blob: 4e03a6d3aa324be2d0ff259e256e5d9956b35fbf [file] [log] [blame]
// SPDX-License-Identifier: 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/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 <linux/fsverity.h>
#include "misc.h"
#include "extent_io.h"
#include "extent-io-tree.h"
#include "extent_map.h"
#include "ctree.h"
#include "btrfs_inode.h"
#include "volumes.h"
#include "check-integrity.h"
#include "locking.h"
#include "rcu-string.h"
#include "backref.h"
#include "disk-io.h"
#include "subpage.h"
#include "zoned.h"
#include "block-group.h"
static struct kmem_cache *extent_state_cache;
static struct kmem_cache *extent_buffer_cache;
static struct bio_set btrfs_bioset;
static inline bool extent_state_in_tree(const struct extent_state *state)
{
return !RB_EMPTY_NODE(&state->rb_node);
}
#ifdef CONFIG_BTRFS_DEBUG
static LIST_HEAD(states);
static DEFINE_SPINLOCK(leak_lock);
static inline void btrfs_leak_debug_add(spinlock_t *lock,
struct list_head *new,
struct list_head *head)
{
unsigned long flags;
spin_lock_irqsave(lock, flags);
list_add(new, head);
spin_unlock_irqrestore(lock, flags);
}
static inline void btrfs_leak_debug_del(spinlock_t *lock,
struct list_head *entry)
{
unsigned long flags;
spin_lock_irqsave(lock, flags);
list_del(entry);
spin_unlock_irqrestore(lock, flags);
}
void btrfs_extent_buffer_leak_debug_check(struct btrfs_fs_info *fs_info)
{
struct extent_buffer *eb;
unsigned long flags;
/*
* If we didn't get into open_ctree our allocated_ebs will not be
* initialized, so just skip this.
*/
if (!fs_info->allocated_ebs.next)
return;
spin_lock_irqsave(&fs_info->eb_leak_lock, flags);
while (!list_empty(&fs_info->allocated_ebs)) {
eb = list_first_entry(&fs_info->allocated_ebs,
struct extent_buffer, leak_list);
pr_err(
"BTRFS: buffer leak start %llu len %lu refs %d bflags %lu owner %llu\n",
eb->start, eb->len, atomic_read(&eb->refs), eb->bflags,
btrfs_header_owner(eb));
list_del(&eb->leak_list);
kmem_cache_free(extent_buffer_cache, eb);
}
spin_unlock_irqrestore(&fs_info->eb_leak_lock, flags);
}
static inline void btrfs_extent_state_leak_debug_check(void)
{
struct extent_state *state;
while (!list_empty(&states)) {
state = list_entry(states.next, struct extent_state, leak_list);
pr_err("BTRFS: state leak: start %llu end %llu state %u in tree %d refs %d\n",
state->start, state->end, state->state,
extent_state_in_tree(state),
refcount_read(&state->refs));
list_del(&state->leak_list);
kmem_cache_free(extent_state_cache, state);
}
}
#define btrfs_debug_check_extent_io_range(tree, start, end) \
__btrfs_debug_check_extent_io_range(__func__, (tree), (start), (end))
static inline void __btrfs_debug_check_extent_io_range(const char *caller,
struct extent_io_tree *tree, u64 start, u64 end)
{
struct inode *inode = tree->private_data;
u64 isize;
if (!inode || !is_data_inode(inode))
return;
isize = i_size_read(inode);
if (end >= PAGE_SIZE && (end % 2) == 0 && end != isize - 1) {
btrfs_debug_rl(BTRFS_I(inode)->root->fs_info,
"%s: ino %llu isize %llu odd range [%llu,%llu]",
caller, btrfs_ino(BTRFS_I(inode)), isize, start, end);
}
}
#else
#define btrfs_leak_debug_add(lock, new, head) do {} while (0)
#define btrfs_leak_debug_del(lock, entry) do {} while (0)
#define btrfs_extent_state_leak_debug_check() do {} while (0)
#define btrfs_debug_check_extent_io_range(c, s, e) do {} while (0)
#endif
struct tree_entry {
u64 start;
u64 end;
struct rb_node rb_node;
};
struct extent_page_data {
struct btrfs_bio_ctrl bio_ctrl;
/* tells writepage not to lock the state bits for this range
* it still does the unlocking
*/
unsigned int extent_locked:1;
/* tells the submit_bio code to use REQ_SYNC */
unsigned int sync_io:1;
};
static int add_extent_changeset(struct extent_state *state, u32 bits,
struct extent_changeset *changeset,
int set)
{
int ret;
if (!changeset)
return 0;
if (set && (state->state & bits) == bits)
return 0;
if (!set && (state->state & bits) == 0)
return 0;
changeset->bytes_changed += state->end - state->start + 1;
ret = ulist_add(&changeset->range_changed, state->start, state->end,
GFP_ATOMIC);
return ret;
}
int __must_check submit_one_bio(struct bio *bio, int mirror_num,
unsigned long bio_flags)
{
blk_status_t ret = 0;
struct extent_io_tree *tree = bio->bi_private;
bio->bi_private = NULL;
/* Caller should ensure the bio has at least some range added */
ASSERT(bio->bi_iter.bi_size);
if (is_data_inode(tree->private_data))
ret = btrfs_submit_data_bio(tree->private_data, bio, mirror_num,
bio_flags);
else
ret = btrfs_submit_metadata_bio(tree->private_data, bio,
mirror_num, bio_flags);
return blk_status_to_errno(ret);
}
/* Cleanup unsubmitted bios */
static void end_write_bio(struct extent_page_data *epd, int ret)
{
struct bio *bio = epd->bio_ctrl.bio;
if (bio) {
bio->bi_status = errno_to_blk_status(ret);
bio_endio(bio);
epd->bio_ctrl.bio = NULL;
}
}
/*
* Submit bio from extent page data via submit_one_bio
*
* Return 0 if everything is OK.
* Return <0 for error.
*/
static int __must_check flush_write_bio(struct extent_page_data *epd)
{
int ret = 0;
struct bio *bio = epd->bio_ctrl.bio;
if (bio) {
ret = submit_one_bio(bio, 0, 0);
/*
* Clean up of epd->bio is handled by its endio function.
* And endio is either triggered by successful bio execution
* or the error handler of submit bio hook.
* So at this point, no matter what happened, we don't need
* to clean up epd->bio.
*/
epd->bio_ctrl.bio = NULL;
}
return ret;
}
int __init extent_state_cache_init(void)
{
extent_state_cache = kmem_cache_create("btrfs_extent_state",
sizeof(struct extent_state), 0,
SLAB_MEM_SPREAD, NULL);
if (!extent_state_cache)
return -ENOMEM;
return 0;
}
int __init extent_io_init(void)
{
extent_buffer_cache = kmem_cache_create("btrfs_extent_buffer",
sizeof(struct extent_buffer), 0,
SLAB_MEM_SPREAD, NULL);
if (!extent_buffer_cache)
return -ENOMEM;
if (bioset_init(&btrfs_bioset, BIO_POOL_SIZE,
offsetof(struct btrfs_bio, bio),
BIOSET_NEED_BVECS))
goto free_buffer_cache;
if (bioset_integrity_create(&btrfs_bioset, BIO_POOL_SIZE))
goto free_bioset;
return 0;
free_bioset:
bioset_exit(&btrfs_bioset);
free_buffer_cache:
kmem_cache_destroy(extent_buffer_cache);
extent_buffer_cache = NULL;
return -ENOMEM;
}
void __cold extent_state_cache_exit(void)
{
btrfs_extent_state_leak_debug_check();
kmem_cache_destroy(extent_state_cache);
}
void __cold extent_io_exit(void)
{
/*
* Make sure all delayed rcu free are flushed before we
* destroy caches.
*/
rcu_barrier();
kmem_cache_destroy(extent_buffer_cache);
bioset_exit(&btrfs_bioset);
}
/*
* For the file_extent_tree, we want to hold the inode lock when we lookup and
* update the disk_i_size, but lockdep will complain because our io_tree we hold
* the tree lock and get the inode lock when setting delalloc. These two things
* are unrelated, so make a class for the file_extent_tree so we don't get the
* two locking patterns mixed up.
*/
static struct lock_class_key file_extent_tree_class;
void extent_io_tree_init(struct btrfs_fs_info *fs_info,
struct extent_io_tree *tree, unsigned int owner,
void *private_data)
{
tree->fs_info = fs_info;
tree->state = RB_ROOT;
tree->dirty_bytes = 0;
spin_lock_init(&tree->lock);
tree->private_data = private_data;
tree->owner = owner;
if (owner == IO_TREE_INODE_FILE_EXTENT)
lockdep_set_class(&tree->lock, &file_extent_tree_class);
}
void extent_io_tree_release(struct extent_io_tree *tree)
{
spin_lock(&tree->lock);
/*
* Do a single barrier for the waitqueue_active check here, the state
* of the waitqueue should not change once extent_io_tree_release is
* called.
*/
smp_mb();
while (!RB_EMPTY_ROOT(&tree->state)) {
struct rb_node *node;
struct extent_state *state;
node = rb_first(&tree->state);
state = rb_entry(node, struct extent_state, rb_node);
rb_erase(&state->rb_node, &tree->state);
RB_CLEAR_NODE(&state->rb_node);
/*
* btree io trees aren't supposed to have tasks waiting for
* changes in the flags of extent states ever.
*/
ASSERT(!waitqueue_active(&state->wq));
free_extent_state(state);
cond_resched_lock(&tree->lock);
}
spin_unlock(&tree->lock);
}
static struct extent_state *alloc_extent_state(gfp_t mask)
{
struct extent_state *state;
/*
* The given mask might be not appropriate for the slab allocator,
* drop the unsupported bits
*/
mask &= ~(__GFP_DMA32|__GFP_HIGHMEM);
state = kmem_cache_alloc(extent_state_cache, mask);
if (!state)
return state;
state->state = 0;
state->failrec = NULL;
RB_CLEAR_NODE(&state->rb_node);
btrfs_leak_debug_add(&leak_lock, &state->leak_list, &states);
refcount_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 (refcount_dec_and_test(&state->refs)) {
WARN_ON(extent_state_in_tree(state));
btrfs_leak_debug_del(&leak_lock, &state->leak_list);
trace_free_extent_state(state, _RET_IP_);
kmem_cache_free(extent_state_cache, state);
}
}
static struct rb_node *tree_insert(struct rb_root *root,
struct rb_node *search_start,
u64 offset,
struct rb_node *node,
struct rb_node ***p_in,
struct rb_node **parent_in)
{
struct rb_node **p;
struct rb_node *parent = NULL;
struct tree_entry *entry;
if (p_in && parent_in) {
p = *p_in;
parent = *parent_in;
goto do_insert;
}
p = search_start ? &search_start : &root->rb_node;
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;
}
do_insert:
rb_link_node(node, parent, p);
rb_insert_color(node, root);
return NULL;
}
/**
* Search @tree for an entry that contains @offset. Such entry would have
* entry->start <= offset && entry->end >= offset.
*
* @tree: the tree to search
* @offset: offset that should fall within an entry in @tree
* @next_ret: pointer to the first entry whose range ends after @offset
* @prev_ret: pointer to the first entry whose range begins before @offset
* @p_ret: pointer where new node should be anchored (used when inserting an
* entry in the tree)
* @parent_ret: points to entry which would have been the parent of the entry,
* containing @offset
*
* This function returns a pointer to the entry that contains @offset byte
* address. If no such entry exists, then NULL is returned and the other
* pointer arguments to the function are filled, otherwise the found entry is
* returned and other pointers are left untouched.
*/
static struct rb_node *__etree_search(struct extent_io_tree *tree, u64 offset,
struct rb_node **next_ret,
struct rb_node **prev_ret,
struct rb_node ***p_ret,
struct rb_node **parent_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) {
prev = *n;
entry = rb_entry(prev, struct tree_entry, rb_node);
prev_entry = entry;
if (offset < entry->start)
n = &(*n)->rb_left;
else if (offset > entry->end)
n = &(*n)->rb_right;
else
return *n;
}
if (p_ret)
*p_ret = n;
if (parent_ret)
*parent_ret = prev;
if (next_ret) {
orig_prev = prev;
while (prev && offset > prev_entry->end) {
prev = rb_next(prev);
prev_entry = rb_entry(prev, struct tree_entry, rb_node);
}
*next_ret = prev;
prev = orig_prev;
}
if (prev_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);
}
*prev_ret = prev;
}
return NULL;
}
static inline struct rb_node *
tree_search_for_insert(struct extent_io_tree *tree,
u64 offset,
struct rb_node ***p_ret,
struct rb_node **parent_ret)
{
struct rb_node *next= NULL;
struct rb_node *ret;
ret = __etree_search(tree, offset, &next, NULL, p_ret, parent_ret);
if (!ret)
return next;
return ret;
}
static inline struct rb_node *tree_search(struct extent_io_tree *tree,
u64 offset)
{
return tree_search_for_insert(tree, offset, NULL, NULL);
}
/*
* utility function to look for merge candidates inside a given range.
* Any extents with matching state are merged together into a single
* extent in the tree. Extents with EXTENT_IO in their state field
* are not merged because the end_io handlers need to be able to do
* operations on them without sleeping (or doing allocations/splits).
*
* This should be called with the tree lock held.
*/
static 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_LOCKED | 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) {
if (tree->private_data &&
is_data_inode(tree->private_data))
btrfs_merge_delalloc_extent(tree->private_data,
state, other);
state->start = other->start;
rb_erase(&other->rb_node, &tree->state);
RB_CLEAR_NODE(&other->rb_node);
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) {
if (tree->private_data &&
is_data_inode(tree->private_data))
btrfs_merge_delalloc_extent(tree->private_data,
state, other);
state->end = other->end;
rb_erase(&other->rb_node, &tree->state);
RB_CLEAR_NODE(&other->rb_node);
free_extent_state(other);
}
}
}
static void set_state_bits(struct extent_io_tree *tree,
struct extent_state *state, u32 *bits,
struct extent_changeset *changeset);
/*
* insert an extent_state struct into the tree. 'bits' are set on the
* struct before it is inserted.
*
* This may return -EEXIST if the extent is already there, in which case the
* state struct is freed.
*
* The tree lock is not taken internally. This is a utility function and
* probably isn't what you want to call (see set/clear_extent_bit).
*/
static int insert_state(struct extent_io_tree *tree,
struct extent_state *state, u64 start, u64 end,
struct rb_node ***p,
struct rb_node **parent,
u32 *bits, struct extent_changeset *changeset)
{
struct rb_node *node;
if (end < start) {
btrfs_err(tree->fs_info,
"insert state: end < start %llu %llu", end, start);
WARN_ON(1);
}
state->start = start;
state->end = end;
set_state_bits(tree, state, bits, changeset);
node = tree_insert(&tree->state, NULL, end, &state->rb_node, p, parent);
if (node) {
struct extent_state *found;
found = rb_entry(node, struct extent_state, rb_node);
btrfs_err(tree->fs_info,
"found node %llu %llu on insert of %llu %llu",
found->start, found->end, start, end);
return -EEXIST;
}
merge_state(tree, state);
return 0;
}
/*
* split a given extent state struct in two, inserting the preallocated
* struct 'prealloc' as the newly created second half. 'split' indicates an
* offset inside 'orig' where it should be split.
*
* Before calling,
* the tree has 'orig' at [orig->start, orig->end]. After calling, there
* are two extent state structs in the tree:
* prealloc: [orig->start, split - 1]
* orig: [ split, orig->end ]
*
* The tree locks are not taken by this function. They need to be held
* by the caller.
*/
static int split_state(struct extent_io_tree *tree, struct extent_state *orig,
struct extent_state *prealloc, u64 split)
{
struct rb_node *node;
if (tree->private_data && is_data_inode(tree->private_data))
btrfs_split_delalloc_extent(tree->private_data, orig, split);
prealloc->start = orig->start;
prealloc->end = split - 1;
prealloc->state = orig->state;
orig->start = split;
node = tree_insert(&tree->state, &orig->rb_node, prealloc->end,
&prealloc->rb_node, NULL, NULL);
if (node) {
free_extent_state(prealloc);
return -EEXIST;
}
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;
}
/*
* utility function to clear some bits in an extent state struct.
* it will optionally wake up anyone waiting on this state (wake == 1).
*
* If no bits are set on the state struct after clearing things, the
* struct is freed and removed from the tree
*/
static struct extent_state *clear_state_bit(struct extent_io_tree *tree,
struct extent_state *state,
u32 *bits, int wake,
struct extent_changeset *changeset)
{
struct extent_state *next;
u32 bits_to_clear = *bits & ~EXTENT_CTLBITS;
int ret;
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;
}
if (tree->private_data && is_data_inode(tree->private_data))
btrfs_clear_delalloc_extent(tree->private_data, state, bits);
ret = add_extent_changeset(state, bits_to_clear, changeset, 0);
BUG_ON(ret < 0);
state->state &= ~bits_to_clear;
if (wake)
wake_up(&state->wq);
if (state->state == 0) {
next = next_state(state);
if (extent_state_in_tree(state)) {
rb_erase(&state->rb_node, &tree->state);
RB_CLEAR_NODE(&state->rb_node);
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;
}
static void extent_io_tree_panic(struct extent_io_tree *tree, int err)
{
btrfs_panic(tree->fs_info, err,
"locking error: extent tree was modified by another thread while locked");
}
/*
* clear some bits on a range in the tree. This may require splitting
* or inserting elements in the tree, so the gfp mask is used to
* indicate which allocations or sleeping are allowed.
*
* pass 'wake' == 1 to kick any sleepers, and 'delete' == 1 to remove
* the given range from the tree regardless of state (ie for truncate).
*
* the range [start, end] is inclusive.
*
* This takes the tree lock, and returns 0 on success and < 0 on error.
*/
int __clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
u32 bits, int wake, int delete,
struct extent_state **cached_state,
gfp_t mask, struct extent_changeset *changeset)
{
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;
btrfs_debug_check_extent_io_range(tree, start, end);
trace_btrfs_clear_extent_bit(tree, start, end - start + 1, bits);
if (bits & EXTENT_DELALLOC)
bits |= EXTENT_NORESERVE;
if (delete)
bits |= ~EXTENT_CTLBITS;
if (bits & (EXTENT_LOCKED | EXTENT_BOUNDARY))
clear = 1;
again:
if (!prealloc && gfpflags_allow_blocking(mask)) {
/*
* Don't care for allocation failure here because we might end
* up not needing the pre-allocated extent state at all, which
* is the case if we only have in the tree extent states that
* cover our input range and don't cover too any other range.
* If we end up needing a new extent state we allocate it later.
*/
prealloc = alloc_extent_state(mask);
}
spin_lock(&tree->lock);
if (cached_state) {
cached = *cached_state;
if (clear) {
*cached_state = NULL;
cached_state = NULL;
}
if (cached && extent_state_in_tree(cached) &&
cached->start <= start && cached->end > start) {
if (clear)
refcount_dec(&cached->refs);
state = cached;
goto hit_next;
}
if (clear)
free_extent_state(cached);
}
/*
* this search will find the extents that end after
* our range starts
*/
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;
/* the state doesn't have the wanted bits, go ahead */
if (!(state->state & bits)) {
state = next_state(state);
goto next;
}
/*
* | ---- desired range ---- |
* | state | or
* | ------------- state -------------- |
*
* We need to split the extent we found, and may flip
* bits on second half.
*
* If the extent we found extends past our range, we
* just split and search again. It'll get split again
* the next time though.
*
* If the extent we found is inside our range, we clear
* the desired bit on it.
*/
if (state->start < start) {
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) {
state = clear_state_bit(tree, state, &bits, wake,
changeset);
goto next;
}
goto search_again;
}
/*
* | ---- desired range ---- |
* | state |
* We need to split the extent, and clear the bit
* on the first half
*/
if (state->start <= end && state->end > end) {
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, changeset);
prealloc = NULL;
goto out;
}
state = clear_state_bit(tree, state, &bits, wake, changeset);
next:
if (last_end == (u64)-1)
goto out;
start = last_end + 1;
if (start <= end && state && !need_resched())
goto hit_next;
search_again:
if (start > end)
goto out;
spin_unlock(&tree->lock);
if (gfpflags_allow_blocking(mask))
cond_resched();
goto again;
out:
spin_unlock(&tree->lock);
if (prealloc)
free_extent_state(prealloc);
return 0;
}
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);
}
/*
* waits for one or more bits to clear on a range in the state tree.
* The range [start, end] is inclusive.
* The tree lock is taken by this function
*/
static void wait_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
u32 bits)
{
struct extent_state *state;
struct rb_node *node;
btrfs_debug_check_extent_io_range(tree, start, end);
spin_lock(&tree->lock);
again:
while (1) {
/*
* this search will find all the extents that end after
* our range starts
*/
node = tree_search(tree, start);
process_node:
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;
refcount_inc(&state->refs);
wait_on_state(tree, state);
free_extent_state(state);
goto again;
}
start = state->end + 1;
if (start > end)
break;
if (!cond_resched_lock(&tree->lock)) {
node = rb_next(node);
goto process_node;
}
}
out:
spin_unlock(&tree->lock);
}
static void set_state_bits(struct extent_io_tree *tree,
struct extent_state *state,
u32 *bits, struct extent_changeset *changeset)
{
u32 bits_to_set = *bits & ~EXTENT_CTLBITS;
int ret;
if (tree->private_data && is_data_inode(tree->private_data))
btrfs_set_delalloc_extent(tree->private_data, state, bits);
if ((bits_to_set & EXTENT_DIRTY) && !(state->state & EXTENT_DIRTY)) {
u64 range = state->end - state->start + 1;
tree->dirty_bytes += range;
}
ret = add_extent_changeset(state, bits_to_set, changeset, 1);
BUG_ON(ret < 0);
state->state |= bits_to_set;
}
static void cache_state_if_flags(struct extent_state *state,
struct extent_state **cached_ptr,
unsigned flags)
{
if (cached_ptr && !(*cached_ptr)) {
if (!flags || (state->state & flags)) {
*cached_ptr = state;
refcount_inc(&state->refs);
}
}
}
static void cache_state(struct extent_state *state,
struct extent_state **cached_ptr)
{
return cache_state_if_flags(state, cached_ptr,
EXTENT_LOCKED | EXTENT_BOUNDARY);
}
/*
* set some bits on a range in the tree. This may require allocations or
* sleeping, so the gfp mask is used to indicate what is allowed.
*
* If any of the exclusive bits are set, this will fail with -EEXIST if some
* part of the range already has the desired bits set. The start of the
* existing range is returned in failed_start in this case.
*
* [start, end] is inclusive This takes the tree lock.
*/
int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end, u32 bits,
u32 exclusive_bits, u64 *failed_start,
struct extent_state **cached_state, gfp_t mask,
struct extent_changeset *changeset)
{
struct extent_state *state;
struct extent_state *prealloc = NULL;
struct rb_node *node;
struct rb_node **p;
struct rb_node *parent;
int err = 0;
u64 last_start;
u64 last_end;
btrfs_debug_check_extent_io_range(tree, start, end);
trace_btrfs_set_extent_bit(tree, start, end - start + 1, bits);
if (exclusive_bits)
ASSERT(failed_start);
else
ASSERT(failed_start == NULL);
again:
if (!prealloc && gfpflags_allow_blocking(mask)) {
/*
* Don't care for allocation failure here because we might end
* up not needing the pre-allocated extent state at all, which
* is the case if we only have in the tree extent states that
* cover our input range and don't cover too any other range.
* If we end up needing a new extent state we allocate it later.
*/
prealloc = alloc_extent_state(mask);
}
spin_lock(&tree->lock);
if (cached_state && *cached_state) {
state = *cached_state;
if (state->start <= start && state->end > start &&
extent_state_in_tree(state)) {
node = &state->rb_node;
goto hit_next;
}
}
/*
* this search will find all the extents that end after
* our range starts.
*/
node = tree_search_for_insert(tree, start, &p, &parent);
if (!node) {
prealloc = alloc_extent_state_atomic(prealloc);
BUG_ON(!prealloc);
err = insert_state(tree, prealloc, start, end,
&p, &parent, &bits, changeset);
if (err)
extent_io_tree_panic(tree, err);
cache_state(prealloc, cached_state);
prealloc = NULL;
goto out;
}
state = rb_entry(node, struct extent_state, rb_node);
hit_next:
last_start = state->start;
last_end = state->end;
/*
* | ---- desired range ---- |
* | state |
*
* Just lock what we found and keep going
*/
if (state->start == start && state->end <= end) {
if (state->state & exclusive_bits) {
*failed_start = state->start;
err = -EEXIST;
goto out;
}
set_state_bits(tree, state, &bits, changeset);
cache_state(state, cached_state);
merge_state(tree, state);
if (last_end == (u64)-1)
goto out;
start = last_end + 1;
state = next_state(state);
if (start < end && state && state->start == start &&
!need_resched())
goto hit_next;
goto search_again;
}
/*
* | ---- desired range ---- |
* | state |
* or
* | ------------- state -------------- |
*
* We need to split the extent we found, and may flip bits on
* second half.
*
* If the extent we found extends past our
* range, we just split and search again. It'll get split
* again the next time though.
*
* If the extent we found is inside our range, we set the
* desired bit on it.
*/
if (state->start < start) {
if (state->state & exclusive_bits) {
*failed_start = start;
err = -EEXIST;
goto out;
}
/*
* If this extent already has all the bits we want set, then
* skip it, not necessary to split it or do anything with it.
*/
if ((state->state & bits) == bits) {
start = state->end + 1;
cache_state(state, cached_state);
goto search_again;
}
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, changeset);
cache_state(state, cached_state);
merge_state(tree, state);
if (last_end == (u64)-1)
goto out;
start = last_end + 1;
state = next_state(state);
if (start < end && state && state->start == start &&
!need_resched())
goto hit_next;
}
goto search_again;
}
/*
* | ---- desired range ---- |
* | state | or | state |
*
* There's a hole, we need to insert something in it and
* ignore the extent we found.
*/
if (state->start > start) {
u64 this_end;
if (end < last_start)
this_end = end;
else
this_end = last_start - 1;
prealloc = alloc_extent_state_atomic(prealloc);
BUG_ON(!prealloc);
/*
* Avoid to free 'prealloc' if it can be merged with
* the later extent.
*/
err = insert_state(tree, prealloc, start, this_end,
NULL, NULL, &bits, changeset);
if (err)
extent_io_tree_panic(tree, err);
cache_state(prealloc, cached_state);
prealloc = NULL;
start = this_end + 1;
goto search_again;
}
/*
* | ---- desired range ---- |
* | state |
* We need to split the extent, and set the bit
* on the first half
*/
if (state->start <= end && state->end > end) {
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, changeset);
cache_state(prealloc, cached_state);
merge_state(tree, prealloc);
prealloc = NULL;
goto out;
}
search_again:
if (start > end)
goto out;
spin_unlock(&tree->lock);
if (gfpflags_allow_blocking(mask))
cond_resched();
goto again;
out:
spin_unlock(&tree->lock);
if (prealloc)
free_extent_state(prealloc);
return err;
}
/**
* convert_extent_bit - convert all bits in a given range from one bit to
* another
* @tree: the io tree to search
* @start: the start offset in bytes
* @end: the end offset in bytes (inclusive)
* @bits: the bits to set in this range
* @clear_bits: the bits to clear in this range
* @cached_state: state that we're going to cache
*
* This will go through and set bits for the given range. If any states exist
* already in this range they are set with the given bit and cleared of the
* clear_bits. This is only meant to be used by things that are mergeable, ie
* converting from say DELALLOC to DIRTY. This is not meant to be used with
* boundary bits like LOCK.
*
* All allocations are done with GFP_NOFS.
*/
int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
u32 bits, u32 clear_bits,
struct extent_state **cached_state)
{
struct extent_state *state;
struct extent_state *prealloc = NULL;
struct rb_node *node;
struct rb_node **p;
struct rb_node *parent;
int err = 0;
u64 last_start;
u64 last_end;
bool first_iteration = true;
btrfs_debug_check_extent_io_range(tree, start, end);
trace_btrfs_convert_extent_bit(tree, start, end - start + 1, bits,
clear_bits);
again:
if (!prealloc) {
/*
* Best effort, don't worry if extent state allocation fails
* here for the first iteration. We might have a cached state
* that matches exactly the target range, in which case no
* extent state allocations are needed. We'll only know this
* after locking the tree.
*/
prealloc = alloc_extent_state(GFP_NOFS);
if (!prealloc && !first_iteration)
return -ENOMEM;
}
spin_lock(&tree->lock);
if (cached_state && *cached_state) {
state = *cached_state;
if (state->start <= start && state->end > start &&
extent_state_in_tree(state)) {
node = &state->rb_node;
goto hit_next;
}
}
/*
* this search will find all the extents that end after
* our range starts.
*/
node = tree_search_for_insert(tree, start, &p, &parent);
if (!node) {
prealloc = alloc_extent_state_atomic(prealloc);
if (!prealloc) {
err = -ENOMEM;
goto out;
}
err = insert_state(tree, prealloc, start, end,
&p, &parent, &bits, NULL);
if (err)
extent_io_tree_panic(tree, err);
cache_state(prealloc, cached_state);
prealloc = NULL;
goto out;
}
state = rb_entry(node, struct extent_state, rb_node);
hit_next:
last_start = state->start;
last_end = state->end;
/*
* | ---- desired range ---- |
* | state |
*
* Just lock what we found and keep going
*/
if (state->start == start && state->end <= end) {
set_state_bits(tree, state, &bits, NULL);
cache_state(state, cached_state);
state = clear_state_bit(tree, state, &clear_bits, 0, NULL);
if (last_end == (u64)-1)
goto out;
start = last_end + 1;
if (start < end && state && state->start == start &&
!need_resched())
goto hit_next;
goto search_again;
}
/*
* | ---- desired range ---- |
* | state |
* or
* | ------------- state -------------- |
*
* We need to split the extent we found, and may flip bits on
* second half.
*
* If the extent we found extends past our
* range, we just split and search again. It'll get split
* again the next time though.
*
* If the extent we found is inside our range, we set the
* desired bit on it.
*/
if (state->start < start) {
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, NULL);
cache_state(state, cached_state);
state = clear_state_bit(tree, state, &clear_bits, 0,
NULL);
if (last_end == (u64)-1)
goto out;
start = last_end + 1;
if (start < end && state && state->start == start &&
!need_resched())
goto hit_next;
}
goto search_again;
}
/*
* | ---- desired range ---- |
* | state | or | state |
*
* There's a hole, we need to insert something in it and
* ignore the extent we found.
*/
if (state->start > start) {
u64 this_end;
if (end < last_start)
this_end = end;
else
this_end = last_start - 1;
prealloc = alloc_extent_state_atomic(prealloc);
if (!prealloc) {
err = -ENOMEM;
goto out;
}
/*
* Avoid to free 'prealloc' if it can be merged with
* the later extent.
*/
err = insert_state(tree, prealloc, start, this_end,
NULL, NULL, &bits, NULL);
if (err)
extent_io_tree_panic(tree, err);
cache_state(prealloc, cached_state);
prealloc = NULL;
start = this_end + 1;
goto search_again;
}
/*
* | ---- desired range ---- |
* | state |
* We need to split the extent, and set the bit
* on the first half
*/
if (state->start <= end && state->end > end) {
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, NULL);
cache_state(prealloc, cached_state);
clear_state_bit(tree, prealloc, &clear_bits, 0, NULL);
prealloc = NULL;
goto out;
}
search_again:
if (start > end)
goto out;
spin_unlock(&tree->lock);
cond_resched();
first_iteration = false;
goto again;
out:
spin_unlock(&tree->lock);
if (prealloc)
free_extent_state(prealloc);
return err;
}
/* wrappers around set/clear extent bit */
int set_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
u32 bits, struct extent_changeset *changeset)
{
/*
* We don't support EXTENT_LOCKED yet, as current changeset will
* record any bits changed, so for EXTENT_LOCKED case, it will
* either fail with -EEXIST or changeset will record the whole
* range.
*/
BUG_ON(bits & EXTENT_LOCKED);
return set_extent_bit(tree, start, end, bits, 0, NULL, NULL, GFP_NOFS,
changeset);
}
int set_extent_bits_nowait(struct extent_io_tree *tree, u64 start, u64 end,
u32 bits)
{
return set_extent_bit(tree, start, end, bits, 0, NULL, NULL,
GFP_NOWAIT, NULL);
}
int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
u32 bits, int wake, int delete,
struct extent_state **cached)
{
return __clear_extent_bit(tree, start, end, bits, wake, delete,
cached, GFP_NOFS, NULL);
}
int clear_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
u32 bits, struct extent_changeset *changeset)
{
/*
* Don't support EXTENT_LOCKED case, same reason as
* set_record_extent_bits().
*/
BUG_ON(bits & EXTENT_LOCKED);
return __clear_extent_bit(tree, start, end, bits, 0, 0, NULL, GFP_NOFS,
changeset);
}
/*
* either insert or lock state struct between start and end use mask to tell
* us if waiting is desired.
*/
int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
struct extent_state **cached_state)
{
int err;
u64 failed_start;
while (1) {
err = set_extent_bit(tree, start, end, EXTENT_LOCKED,
EXTENT_LOCKED, &failed_start,
cached_state, GFP_NOFS, NULL);
if (err == -EEXIST) {
wait_extent_bit(tree, failed_start, end, EXTENT_LOCKED);
start = failed_start;
} else
break;
WARN_ON(start > end);
}
return err;
}
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, NULL);
if (err == -EEXIST) {
if (failed_start > start)
clear_extent_bit(tree, start, failed_start - 1,
EXTENT_LOCKED, 1, 0, NULL);
return 0;
}
return 1;
}
void extent_range_clear_dirty_for_io(struct inode *inode, u64 start, u64 end)
{
unsigned long index = start >> PAGE_SHIFT;
unsigned long end_index = end >> PAGE_SHIFT;
struct page *page;
while (index <= end_index) {
page = find_get_page(inode->i_mapping, index);
BUG_ON(!page); /* Pages should be in the extent_io_tree */
clear_page_dirty_for_io(page);
put_page(page);
index++;
}
}
void extent_range_redirty_for_io(struct inode *inode, u64 start, u64 end)
{
unsigned long index = start >> PAGE_SHIFT;
unsigned long end_index = end >> PAGE_SHIFT;
struct page *page;
while (index <= end_index) {
page = find_get_page(inode->i_mapping, index);
BUG_ON(!page); /* Pages should be in the extent_io_tree */
__set_page_dirty_nobuffers(page);
account_page_redirty(page);
put_page(page);
index++;
}
}
/* find the first state struct with 'bits' set after 'start', and
* return it. tree->lock must be held. NULL will returned if
* nothing was found after 'start'
*/
static struct extent_state *
find_first_extent_bit_state(struct extent_io_tree *tree, u64 start, u32 bits)
{
struct rb_node *node;
struct extent_state *state;
/*
* this search will find all the extents that end after
* our range starts.
*/
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;
}
/*
* Find the first offset in the io tree with one or more @bits set.
*
* Note: If there are multiple bits set in @bits, any of them will match.
*
* Return 0 if we find something, and update @start_ret and @end_ret.
* Return 1 if we found nothing.
*/
int find_first_extent_bit(struct extent_io_tree *tree, u64 start,
u64 *start_ret, u64 *end_ret, u32 bits,
struct extent_state **cached_state)
{
struct extent_state *state;
int ret = 1;
spin_lock(&tree->lock);
if (cached_state && *cached_state) {
state = *cached_state;
if (state->end == start - 1 && extent_state_in_tree(state)) {
while ((state = next_state(state)) != NULL) {
if (state->state & bits)
goto got_it;
}
free_extent_state(*cached_state);
*cached_state = NULL;
goto out;
}
free_extent_state(*cached_state);
*cached_state = NULL;
}
state = find_first_extent_bit_state(tree, start, bits);
got_it:
if (state) {
cache_state_if_flags(state, cached_state, 0);
*start_ret = state->start;
*end_ret = state->end;
ret = 0;
}
out:
spin_unlock(&tree->lock);
return ret;
}
/**
* Find a contiguous area of bits
*
* @tree: io tree to check
* @start: offset to start the search from
* @start_ret: the first offset we found with the bits set
* @end_ret: the final contiguous range of the bits that were set
* @bits: bits to look for
*
* set_extent_bit and clear_extent_bit can temporarily split contiguous ranges
* to set bits appropriately, and then merge them again. During this time it
* will drop the tree->lock, so use this helper if you want to find the actual
* contiguous area for given bits. We will search to the first bit we find, and
* then walk down the tree until we find a non-contiguous area. The area
* returned will be the full contiguous area with the bits set.
*/
int find_contiguous_extent_bit(struct extent_io_tree *tree, u64 start,
u64 *start_ret, u64 *end_ret, u32 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;
while ((state = next_state(state)) != NULL) {
if (state->start > (*end_ret + 1))
break;
*end_ret = state->end;
}
ret = 0;
}
spin_unlock(&tree->lock);
return ret;
}
/**
* Find the first range that has @bits not set. This range could start before
* @start.
*
* @tree: the tree to search
* @start: offset at/after which the found extent should start
* @start_ret: records the beginning of the range
* @end_ret: records the end of the range (inclusive)
* @bits: the set of bits which must be unset
*
* Since unallocated range is also considered one which doesn't have the bits
* set it's possible that @end_ret contains -1, this happens in case the range
* spans (last_range_end, end of device]. In this case it's up to the caller to
* trim @end_ret to the appropriate size.
*/
void find_first_clear_extent_bit(struct extent_io_tree *tree, u64 start,
u64 *start_ret, u64 *end_ret, u32 bits)
{
struct extent_state *state;
struct rb_node *node, *prev = NULL, *next;
spin_lock(&tree->lock);
/* Find first extent with bits cleared */
while (1) {
node = __etree_search(tree, start, &next, &prev, NULL, NULL);
if (!node && !next && !prev) {
/*
* Tree is completely empty, send full range and let
* caller deal with it
*/
*start_ret = 0;
*end_ret = -1;
goto out;
} else if (!node && !next) {
/*
* We are past the last allocated chunk, set start at
* the end of the last extent.
*/
state = rb_entry(prev, struct extent_state, rb_node);
*start_ret = state->end + 1;
*end_ret = -1;
goto out;
} else if (!node) {
node = next;
}
/*
* At this point 'node' either contains 'start' or start is
* before 'node'
*/
state = rb_entry(node, struct extent_state, rb_node);
if (in_range(start, state->start, state->end - state->start + 1)) {
if (state->state & bits) {
/*
* |--range with bits sets--|
* |
* start
*/
start = state->end + 1;
} else {
/*
* 'start' falls within a range that doesn't
* have the bits set, so take its start as
* the beginning of the desired range
*
* |--range with bits cleared----|
* |
* start
*/
*start_ret = state->start;
break;
}
} else {
/*
* |---prev range---|---hole/unset---|---node range---|
* |
* start
*
* or
*
* |---hole/unset--||--first node--|
* 0 |
* start
*/
if (prev) {
state = rb_entry(prev, struct extent_state,
rb_node);
*start_ret = state->end + 1;
} else {
*start_ret = 0;
}
break;
}
}
/*
* Find the longest stretch from start until an entry which has the
* bits set
*/
while (1) {
state = rb_entry(node, struct extent_state, rb_node);
if (state->end >= start && !(state->state & bits)) {
*end_ret = state->end;
} else {
*end_ret = state->start - 1;
break;
}
node = rb_next(node);
if (!node)
break;
}
out:
spin_unlock(&tree->lock);
}
/*
* find a contiguous range of bytes in the file marked as delalloc, not
* more than 'max_bytes'. start and end are used to return the range,
*
* true is returned if we find something, false if nothing was in the tree
*/
bool btrfs_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;
bool found = false;
u64 total_bytes = 0;
spin_lock(&tree->lock);
/*
* this search will find all the extents that end after
* our range starts.
*/
node = tree_search(tree, cur_start);
if (!node) {
*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;
refcount_inc(&state->refs);
}
found = true;
*end = state->end;
cur_start = state->end + 1;
node = rb_next(node);
total_bytes += state->end - state->start + 1;
if (total_bytes >= max_bytes)
break;
if (!node)
break;
}
out:
spin_unlock(&tree->lock);
return found;
}
/*
* Process one page for __process_pages_contig().
*
* Return >0 if we hit @page == @locked_page.
* Return 0 if we updated the page status.
* Return -EGAIN if the we need to try again.
* (For PAGE_LOCK case but got dirty page or page not belong to mapping)
*/
static int process_one_page(struct btrfs_fs_info *fs_info,
struct address_space *mapping,
struct page *page, struct page *locked_page,
unsigned long page_ops, u64 start, u64 end)
{
u32 len;
ASSERT(end + 1 - start != 0 && end + 1 - start < U32_MAX);
len = end + 1 - start;
if (page_ops & PAGE_SET_ORDERED)
btrfs_page_clamp_set_ordered(fs_info, page, start, len);
if (page_ops & PAGE_SET_ERROR)
btrfs_page_clamp_set_error(fs_info, page, start, len);
if (page_ops & PAGE_START_WRITEBACK) {
btrfs_page_clamp_clear_dirty(fs_info, page, start, len);
btrfs_page_clamp_set_writeback(fs_info, page, start, len);
}
if (page_ops & PAGE_END_WRITEBACK)
btrfs_page_clamp_clear_writeback(fs_info, page, start, len);
if (page == locked_page)
return 1;
if (page_ops & PAGE_LOCK) {
int ret;
ret = btrfs_page_start_writer_lock(fs_info, page, start, len);
if (ret)
return ret;
if (!PageDirty(page) || page->mapping != mapping) {
btrfs_page_end_writer_lock(fs_info, page, start, len);
return -EAGAIN;
}
}
if (page_ops & PAGE_UNLOCK)
btrfs_page_end_writer_lock(fs_info, page, start, len);
return 0;
}
static int __process_pages_contig(struct address_space *mapping,
struct page *locked_page,
u64 start, u64 end, unsigned long page_ops,
u64 *processed_end)
{
struct btrfs_fs_info *fs_info = btrfs_sb(mapping->host->i_sb);
pgoff_t start_index = start >> PAGE_SHIFT;
pgoff_t end_index = end >> PAGE_SHIFT;
pgoff_t index = start_index;
unsigned long nr_pages = end_index - start_index + 1;
unsigned long pages_processed = 0;
struct page *pages[16];
int err = 0;
int i;
if (page_ops & PAGE_LOCK) {
ASSERT(page_ops == PAGE_LOCK);
ASSERT(processed_end && *processed_end == start);
}
if ((page_ops & PAGE_SET_ERROR) && nr_pages > 0)
mapping_set_error(mapping, -EIO);
while (nr_pages > 0) {
int found_pages;
found_pages = find_get_pages_contig(mapping, index,
min_t(unsigned long,
nr_pages, ARRAY_SIZE(pages)), pages);
if (found_pages == 0) {
/*
* Only if we're going to lock these pages, we can find
* nothing at @index.
*/
ASSERT(page_ops & PAGE_LOCK);
err = -EAGAIN;
goto out;
}
for (i = 0; i < found_pages; i++) {
int process_ret;
process_ret = process_one_page(fs_info, mapping,
pages[i], locked_page, page_ops,
start, end);
if (process_ret < 0) {
for (; i < found_pages; i++)
put_page(pages[i]);
err = -EAGAIN;
goto out;
}
put_page(pages[i]);
pages_processed++;
}
nr_pages -= found_pages;
index += found_pages;
cond_resched();
}
out:
if (err && processed_end) {
/*
* Update @processed_end. I know this is awful since it has
* two different return value patterns (inclusive vs exclusive).
*
* But the exclusive pattern is necessary if @start is 0, or we
* underflow and check against processed_end won't work as
* expected.
*/
if (pages_processed)
*processed_end = min(end,
((u64)(start_index + pages_processed) << PAGE_SHIFT) - 1);
else
*processed_end = start;
}
return err;
}
static noinline void __unlock_for_delalloc(struct inode *inode,
struct page *locked_page,
u64 start, u64 end)
{
unsigned long index = start >> PAGE_SHIFT;
unsigned long end_index = end >> PAGE_SHIFT;
ASSERT(locked_page);
if (index == locked_page->index && end_index == index)
return;
__process_pages_contig(inode->i_mapping, locked_page, start, end,
PAGE_UNLOCK, NULL);
}
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_SHIFT;
unsigned long end_index = delalloc_end >> PAGE_SHIFT;
u64 processed_end = delalloc_start;
int ret;
ASSERT(locked_page);
if (index == locked_page->index && index == end_index)
return 0;
ret = __process_pages_contig(inode->i_mapping, locked_page, delalloc_start,
delalloc_end, PAGE_LOCK, &processed_end);
if (ret == -EAGAIN && processed_end > delalloc_start)
__unlock_for_delalloc(inode, locked_page, delalloc_start,
processed_end);
return ret;
}
/*
* Find and lock a contiguous range of bytes in the file marked as delalloc, no
* more than @max_bytes.
*
* @start: The original start bytenr to search.
* Will store the extent range start bytenr.
* @end: The original end bytenr of the search range
* Will store the extent range end bytenr.
*
* Return true if we find a delalloc range which starts inside the original
* range, and @start/@end will store the delalloc range start/end.
*
* Return false if we can't find any delalloc range which starts inside the
* original range, and @start/@end will be the non-delalloc range start/end.
*/
EXPORT_FOR_TESTS
noinline_for_stack bool find_lock_delalloc_range(struct inode *inode,
struct page *locked_page, u64 *start,
u64 *end)
{
struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
const u64 orig_start = *start;
const u64 orig_end = *end;
u64 max_bytes = BTRFS_MAX_EXTENT_SIZE;
u64 delalloc_start;
u64 delalloc_end;
bool found;
struct extent_state *cached_state = NULL;
int ret;
int loops = 0;
/* Caller should pass a valid @end to indicate the search range end */
ASSERT(orig_end > orig_start);
/* The range should at least cover part of the page */
ASSERT(!(orig_start >= page_offset(locked_page) + PAGE_SIZE ||
orig_end <= page_offset(locked_page)));
again:
/* step one, find a bunch of delalloc bytes starting at start */
delalloc_start = *start;
delalloc_end = 0;
found = btrfs_find_delalloc_range(tree, &delalloc_start, &delalloc_end,
max_bytes, &cached_state);
if (!found || delalloc_end <= *start || delalloc_start > orig_end) {
*start = delalloc_start;
/* @delalloc_end can be -1, never go beyond @orig_end */
*end = min(delalloc_end, orig_end);
free_extent_state(cached_state);
return false;
}
/*
* start comes from the offset of locked_page. We have to lock
* pages in order, so we can't process delalloc bytes before
* locked_page
*/
if (delalloc_start < *start)
delalloc_start = *start;
/*
* make sure to limit the number of pages we try to lock down
*/
if (delalloc_end + 1 - delalloc_start > max_bytes)
delalloc_end = delalloc_start + max_bytes - 1;
/* step two, lock all the pages after the page that has start */
ret = lock_delalloc_pages(inode, locked_page,
delalloc_start, delalloc_end);
ASSERT(!ret || ret == -EAGAIN);
if (ret == -EAGAIN) {
/* some of the pages are gone, lets avoid looping by
* shortening the size of the delalloc range we're searching
*/
free_extent_state(cached_state);
cached_state = NULL;
if (!loops) {
max_bytes = PAGE_SIZE;
loops = 1;
goto again;
} else {
found = false;
goto out_failed;
}
}
/* step three, lock the state bits for the whole range */
lock_extent_bits(tree, delalloc_start, delalloc_end, &cached_state);
/* then test to make sure it is all still delalloc */
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);
__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;
}
void extent_clear_unlock_delalloc(struct btrfs_inode *inode, u64 start, u64 end,
struct page *locked_page,
u32 clear_bits, unsigned long page_ops)
{
clear_extent_bit(&inode->io_tree, start, end, clear_bits, 1, 0, NULL);
__process_pages_contig(inode->vfs_inode.i_mapping, locked_page,
start, end, page_ops, NULL);
}
/*
* count the number of bytes in the tree that have a given bit(s)
* set. This can be fairly slow, except for EXTENT_DIRTY which is
* cached. The total number found is returned.
*/
u64 count_range_bits(struct extent_io_tree *tree,
u64 *start, u64 search_end, u64 max_bytes,
u32 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 (WARN_ON(search_end <= cur_start))
return 0;
spin_lock(&tree->lock);
if (cur_start == 0 && bits == EXTENT_DIRTY) {
total_bytes = tree->dirty_bytes;
goto out;
}
/*
* this search will find all the extents that end after
* our range starts.
*/
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;
}
/*
* set the private field for a given byte offset in the tree. If there isn't
* an extent_state there already, this does nothing.
*/
int set_state_failrec(struct extent_io_tree *tree, u64 start,
struct io_failure_record *failrec)
{
struct rb_node *node;
struct extent_state *state;
int ret = 0;
spin_lock(&tree->lock);
/*
* this search will find all the extents that end after
* our range starts.
*/
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->failrec = failrec;
out:
spin_unlock(&tree->lock);
return ret;
}
struct io_failure_record *get_state_failrec(struct extent_io_tree *tree, u64 start)
{
struct rb_node *node;
struct extent_state *state;
struct io_failure_record *failrec;
spin_lock(&tree->lock);
/*
* this search will find all the extents that end after
* our range starts.
*/
node = tree_search(tree, start);
if (!node) {
failrec = ERR_PTR(-ENOENT);
goto out;
}
state = rb_entry(node, struct extent_state, rb_node);
if (state->start != start) {
failrec = ERR_PTR(-ENOENT);
goto out;
}
failrec = state->failrec;
out:
spin_unlock(&tree->lock);
return failrec;
}
/*
* searches a range in the state tree for a given mask.
* If 'filled' == 1, this returns 1 only if every extent in the tree
* has the bits set. Otherwise, 1 is returned if any bit in the
* range is found set.
*/
int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
u32 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 && extent_state_in_tree(cached) && 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;
}
int free_io_failure(struct extent_io_tree *failure_tree,
struct extent_io_tree *io_tree,
struct io_failure_record *rec)
{
int ret;
int err = 0;
set_state_failrec(failure_tree, rec->start, NULL);
ret = clear_extent_bits(failure_tree, rec->start,
rec->start + rec->len - 1,
EXTENT_LOCKED | EXTENT_DIRTY);
if (ret)
err = ret;
ret = clear_extent_bits(io_tree, rec->start,
rec->start + rec->len - 1,
EXTENT_DAMAGED);
if (ret && !err)
err = ret;
kfree(rec);
return err;
}
/*
* this bypasses the standard btrfs submit functions deliberately, as
* the standard behavior is to write all copies in a raid setup. here we only
* want to write the one bad copy. so we do the mapping for ourselves and issue
* submit_bio directly.
* to avoid any synchronization issues, wait for the data after writing, which
* actually prevents the read that triggered the error from finishing.
* currently, there can be no more than two copies of every data bit. thus,
* exactly one rewrite is required.
*/
static int repair_io_failure(struct btrfs_fs_info *fs_info, u64 ino, u64 start,
u64 length, u64 logical, struct page *page,
unsigned int pg_offset, int mirror_num)
{
struct bio *bio;
struct btrfs_device *dev;
u64 map_length = 0;
u64 sector;
struct btrfs_io_context *bioc = NULL;
int ret;
ASSERT(!(fs_info->sb->s_flags & SB_RDONLY));
BUG_ON(!mirror_num);
if (btrfs_is_zoned(fs_info))
return btrfs_repair_one_zone(fs_info, logical);
bio = btrfs_bio_alloc(1);
bio->bi_iter.bi_size = 0;
map_length = length;
/*
* Avoid races with device replace and make sure our bioc has devices
* associated to its stripes that don't go away while we are doing the
* read repair operation.
*/
btrfs_bio_counter_inc_blocked(fs_info);
if (btrfs_is_parity_mirror(fs_info, logical, length)) {
/*
* Note that we don't use BTRFS_MAP_WRITE because it's supposed
* to update all raid stripes, but here we just want to correct
* bad stripe, thus BTRFS_MAP_READ is abused to only get the bad
* stripe's dev and sector.
*/
ret = btrfs_map_block(fs_info, BTRFS_MAP_READ, logical,
&map_length, &bioc, 0);
if (ret) {
btrfs_bio_counter_dec(fs_info);
bio_put(bio);
return -EIO;
}
ASSERT(bioc->mirror_num == 1);
} else {
ret = btrfs_map_block(fs_info, BTRFS_MAP_WRITE, logical,
&map_length, &bioc, mirror_num);
if (ret) {
btrfs_bio_counter_dec(fs_info);
bio_put(bio);
return -EIO;
}
BUG_ON(mirror_num != bioc->mirror_num);
}
sector = bioc->stripes[bioc->mirror_num - 1].physical >> 9;
bio->bi_iter.bi_sector = sector;
dev = bioc->stripes[bioc->mirror_num - 1].dev;
btrfs_put_bioc(bioc);
if (!dev || !dev->bdev ||
!test_bit(BTRFS_DEV_STATE_WRITEABLE, &dev->dev_state)) {
btrfs_bio_counter_dec(fs_info);
bio_put(bio);
return -EIO;
}
bio_set_dev(bio, dev->bdev);
bio->bi_opf = REQ_OP_WRITE | REQ_SYNC;
bio_add_page(bio, page, length, pg_offset);
if (btrfsic_submit_bio_wait(bio)) {
/* try to remap that extent elsewhere? */
btrfs_bio_counter_dec(fs_info);
bio_put(bio);
btrfs_dev_stat_inc_and_print(dev, BTRFS_DEV_STAT_WRITE_ERRS);
return -EIO;
}
btrfs_info_rl_in_rcu(fs_info,
"read error corrected: ino %llu off %llu (dev %s sector %llu)",
ino, start,
rcu_str_deref(dev->name), sector);
btrfs_bio_counter_dec(fs_info);
bio_put(bio);
return 0;
}
int btrfs_repair_eb_io_failure(const struct extent_buffer *eb, int mirror_num)
{
struct btrfs_fs_info *fs_info = eb->fs_info;
u64 start = eb->start;
int i, num_pages = num_extent_pages(eb);
int ret = 0;
if (sb_rdonly(fs_info->sb))
return -EROFS;
for (i = 0; i < num_pages; i++) {
struct page *p = eb->pages[i];
ret = repair_io_failure(fs_info, 0, start, PAGE_SIZE, start, p,
start - page_offset(p), mirror_num);
if (ret)
break;
start += PAGE_SIZE;
}
return ret;
}
/*
* each time an IO finishes, we do a fast check in the IO failure tree
* to see if we need to process or clean up an io_failure_record
*/
int clean_io_failure(struct btrfs_fs_info *fs_info,
struct extent_io_tree *failure_tree,
struct extent_io_tree *io_tree, u64 start,
struct page *page, u64 ino, unsigned int pg_offset)
{
u64 private;
struct io_failure_record *failrec;
struct extent_state *state;
int num_copies;
int ret;
private = 0;
ret = count_range_bits(failure_tree, &private, (u64)-1, 1,
EXTENT_DIRTY, 0);
if (!ret)
return 0;
failrec = get_state_failrec(failure_tree, start);
if (IS_ERR(failrec))
return 0;
BUG_ON(!failrec->this_mirror);
if (sb_rdonly(fs_info->sb))
goto out;
spin_lock(&io_tree->lock);
state = find_first_extent_bit_state(io_tree,
failrec->start,
EXTENT_LOCKED);
spin_unlock(&io_tree->lock);
if (state && state->start <= failrec->start &&
state->end >= failrec->start + failrec->len - 1) {
num_copies = btrfs_num_copies(fs_info, failrec->logical,
failrec->len);
if (num_copies > 1) {
repair_io_failure(fs_info, ino, start, failrec->len,
failrec->logical, page, pg_offset,
failrec->failed_mirror);
}
}
out:
free_io_failure(failure_tree, io_tree, failrec);
return 0;
}
/*
* Can be called when
* - hold extent lock
* - under ordered extent
* - the inode is freeing
*/
void btrfs_free_io_failure_record(struct btrfs_inode *inode, u64 start, u64 end)
{
struct extent_io_tree *failure_tree = &inode->io_failure_tree;
struct io_failure_record *failrec;
struct extent_state *state, *next;
if (RB_EMPTY_ROOT(&failure_tree->state))
return;
spin_lock(&failure_tree->lock);
state = find_first_extent_bit_state(failure_tree, start, EXTENT_DIRTY);
while (state) {
if (state->start > end)
break;
ASSERT(state->end <= end);
next = next_state(state);
failrec = state->failrec;
free_extent_state(state);
kfree(failrec);
state = next;
}
spin_unlock(&failure_tree->lock);
}
static struct io_failure_record *btrfs_get_io_failure_record(struct inode *inode,
u64 start)
{
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
struct io_failure_record *failrec;
struct extent_map *em;
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;
const u32 sectorsize = fs_info->sectorsize;
int ret;
u64 logical;
failrec = get_state_failrec(failure_tree, start);
if (!IS_ERR(failrec)) {
btrfs_debug(fs_info,
"Get IO Failure Record: (found) logical=%llu, start=%llu, len=%llu",
failrec->logical, failrec->start, failrec->len);
/*
* when data can be on disk more than twice, add to failrec here
* (e.g. with a list for failed_mirror) to make
* clean_io_failure() clean all those errors at once.
*/
return failrec;
}
failrec = kzalloc(sizeof(*failrec), GFP_NOFS);
if (!failrec)
return ERR_PTR(-ENOMEM);
failrec->start = start;
failrec->len = sectorsize;
failrec->this_mirror = 0;
failrec->bio_flags = 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 ERR_PTR(-EIO);
}
if (em->start > start || em->start + em->len <= start) {
free_extent_map(em);
em = NULL;
}
read_unlock(&em_tree->lock);
if (!em) {
kfree(failrec);
return ERR_PTR(-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);
}
btrfs_debug(fs_info,
"Get IO Failure Record: (new) logical=%llu, start=%llu, len=%llu",
logical, start, failrec->len);
failrec->logical = logical;
free_extent_map(em);
/* Set the bits in the private failure tree */
ret = set_extent_bits(failure_tree, start, start + sectorsize - 1,
EXTENT_LOCKED | EXTENT_DIRTY);
if (ret >= 0) {
ret = set_state_failrec(failure_tree, start, failrec);
/* Set the bits in the inode's tree */
ret = set_extent_bits(tree, start, start + sectorsize - 1,
EXTENT_DAMAGED);
} else if (ret < 0) {
kfree(failrec);
return ERR_PTR(ret);
}
return failrec;
}
static bool btrfs_check_repairable(struct inode *inode,
struct io_failure_record *failrec,
int failed_mirror)
{
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
int num_copies;
num_copies = btrfs_num_copies(fs_info, failrec->logical, failrec->len);
if (num_copies == 1) {
/*
* we only have a single copy of the data, so don't bother with
* all the retry and error correction code that follows. no
* matter what the error is, it is very likely to persist.
*/
btrfs_debug(fs_info,
"Check Repairable: cannot repair, num_copies=%d, next_mirror %d, failed_mirror %d",
num_copies, failrec->this_mirror, failed_mirror);
return false;
}
/* The failure record should only contain one sector */
ASSERT(failrec->len == fs_info->sectorsize);
/*
* There are two premises:
* a) deliver good data to the caller
* b) correct the bad sectors on disk
*
* Since we're only doing repair for one sector, we only need to get
* a good copy of the failed sector and if we succeed, we have setup
* everything for repair_io_failure to do the rest for us.
*/
failrec->failed_mirror = failed_mirror;
failrec->this_mirror++;
if (failrec->this_mirror == failed_mirror)
failrec->this_mirror++;
if (failrec->this_mirror > num_copies) {
btrfs_debug(fs_info,
"Check Repairable: (fail) num_copies=%d, next_mirror %d, failed_mirror %d",
num_copies, failrec->this_mirror, failed_mirror);
return false;
}
return true;
}
int btrfs_repair_one_sector(struct inode *inode,
struct bio *failed_bio, u32 bio_offset,
struct page *page, unsigned int pgoff,
u64 start, int failed_mirror,
submit_bio_hook_t *submit_bio_hook)
{
struct io_failure_record *failrec;
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
struct extent_io_tree *failure_tree = &BTRFS_I(inode)->io_failure_tree;
struct btrfs_bio *failed_bbio = btrfs_bio(failed_bio);
const int icsum = bio_offset >> fs_info->sectorsize_bits;
struct bio *repair_bio;
struct btrfs_bio *repair_bbio;
blk_status_t status;
btrfs_debug(fs_info,
"repair read error: read error at %llu", start);
BUG_ON(bio_op(failed_bio) == REQ_OP_WRITE);
failrec = btrfs_get_io_failure_record(inode, start);
if (IS_ERR(failrec))
return PTR_ERR(failrec);
if (!btrfs_check_repairable(inode, failrec, failed_mirror)) {
free_io_failure(failure_tree, tree, failrec);
return -EIO;
}
repair_bio = btrfs_bio_alloc(1);
repair_bbio = btrfs_bio(repair_bio);
repair_bio->bi_opf = REQ_OP_READ;
repair_bio->bi_end_io = failed_bio->bi_end_io;
repair_bio->bi_iter.bi_sector = failrec->logical >> 9;
repair_bio->bi_private = failed_bio->bi_private;
if (failed_bbio->csum) {
const u32 csum_size = fs_info->csum_size;
repair_bbio->csum = repair_bbio->csum_inline;
memcpy(repair_bbio->csum,
failed_bbio->csum + csum_size * icsum, csum_size);
}
bio_add_page(repair_bio, page, failrec->len, pgoff);
repair_bbio->iter = repair_bio->bi_iter;
btrfs_debug(btrfs_sb(inode->i_sb),
"repair read error: submitting new read to mirror %d",
failrec->this_mirror);
status = submit_bio_hook(inode, repair_bio, failrec->this_mirror,
failrec->bio_flags);
if (status) {
free_io_failure(failure_tree, tree, failrec);
bio_put(repair_bio);
}
return blk_status_to_errno(status);
}
static void end_page_read(struct page *page, bool uptodate, u64 start, u32 len)
{
struct btrfs_fs_info *fs_info = btrfs_sb(page->mapping->host->i_sb);
ASSERT(page_offset(page) <= start &&
start + len <= page_offset(page) + PAGE_SIZE);
if (uptodate) {
if (fsverity_active(page->mapping->host) &&
!PageError(page) &&
!PageUptodate(page) &&
start < i_size_read(page->mapping->host) &&
!fsverity_verify_page(page)) {
btrfs_page_set_error(fs_info, page, start, len);
} else {
btrfs_page_set_uptodate(fs_info, page, start, len);
}
} else {
btrfs_page_clear_uptodate(fs_info, page, start, len);
btrfs_page_set_error(fs_info, page, start, len);
}
if (fs_info->sectorsize == PAGE_SIZE)
unlock_page(page);
else
btrfs_subpage_end_reader(fs_info, page, start, len);
}
static blk_status_t submit_read_repair(struct inode *inode,
struct bio *failed_bio, u32 bio_offset,
struct page *page, unsigned int pgoff,
u64 start, u64 end, int failed_mirror,
unsigned int error_bitmap,
submit_bio_hook_t *submit_bio_hook)
{
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
const u32 sectorsize = fs_info->sectorsize;
const int nr_bits = (end + 1 - start) >> fs_info->sectorsize_bits;
int error = 0;
int i;
BUG_ON(bio_op(failed_bio) == REQ_OP_WRITE);
/* We're here because we had some read errors or csum mismatch */
ASSERT(error_bitmap);
/*
* We only get called on buffered IO, thus page must be mapped and bio
* must not be cloned.
*/
ASSERT(page->mapping && !bio_flagged(failed_bio, BIO_CLONED));
/* Iterate through all the sectors in the range */
for (i = 0; i < nr_bits; i++) {
const unsigned int offset = i * sectorsize;
struct extent_state *cached = NULL;
bool uptodate = false;
int ret;
if (!(error_bitmap & (1U << i))) {
/*
* This sector has no error, just end the page read
* and unlock the range.
*/
uptodate = true;
goto next;
}
ret = btrfs_repair_one_sector(inode, failed_bio,
bio_offset + offset,
page, pgoff + offset, start + offset,
failed_mirror, submit_bio_hook);
if (!ret) {
/*
* We have submitted the read repair, the page release
* will be handled by the endio function of the
* submitted repair bio.
* Thus we don't need to do any thing here.
*/
continue;
}
/*
* Repair failed, just record the error but still continue.
* Or the remaining sectors will not be properly unlocked.
*/
if (!error)
error = ret;
next:
end_page_read(page, uptodate, start + offset, sectorsize);
if (uptodate)
set_extent_uptodate(&BTRFS_I(inode)->io_tree,
start + offset,
start + offset + sectorsize - 1,
&cached, GFP_ATOMIC);
unlock_extent_cached_atomic(&BTRFS_I(inode)->io_tree,
start + offset,
start + offset + sectorsize - 1,
&cached);
}
return errno_to_blk_status(error);
}
/* lots and lots of room for performance fixes in the end_bio funcs */
void end_extent_writepage(struct page *page, int err, u64 start, u64 end)
{
struct btrfs_inode *inode;
const bool uptodate = (err == 0);
int ret = 0;
ASSERT(page && page->mapping);
inode = BTRFS_I(page->mapping->host);
btrfs_writepage_endio_finish_ordered(inode, page, start, end, uptodate);
if (!uptodate) {
const struct btrfs_fs_info *fs_info = inode->root->fs_info;
u32 len;