV;
- } else {
- if (failrec->in_validation) {
- BUG_ON(failrec->this_mirror != failed_mirror);
- failrec->in_validation = 0;
- failrec->this_mirror = 0;
- }
- failrec->failed_mirror = failed_mirror;
- failrec->this_mirror++;
- if (failrec->this_mirror == failed_mirror)
- failrec->this_mirror++;
- read_mode = READ_SYNC;
- }
- if (!state || failrec->this_mirror > num_copies) {
- pr_debug("bio_readpage_error: (fail) state=%p, num_copies=%d, "
- "next_mirror %d, failed_mirror %d\n", state,
- num_copies, failrec->this_mirror, failed_mirror);
- free_io_failure(inode, failrec, 0);
- return -EIO;
- }
- bio = bio_alloc(GFP_NOFS, 1);
- if (!bio) {
- free_io_failure(inode, failrec, 0);
- return -EIO;
- }
- bio->bi_private = state;
- bio->bi_end_io = failed_bio->bi_end_io;
- bio->bi_sector = failrec->logical >> 9;
- bio->bi_bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
- bio->bi_size = 0;
- bio_add_page(bio, page, failrec->len, start - page_offset(page));
- pr_debug("bio_readpage_error: submitting new read[%#x] to "
- "this_mirror=%d, num_copies=%d, in_validation=%d\n", read_mode,
- failrec->this_mirror, num_copies, failrec->in_validation);
- ret = tree->ops->submit_bio_hook(inode, read_mode, bio,
- failrec->this_mirror,
- failrec->bio_flags, 0);
- return ret;
- }
- int end_extent_writepage(struct page *page, int err, u64 start, u64 end)
- {
- int uptodate = (err == 0);
- struct extent_io_tree *tree;
- int ret;
- tree = &BTRFS_I(page->mapping->host)->io_tree;
- if (tree->ops && tree->ops->writepage_end_io_hook) {
- ret = tree->ops->writepage_end_io_hook(page, start,
- end, NULL, uptodate);
- if (ret)
- uptodate = 0;
- }
- if (!uptodate && tree->ops &&
- tree->ops->writepage_io_failed_hook) {
- ret = tree->ops->writepage_io_failed_hook(NULL, page,
- start, end, NULL);
-
- if (ret == 0)
- return 1;
- }
- if (!uptodate) {
- clear_extent_uptodate(tree, start, end, NULL, GFP_NOFS);
- ClearPageUptodate(page);
- SetPageError(page);
- }
- return 0;
- }
- static void end_bio_extent_writepage(struct bio *bio, int err)
- {
- struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
- struct extent_io_tree *tree;
- u64 start;
- u64 end;
- int whole_page;
- do {
- struct page *page = bvec->bv_page;
- tree = &BTRFS_I(page->mapping->host)->io_tree;
- start = ((u64)page->index << PAGE_CACHE_SHIFT) +
- bvec->bv_offset;
- end = start + bvec->bv_len - 1;
- if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE)
- whole_page = 1;
- else
- whole_page = 0;
- if (--bvec >= bio->bi_io_vec)
- prefetchw(&bvec->bv_page->flags);
- if (end_extent_writepage(page, err, start, end))
- continue;
- if (whole_page)
- end_page_writeback(page);
- else
- check_page_writeback(tree, page);
- } while (bvec >= bio->bi_io_vec);
- bio_put(bio);
- }
- static void end_bio_extent_readpage(struct bio *bio, int err)
- {
- int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
- struct bio_vec *bvec_end = bio->bi_io_vec + bio->bi_vcnt - 1;
- struct bio_vec *bvec = bio->bi_io_vec;
- struct extent_io_tree *tree;
- u64 start;
- u64 end;
- int whole_page;
- int mirror;
- int ret;
- if (err)
- uptodate = 0;
- do {
- struct page *page = bvec->bv_page;
- struct extent_state *cached = NULL;
- struct extent_state *state;
- pr_debug("end_bio_extent_readpage: bi_vcnt=%d, idx=%d, err=%d, "
- "mirror=%ld\n", bio->bi_vcnt, bio->bi_idx, err,
- (long int)bio->bi_bdev);
- tree = &BTRFS_I(page->mapping->host)->io_tree;
- start = ((u64)page->index << PAGE_CACHE_SHIFT) +
- bvec->bv_offset;
- end = start + bvec->bv_len - 1;
- if (bvec->bv_offset == 0 && bvec->bv_len == PAGE_CACHE_SIZE)
- whole_page = 1;
- else
- whole_page = 0;
- if (++bvec <= bvec_end)
- prefetchw(&bvec->bv_page->flags);
- spin_lock(&tree->lock);
- state = find_first_extent_bit_state(tree, start, EXTENT_LOCKED);
- if (state && state->start == start) {
- cache_state(state, &cached);
- }
- spin_unlock(&tree->lock);
- mirror = (int)(unsigned long)bio->bi_bdev;
- if (uptodate && tree->ops && tree->ops->readpage_end_io_hook) {
- ret = tree->ops->readpage_end_io_hook(page, start, end,
- state, mirror);
- if (ret)
- uptodate = 0;
- else
- clean_io_failure(start, page);
- }
- if (!uptodate && tree->ops && tree->ops->readpage_io_failed_hook) {
- ret = tree->ops->readpage_io_failed_hook(page, mirror);
- if (!ret && !err &&
- test_bit(BIO_UPTODATE, &bio->bi_flags))
- uptodate = 1;
- } else if (!uptodate) {
- ret = bio_readpage_error(bio, page, start, end, mirror, NULL);
- if (ret == 0) {
- uptodate =
- test_bit(BIO_UPTODATE, &bio->bi_flags);
- if (err)
- uptodate = 0;
- uncache_state(&cached);
- continue;
- }
- }
- if (uptodate && tree->track_uptodate) {
- set_extent_uptodate(tree, start, end, &cached,
- GFP_ATOMIC);
- }
- unlock_extent_cached(tree, start, end, &cached, GFP_ATOMIC);
- if (whole_page) {
- if (uptodate) {
- SetPageUptodate(page);
- } else {
- ClearPageUptodate(page);
- SetPageError(page);
- }
- unlock_page(page);
- } else {
- if (uptodate) {
- check_page_uptodate(tree, page);
- } else {
- ClearPageUptodate(page);
- SetPageError(page);
- }
- check_page_locked(tree, page);
- }
- } while (bvec <= bvec_end);
- bio_put(bio);
- }
- struct bio *
- btrfs_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs,
- gfp_t gfp_flags)
- {
- struct bio *bio;
- bio = bio_alloc(gfp_flags, nr_vecs);
- if (bio == NULL && (current->flags & PF_MEMALLOC)) {
- while (!bio && (nr_vecs /= 2))
- bio = bio_alloc(gfp_flags, nr_vecs);
- }
- if (bio) {
- bio->bi_size = 0;
- bio->bi_bdev = bdev;
- bio->bi_sector = first_sector;
- }
- return bio;
- }
- static int __must_check submit_one_bio(int rw, struct bio *bio,
- int mirror_num, unsigned long bio_flags)
- {
- int ret = 0;
- struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
- struct page *page = bvec->bv_page;
- struct extent_io_tree *tree = bio->bi_private;
- u64 start;
- start = ((u64)page->index << PAGE_CACHE_SHIFT) + bvec->bv_offset;
- bio->bi_private = NULL;
- bio_get(bio);
- if (tree->ops && tree->ops->submit_bio_hook)
- ret = tree->ops->submit_bio_hook(page->mapping->host, rw, bio,
- mirror_num, bio_flags, start);
- else
- btrfsic_submit_bio(rw, bio);
- if (bio_flagged(bio, BIO_EOPNOTSUPP))
- ret = -EOPNOTSUPP;
- bio_put(bio);
- return ret;
- }
- static int merge_bio(struct extent_io_tree *tree, struct page *page,
- unsigned long offset, size_t size, struct bio *bio,
- unsigned long bio_flags)
- {
- int ret = 0;
- if (tree->ops && tree->ops->merge_bio_hook)
- ret = tree->ops->merge_bio_hook(page, offset, size, bio,
- bio_flags);
- BUG_ON(ret < 0);
- return ret;
- }
- static int submit_extent_page(int rw, struct extent_io_tree *tree,
- struct page *page, sector_t sector,
- size_t size, unsigned long offset,
- struct block_device *bdev,
- struct bio **bio_ret,
- unsigned long max_pages,
- bio_end_io_t end_io_func,
- int mirror_num,
- unsigned long prev_bio_flags,
- unsigned long bio_flags)
- {
- int ret = 0;
- struct bio *bio;
- int nr;
- int contig = 0;
- int this_compressed = bio_flags & EXTENT_BIO_COMPRESSED;
- int old_compressed = prev_bio_flags & EXTENT_BIO_COMPRESSED;
- size_t page_size = min_t(size_t, size, PAGE_CACHE_SIZE);
- if (bio_ret && *bio_ret) {
- bio = *bio_ret;
- if (old_compressed)
- contig = bio->bi_sector == sector;
- else
- contig = bio->bi_sector + (bio->bi_size >> 9) ==
- sector;
- if (prev_bio_flags != bio_flags || !contig ||
- merge_bio(tree, page, offset, page_size, bio, bio_flags) ||
- bio_add_page(bio, page, page_size, offset) < page_size) {
- ret = submit_one_bio(rw, bio, mirror_num,
- prev_bio_flags);
- if (ret < 0)
- return ret;
- bio = NULL;
- } else {
- return 0;
- }
- }
- if (this_compressed)
- nr = BIO_MAX_PAGES;
- else
- nr = bio_get_nr_vecs(bdev);
- bio = btrfs_bio_alloc(bdev, sector, nr, GFP_NOFS | __GFP_HIGH);
- if (!bio)
- return -ENOMEM;
- bio_add_page(bio, page, page_size, offset);
- bio->bi_end_io = end_io_func;
- bio->bi_private = tree;
- if (bio_ret)
- *bio_ret = bio;
- else
- ret = submit_one_bio(rw, bio, mirror_num, bio_flags);
- return ret;
- }
- void attach_extent_buffer_page(struct extent_buffer *eb, struct page *page)
- {
- if (!PagePrivate(page)) {
- SetPagePrivate(page);
- page_cache_get(page);
- set_page_private(page, (unsigned long)eb);
- } else {
- WARN_ON(page->private != (unsigned long)eb);
- }
- }
- void set_page_extent_mapped(struct page *page)
- {
- if (!PagePrivate(page)) {
- SetPagePrivate(page);
- page_cache_get(page);
- set_page_private(page, EXTENT_PAGE_PRIVATE);
- }
- }
- static int __extent_read_full_page(struct extent_io_tree *tree,
- struct page *page,
- get_extent_t *get_extent,
- struct bio **bio, int mirror_num,
- unsigned long *bio_flags)
- {
- struct inode *inode = page->mapping->host;
- u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
- u64 page_end = start + PAGE_CACHE_SIZE - 1;
- u64 end;
- u64 cur = start;
- u64 extent_offset;
- u64 last_byte = i_size_read(inode);
- u64 block_start;
- u64 cur_end;
- sector_t sector;
- struct extent_map *em;
- struct block_device *bdev;
- struct btrfs_ordered_extent *ordered;
- int ret;
- int nr = 0;
- size_t pg_offset = 0;
- size_t iosize;
- size_t disk_io_size;
- size_t blocksize = inode->i_sb->s_blocksize;
- unsigned long this_bio_flag = 0;
- set_page_extent_mapped(page);
- if (!PageUptodate(page)) {
- if (cleancache_get_page(page) == 0) {
- BUG_ON(blocksize != PAGE_SIZE);
- goto out;
- }
- }
- end = page_end;
- while (1) {
- lock_extent(tree, start, end);
- ordered = btrfs_lookup_ordered_extent(inode, start);
- if (!ordered)
- break;
- unlock_extent(tree, start, end);
- btrfs_start_ordered_extent(inode, ordered, 1);
- btrfs_put_ordered_extent(ordered);
- }
- if (page->index == last_byte >> PAGE_CACHE_SHIFT) {
- char *userpage;
- size_t zero_offset = last_byte & (PAGE_CACHE_SIZE - 1);
- if (zero_offset) {
- iosize = PAGE_CACHE_SIZE - zero_offset;
- userpage = kmap_atomic(page);
- memset(userpage + zero_offset, 0, iosize);
- flush_dcache_page(page);
- kunmap_atomic(userpage);
- }
- }
- while (cur <= end) {
- if (cur >= last_byte) {
- char *userpage;
- struct extent_state *cached = NULL;
- iosize = PAGE_CACHE_SIZE - pg_offset;
- userpage = kmap_atomic(page);
- memset(userpage + pg_offset, 0, iosize);
- flush_dcache_page(page);
- kunmap_atomic(userpage);
- set_extent_uptodate(tree, cur, cur + iosize - 1,
- &cached, GFP_NOFS);
- unlock_extent_cached(tree, cur, cur + iosize - 1,
- &cached, GFP_NOFS);
- break;
- }
- em = get_extent(inode, page, pg_offset, cur,
- end - cur + 1, 0);
- if (IS_ERR_OR_NULL(em)) {
- SetPageError(page);
- unlock_extent(tree, cur, end);
- break;
- }
- extent_offset = cur - em->start;
- BUG_ON(extent_map_end(em) <= cur);
- BUG_ON(end < cur);
- if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
- this_bio_flag = EXTENT_BIO_COMPRESSED;
- extent_set_compress_type(&this_bio_flag,
- em->compress_type);
- }
- iosize = min(extent_map_end(em) - cur, end - cur + 1);
- cur_end = min(extent_map_end(em) - 1, end);
- iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1);
- if (this_bio_flag & EXTENT_BIO_COMPRESSED) {
- disk_io_size = em->block_len;
- sector = em->block_start >> 9;
- } else {
- sector = (em->block_start + extent_offset) >> 9;
- disk_io_size = iosize;
- }
- bdev = em->bdev;
- block_start = em->block_start;
- if (test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
- block_start = EXTENT_MAP_HOLE;
- free_extent_map(em);
- em = NULL;
-
- if (block_start == EXTENT_MAP_HOLE) {
- char *userpage;
- struct extent_state *cached = NULL;
- userpage = kmap_atomic(page);
- memset(userpage + pg_offset, 0, iosize);
- flush_dcache_page(page);
- kunmap_atomic(userpage);
- set_extent_uptodate(tree, cur, cur + iosize - 1,
- &cached, GFP_NOFS);
- unlock_extent_cached(tree, cur, cur + iosize - 1,
- &cached, GFP_NOFS);
- cur = cur + iosize;
- pg_offset += iosize;
- continue;
- }
-
- if (test_range_bit(tree, cur, cur_end,
- EXTENT_UPTODATE, 1, NULL)) {
- check_page_uptodate(tree, page);
- unlock_extent(tree, cur, cur + iosize - 1);
- cur = cur + iosize;
- pg_offset += iosize;
- continue;
- }
- if (block_start == EXTENT_MAP_INLINE) {
- SetPageError(page);
- unlock_extent(tree, cur, cur + iosize - 1);
- cur = cur + iosize;
- pg_offset += iosize;
- continue;
- }
- ret = 0;
- if (tree->ops && tree->ops->readpage_io_hook) {
- ret = tree->ops->readpage_io_hook(page, cur,
- cur + iosize - 1);
- }
- if (!ret) {
- unsigned long pnr = (last_byte >> PAGE_CACHE_SHIFT) + 1;
- pnr -= page->index;
- ret = submit_extent_page(READ, tree, page,
- sector, disk_io_size, pg_offset,
- bdev, bio, pnr,
- end_bio_extent_readpage, mirror_num,
- *bio_flags,
- this_bio_flag);
- BUG_ON(ret == -ENOMEM);
- nr++;
- *bio_flags = this_bio_flag;
- }
- if (ret)
- SetPageError(page);
- cur = cur + iosize;
- pg_offset += iosize;
- }
- out:
- if (!nr) {
- if (!PageError(page))
- SetPageUptodate(page);
- unlock_page(page);
- }
- return 0;
- }
- int extent_read_full_page(struct extent_io_tree *tree, struct page *page,
- get_extent_t *get_extent, int mirror_num)
- {
- struct bio *bio = NULL;
- unsigned long bio_flags = 0;
- int ret;
- ret = __extent_read_full_page(tree, page, get_extent, &bio, mirror_num,
- &bio_flags);
- if (bio)
- ret = submit_one_bio(READ, bio, mirror_num, bio_flags);
- return ret;
- }
- static noinline void update_nr_written(struct page *page,
- struct writeback_control *wbc,
- unsigned long nr_written)
- {
- wbc->nr_to_write -= nr_written;
- if (wbc->range_cyclic || (wbc->nr_to_write > 0 &&
- wbc->range_start == 0 && wbc->range_end == LLONG_MAX))
- page->mapping->writeback_index = page->index + nr_written;
- }
- static int __extent_writepage(struct page *page, struct writeback_control *wbc,
- void *data)
- {
- struct inode *inode = page->mapping->host;
- struct extent_page_data *epd = data;
- struct extent_io_tree *tree = epd->tree;
- u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
- u64 delalloc_start;
- u64 page_end = start + PAGE_CACHE_SIZE - 1;
- u64 end;
- u64 cur = start;
- u64 extent_offset;
- u64 last_byte = i_size_read(inode);
- u64 block_start;
- u64 iosize;
- sector_t sector;
- struct extent_state *cached_state = NULL;
- struct extent_map *em;
- struct block_device *bdev;
- int ret;
- int nr = 0;
- size_t pg_offset = 0;
- size_t blocksize;
- loff_t i_size = i_size_read(inode);
- unsigned long end_index = i_size >> PAGE_CACHE_SHIFT;
- u64 nr_delalloc;
- u64 delalloc_end;
- int page_started;
- int compressed;
- int write_flags;
- unsigned long nr_written = 0;
- bool fill_delalloc = true;
- if (wbc->sync_mode == WB_SYNC_ALL)
- write_flags = WRITE_SYNC;
- else
- write_flags = WRITE;
- trace___extent_writepage(page, inode, wbc);
- WARN_ON(!PageLocked(page));
- ClearPageError(page);
- pg_offset = i_size & (PAGE_CACHE_SIZE - 1);
- if (page->index > end_index ||
- (page->index == end_index && !pg_offset)) {
- page->mapping->a_ops->invalidatepage(page, 0);
- unlock_page(page);
- return 0;
- }
- if (page->index == end_index) {
- char *userpage;
- userpage = kmap_atomic(page);
- memset(userpage + pg_offset, 0,
- PAGE_CACHE_SIZE - pg_offset);
- kunmap_atomic(userpage);
- flush_dcache_page(page);
- }
- pg_offset = 0;
- set_page_extent_mapped(page);
- if (!tree->ops || !tree->ops->fill_delalloc)
- fill_delalloc = false;
- delalloc_start = start;
- delalloc_end = 0;
- page_started = 0;
- if (!epd->extent_locked && fill_delalloc) {
- u64 delalloc_to_write = 0;
- update_nr_written(page, wbc, 0);
- while (delalloc_end < page_end) {
- nr_delalloc = find_lock_delalloc_range(inode, tree,
- page,
- &delalloc_start,
- &delalloc_end,
- 128 * 1024 * 1024);
- if (nr_delalloc == 0) {
- delalloc_start = delalloc_end + 1;
- continue;
- }
- ret = tree->ops->fill_delalloc(inode, page,
- delalloc_start,
- delalloc_end,
- &page_started,
- &nr_written);
-
- if (ret) {
- SetPageError(page);
- goto done;
- }
- delalloc_to_write += (delalloc_end - delalloc_start +
- PAGE_CACHE_SIZE) >>
- PAGE_CACHE_SHIFT;
- delalloc_start = delalloc_end + 1;
- }
- if (wbc->nr_to_write < delalloc_to_write) {
- int thresh = 8192;
- if (delalloc_to_write < thresh * 2)
- thresh = delalloc_to_write;
- wbc->nr_to_write = min_t(u64, delalloc_to_write,
- thresh);
- }
- if (page_started) {
- ret = 0;
- wbc->nr_to_write -= nr_written;
- goto done_unlocked;
- }
- }
- if (tree->ops && tree->ops->writepage_start_hook) {
- ret = tree->ops->writepage_start_hook(page, start,
- page_end);
- if (ret) {
-
- if (ret == -EBUSY)
- wbc->pages_skipped++;
- else
- redirty_page_for_writepage(wbc, page);
- update_nr_written(page, wbc, nr_written);
- unlock_page(page);
- ret = 0;
- goto done_unlocked;
- }
- }
- update_nr_written(page, wbc, nr_written + 1);
- end = page_end;
- if (last_byte <= start) {
- if (tree->ops && tree->ops->writepage_end_io_hook)
- tree->ops->writepage_end_io_hook(page, start,
- page_end, NULL, 1);
- goto done;
- }
- blocksize = inode->i_sb->s_blocksize;
- while (cur <= end) {
- if (cur >= last_byte) {
- if (tree->ops && tree->ops->writepage_end_io_hook)
- tree->ops->writepage_end_io_hook(page, cur,
- page_end, NULL, 1);
- break;
- }
- em = epd->get_extent(inode, page, pg_offset, cur,
- end - cur + 1, 1);
- if (IS_ERR_OR_NULL(em)) {
- SetPageError(page);
- break;
- }
- extent_offset = cur - em->start;
- BUG_ON(extent_map_end(em) <= cur);
- BUG_ON(end < cur);
- iosize = min(extent_map_end(em) - cur, end - cur + 1);
- iosize = (iosize + blocksize - 1) & ~((u64)blocksize - 1);
- sector = (em->block_start + extent_offset) >> 9;
- bdev = em->bdev;
- block_start = em->block_start;
- compressed = test_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
- free_extent_map(em);
- em = NULL;
- /*
- * compressed and inline extents are written through other
- * paths in the FS
- */
- if (compressed || block_start == EXTENT_MAP_HOLE ||
- block_start == EXTENT_MAP_INLINE) {
- if (!compressed && tree->ops &&
- tree->ops->writepage_end_io_hook)
- tree->ops->writepage_end_io_hook(page, cur,
- cur + iosize - 1,
- NULL, 1);
- else if (compressed) {
- nr++;
- }
- cur += iosize;
- pg_offset += iosize;
- continue;
- }
-
- if (0 && !test_range_bit(tree, cur, cur + iosize - 1,
- EXTENT_DIRTY, 0, NULL)) {
- cur = cur + iosize;
- pg_offset += iosize;
- continue;
- }
- if (tree->ops && tree->ops->writepage_io_hook) {
- ret = tree->ops->writepage_io_hook(page, cur,
- cur + iosize - 1);
- } else {
- ret = 0;
- }
- if (ret) {
- SetPageError(page);
- } else {
- unsigned long max_nr = end_index + 1;
- set_range_writeback(tree, cur, cur + iosize - 1);
- if (!PageWriteback(page)) {
- printk(KERN_ERR "btrfs warning page %lu not "
- "writeback, cur %llu end %llu\n",
- page->index, (unsigned long long)cur,
- (unsigned long long)end);
- }
- ret = submit_extent_page(write_flags, tree, page,
- sector, iosize, pg_offset,
- bdev, &epd->bio, max_nr,
- end_bio_extent_writepage,
- 0, 0, 0);
- if (ret)
- SetPageError(page);
- }
- cur = cur + iosize;
- pg_offset += iosize;
- nr++;
- }
- done:
- if (nr == 0) {
-
- set_page_writeback(page);
- end_page_writeback(page);
- }
- unlock_page(page);
- done_unlocked:
-
- free_extent_state(cached_state);
- return 0;
- }
- static int eb_wait(void *word)
- {
- io_schedule();
- return 0;
- }
- static void wait_on_extent_buffer_writeback(struct extent_buffer *eb)
- {
- wait_on_bit(&eb->bflags, EXTENT_BUFFER_WRITEBACK, eb_wait,
- TASK_UNINTERRUPTIBLE);
- }
- static int lock_extent_buffer_for_io(struct extent_buffer *eb,
- struct btrfs_fs_info *fs_info,
- struct extent_page_data *epd)
- {
- unsigned long i, num_pages;
- int flush = 0;
- int ret = 0;
- if (!btrfs_try_tree_write_lock(eb)) {
- flush = 1;
- flush_write_bio(epd);
- btrfs_tree_lock(eb);
- }
- if (test_bit(EXTENT_BUFFER_WRITEBACK, &eb->bflags)) {
- btrfs_tree_unlock(eb);
- if (!epd->sync_io)
- return 0;
- if (!flush) {
- flush_write_bio(epd);
- flush = 1;
- }
- while (1) {
- wait_on_extent_buffer_writeback(eb);
- btrfs_tree_lock(eb);
- if (!test_bit(EXTENT_BUFFER_WRITEBACK, &eb->bflags))
- break;
- btrfs_tree_unlock(eb);
- }
- }
- if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)) {
- set_bit(EXTENT_BUFFER_WRITEBACK, &eb->bflags);
- btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN);
- spin_lock(&fs_info->delalloc_lock);
- if (fs_info->dirty_metadata_bytes >= eb->len)
- fs_info->dirty_metadata_bytes -= eb->len;
- else
- WARN_ON(1);
- spin_unlock(&fs_info->delalloc_lock);
- ret = 1;
- }
- btrfs_tree_unlock(eb);
- if (!ret)
- return ret;
- num_pages = num_extent_pages(eb->start, eb->len);
- for (i = 0; i < num_pages; i++) {
- struct page *p = extent_buffer_page(eb, i);
- if (!trylock_page(p)) {
- if (!flush) {
- flush_write_bio(epd);
- flush = 1;
- }
- lock_page(p);
- }
- }
- return ret;
- }
- static void end_extent_buffer_writeback(struct extent_buffer *eb)
- {
- clear_bit(EXTENT_BUFFER_WRITEBACK, &eb->bflags);
- smp_mb__after_clear_bit();
- wake_up_bit(&eb->bflags, EXTENT_BUFFER_WRITEBACK);
- }
- static void end_bio_extent_buffer_writepage(struct bio *bio, int err)
- {
- int uptodate = err == 0;
- struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
- struct extent_buffer *eb;
- int done;
- do {
- struct page *page = bvec->bv_page;
- bvec--;
- eb = (struct extent_buffer *)page->private;
- BUG_ON(!eb);
- done = atomic_dec_and_test(&eb->io_pages);
- if (!uptodate || test_bit(EXTENT_BUFFER_IOERR, &eb->bflags)) {
- set_bit(EXTENT_BUFFER_IOERR, &eb->bflags);
- ClearPageUptodate(page);
- SetPageError(page);
- }
- end_page_writeback(page);
- if (!done)
- continue;
- end_extent_buffer_writeback(eb);
- } while (bvec >= bio->bi_io_vec);
- bio_put(bio);
- }
- static int write_one_eb(struct extent_buffer *eb,
- struct btrfs_fs_info *fs_info,
- struct writeback_control *wbc,
- struct extent_page_data *epd)
- {
- struct block_device *bdev = fs_info->fs_devices->latest_bdev;
- u64 offset = eb->start;
- unsigned long i, num_pages;
- int rw = (epd->sync_io ? WRITE_SYNC : WRITE);
- int ret;
- clear_bit(EXTENT_BUFFER_IOERR, &eb->bflags);
- num_pages = num_extent_pages(eb->start, eb->len);
- atomic_set(&eb->io_pages, num_pages);
- for (i = 0; i < num_pages; i++) {
- struct page *p = extent_buffer_page(eb, i);
- clear_page_dirty_for_io(p);
- set_page_writeback(p);
- ret = submit_extent_page(rw, eb->tree, p, offset >> 9,
- PAGE_CACHE_SIZE, 0, bdev, &epd->bio,
- -1, end_bio_extent_buffer_writepage,
- 0, 0, 0);
- if (ret) {
- set_bit(EXTENT_BUFFER_IOERR, &eb->bflags);
- SetPageError(p);
- if (atomic_sub_and_test(num_pages - i, &eb->io_pages))
- end_extent_buffer_writeback(eb);
- ret = -EIO;
- break;
- }
- offset += PAGE_CACHE_SIZE;
- update_nr_written(p, wbc, 1);
- unlock_page(p);
- }
- if (unlikely(ret)) {
- for (; i < num_pages; i++) {
- struct page *p = extent_buffer_page(eb, i);
- unlock_page(p);
- }
- }
- return ret;
- }
- int btree_write_cache_pages(struct address_space *mapping,
- struct writeback_control *wbc)
- {
- struct extent_io_tree *tree = &BTRFS_I(mapping->host)->io_tree;
- struct btrfs_fs_info *fs_info = BTRFS_I(mapping->host)->root->fs_info;
- struct extent_buffer *eb, *prev_eb = NULL;
- struct extent_page_data epd = {
- .bio = NULL,
- .tree = tree,
- .extent_locked = 0,
- .sync_io = wbc->sync_mode == WB_SYNC_ALL,
- };
- int ret = 0;
- int done = 0;
- int nr_to_write_done = 0;
- struct pagevec pvec;
- int nr_pages;
- pgoff_t index;
- pgoff_t end;
- int scanned = 0;
- int tag;
- pagevec_init(&pvec, 0);
- if (wbc->range_cyclic) {
- index = mapping->writeback_index;
- end = -1;
- } else {
- index = wbc->range_start >> PAGE_CACHE_SHIFT;
- end = wbc->range_end >> PAGE_CACHE_SHIFT;
- scanned = 1;
- }
- if (wbc->sync_mode == WB_SYNC_ALL)
- tag = PAGECACHE_TAG_TOWRITE;
- else
- tag = PAGECACHE_TAG_DIRTY;
- retry:
- if (wbc->sync_mode == WB_SYNC_ALL)
- tag_pages_for_writeback(mapping, index, end);
- while (!done && !nr_to_write_done && (index <= end) &&
- (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, tag,
- min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1))) {
- unsigned i;
- scanned = 1;
- for (i = 0; i < nr_pages; i++) {
- struct page *page = pvec.pages[i];
- if (!PagePrivate(page))
- continue;
- if (!wbc->range_cyclic && page->index > end) {
- done = 1;
- break;
- }
- eb = (struct extent_buffer *)page->private;
- if (!eb) {
- WARN_ON(1);
- continue;
- }
- if (eb == prev_eb)
- continue;
- if (!atomic_inc_not_zero(&eb->refs)) {
- WARN_ON(1);
- continue;
- }
- prev_eb = eb;
- ret = lock_extent_buffer_for_io(eb, fs_info, &epd);
- if (!ret) {
- free_extent_buffer(eb);
- continue;
- }
- ret = write_one_eb(eb, fs_info, wbc, &epd);
- if (ret) {
- done = 1;
- free_extent_buffer(eb);
- break;
- }
- free_extent_buffer(eb);
- nr_to_write_done = wbc->nr_to_write <= 0;
- }
- pagevec_release(&pvec);
- cond_resched();
- }
- if (!scanned && !done) {
- scanned = 1;
- index = 0;
- goto retry;
- }
- flush_write_bio(&epd);
- return ret;
- }
- /**
- * write_cache_pages - walk the list of dirty pages of the given address space and write all of them.
- * @mapping: address space structure to write
- * @wbc: subtract the number of written pages from *@wbc->nr_to_write
- * @writepage: function called for each page
- * @data: data passed to writepage function
- *
- * If a page is already under I/O, write_cache_pages() skips it, even
- * if it's dirty. This is desirable behaviour for memory-cleaning writeback,
- * but it is INCORRECT for data-integrity system calls such as fsync(). fsync()
- * and msync() need to guarantee that all the data which was dirty at the time
- * the call was made get new I/O started against them. If wbc->sync_mode is
- * WB_SYNC_ALL then we were called for data integrity and we must wait for
- * existing IO to complete.
- */
- static int extent_write_cache_pages(struct extent_io_tree *tree,
- struct address_space *mapping,
- struct writeback_control *wbc,
- writepage_t writepage, void *data,
- void (*flush_fn)(void *))
- {
- int ret = 0;
- int done = 0;
- int nr_to_write_done = 0;
- struct pagevec pvec;
- int nr_pages;
- pgoff_t index;
- pgoff_t end;
- int scanned = 0;
- int tag;
- pagevec_init(&pvec, 0);
- if (wbc->range_cyclic) {
- index = mapping->writeback_index;
- end = -1;
- } else {
- index = wbc->range_start >> PAGE_CACHE_SHIFT;
- end = wbc->range_end >> PAGE_CACHE_SHIFT;
- scanned = 1;
- }
- if (wbc->sync_mode == WB_SYNC_ALL)
- tag = PAGECACHE_TAG_TOWRITE;
- else
- tag = PAGECACHE_TAG_DIRTY;
- retry:
- if (wbc->sync_mode == WB_SYNC_ALL)
- tag_pages_for_writeback(mapping, index, end);
- while (!done && !nr_to_write_done && (index <= end) &&
- (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, tag,
- min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1))) {
- unsigned i;
- scanned = 1;
- for (i = 0; i < nr_pages; i++) {
- struct page *page = pvec.pages[i];
- if (tree->ops &&
- tree->ops->write_cache_pages_lock_hook) {
- tree->ops->write_cache_pages_lock_hook(page,
- data, flush_fn);
- } else {
- if (!trylock_page(page)) {
- flush_fn(data);
- lock_page(page);
- }
- }
- if (unlikely(page->mapping != mapping)) {
- unlock_page(page);
- continue;
- }
- if (!wbc->range_cyclic && page->index > end) {
- done = 1;
- unlock_page(page);
- continue;
- }
- if (wbc->sync_mode != WB_SYNC_NONE) {
- if (PageWriteback(page))
- flush_fn(data);
- wait_on_page_writeback(page);
- }
- if (PageWriteback(page) ||
- !clear_page_dirty_for_io(page)) {
- unlock_page(page);
- continue;
- }
- ret = (*writepage)(page, wbc, data);
- if (unlikely(ret == AOP_WRITEPAGE_ACTIVATE)) {
- unlock_page(page);
- ret = 0;
- }
- if (ret)
- done = 1;
- nr_to_write_done = wbc->nr_to_write <= 0;
- }
- pagevec_release(&pvec);
- cond_resched();
- }
- if (!scanned && !done) {
- scanned = 1;
- index = 0;
- goto retry;
- }
- return ret;
- }
- static void flush_epd_write_bio(struct extent_page_data *epd)
- {
- if (epd->bio) {
- int rw = WRITE;
- int ret;
- if (epd->sync_io)
- rw = WRITE_SYNC;
- ret = submit_one_bio(rw, epd->bio, 0, 0);
- BUG_ON(ret < 0);
- epd->bio = NULL;
- }
- }
- static noinline void flush_write_bio(void *data)
- {
- struct extent_page_data *epd = data;
- flush_epd_write_bio(epd);
- }
- int extent_write_full_page(struct extent_io_tree *tree, struct page *page,
- get_extent_t *get_extent,
- struct writeback_control *wbc)
- {
- int ret;
- struct extent_page_data epd = {
- .bio = NULL,
- .tree = tree,
- .get_extent = get_extent,
- .extent_locked = 0,
- .sync_io = wbc->sync_mode == WB_SYNC_ALL,
- };
- ret = __extent_writepage(page, wbc, &epd);
- flush_epd_write_bio(&epd);
- return ret;
- }
- int extent_write_locked_range(struct extent_io_tree *tree, struct inode *inode,
- u64 start, u64 end, get_extent_t *get_extent,
- int mode)
- {
- int ret = 0;
- struct address_space *mapping = inode->i_mapping;
- struct page *page;
- unsigned long nr_pages = (end - start + PAGE_CACHE_SIZE) >>
- PAGE_CACHE_SHIFT;
- struct extent_page_data epd = {
- .bio = NULL,
- .tree = tree,
- .get_extent = get_extent,
- .extent_locked = 1,
- .sync_io = mode == WB_SYNC_ALL,
- };
- struct writeback_control wbc_writepages = {
- .sync_mode = mode,
- .nr_to_write = nr_pages * 2,
- .range_start = start,
- .range_end = end + 1,
- };
- while (start <= end) {
- page = find_get_page(mapping, start >> PAGE_CACHE_SHIFT);
- if (clear_page_dirty_for_io(page))
- ret = __extent_writepage(page, &wbc_writepages, &epd);
- else {
- if (tree->ops && tree->ops->writepage_end_io_hook)
- tree->ops->writepage_end_io_hook(page, start,
- start + PAGE_CACHE_SIZE - 1,
- NULL, 1);
- unlock_page(page);
- }
- page_cache_release(page);
- start += PAGE_CACHE_SIZE;
- }
- flush_epd_write_bio(&epd);
- return ret;
- }
- int extent_writepages(struct extent_io_tree *tree,
- struct address_space *mapping,
- get_extent_t *get_extent,
- struct writeback_control *wbc)
- {
- int ret = 0;
- struct extent_page_data epd = {
- .bio = NULL,
- .tree = tree,
- .get_extent = get_extent,
- .extent_locked = 0,
- .sync_io = wbc->sync_mode == WB_SYNC_ALL,
- };
- ret = extent_write_cache_pages(tree, mapping, wbc,
- __extent_writepage, &epd,
- flush_write_bio);
- flush_epd_write_bio(&epd);
- return ret;
- }
- int extent_readpages(struct extent_io_tree *tree,
- struct address_space *mapping,
- struct list_head *pages, unsigned nr_pages,
- get_extent_t get_extent)
- {
- struct bio *bio = NULL;
- unsigned page_idx;
- unsigned long bio_flags = 0;
- for (page_idx = 0; page_idx < nr_pages; page_idx++) {
- struct page *page = list_entry(pages->prev, struct page, lru);
- prefetchw(&page->flags);
- list_del(&page->lru);
- if (!add_to_page_cache_lru(page, mapping,
- page->index, GFP_NOFS)) {
- __extent_read_full_page(tree, page, get_extent,
- &bio, 0, &bio_flags);
- }
- page_cache_release(page);
- }
- BUG_ON(!list_empty(pages));
- if (bio)
- return submit_one_bio(READ, bio, 0, bio_flags);
- return 0;
- }
- int extent_invalidatepage(struct extent_io_tree *tree,
- struct page *page, unsigned long offset)
- {
- struct extent_state *cached_state = NULL;
- u64 start = ((u64)page->index << PAGE_CACHE_SHIFT);
- u64 end = start + PAGE_CACHE_SIZE - 1;
- size_t blocksize = page->mapping->host->i_sb->s_blocksize;
- start += (offset + blocksize - 1) & ~(blocksize - 1);
- if (start > end)
- return 0;
- lock_extent_bits(tree, start, end, 0, &cached_state);
- wait_on_page_writeback(page);
- clear_extent_bit(tree, start, end,
- EXTENT_LOCKED | EXTENT_DIRTY | EXTENT_DELALLOC |
- EXTENT_DO_ACCOUNTING,
- 1, 1, &cached_state, GFP_NOFS);
- return 0;
- }
- int try_release_extent_state(struct extent_map_tree *map,
- struct extent_io_tree *tree, struct page *page,
- gfp_t mask)
- {
- u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
- u64 end = start + PAGE_CACHE_SIZE - 1;
- int ret = 1;
- if (test_range_bit(tree, start, end,
- EXTENT_IOBITS, 0, NULL))
- ret = 0;
- else {
- if ((mask & GFP_NOFS) == GFP_NOFS)
- mask = GFP_NOFS;
- ret = clear_extent_bit(tree, start, end,
- ~(EXTENT_LOCKED | EXTENT_NODATASUM),
- 0, 0, NULL, mask);
- if (ret < 0)
- ret = 0;
- else
- ret = 1;
- }
- return ret;
- }
- int try_release_extent_mapping(struct extent_map_tree *map,
- struct extent_io_tree *tree, struct page *page,
- gfp_t mask)
- {
- struct extent_map *em;
- u64 start = (u64)page->index << PAGE_CACHE_SHIFT;
- u64 end = start + PAGE_CACHE_SIZE - 1;
- if ((mask & __GFP_WAIT) &&
- page->mapping->host->i_size > 16 * 1024 * 1024) {
- u64 len;
- while (start <= end) {
- len = end - start + 1;
- write_lock(&map->lock);
- em = lookup_extent_mapping(map, start, len);
- if (!em) {
- write_unlock(&map->lock);
- break;
- }
- if (test_bit(EXTENT_FLAG_PINNED, &em->flags) ||
- em->start != start) {
- write_unlock(&map->lock);
- free_extent_map(em);
- break;
- }
- if (!test_range_bit(tree, em->start,
- extent_map_end(em) - 1,
- EXTENT_LOCKED | EXTENT_WRITEBACK,
- 0, NULL)) {
- remove_extent_mapping(map, em);
-
- free_extent_map(em);
- }
- start = extent_map_end(em);
- write_unlock(&map->lock);
-
- free_extent_map(em);
- }
- }
- return try_release_extent_state(map, tree, page, mask);
- }
- static struct extent_map *get_extent_skip_holes(struct inode *inode,
- u64 offset,
- u64 last,
- get_extent_t *get_extent)
- {
- u64 sectorsize = BTRFS_I(inode)->root->sectorsize;
- struct extent_map *em;
- u64 len;
- if (offset >= last)
- return NULL;
- while(1) {
- len = last - offset;
- if (len == 0)
- break;
- len = (len + sectorsize - 1) & ~(sectorsize - 1);
- em = get_extent(inode, NULL, 0, offset, len, 0);
- if (IS_ERR_OR_NULL(em))
- return em;
-
- if (!test_bit(EXTENT_FLAG_VACANCY, &em->flags) &&
- em->block_start != EXTENT_MAP_HOLE) {
- return em;
- }
-
- offset = extent_map_end(em);
- free_extent_map(em);
- if (offset >= last)
- break;
- }
- return NULL;
- }
- int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
- __u64 start, __u64 len, get_extent_t *get_extent)
- {
- int ret = 0;
- u64 off = start;
- u64 max = start + len;
- u32 flags = 0;
- u32 found_type;
- u64 last;
- u64 last_for_get_extent = 0;
- u64 disko = 0;
- u64 isize = i_size_read(inode);
- struct btrfs_key found_key;
- struct extent_map *em = NULL;
- struct extent_state *cached_state = NULL;
- struct btrfs_path *path;
- struct btrfs_file_extent_item *item;
- int end = 0;
- u64 em_start = 0;
- u64 em_len = 0;
- u64 em_end = 0;
- unsigned long emflags;
- if (len == 0)
- return -EINVAL;
- path = btrfs_alloc_path();
- if (!path)
- return -ENOMEM;
- path->leave_spinning = 1;
- start = ALIGN(start, BTRFS_I(inode)->root->sectorsize);
- len = ALIGN(len, BTRFS_I(inode)->root->sectorsize);
- ret = btrfs_lookup_file_extent(NULL, BTRFS_I(inode)->root,
- path, btrfs_ino(inode), -1, 0);
- if (ret < 0) {
- btrfs_free_path(path);
- return ret;
- }
- WARN_ON(!ret);
- path->slots[0]--;
- item = btrfs_item_ptr(path->nodes[0], path->slots[0],
- struct btrfs_file_extent_item);
- btrfs_item_key_to_cpu(path->nodes[0], &found_key, path->slots[0]);
- found_type = btrfs_key_type(&found_key);
-
- if (found_key.objectid != btrfs_ino(inode) ||
- found_type != BTRFS_EXTENT_DATA_KEY) {
-
- last = (u64)-1;
- last_for_get_extent = isize;
- } else {
- last = found_key.offset;
- last_for_get_extent = last + 1;
- }
- btrfs_free_path(path);
- if (last < isize) {
- last = (u64)-1;
- last_for_get_extent = isize;
- }
- lock_extent_bits(&BTRFS_I(inode)->io_tree, start, start + len, 0,
- &cached_state);
- em = get_extent_skip_holes(inode, start, last_for_get_extent,
- get_extent);
- if (!em)
- goto out;
- if (IS_ERR(em)) {
- ret = PTR_ERR(em);
- goto out;
- }
- while (!end) {
- u64 offset_in_extent;
-
- if (em->start >= max || extent_map_end(em) < off)
- break;
- em_start = max(em->start, off);
- offset_in_extent = em_start - em->start;
- em_end = extent_map_end(em);
- em_len = em_end - em_start;
- emflags = em->flags;
- disko = 0;
- flags = 0;
- off = extent_map_end(em);
- if (off >= max)
- end = 1;
- if (em->block_start == EXTENT_MAP_LAST_BYTE) {
- end = 1;
- flags |= FIEMAP_EXTENT_LAST;
- } else if (em->block_start == EXTENT_MAP_INLINE) {
- flags |= (FIEMAP_EXTENT_DATA_INLINE |
- FIEMAP_EXTENT_NOT_ALIGNED);
- } else if (em->block_start == EXTENT_MAP_DELALLOC) {
- flags |= (FIEMAP_EXTENT_DELALLOC |
- FIEMAP_EXTENT_UNKNOWN);
- } else {
- disko = em->block_start + offset_in_extent;
- }
- if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags))
- flags |= FIEMAP_EXTENT_ENCODED;
- free_extent_map(em);
- em = NULL;
- if ((em_start >= last) || em_len == (u64)-1 ||
- (last == (u64)-1 && isize <= em_end)) {
- flags |= FIEMAP_EXTENT_LAST;
- end = 1;
- }
-
- em = get_extent_skip_holes(inode, off, last_for_get_extent,
- get_extent);
- if (IS_ERR(em)) {
- ret = PTR_ERR(em);
- goto out;
- }
- if (!em) {
- flags |= FIEMAP_EXTENT_LAST;
- end = 1;
- }
- ret = fiemap_fill_next_extent(fieinfo, em_start, disko,
- em_len, flags);
- if (ret)
- goto out_free;
- }
- out_free:
- free_extent_map(em);
- out:
- unlock_extent_cached(&BTRFS_I(inode)->io_tree, start, start + len,
- &cached_state, GFP_NOFS);
- return ret;
- }
- inline struct page *extent_buffer_page(struct extent_buffer *eb,
- unsigned long i)
- {
- return eb->pages[i];
- }
- inline unsigned long num_extent_pages(u64 start, u64 len)
- {
- return ((start + len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT) -
- (start >> PAGE_CACHE_SHIFT);
- }
- static void __free_extent_buffer(struct extent_buffer *eb)
- {
- #if LEAK_DEBUG
- unsigned long flags;
- spin_lock_irqsave(&leak_lock, flags);
- list_del(&eb->leak_list);
- spin_unlock_irqrestore(&leak_lock, flags);
- #endif
- if (eb->pages && eb->pages != eb->inline_pages)
- kfree(eb->pages);
- kmem_cache_free(extent_buffer_cache, eb);
- }
- static struct extent_buffer *__alloc_extent_buffer(struct extent_io_tree *tree,
- u64 start,
- unsigned long len,
- gfp_t mask)
- {
- struct extent_buffer *eb = NULL;
- #if LEAK_DEBUG
- unsigned long flags;
- #endif
- eb = kmem_cache_zalloc(extent_buffer_cache, mask);
- if (eb == NULL)
- return NULL;
- eb->start = start;
- eb->len = len;
- eb->tree = tree;
- rwlock_init(&eb->lock);
- atomic_set(&eb->write_locks, 0);
- atomic_set(&eb->read_locks, 0);
- atomic_set(&eb->blocking_readers, 0);
- atomic_set(&eb->blocking_writers, 0);
- atomic_set(&eb->spinning_readers, 0);
- atomic_set(&eb->spinning_writers, 0);
- eb->lock_nested = 0;
- init_waitqueue_head(&eb->write_lock_wq);
- init_waitqueue_head(&eb->read_lock_wq);
- #if LEAK_DEBUG
- spin_lock_irqsave(&leak_lock, flags);
- list_add(&eb->leak_list, &buffers);
- spin_unlock_irqrestore(&leak_lock, flags);
- #endif
- spin_lock_init(&eb->refs_lock);
- atomic_set(&eb->refs, 1);
- atomic_set(&eb->io_pages, 0);
- if (len > MAX_INLINE_EXTENT_BUFFER_SIZE) {
- struct page **pages;
- int num_pages = (len + PAGE_CACHE_SIZE - 1) >>
- PAGE_CACHE_SHIFT;
- pages = kzalloc(num_pages, mask);
- if (!pages) {
- __free_extent_buffer(eb);
- return NULL;
- }
- eb->pages = pages;
- } else {
- eb->pages = eb->inline_pages;
- }
- return eb;
- }
- static int extent_buffer_under_io(struct extent_buffer *eb)
- {
- return (atomic_read(&eb->io_pages) ||
- test_bit(EXTENT_BUFFER_WRITEBACK, &eb->bflags) ||
- test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
- }
- static void btrfs_release_extent_buffer_page(struct extent_buffer *eb,
- unsigned long start_idx)
- {
- unsigned long index;
- struct page *page;
- BUG_ON(extent_buffer_under_io(eb));
- index = num_extent_pages(eb->start, eb->len);
- if (start_idx >= index)
- return;
- do {
- index--;
- page = extent_buffer_page(eb, index);
- if (page) {
- spin_lock(&page->mapping->private_lock);
- if (PagePrivate(page) &&
- page->private == (unsigned long)eb) {
- BUG_ON(test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags));
- BUG_ON(PageDirty(page));
- BUG_ON(PageWriteback(page));
- ClearPagePrivate(page);
- set_page_private(page, 0);
-
- page_cache_release(page);
- }
- spin_unlock(&page->mapping->private_lock);
-
- page_cache_release(page);
- }
- } while (index != start_idx);
- }
- static inline void btrfs_release_extent_buffer(struct extent_buffer *eb)
- {
- btrfs_release_extent_buffer_page(eb, 0);
- __free_extent_buffer(eb);
- }
- static void check_buffer_tree_ref(struct extent_buffer *eb)
- {
- if (!test_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags)) {
- atomic_inc(&eb->refs);
- if (test_and_set_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags))
- atomic_dec(&eb->refs);
- }
- }
- static void mark_extent_buffer_accessed(struct extent_buffer *eb)
- {
- unsigned long num_pages, i;
- check_buffer_tree_ref(eb);
- num_pages = num_extent_pages(eb->start, eb->len);
- for (i = 0; i < num_pages; i++) {
- struct page *p = extent_buffer_page(eb, i);
- mark_page_accessed(p);
- }
- }
- struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree,
- u64 start, unsigned long len)
- {
- unsigned long num_pages = num_extent_pages(start, len);
- unsigned long i;
- unsigned long index = start >> PAGE_CACHE_SHIFT;
- struct extent_buffer *eb;
- struct extent_buffer *exists = NULL;
- struct page *p;
- struct address_space *mapping = tree->mapping;
- int uptodate = 1;
- int ret;
- rcu_read_lock();
- eb = radix_tree_lookup(&tree->buffer, start >> PAGE_CACHE_SHIFT);
- if (eb && atomic_inc_not_zero(&eb->refs)) {
- rcu_read_unlock();
- mark_extent_buffer_accessed(eb);
- return eb;
- }
- rcu_read_unlock();
- eb = __alloc_extent_buffer(tree, start, len, GFP_NOFS);
- if (!eb)
- return NULL;
- for (i = 0; i < num_pages; i++, index++) {
- p = find_or_create_page(mapping, index, GFP_NOFS);
- if (!p) {
- WARN_ON(1);
- goto free_eb;
- }
- spin_lock(&mapping->private_lock);
- if (PagePrivate(p)) {
- exists = (struct extent_buffer *)p->private;
- if (atomic_inc_not_zero(&exists->refs)) {
- spin_unlock(&mapping->private_lock);
- unlock_page(p);
- page_cache_release(p);
- mark_extent_buffer_accessed(exists);
- goto free_eb;
- }
- ClearPagePrivate(p);
- WARN_ON(PageDirty(p));
- page_cache_release(p);
- }
- attach_extent_buffer_page(eb, p);
- spin_unlock(&mapping->private_lock);
- WARN_ON(PageDirty(p));
- mark_page_accessed(p);
- eb->pages[i] = p;
- if (!PageUptodate(p))
- uptodate = 0;
- }
- if (uptodate)
- set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
- again:
- ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
- if (ret)
- goto free_eb;
- spin_lock(&tree->buffer_lock);
- ret = radix_tree_insert(&tree->buffer, start >> PAGE_CACHE_SHIFT, eb);
- if (ret == -EEXIST) {
- exists = radix_tree_lookup(&tree->buffer,
- start >> PAGE_CACHE_SHIFT);
- if (!atomic_inc_not_zero(&exists->refs)) {
- spin_unlock(&tree->buffer_lock);
- radix_tree_preload_end();
- exists = NULL;
- goto again;
- }
- spin_unlock(&tree->buffer_lock);
- radix_tree_preload_end();
- mark_extent_buffer_accessed(exists);
- goto free_eb;
- }
-
- spin_lock(&eb->refs_lock);
- check_buffer_tree_ref(eb);
- spin_unlock(&eb->refs_lock);
- spin_unlock(&tree->buffer_lock);
- radix_tree_preload_end();
- SetPageChecked(eb->pages[0]);
- for (i = 1; i < num_pages; i++) {
- p = extent_buffer_page(eb, i);
- ClearPageChecked(p);
- unlock_page(p);
- }
- unlock_page(eb->pages[0]);
- return eb;
- free_eb:
- for (i = 0; i < num_pages; i++) {
- if (eb->pages[i])
- unlock_page(eb->pages[i]);
- }
- WARN_ON(!atomic_dec_and_test(&eb->refs));
- btrfs_release_extent_buffer(eb);
- return exists;
- }
- struct extent_buffer *find_extent_buffer(struct extent_io_tree *tree,
- u64 start, unsigned long len)
- {
- struct extent_buffer *eb;
- rcu_read_lock();
- eb = radix_tree_lookup(&tree->buffer, start >> PAGE_CACHE_SHIFT);
- if (eb && atomic_inc_not_zero(&eb->refs)) {
- rcu_read_unlock();
- mark_extent_buffer_accessed(eb);
- return eb;
- }
- rcu_read_unlock();
- return NULL;
- }
- static inline void btrfs_release_extent_buffer_rcu(struct rcu_head *head)
- {
- struct extent_buffer *eb =
- container_of(head, struct extent_buffer, rcu_head);
- __free_extent_buffer(eb);
- }
- static void release_extent_buffer(struct extent_buffer *eb, gfp_t mask)
- {
- WARN_ON(atomic_read(&eb->refs) == 0);
- if (atomic_dec_and_test(&eb->refs)) {
- struct extent_io_tree *tree = eb->tree;
- spin_unlock(&eb->refs_lock);
- spin_lock(&tree->buffer_lock);
- radix_tree_delete(&tree->buffer,
- eb->start >> PAGE_CACHE_SHIFT);
- spin_unlock(&tree->buffer_lock);
-
- btrfs_release_extent_buffer_page(eb, 0);
- call_rcu(&eb->rcu_head, btrfs_release_extent_buffer_rcu);
- return;
- }
- spin_unlock(&eb->refs_lock);
- }
- void free_extent_buffer(struct extent_buffer *eb)
- {
- if (!eb)
- return;
- spin_lock(&eb->refs_lock);
- if (atomic_read(&eb->refs) == 2 &&
- test_bit(EXTENT_BUFFER_STALE, &eb->bflags) &&
- !extent_buffer_under_io(eb) &&
- test_and_clear_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags))
- atomic_dec(&eb->refs);
- release_extent_buffer(eb, GFP_ATOMIC);
- }
- void free_extent_buffer_stale(struct extent_buffer *eb)
- {
- if (!eb)
- return;
- spin_lock(&eb->refs_lock);
- set_bit(EXTENT_BUFFER_STALE, &eb->bflags);
- if (atomic_read(&eb->refs) == 2 && !extent_buffer_under_io(eb) &&
- test_and_clear_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags))
- atomic_dec(&eb->refs);
- release_extent_buffer(eb, GFP_NOFS);
- }
- void clear_extent_buffer_dirty(struct extent_buffer *eb)
- {
- unsigned long i;
- unsigned long num_pages;
- struct page *page;
- num_pages = num_extent_pages(eb->start, eb->len);
- for (i = 0; i < num_pages; i++) {
- page = extent_buffer_page(eb, i);
- if (!PageDirty(page))
- continue;
- lock_page(page);
- WARN_ON(!PagePrivate(page));
- clear_page_dirty_for_io(page);
- spin_lock_irq(&page->mapping->tree_lock);
- if (!PageDirty(page)) {
- radix_tree_tag_clear(&page->mapping->page_tree,
- page_index(page),
- PAGECACHE_TAG_DIRTY);
- }
- spin_unlock_irq(&page->mapping->tree_lock);
- ClearPageError(page);
- unlock_page(page);
- }
- WARN_ON(atomic_read(&eb->refs) == 0);
- }
- int set_extent_buffer_dirty(struct extent_buffer *eb)
- {
- unsigned long i;
- unsigned long num_pages;
- int was_dirty = 0;
- check_buffer_tree_ref(eb);
- was_dirty = test_and_set_bit(EXTENT_BUFFER_DIRTY, &eb->bflags);
- num_pages = num_extent_pages(eb->start, eb->len);
- WARN_ON(atomic_read(&eb->refs) == 0);
- WARN_ON(!test_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags));
- for (i = 0; i < num_pages; i++)
- set_page_dirty(extent_buffer_page(eb, i));
- return was_dirty;
- }
- static int range_straddles_pages(u64 start, u64 len)
- {
- if (len < PAGE_CACHE_SIZE)
- return 1;
- if (start & (PAGE_CACHE_SIZE - 1))
- return 1;
- if ((start + len) & (PAGE_CACHE_SIZE - 1))
- return 1;
- return 0;
- }
- int clear_extent_buffer_uptodate(struct extent_buffer *eb)
- {
- unsigned long i;
- struct page *page;
- unsigned long num_pages;
- clear_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
- num_pages = num_extent_pages(eb->start, eb->len);
- for (i = 0; i < num_pages; i++) {
- page = extent_buffer_page(eb, i);
- if (page)
- ClearPageUptodate(page);
- }
- return 0;
- }
- int set_extent_buffer_uptodate(struct extent_buffer *eb)
- {
- unsigned long i;
- struct page *page;
- unsigned long num_pages;
- set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
- num_pages = num_extent_pages(eb->start, eb->len);
- for (i = 0; i < num_pages; i++) {
- page = extent_buffer_page(eb, i);
- SetPageUptodate(page);
- }
- return 0;
- }
- int extent_range_uptodate(struct extent_io_tree *tree,
- u64 start, u64 end)
- {
- struct page *page;
- int ret;
- int pg_uptodate = 1;
- int uptodate;
- unsigned long index;
- if (range_straddles_pages(start, end - start + 1)) {
- ret = test_range_bit(tree, start, end,
- EXTENT_UPTODATE, 1, NULL);
- if (ret)
- return 1;
- }
- while (start <= end) {
- index = start >> PAGE_CACHE_SHIFT;
- page = find_get_page(tree->mapping, index);
- if (!page)
- return 1;
- uptodate = PageUptodate(page);
- page_cache_release(page);
- if (!uptodate) {
- pg_uptodate = 0;
- break;
- }
- start += PAGE_CACHE_SIZE;
- }
- return pg_uptodate;
- }
- int extent_buffer_uptodate(struct extent_buffer *eb)
- {
- return test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
- }
- int read_extent_buffer_pages(struct extent_io_tree *tree,
- struct extent_buffer *eb, u64 start, int wait,
- get_extent_t *get_extent, int mirror_num)
- {
- unsigned long i;
- unsigned long start_i;
- struct page *page;
- int err;
- int ret = 0;
- int locked_pages = 0;
- int all_uptodate = 1;
- unsigned long num_pages;
- unsigned long num_reads = 0;
- struct bio *bio = NULL;
- unsigned long bio_flags = 0;
- if (test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags))
- return 0;
- if (start) {
- WARN_ON(start < eb->start);
- start_i = (start >> PAGE_CACHE_SHIFT) -
- (eb->start >> PAGE_CACHE_SHIFT);
- } else {
- start_i = 0;
- }
- num_pages = num_extent_pages(eb->start, eb->len);
- for (i = start_i; i < num_pages; i++) {
- page = extent_buffer_page(eb, i);
- if (wait == WAIT_NONE) {
- if (!trylock_page(page))
- goto unlock_exit;
- } else {
- lock_page(page);
- }
- locked_pages++;
- if (!PageUptodate(page)) {
- num_reads++;
- all_uptodate = 0;
- }
- }
- if (all_uptodate) {
- if (start_i == 0)
- set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags);
- goto unlock_exit;
- }
- clear_bit(EXTENT_BUFFER_IOERR, &eb->bflags);
- eb->read_mirror = 0;
- atomic_set(&eb->io_pages, num_reads);
- for (i = start_i; i < num_pages; i++) {
- page = extent_buffer_page(eb, i);
- if (!PageUptodate(page)) {
- ClearPageError(page);
- err = __extent_read_full_page(tree, page,
- get_extent, &bio,
- mirror_num, &bio_flags);
- if (err)
- ret = err;
- } else {
- unlock_page(page);
- }
- }
- if (bio) {
- err = submit_one_bio(READ, bio, mirror_num, bio_flags);
- if (err)
- return err;
- }
- if (ret || wait != WAIT_COMPLETE)
- return ret;
- for (i = start_i; i < num_pages; i++) {
- page = extent_buffer_page(eb, i);
- wait_on_page_locked(page);
- if (!PageUptodate(page))
- ret = -EIO;
- }
- return ret;
- unlock_exit:
- i = start_i;
- while (locked_pages > 0) {
- page = extent_buffer_page(eb, i);
- i++;
- unlock_page(page);
- locked_pages--;
- }
- return ret;
- }
- void read_extent_buffer(struct extent_buffer *eb, void *dstv,
- unsigned long start,
- unsigned long len)
- {
- size_t cur;
- size_t offset;
- struct page *page;
- char *kaddr;
- char *dst = (char *)dstv;
- size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1);
- unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT;
- WARN_ON(start > eb->len);
- WARN_ON(start + len > eb->start + eb->len);
- offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1);
- while (len > 0) {
- page = extent_buffer_page(eb, i);
- cur = min(len, (PAGE_CACHE_SIZE - offset));
- kaddr = page_address(page);
- memcpy(dst, kaddr + offset, cur);
- dst += cur;
- len -= cur;
- offset = 0;
- i++;
- }
- }
- int map_private_extent_buffer(struct extent_buffer *eb, unsigned long start,
- unsigned long min_len, char **map,
- unsigned long *map_start,
- unsigned long *map_len)
- {
- size_t offset = start & (PAGE_CACHE_SIZE - 1);
- char *kaddr;
- struct page *p;
- size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1);
- unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT;
- unsigned long end_i = (start_offset + start + min_len - 1) >>
- PAGE_CACHE_SHIFT;
- if (i != end_i)
- return -EINVAL;
- if (i == 0) {
- offset = start_offset;
- *map_start = 0;
- } else {
- offset = 0;
- *map_start = ((u64)i << PAGE_CACHE_SHIFT) - start_offset;
- }
- if (start + min_len > eb->len) {
- printk(KERN_ERR "btrfs bad mapping eb start %llu len %lu, "
- "wanted %lu %lu\n", (unsigned long long)eb->start,
- eb->len, start, min_len);
- WARN_ON(1);
- return -EINVAL;
- }
- p = extent_buffer_page(eb, i);
- kaddr = page_address(p);
- *map = kaddr + offset;
- *map_len = PAGE_CACHE_SIZE - offset;
- return 0;
- }
- int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv,
- unsigned long start,
- unsigned long len)
- {
- size_t cur;
- size_t offset;
- struct page *page;
- char *kaddr;
- char *ptr = (char *)ptrv;
- size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1);
- unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT;
- int ret = 0;
- WARN_ON(start > eb->len);
- WARN_ON(start + len > eb->start + eb->len);
- offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1);
- while (len > 0) {
- page = extent_buffer_page(eb, i);
- cur = min(len, (PAGE_CACHE_SIZE - offset));
- kaddr = page_address(page);
- ret = memcmp(ptr, kaddr + offset, cur);
- if (ret)
- break;
- ptr += cur;
- len -= cur;
- offset = 0;
- i++;
- }
- return ret;
- }
- void write_extent_buffer(struct extent_buffer *eb, const void *srcv,
- unsigned long start, unsigned long len)
- {
- size_t cur;
- size_t offset;
- struct page *page;
- char *kaddr;
- char *src = (char *)srcv;
- size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1);
- unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT;
- WARN_ON(start > eb->len);
- WARN_ON(start + len > eb->start + eb->len);
- offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1);
- while (len > 0) {
- page = extent_buffer_page(eb, i);
- WARN_ON(!PageUptodate(page));
- cur = min(len, PAGE_CACHE_SIZE - offset);
- kaddr = page_address(page);
- memcpy(kaddr + offset, src, cur);
- src += cur;
- len -= cur;
- offset = 0;
- i++;
- }
- }
- void memset_extent_buffer(struct extent_buffer *eb, char c,
- unsigned long start, unsigned long len)
- {
- size_t cur;
- size_t offset;
- struct page *page;
- char *kaddr;
- size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1);
- unsigned long i = (start_offset + start) >> PAGE_CACHE_SHIFT;
- WARN_ON(start > eb->len);
- WARN_ON(start + len > eb->start + eb->len);
- offset = (start_offset + start) & ((unsigned long)PAGE_CACHE_SIZE - 1);
- while (len > 0) {
- page = extent_buffer_page(eb, i);
- WARN_ON(!PageUptodate(page));
- cur = min(len, PAGE_CACHE_SIZE - offset);
- kaddr = page_address(page);
- memset(kaddr + offset, c, cur);
- len -= cur;
- offset = 0;
- i++;
- }
- }
- void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src,
- unsigned long dst_offset, unsigned long src_offset,
- unsigned long len)
- {
- u64 dst_len = dst->len;
- size_t cur;
- size_t offset;
- struct page *page;
- char *kaddr;
- size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1);
- unsigned long i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT;
- WARN_ON(src->len != dst_len);
- offset = (start_offset + dst_offset) &
- ((unsigned long)PAGE_CACHE_SIZE - 1);
- while (len > 0) {
- page = extent_buffer_page(dst, i);
- WARN_ON(!PageUptodate(page));
- cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - offset));
- kaddr = page_address(page);
- read_extent_buffer(src, kaddr + offset, src_offset, cur);
- src_offset += cur;
- len -= cur;
- offset = 0;
- i++;
- }
- }
- static void move_pages(struct page *dst_page, struct page *src_page,
- unsigned long dst_off, unsigned long src_off,
- unsigned long len)
- {
- char *dst_kaddr = page_address(dst_page);
- if (dst_page == src_page) {
- memmove(dst_kaddr + dst_off, dst_kaddr + src_off, len);
- } else {
- char *src_kaddr = page_address(src_page);
- char *p = dst_kaddr + dst_off + len;
- char *s = src_kaddr + src_off + len;
- while (len--)
- *--p = *--s;
- }
- }
- static inline bool areas_overlap(unsigned long src, unsigned long dst, unsigned long len)
- {
- unsigned long distance = (src > dst) ? src - dst : dst - src;
- return distance < len;
- }
- static void copy_pages(struct page *dst_page, struct page *src_page,
- unsigned long dst_off, unsigned long src_off,
- unsigned long len)
- {
- char *dst_kaddr = page_address(dst_page);
- char *src_kaddr;
- int must_memmove = 0;
- if (dst_page != src_page) {
- src_kaddr = page_address(src_page);
- } else {
- src_kaddr = dst_kaddr;
- if (areas_overlap(src_off, dst_off, len))
- must_memmove = 1;
- }
- if (must_memmove)
- memmove(dst_kaddr + dst_off, src_kaddr + src_off, len);
- else
- memcpy(dst_kaddr + dst_off, src_kaddr + src_off, len);
- }
- void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
- unsigned long src_offset, unsigned long len)
- {
- size_t cur;
- size_t dst_off_in_page;
- size_t src_off_in_page;
- size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1);
- unsigned long dst_i;
- unsigned long src_i;
- if (src_offset + len > dst->len) {
- printk(KERN_ERR "btrfs memmove bogus src_offset %lu move "
- "len %lu dst len %lu\n", src_offset, len, dst->len);
- BUG_ON(1);
- }
- if (dst_offset + len > dst->len) {
- printk(KERN_ERR "btrfs memmove bogus dst_offset %lu move "
- "len %lu dst len %lu\n", dst_offset, len, dst->len);
- BUG_ON(1);
- }
- while (len > 0) {
- dst_off_in_page = (start_offset + dst_offset) &
- ((unsigned long)PAGE_CACHE_SIZE - 1);
- src_off_in_page = (start_offset + src_offset) &
- ((unsigned long)PAGE_CACHE_SIZE - 1);
- dst_i = (start_offset + dst_offset) >> PAGE_CACHE_SHIFT;
- src_i = (start_offset + src_offset) >> PAGE_CACHE_SHIFT;
- cur = min(len, (unsigned long)(PAGE_CACHE_SIZE -
- src_off_in_page));
- cur = min_t(unsigned long, cur,
- (unsigned long)(PAGE_CACHE_SIZE - dst_off_in_page));
- copy_pages(extent_buffer_page(dst, dst_i),
- extent_buffer_page(dst, src_i),
- dst_off_in_page, src_off_in_page, cur);
- src_offset += cur;
- dst_offset += cur;
- len -= cur;
- }
- }
- void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset,
- unsigned long src_offset, unsigned long len)
- {
- size_t cur;
- size_t dst_off_in_page;
- size_t src_off_in_page;
- unsigned long dst_end = dst_offset + len - 1;
- unsigned long src_end = src_offset + len - 1;
- size_t start_offset = dst->start & ((u64)PAGE_CACHE_SIZE - 1);
- unsigned long dst_i;
- unsigned long src_i;
- if (src_offset + len > dst->len) {
- printk(KERN_ERR "btrfs memmove bogus src_offset %lu move "
- "len %lu len %lu\n", src_offset, len, dst->len);
- BUG_ON(1);
- }
- if (dst_offset + len > dst->len) {
- printk(KERN_ERR "btrfs memmove bogus dst_offset %lu move "
- "len %lu len %lu\n", dst_offset, len, dst->len);
- BUG_ON(1);
- }
- if (dst_offset < src_offset) {
- memcpy_extent_buffer(dst, dst_offset, src_offset, len);
- return;
- }
- while (len > 0) {
- dst_i = (start_offset + dst_end) >> PAGE_CACHE_SHIFT;
- src_i = (start_offset + src_end) >> PAGE_CACHE_SHIFT;
- dst_off_in_page = (start_offset + dst_end) &
- ((unsigned long)PAGE_CACHE_SIZE - 1);
- src_off_in_page = (start_offset + src_end) &
- ((unsigned long)PAGE_CACHE_SIZE - 1);
- cur = min_t(unsigned long, len, src_off_in_page + 1);
- cur = min(cur, dst_off_in_page + 1);
- move_pages(extent_buffer_page(dst, dst_i),
- extent_buffer_page(dst, src_i),
- dst_off_in_page - cur + 1,
- src_off_in_page - cur + 1, cur);
- dst_end -= cur;
- src_end -= cur;
- len -= cur;
- }
- }
- int try_release_extent_buffer(struct page *page, gfp_t mask)
- {
- struct extent_buffer *eb;
- spin_lock(&page->mapping->private_lock);
- if (!PagePrivate(page)) {
- spin_unlock(&page->mapping->private_lock);
- return 1;
- }
- eb = (struct extent_buffer *)page->private;
- BUG_ON(!eb);
- spin_lock(&eb->refs_lock);
- if (atomic_read(&eb->refs) != 1 || extent_buffer_under_io(eb)) {
- spin_unlock(&eb->refs_lock);
- spin_unlock(&page->mapping->private_lock);
- return 0;
- }
- spin_unlock(&page->mapping->private_lock);
- if ((mask & GFP_NOFS) == GFP_NOFS)
- mask = GFP_NOFS;
- if (!test_and_clear_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags)) {
- spin_unlock(&eb->refs_lock);
- return 0;
- }
- release_extent_buffer(eb, mask);
- return 1;
- }