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authorChris Mason <chris.mason@oracle.com>2011-11-06 03:05:08 -0500
committerChris Mason <chris.mason@oracle.com>2011-11-06 03:05:08 -0500
commit531f4b1ae5e0fc8c9b3f03838218e5ea178f80d3 (patch)
tree63efdfe9b192243fefb76be3921b9a2aaa26291e /fs
parentc06a0e120a4e381a1c291c1fce3c6155c5791cae (diff)
parent7a26285eea8eb92e0088db011571d887d4551b0f (diff)
downloadlinux-stericsson-531f4b1ae5e0fc8c9b3f03838218e5ea178f80d3.tar.gz
Merge branch 'for-chris' of git://github.com/sensille/linux into integration
Conflicts: fs/btrfs/ctree.h Signed-off-by: Chris Mason <chris.mason@oracle.com>
Diffstat (limited to 'fs')
-rw-r--r--fs/btrfs/Makefile3
-rw-r--r--fs/btrfs/ctree.h21
-rw-r--r--fs/btrfs/disk-io.c84
-rw-r--r--fs/btrfs/disk-io.h2
-rw-r--r--fs/btrfs/extent_io.c9
-rw-r--r--fs/btrfs/extent_io.h4
-rw-r--r--fs/btrfs/reada.c949
-rw-r--r--fs/btrfs/scrub.c112
-rw-r--r--fs/btrfs/volumes.c8
-rw-r--r--fs/btrfs/volumes.h8
10 files changed, 1130 insertions, 70 deletions
diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile
index 40e6ac08c21f..bdd6fb238ce1 100644
--- a/fs/btrfs/Makefile
+++ b/fs/btrfs/Makefile
@@ -7,6 +7,7 @@ btrfs-y += super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \
extent_map.o sysfs.o struct-funcs.o xattr.o ordered-data.o \
extent_io.o volumes.o async-thread.o ioctl.o locking.o orphan.o \
export.o tree-log.o free-space-cache.o zlib.o lzo.o \
- compression.o delayed-ref.o relocation.o delayed-inode.o scrub.o
+ compression.o delayed-ref.o relocation.o delayed-inode.o scrub.o \
+ reada.o
btrfs-$(CONFIG_BTRFS_FS_POSIX_ACL) += acl.o
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 6bb34fc1ff22..b9ba59ff9292 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1074,6 +1074,7 @@ struct btrfs_fs_info {
struct btrfs_workers endio_freespace_worker;
struct btrfs_workers submit_workers;
struct btrfs_workers caching_workers;
+ struct btrfs_workers readahead_workers;
/*
* fixup workers take dirty pages that didn't properly go through
@@ -1158,6 +1159,10 @@ struct btrfs_fs_info {
struct btrfs_delayed_root *delayed_root;
+ /* readahead tree */
+ spinlock_t reada_lock;
+ struct radix_tree_root reada_tree;
+
/* next backup root to be overwritten */
int backup_root_index;
};
@@ -2812,4 +2817,20 @@ int btrfs_scrub_cancel_devid(struct btrfs_root *root, u64 devid);
int btrfs_scrub_progress(struct btrfs_root *root, u64 devid,
struct btrfs_scrub_progress *progress);
+/* reada.c */
+struct reada_control {
+ struct btrfs_root *root; /* tree to prefetch */
+ struct btrfs_key key_start;
+ struct btrfs_key key_end; /* exclusive */
+ atomic_t elems;
+ struct kref refcnt;
+ wait_queue_head_t wait;
+};
+struct reada_control *btrfs_reada_add(struct btrfs_root *root,
+ struct btrfs_key *start, struct btrfs_key *end);
+int btrfs_reada_wait(void *handle);
+void btrfs_reada_detach(void *handle);
+int btree_readahead_hook(struct btrfs_root *root, struct extent_buffer *eb,
+ u64 start, int err);
+
#endif
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 23b6776477b7..cedfbfb278eb 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -366,7 +366,8 @@ static int btree_read_extent_buffer_pages(struct btrfs_root *root,
clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags);
io_tree = &BTRFS_I(root->fs_info->btree_inode)->io_tree;
while (1) {
- ret = read_extent_buffer_pages(io_tree, eb, start, 1,
+ ret = read_extent_buffer_pages(io_tree, eb, start,
+ WAIT_COMPLETE,
btree_get_extent, mirror_num);
if (!ret &&
!verify_parent_transid(io_tree, eb, parent_transid))
@@ -607,11 +608,47 @@ static int btree_readpage_end_io_hook(struct page *page, u64 start, u64 end,
end = min_t(u64, eb->len, PAGE_CACHE_SIZE);
end = eb->start + end - 1;
err:
+ if (test_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags)) {
+ clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags);
+ btree_readahead_hook(root, eb, eb->start, ret);
+ }
+
free_extent_buffer(eb);
out:
return ret;
}
+static int btree_io_failed_hook(struct bio *failed_bio,
+ struct page *page, u64 start, u64 end,
+ struct extent_state *state)
+{
+ struct extent_io_tree *tree;
+ unsigned long len;
+ struct extent_buffer *eb;
+ struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
+
+ tree = &BTRFS_I(page->mapping->host)->io_tree;
+ if (page->private == EXTENT_PAGE_PRIVATE)
+ goto out;
+ if (!page->private)
+ goto out;
+
+ len = page->private >> 2;
+ WARN_ON(len == 0);
+
+ eb = alloc_extent_buffer(tree, start, len, page);
+ if (eb == NULL)
+ goto out;
+
+ if (test_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags)) {
+ clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags);
+ btree_readahead_hook(root, eb, eb->start, -EIO);
+ }
+
+out:
+ return -EIO; /* we fixed nothing */
+}
+
static void end_workqueue_bio(struct bio *bio, int err)
{
struct end_io_wq *end_io_wq = bio->bi_private;
@@ -973,11 +1010,43 @@ int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
if (!buf)
return 0;
read_extent_buffer_pages(&BTRFS_I(btree_inode)->io_tree,
- buf, 0, 0, btree_get_extent, 0);
+ buf, 0, WAIT_NONE, btree_get_extent, 0);
free_extent_buffer(buf);
return ret;
}
+int reada_tree_block_flagged(struct btrfs_root *root, u64 bytenr, u32 blocksize,
+ int mirror_num, struct extent_buffer **eb)
+{
+ struct extent_buffer *buf = NULL;
+ struct inode *btree_inode = root->fs_info->btree_inode;
+ struct extent_io_tree *io_tree = &BTRFS_I(btree_inode)->io_tree;
+ int ret;
+
+ buf = btrfs_find_create_tree_block(root, bytenr, blocksize);
+ if (!buf)
+ return 0;
+
+ set_bit(EXTENT_BUFFER_READAHEAD, &buf->bflags);
+
+ ret = read_extent_buffer_pages(io_tree, buf, 0, WAIT_PAGE_LOCK,
+ btree_get_extent, mirror_num);
+ if (ret) {
+ free_extent_buffer(buf);
+ return ret;
+ }
+
+ if (test_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags)) {
+ free_extent_buffer(buf);
+ return -EIO;
+ } else if (extent_buffer_uptodate(io_tree, buf, NULL)) {
+ *eb = buf;
+ } else {
+ free_extent_buffer(buf);
+ }
+ return 0;
+}
+
struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
u64 bytenr, u32 blocksize)
{
@@ -1904,6 +1973,10 @@ struct btrfs_root *open_ctree(struct super_block *sb,
fs_info->trans_no_join = 0;
fs_info->free_chunk_space = 0;
+ /* readahead state */
+ INIT_RADIX_TREE(&fs_info->reada_tree, GFP_NOFS & ~__GFP_WAIT);
+ spin_lock_init(&fs_info->reada_lock);
+
fs_info->thread_pool_size = min_t(unsigned long,
num_online_cpus() + 2, 8);
@@ -2103,6 +2176,9 @@ struct btrfs_root *open_ctree(struct super_block *sb,
btrfs_init_workers(&fs_info->delayed_workers, "delayed-meta",
fs_info->thread_pool_size,
&fs_info->generic_worker);
+ btrfs_init_workers(&fs_info->readahead_workers, "readahead",
+ fs_info->thread_pool_size,
+ &fs_info->generic_worker);
/*
* endios are largely parallel and should have a very
@@ -2113,6 +2189,7 @@ struct btrfs_root *open_ctree(struct super_block *sb,
fs_info->endio_write_workers.idle_thresh = 2;
fs_info->endio_meta_write_workers.idle_thresh = 2;
+ fs_info->readahead_workers.idle_thresh = 2;
btrfs_start_workers(&fs_info->workers, 1);
btrfs_start_workers(&fs_info->generic_worker, 1);
@@ -2126,6 +2203,7 @@ struct btrfs_root *open_ctree(struct super_block *sb,
btrfs_start_workers(&fs_info->endio_freespace_worker, 1);
btrfs_start_workers(&fs_info->delayed_workers, 1);
btrfs_start_workers(&fs_info->caching_workers, 1);
+ btrfs_start_workers(&fs_info->readahead_workers, 1);
fs_info->bdi.ra_pages *= btrfs_super_num_devices(disk_super);
fs_info->bdi.ra_pages = max(fs_info->bdi.ra_pages,
@@ -2855,6 +2933,7 @@ int close_ctree(struct btrfs_root *root)
btrfs_stop_workers(&fs_info->submit_workers);
btrfs_stop_workers(&fs_info->delayed_workers);
btrfs_stop_workers(&fs_info->caching_workers);
+ btrfs_stop_workers(&fs_info->readahead_workers);
btrfs_close_devices(fs_info->fs_devices);
btrfs_mapping_tree_free(&fs_info->mapping_tree);
@@ -3363,6 +3442,7 @@ static int btrfs_cleanup_transaction(struct btrfs_root *root)
static struct extent_io_ops btree_extent_io_ops = {
.write_cache_pages_lock_hook = btree_lock_page_hook,
.readpage_end_io_hook = btree_readpage_end_io_hook,
+ .readpage_io_failed_hook = btree_io_failed_hook,
.submit_bio_hook = btree_submit_bio_hook,
/* note we're sharing with inode.c for the merge bio hook */
.merge_bio_hook = btrfs_merge_bio_hook,
diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h
index e678539c8519..c99d0a8f13fa 100644
--- a/fs/btrfs/disk-io.h
+++ b/fs/btrfs/disk-io.h
@@ -40,6 +40,8 @@ struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
u32 blocksize, u64 parent_transid);
int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
u64 parent_transid);
+int reada_tree_block_flagged(struct btrfs_root *root, u64 bytenr, u32 blocksize,
+ int mirror_num, struct extent_buffer **eb);
struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
u64 bytenr, u32 blocksize);
int clean_tree_block(struct btrfs_trans_handle *trans,
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index cc3c58970d4e..c12705682c65 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -1919,7 +1919,7 @@ static void end_bio_extent_readpage(struct bio *bio, int err)
if (!uptodate && tree->ops &&
tree->ops->readpage_io_failed_hook) {
ret = tree->ops->readpage_io_failed_hook(bio, page,
- start, end, NULL);
+ start, end, state);
if (ret == 0) {
uptodate =
test_bit(BIO_UPTODATE, &bio->bi_flags);
@@ -3551,8 +3551,7 @@ int extent_buffer_uptodate(struct extent_io_tree *tree,
}
int read_extent_buffer_pages(struct extent_io_tree *tree,
- struct extent_buffer *eb,
- u64 start, int wait,
+ struct extent_buffer *eb, u64 start, int wait,
get_extent_t *get_extent, int mirror_num)
{
unsigned long i;
@@ -3588,7 +3587,7 @@ int read_extent_buffer_pages(struct extent_io_tree *tree,
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) {
+ if (wait == WAIT_NONE) {
if (!trylock_page(page))
goto unlock_exit;
} else {
@@ -3632,7 +3631,7 @@ int read_extent_buffer_pages(struct extent_io_tree *tree,
if (bio)
submit_one_bio(READ, bio, mirror_num, bio_flags);
- if (ret || !wait)
+ if (ret || wait != WAIT_COMPLETE)
return ret;
for (i = start_i; i < num_pages; i++) {
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index cbd4824a7c94..697570eed9e8 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -33,6 +33,7 @@
#define EXTENT_BUFFER_BLOCKING 1
#define EXTENT_BUFFER_DIRTY 2
#define EXTENT_BUFFER_CORRUPT 3
+#define EXTENT_BUFFER_READAHEAD 4 /* this got triggered by readahead */
/* these are flags for extent_clear_unlock_delalloc */
#define EXTENT_CLEAR_UNLOCK_PAGE 0x1
@@ -252,6 +253,9 @@ struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree,
struct extent_buffer *find_extent_buffer(struct extent_io_tree *tree,
u64 start, unsigned long len);
void free_extent_buffer(struct extent_buffer *eb);
+#define WAIT_NONE 0
+#define WAIT_COMPLETE 1
+#define WAIT_PAGE_LOCK 2
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);
diff --git a/fs/btrfs/reada.c b/fs/btrfs/reada.c
new file mode 100644
index 000000000000..2b701d082227
--- /dev/null
+++ b/fs/btrfs/reada.c
@@ -0,0 +1,949 @@
+/*
+ * Copyright (C) 2011 STRATO. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#include <linux/sched.h>
+#include <linux/pagemap.h>
+#include <linux/writeback.h>
+#include <linux/blkdev.h>
+#include <linux/rbtree.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+#include "ctree.h"
+#include "volumes.h"
+#include "disk-io.h"
+#include "transaction.h"
+
+#undef DEBUG
+
+/*
+ * This is the implementation for the generic read ahead framework.
+ *
+ * To trigger a readahead, btrfs_reada_add must be called. It will start
+ * a read ahead for the given range [start, end) on tree root. The returned
+ * handle can either be used to wait on the readahead to finish
+ * (btrfs_reada_wait), or to send it to the background (btrfs_reada_detach).
+ *
+ * The read ahead works as follows:
+ * On btrfs_reada_add, the root of the tree is inserted into a radix_tree.
+ * reada_start_machine will then search for extents to prefetch and trigger
+ * some reads. When a read finishes for a node, all contained node/leaf
+ * pointers that lie in the given range will also be enqueued. The reads will
+ * be triggered in sequential order, thus giving a big win over a naive
+ * enumeration. It will also make use of multi-device layouts. Each disk
+ * will have its on read pointer and all disks will by utilized in parallel.
+ * Also will no two disks read both sides of a mirror simultaneously, as this
+ * would waste seeking capacity. Instead both disks will read different parts
+ * of the filesystem.
+ * Any number of readaheads can be started in parallel. The read order will be
+ * determined globally, i.e. 2 parallel readaheads will normally finish faster
+ * than the 2 started one after another.
+ */
+
+#define MAX_MIRRORS 2
+#define MAX_IN_FLIGHT 6
+
+struct reada_extctl {
+ struct list_head list;
+ struct reada_control *rc;
+ u64 generation;
+};
+
+struct reada_extent {
+ u64 logical;
+ struct btrfs_key top;
+ u32 blocksize;
+ int err;
+ struct list_head extctl;
+ struct kref refcnt;
+ spinlock_t lock;
+ struct reada_zone *zones[MAX_MIRRORS];
+ int nzones;
+ struct btrfs_device *scheduled_for;
+};
+
+struct reada_zone {
+ u64 start;
+ u64 end;
+ u64 elems;
+ struct list_head list;
+ spinlock_t lock;
+ int locked;
+ struct btrfs_device *device;
+ struct btrfs_device *devs[MAX_MIRRORS]; /* full list, incl self */
+ int ndevs;
+ struct kref refcnt;
+};
+
+struct reada_machine_work {
+ struct btrfs_work work;
+ struct btrfs_fs_info *fs_info;
+};
+
+static void reada_extent_put(struct btrfs_fs_info *, struct reada_extent *);
+static void reada_control_release(struct kref *kref);
+static void reada_zone_release(struct kref *kref);
+static void reada_start_machine(struct btrfs_fs_info *fs_info);
+static void __reada_start_machine(struct btrfs_fs_info *fs_info);
+
+static int reada_add_block(struct reada_control *rc, u64 logical,
+ struct btrfs_key *top, int level, u64 generation);
+
+/* recurses */
+/* in case of err, eb might be NULL */
+static int __readahead_hook(struct btrfs_root *root, struct extent_buffer *eb,
+ u64 start, int err)
+{
+ int level = 0;
+ int nritems;
+ int i;
+ u64 bytenr;
+ u64 generation;
+ struct reada_extent *re;
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ struct list_head list;
+ unsigned long index = start >> PAGE_CACHE_SHIFT;
+ struct btrfs_device *for_dev;
+
+ if (eb)
+ level = btrfs_header_level(eb);
+
+ /* find extent */
+ spin_lock(&fs_info->reada_lock);
+ re = radix_tree_lookup(&fs_info->reada_tree, index);
+ if (re)
+ kref_get(&re->refcnt);
+ spin_unlock(&fs_info->reada_lock);
+
+ if (!re)
+ return -1;
+
+ spin_lock(&re->lock);
+ /*
+ * just take the full list from the extent. afterwards we
+ * don't need the lock anymore
+ */
+ list_replace_init(&re->extctl, &list);
+ for_dev = re->scheduled_for;
+ re->scheduled_for = NULL;
+ spin_unlock(&re->lock);
+
+ if (err == 0) {
+ nritems = level ? btrfs_header_nritems(eb) : 0;
+ generation = btrfs_header_generation(eb);
+ /*
+ * FIXME: currently we just set nritems to 0 if this is a leaf,
+ * effectively ignoring the content. In a next step we could
+ * trigger more readahead depending from the content, e.g.
+ * fetch the checksums for the extents in the leaf.
+ */
+ } else {
+ /*
+ * this is the error case, the extent buffer has not been
+ * read correctly. We won't access anything from it and
+ * just cleanup our data structures. Effectively this will
+ * cut the branch below this node from read ahead.
+ */
+ nritems = 0;
+ generation = 0;
+ }
+
+ for (i = 0; i < nritems; i++) {
+ struct reada_extctl *rec;
+ u64 n_gen;
+ struct btrfs_key key;
+ struct btrfs_key next_key;
+
+ btrfs_node_key_to_cpu(eb, &key, i);
+ if (i + 1 < nritems)
+ btrfs_node_key_to_cpu(eb, &next_key, i + 1);
+ else
+ next_key = re->top;
+ bytenr = btrfs_node_blockptr(eb, i);
+ n_gen = btrfs_node_ptr_generation(eb, i);
+
+ list_for_each_entry(rec, &list, list) {
+ struct reada_control *rc = rec->rc;
+
+ /*
+ * if the generation doesn't match, just ignore this
+ * extctl. This will probably cut off a branch from
+ * prefetch. Alternatively one could start a new (sub-)
+ * prefetch for this branch, starting again from root.
+ * FIXME: move the generation check out of this loop
+ */
+#ifdef DEBUG
+ if (rec->generation != generation) {
+ printk(KERN_DEBUG "generation mismatch for "
+ "(%llu,%d,%llu) %llu != %llu\n",
+ key.objectid, key.type, key.offset,
+ rec->generation, generation);
+ }
+#endif
+ if (rec->generation == generation &&
+ btrfs_comp_cpu_keys(&key, &rc->key_end) < 0 &&
+ btrfs_comp_cpu_keys(&next_key, &rc->key_start) > 0)
+ reada_add_block(rc, bytenr, &next_key,
+ level - 1, n_gen);
+ }
+ }
+ /*
+ * free extctl records
+ */
+ while (!list_empty(&list)) {
+ struct reada_control *rc;
+ struct reada_extctl *rec;
+
+ rec = list_first_entry(&list, struct reada_extctl, list);
+ list_del(&rec->list);
+ rc = rec->rc;
+ kfree(rec);
+
+ kref_get(&rc->refcnt);
+ if (atomic_dec_and_test(&rc->elems)) {
+ kref_put(&rc->refcnt, reada_control_release);
+ wake_up(&rc->wait);
+ }
+ kref_put(&rc->refcnt, reada_control_release);
+
+ reada_extent_put(fs_info, re); /* one ref for each entry */
+ }
+ reada_extent_put(fs_info, re); /* our ref */
+ if (for_dev)
+ atomic_dec(&for_dev->reada_in_flight);
+
+ return 0;
+}
+
+/*
+ * start is passed separately in case eb in NULL, which may be the case with
+ * failed I/O
+ */
+int btree_readahead_hook(struct btrfs_root *root, struct extent_buffer *eb,
+ u64 start, int err)
+{
+ int ret;
+
+ ret = __readahead_hook(root, eb, start, err);
+
+ reada_start_machine(root->fs_info);
+
+ return ret;
+}
+
+static struct reada_zone *reada_find_zone(struct btrfs_fs_info *fs_info,
+ struct btrfs_device *dev, u64 logical,
+ struct btrfs_multi_bio *multi)
+{
+ int ret;
+ int looped = 0;
+ struct reada_zone *zone;
+ struct btrfs_block_group_cache *cache = NULL;
+ u64 start;
+ u64 end;
+ int i;
+
+again:
+ zone = NULL;
+ spin_lock(&fs_info->reada_lock);
+ ret = radix_tree_gang_lookup(&dev->reada_zones, (void **)&zone,
+ logical >> PAGE_CACHE_SHIFT, 1);
+ if (ret == 1)
+ kref_get(&zone->refcnt);
+ spin_unlock(&fs_info->reada_lock);
+
+ if (ret == 1) {
+ if (logical >= zone->start && logical < zone->end)
+ return zone;
+ spin_lock(&fs_info->reada_lock);
+ kref_put(&zone->refcnt, reada_zone_release);
+ spin_unlock(&fs_info->reada_lock);
+ }
+
+ if (looped)
+ return NULL;
+
+ cache = btrfs_lookup_block_group(fs_info, logical);
+ if (!cache)
+ return NULL;
+
+ start = cache->key.objectid;
+ end = start + cache->key.offset - 1;
+ btrfs_put_block_group(cache);
+
+ zone = kzalloc(sizeof(*zone), GFP_NOFS);
+ if (!zone)
+ return NULL;
+
+ zone->start = start;
+ zone->end = end;
+ INIT_LIST_HEAD(&zone->list);
+ spin_lock_init(&zone->lock);
+ zone->locked = 0;
+ kref_init(&zone->refcnt);
+ zone->elems = 0;
+ zone->device = dev; /* our device always sits at index 0 */
+ for (i = 0; i < multi->num_stripes; ++i) {
+ /* bounds have already been checked */
+ zone->devs[i] = multi->stripes[i].dev;
+ }
+ zone->ndevs = multi->num_stripes;
+
+ spin_lock(&fs_info->reada_lock);
+ ret = radix_tree_insert(&dev->reada_zones,
+ (unsigned long)zone->end >> PAGE_CACHE_SHIFT,
+ zone);
+ spin_unlock(&fs_info->reada_lock);
+
+ if (ret) {
+ kfree(zone);
+ looped = 1;
+ goto again;
+ }
+
+ return zone;
+}
+
+static struct reada_extent *reada_find_extent(struct btrfs_root *root,
+ u64 logical,
+ struct btrfs_key *top, int level)
+{
+ int ret;
+ int looped = 0;
+ struct reada_extent *re = NULL;
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ struct btrfs_mapping_tree *map_tree = &fs_info->mapping_tree;
+ struct btrfs_multi_bio *multi = NULL;
+ struct btrfs_device *dev;
+ u32 blocksize;
+ u64 length;
+ int nzones = 0;
+ int i;
+ unsigned long index = logical >> PAGE_CACHE_SHIFT;
+
+again:
+ spin_lock(&fs_info->reada_lock);
+ re = radix_tree_lookup(&fs_info->reada_tree, index);
+ if (re)
+ kref_get(&re->refcnt);
+ spin_unlock(&fs_info->reada_lock);
+
+ if (re || looped)
+ return re;
+
+ re = kzalloc(sizeof(*re), GFP_NOFS);
+ if (!re)
+ return NULL;
+
+ blocksize = btrfs_level_size(root, level);
+ re->logical = logical;
+ re->blocksize = blocksize;
+ re->top = *top;
+ INIT_LIST_HEAD(&re->extctl);
+ spin_lock_init(&re->lock);
+ kref_init(&re->refcnt);
+
+ /*
+ * map block
+ */
+ length = blocksize;
+ ret = btrfs_map_block(map_tree, REQ_WRITE, logical, &length, &multi, 0);
+ if (ret || !multi || length < blocksize)
+ goto error;
+
+ if (multi->num_stripes > MAX_MIRRORS) {
+ printk(KERN_ERR "btrfs readahead: more than %d copies not "
+ "supported", MAX_MIRRORS);
+ goto error;
+ }
+
+ for (nzones = 0; nzones < multi->num_stripes; ++nzones) {
+ struct reada_zone *zone;
+
+ dev = multi->stripes[nzones].dev;
+ zone = reada_find_zone(fs_info, dev, logical, multi);
+ if (!zone)
+ break;
+
+ re->zones[nzones] = zone;
+ spin_lock(&zone->lock);
+ if (!zone->elems)
+ kref_get(&zone->refcnt);
+ ++zone->elems;
+ spin_unlock(&zone->lock);
+ spin_lock(&fs_info->reada_lock);
+ kref_put(&zone->refcnt, reada_zone_release);
+ spin_unlock(&fs_info->reada_lock);
+ }
+ re->nzones = nzones;
+ if (nzones == 0) {
+ /* not a single zone found, error and out */
+ goto error;
+ }
+
+ /* insert extent in reada_tree + all per-device trees, all or nothing */
+ spin_lock(&fs_info->reada_lock);
+ ret = radix_tree_insert(&fs_info->reada_tree, index, re);
+ if (ret) {
+ spin_unlock(&fs_info->reada_lock);
+ if (ret != -ENOMEM) {
+ /* someone inserted the extent in the meantime */
+ looped = 1;
+ }
+ goto error;
+ }
+ for (i = 0; i < nzones; ++i) {
+ dev = multi->stripes[i].dev;
+ ret = radix_tree_insert(&dev->reada_extents, index, re);
+ if (ret) {
+ while (--i >= 0) {
+ dev = multi->stripes[i].dev;
+ BUG_ON(dev == NULL);
+ radix_tree_delete(&dev->reada_extents, index);
+ }
+ BUG_ON(fs_info == NULL);
+ radix_tree_delete(&fs_info->reada_tree, index);
+ spin_unlock(&fs_info->reada_lock);
+ goto error;
+ }
+ }
+ spin_unlock(&fs_info->reada_lock);
+
+ return re;
+
+error:
+ while (nzones) {
+ struct reada_zone *zone;
+
+ --nzones;
+ zone = re->zones[nzones];
+ kref_get(&zone->refcnt);
+ spin_lock(&zone->lock);
+ --zone->elems;
+ if (zone->elems == 0) {
+ /*
+ * no fs_info->reada_lock needed, as this can't be
+ * the last ref
+ */
+ kref_put(&zone->refcnt, reada_zone_release);
+ }
+ spin_unlock(&zone->lock);
+
+ spin_lock(&fs_info->reada_lock);
+ kref_put(&zone->refcnt, reada_zone_release);
+ spin_unlock(&fs_info->reada_lock);
+ }
+ kfree(re);
+ if (looped)
+ goto again;
+ return NULL;
+}
+
+static void reada_kref_dummy(struct kref *kr)
+{
+}
+
+static void reada_extent_put(struct btrfs_fs_info *fs_info,
+ struct reada_extent *re)
+{
+ int i;
+ unsigned long index = re->logical >> PAGE_CACHE_SHIFT;
+
+ spin_lock(&fs_info->reada_lock);
+ if (!kref_put(&re->refcnt, reada_kref_dummy)) {
+ spin_unlock(&fs_info->reada_lock);
+ return;
+ }
+
+ radix_tree_delete(&fs_info->reada_tree, index);
+ for (i = 0; i < re->nzones; ++i) {
+ struct reada_zone *zone = re->zones[i];
+
+ radix_tree_delete(&zone->device->reada_extents, index);
+ }
+
+ spin_unlock(&fs_info->reada_lock);
+
+ for (i = 0; i < re->nzones; ++i) {
+ struct reada_zone *zone = re->zones[i];
+
+ kref_get(&zone->refcnt);
+ spin_lock(&zone->lock);
+ --zone->elems;
+ if (zone->elems == 0) {
+ /* no fs_info->reada_lock needed, as this can't be
+ * the last ref */
+ kref_put(&zone->refcnt, reada_zone_release);
+ }
+ spin_unlock(&zone->lock);
+
+ spin_lock(&fs_info->reada_lock);
+ kref_put(&zone->refcnt, reada_zone_release);
+ spin_unlock(&fs_info->reada_lock);
+ }
+ if (re->scheduled_for)
+ atomic_dec(&re->scheduled_for->reada_in_flight);
+
+ kfree(re);
+}
+
+static void reada_zone_release(struct kref *kref)
+{
+ struct reada_zone *zone = container_of(kref, struct reada_zone, refcnt);
+
+ radix_tree_delete(&zone->device->reada_zones,
+ zone->end >> PAGE_CACHE_SHIFT);
+
+ kfree(zone);
+}
+
+static void reada_control_release(struct kref *kref)
+{
+ struct reada_control *rc = container_of(kref, struct reada_control,
+ refcnt);
+
+ kfree(rc);
+}
+
+static int reada_add_block(struct reada_control *rc, u64 logical,
+ struct btrfs_key *top, int level, u64 generation)
+{
+ struct btrfs_root *root = rc->root;
+ struct reada_extent *re;
+ struct reada_extctl *rec;
+
+ re = reada_find_extent(root, logical, top, level); /* takes one ref */
+ if (!re)
+ return -1;
+
+ rec = kzalloc(sizeof(*rec), GFP_NOFS);
+ if (!rec) {
+ reada_extent_put(root->fs_info, re);
+ return -1;
+ }
+
+ rec->rc = rc;
+ rec->generation = generation;
+ atomic_inc(&rc->elems);
+
+ spin_lock(&re->lock);
+ list_add_tail(&rec->list, &re->extctl);
+ spin_unlock(&re->lock);
+
+ /* leave the ref on the extent */
+
+ return 0;
+}
+
+/*
+ * called with fs_info->reada_lock held
+ */
+static void reada_peer_zones_set_lock(struct reada_zone *zone, int lock)
+{
+ int i;
+ unsigned long index = zone->end >> PAGE_CACHE_SHIFT;
+
+ for (i = 0; i < zone->ndevs; ++i) {
+ struct reada_zone *peer;
+ peer = radix_tree_lookup(&zone->devs[i]->reada_zones, index);
+ if (peer && peer->device != zone->device)
+ peer->locked = lock;
+ }
+}
+
+/*
+ * called with fs_info->reada_lock held
+ */
+static int reada_pick_zone(struct btrfs_device *dev)
+{
+ struct reada_zone *top_zone = NULL;
+ struct reada_zone *top_locked_zone = NULL;
+ u64 top_elems = 0;
+ u64 top_locked_elems = 0;
+ unsigned long index = 0;
+ int ret;
+
+ if (dev->reada_curr_zone) {
+ reada_peer_zones_set_lock(dev->reada_curr_zone, 0);
+ kref_put(&dev->reada_curr_zone->refcnt, reada_zone_release);
+ dev->reada_curr_zone = NULL;
+ }
+ /* pick the zone with the most elements */
+ while (1) {
+ struct reada_zone *zone;
+
+ ret = radix_tree_gang_lookup(&dev->reada_zones,
+ (void **)&zone, index, 1);
+ if (ret == 0)
+ break;
+ index = (zone->end >> PAGE_CACHE_SHIFT) + 1;
+ if (zone->locked) {
+ if (zone->elems > top_locked_elems) {
+ top_locked_elems = zone->elems;
+ top_locked_zone = zone;
+ }
+ } else {
+ if (zone->elems > top_elems) {
+ top_elems = zone->elems;
+ top_zone = zone;
+ }
+ }
+ }
+ if (top_zone)
+ dev->reada_curr_zone = top_zone;
+ else if (top_locked_zone)
+ dev->reada_curr_zone = top_locked_zone;
+ else
+ return 0;
+
+ dev->reada_next = dev->reada_curr_zone->start;
+ kref_get(&dev->reada_curr_zone->refcnt);
+ reada_peer_zones_set_lock(dev->reada_curr_zone, 1);
+
+ return 1;
+}
+
+static int reada_start_machine_dev(struct btrfs_fs_info *fs_info,
+ struct btrfs_device *dev)
+{
+ struct reada_extent *re = NULL;
+ int mirror_num = 0;
+ struct extent_buffer *eb = NULL;
+ u64 logical;
+ u32 blocksize;
+ int ret;
+ int i;
+ int need_kick = 0;
+
+ spin_lock(&fs_info->reada_lock);
+ if (dev->reada_curr_zone == NULL) {
+ ret = reada_pick_zone(dev);
+ if (!ret) {
+ spin_unlock(&fs_info->reada_lock);
+ return 0;
+ }
+ }
+ /*
+ * FIXME currently we issue the reads one extent at a time. If we have
+ * a contiguous block of extents, we could also coagulate them or use
+ * plugging to speed things up
+ */
+ ret = radix_tree_gang_lookup(&dev->reada_extents, (void **)&re,
+ dev->reada_next >> PAGE_CACHE_SHIFT, 1);
+ if (ret == 0 || re->logical >= dev->reada_curr_zone->end) {
+ ret = reada_pick_zone(dev);
+ if (!ret) {
+ spin_unlock(&fs_info->reada_lock);
+ return 0;
+ }
+ re = NULL;
+ ret = radix_tree_gang_lookup(&dev->reada_extents, (void **)&re,
+ dev->reada_next >> PAGE_CACHE_SHIFT, 1);
+ }
+ if (ret == 0) {
+ spin_unlock(&fs_info->reada_lock);
+ return 0;
+ }
+ dev->reada_next = re->logical + re->blocksize;
+ kref_get(&re->refcnt);
+
+ spin_unlock(&fs_info->reada_lock);
+
+ /*
+ * find mirror num
+ */
+ for (i = 0; i < re->nzones; ++i) {
+ if (re->zones[i]->device == dev) {
+ mirror_num = i + 1;
+ break;
+ }
+ }
+ logical = re->logical;
+ blocksize = re->blocksize;
+
+ spin_lock(&re->lock);
+ if (re->scheduled_for == NULL) {
+ re->scheduled_for = dev;
+ need_kick = 1;
+ }
+ spin_unlock(&re->lock);
+
+ reada_extent_put(fs_info, re);
+
+ if (!need_kick)
+ return 0;
+
+ atomic_inc(&dev->reada_in_flight);
+ ret = reada_tree_block_flagged(fs_info->extent_root, logical, blocksize,
+ mirror_num, &eb);
+ if (ret)
+ __readahead_hook(fs_info->extent_root, NULL, logical, ret);
+ else if (eb)
+ __readahead_hook(fs_info->extent_root, eb, eb->start, ret);
+
+ if (eb)
+ free_extent_buffer(eb);
+
+ return 1;
+
+}
+
+static void reada_start_machine_worker(struct btrfs_work *work)
+{
+ struct reada_machine_work *rmw;
+ struct btrfs_fs_info *fs_info;
+
+ rmw = container_of(work, struct reada_machine_work, work);
+ fs_info = rmw->fs_info;
+
+ kfree(rmw);
+
+ __reada_start_machine(fs_info);
+}
+
+static void __reada_start_machine(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_device *device;
+ struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
+ u64 enqueued;
+ u64 total = 0;
+ int i;
+
+ do {
+ enqueued = 0;
+ list_for_each_entry(device, &fs_devices->devices, dev_list) {
+ if (atomic_read(&device->reada_in_flight) <
+ MAX_IN_FLIGHT)
+ enqueued += reada_start_machine_dev(fs_info,
+ device);
+ }
+ total += enqueued;
+ } while (enqueued && total < 10000);
+
+ if (enqueued == 0)
+ return;
+
+ /*
+ * If everything is already in the cache, this is effectively single
+ * threaded. To a) not hold the caller for too long and b) to utilize
+ * more cores, we broke the loop above after 10000 iterations and now
+ * enqueue to workers to finish it. This will distribute the load to
+ * the cores.
+ */
+ for (i = 0; i < 2; ++i)
+ reada_start_machine(fs_info);
+}
+
+static void reada_start_machine(struct btrfs_fs_info *fs_info)
+{
+ struct reada_machine_work *rmw;
+
+ rmw = kzalloc(sizeof(*rmw), GFP_NOFS);
+ if (!rmw) {
+ /* FIXME we cannot handle this properly right now */
+ BUG();
+ }
+ rmw->work.func = reada_start_machine_worker;
+ rmw->fs_info = fs_info;
+
+ btrfs_queue_worker(&fs_info->readahead_workers, &rmw->work);
+}
+
+#ifdef DEBUG
+static void dump_devs(struct btrfs_fs_info *fs_info, int all)
+{
+ struct btrfs_device *device;
+ struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
+ unsigned long index;
+ int ret;
+ int i;
+ int j;
+ int cnt;
+
+ spin_lock(&fs_info->reada_lock);
+ list_for_each_entry(device, &fs_devices->devices, dev_list) {
+ printk(KERN_DEBUG "dev %lld has %d in flight\n", device->devid,
+ atomic_read(&device->reada_in_flight));
+ index = 0;
+ while (1) {
+ struct reada_zone *zone;
+ ret = radix_tree_gang_lookup(&device->reada_zones,
+ (void **)&zone, index, 1);
+ if (ret == 0)
+ break;
+ printk(KERN_DEBUG " zone %llu-%llu elems %llu locked "
+ "%d devs", zone->start, zone->end, zone->elems,
+ zone->locked);
+ for (j = 0; j < zone->ndevs; ++j) {
+ printk(KERN_CONT " %lld",
+ zone->devs[j]->devid);
+ }
+ if (device->reada_curr_zone == zone)
+ printk(KERN_CONT " curr off %llu",
+ device->reada_next - zone->start);
+ printk(KERN_CONT "\n");
+ index = (zone->end >> PAGE_CACHE_SHIFT) + 1;
+ }
+ cnt = 0;
+ index = 0;
+ while (all) {
+ struct reada_extent *re = NULL;
+
+ ret = radix_tree_gang_lookup(&device->reada_extents,
+ (void **)&re, index, 1);
+ if (ret == 0)
+ break;
+ printk(KERN_DEBUG
+ " re: logical %llu size %u empty %d for %lld",
+ re->logical, re->blocksize,
+ list_empty(&re->extctl), re->scheduled_for ?
+ re->scheduled_for->devid : -1);
+
+ for (i = 0; i < re->nzones; ++i) {
+ printk(KERN_CONT " zone %llu-%llu devs",
+ re->zones[i]->start,
+ re->zones[i]->end);
+ for (j = 0; j < re->zones[i]->ndevs; ++j) {
+ printk(KERN_CONT " %lld",
+ re->zones[i]->devs[j]->devid);
+ }
+ }
+ printk(KERN_CONT "\n");
+ index = (re->logical >> PAGE_CACHE_SHIFT) + 1;
+ if (++cnt > 15)
+ break;
+ }
+ }
+
+ index = 0;
+ cnt = 0;
+ while (all) {
+ struct reada_extent *re = NULL;
+
+ ret = radix_tree_gang_lookup(&fs_info->reada_tree, (void **)&re,
+ index, 1);
+ if (ret == 0)
+ break;
+ if (!re->scheduled_for) {
+ index = (re->logical >> PAGE_CACHE_SHIFT) + 1;
+ continue;
+ }
+ printk(KERN_DEBUG
+ "re: logical %llu size %u list empty %d for %lld",
+ re->logical, re->blocksize, list_empty(&re->extctl),
+ re->scheduled_for ? re->scheduled_for->devid : -1);
+ for (i = 0; i < re->nzones; ++i) {
+ printk(KERN_CONT " zone %llu-%llu devs",
+ re->zones[i]->start,
+ re->zones[i]->end);
+ for (i = 0; i < re->nzones; ++i) {
+ printk(KERN_CONT " zone %llu-%llu devs",
+ re->zones[i]->start,
+ re->zones[i]->end);
+ for (j = 0; j < re->zones[i]->ndevs; ++j) {
+ printk(KERN_CONT " %lld",
+ re->zones[i]->devs[j]->devid);
+ }
+ }
+ }
+ printk(KERN_CONT "\n");
+ index = (re->logical >> PAGE_CACHE_SHIFT) + 1;
+ }
+ spin_unlock(&fs_info->reada_lock);
+}
+#endif
+
+/*
+ * interface
+ */
+struct reada_control *btrfs_reada_add(struct btrfs_root *root,
+ struct btrfs_key *key_start, struct btrfs_key *key_end)
+{
+ struct reada_control *rc;
+ u64 start;
+ u64 generation;
+ int level;
+ struct extent_buffer *node;
+ static struct btrfs_key max_key = {
+ .objectid = (u64)-1,
+ .type = (u8)-1,
+ .offset = (u64)-1
+ };
+
+ rc = kzalloc(sizeof(*rc), GFP_NOFS);
+ if (!rc)
+ return ERR_PTR(-ENOMEM);
+
+ rc->root = root;
+ rc->key_start = *key_start;
+ rc->key_end = *key_end;
+ atomic_set(&rc->elems, 0);
+ init_waitqueue_head(&rc->wait);
+ kref_init(&rc->refcnt);
+ kref_get(&rc->refcnt); /* one ref for having elements */
+
+ node = btrfs_root_node(root);
+ start = node->start;
+ level = btrfs_header_level(node);
+ generation = btrfs_header_generation(node);
+ free_extent_buffer(node);
+
+ reada_add_block(rc, start, &max_key, level, generation);
+
+ reada_start_machine(root->fs_info);
+
+ return rc;
+}
+
+#ifdef DEBUG
+int btrfs_reada_wait(void *handle)
+{
+ struct reada_control *rc = handle;
+
+ while (atomic_read(&rc->elems)) {
+ wait_event_timeout(rc->wait, atomic_read(&rc->elems) == 0,
+ 5 * HZ);
+ dump_devs(rc->root->fs_info, rc->elems < 10 ? 1 : 0);
+ }
+
+ dump_devs(rc->root->fs_info, rc->elems < 10 ? 1 : 0);
+
+ kref_put(&rc->refcnt, reada_control_release);
+
+ return 0;
+}
+#else
+int btrfs_reada_wait(void *handle)
+{
+ struct reada_control *rc = handle;
+
+ while (atomic_read(&rc->elems)) {
+ wait_event(rc->wait, atomic_read(&rc->elems) == 0);
+ }
+
+ kref_put(&rc->refcnt, reada_control_release);
+
+ return 0;
+}
+#endif
+
+void btrfs_reada_detach(void *handle)
+{
+ struct reada_control *rc = handle;
+
+ kref_put(&rc->refcnt, reada_control_release);
+}
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index 69a600f07763..5bc4ec827b3d 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -29,15 +29,12 @@
* any can be found.
*
* Future enhancements:
- * - To enhance the performance, better read-ahead strategies for the
- * extent-tree can be employed.
* - In case an unrepairable extent is encountered, track which files are
* affected and report them
* - In case of a read error on files with nodatasum, map the file and read
* the extent to trigger a writeback of the good copy
* - track and record media errors, throw out bad devices
* - add a mode to also read unallocated space
- * - make the prefetch cancellable
*/
struct scrub_bio;
@@ -741,13 +738,16 @@ static noinline_for_stack int scrub_stripe(struct scrub_dev *sdev,
int slot;
int i;
u64 nstripes;
- int start_stripe;
struct extent_buffer *l;
struct btrfs_key key;
u64 physical;
u64 logical;
u64 generation;
u64 mirror_num;
+ struct reada_control *reada1;
+ struct reada_control *reada2;
+ struct btrfs_key key_start;
+ struct btrfs_key key_end;
u64 increment = map->stripe_len;
u64 offset;
@@ -779,81 +779,67 @@ static noinline_for_stack int scrub_stripe(struct scrub_dev *sdev,
if (!path)
return -ENOMEM;
- path->reada = 2;
path->search_commit_root = 1;
path->skip_locking = 1;
/*
- * find all extents for each stripe and just read them to get
- * them into the page cache
- * FIXME: we can do better. build a more intelligent prefetching
+ * trigger the readahead for extent tree csum tree and wait for
+ * completion. During readahead, the scrub is officially paused
+ * to not hold off transaction commits
*/
logical = base + offset;
- physical = map->stripes[num].physical;
- ret = 0;
- for (i = 0; i < nstripes; ++i) {
- key.objectid = logical;
- key.type = BTRFS_EXTENT_ITEM_KEY;
- key.offset = (u64)0;
-
- ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
- if (ret < 0)
- goto out_noplug;
-
- /*
- * we might miss half an extent here, but that doesn't matter,
- * as it's only the prefetch
- */
- while (1) {
- l = path->nodes[0];
- slot = path->slots[0];
- if (slot >= btrfs_header_nritems(l)) {
- ret = btrfs_next_leaf(root, path);
- if (ret == 0)
- continue;
- if (ret < 0)
- goto out_noplug;
- break;
- }
- btrfs_item_key_to_cpu(l, &key, slot);
+ wait_event(sdev->list_wait,
+ atomic_read(&sdev->in_flight) == 0);
+ atomic_inc(&fs_info->scrubs_paused);
+ wake_up(&fs_info->scrub_pause_wait);
- if (key.objectid >= logical + map->stripe_len)
- break;
+ /* FIXME it might be better to start readahead at commit root */
+ key_start.objectid = logical;
+ key_start.type = BTRFS_EXTENT_ITEM_KEY;
+ key_start.offset = (u64)0;
+ key_end.objectid = base + offset + nstripes * increment;
+ key_end.type = BTRFS_EXTENT_ITEM_KEY;
+ key_end.offset = (u64)0;
+ reada1 = btrfs_reada_add(root, &key_start, &key_end);
+
+ key_start.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
+ key_start.type = BTRFS_EXTENT_CSUM_KEY;
+ key_start.offset = logical;
+ key_end.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
+ key_end.type = BTRFS_EXTENT_CSUM_KEY;
+ key_end.offset = base + offset + nstripes * increment;
+ reada2 = btrfs_reada_add(csum_root, &key_start, &key_end);
+
+ if (!IS_ERR(reada1))
+ btrfs_reada_wait(reada1);
+ if (!IS_ERR(reada2))
+ btrfs_reada_wait(reada2);
- path->slots[0]++;
- }
- btrfs_release_path(path);
- logical += increment;
- physical += map->stripe_len;
- cond_resched();
+ mutex_lock(&fs_info->scrub_lock);
+ while (atomic_read(&fs_info->scrub_pause_req)) {
+ mutex_unlock(&fs_info->scrub_lock);
+ wait_event(fs_info->scrub_pause_wait,
+ atomic_read(&fs_info->scrub_pause_req) == 0);
+ mutex_lock(&fs_info->scrub_lock);
}
+ atomic_dec(&fs_info->scrubs_paused);
+ mutex_unlock(&fs_info->scrub_lock);
+ wake_up(&fs_info->scrub_pause_wait);
/*
* collect all data csums for the stripe to avoid seeking during
* the scrub. This might currently (crc32) end up to be about 1MB
*/
- start_stripe = 0;
blk_start_plug(&plug);
-again:
- logical = base + offset + start_stripe * increment;
- for (i = start_stripe; i < nstripes; ++i) {
- ret = btrfs_lookup_csums_range(csum_root, logical,
- logical + map->stripe_len - 1,
- &sdev->csum_list, 1);
- if (ret)
- goto out;
- logical += increment;
- cond_resched();
- }
/*
* now find all extents for each stripe and scrub them
*/
- logical = base + offset + start_stripe * increment;
- physical = map->stripes[num].physical + start_stripe * map->stripe_len;
+ logical = base + offset;
+ physical = map->stripes[num].physical;
ret = 0;
- for (i = start_stripe; i < nstripes; ++i) {
+ for (i = 0; i < nstripes; ++i) {
/*
* canceled?
*/
@@ -882,11 +868,14 @@ again:
atomic_dec(&fs_info->scrubs_paused);
mutex_unlock(&fs_info->scrub_lock);
wake_up(&fs_info->scrub_pause_wait);
- scrub_free_csums(sdev);
- start_stripe = i;
- goto again;
}
+ ret = btrfs_lookup_csums_range(csum_root, logical,
+ logical + map->stripe_len - 1,
+ &sdev->csum_list, 1);
+ if (ret)
+ goto out;
+
key.objectid = logical;
key.type = BTRFS_EXTENT_ITEM_KEY;
key.offset = (u64)0;
@@ -982,7 +971,6 @@ next:
out:
blk_finish_plug(&plug);
-out_noplug:
btrfs_free_path(path);
return ret < 0 ? ret : 0;
}
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index c3b45564048e..f1685a2b45c8 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -366,6 +366,14 @@ static noinline int device_list_add(const char *path,
}
INIT_LIST_HEAD(&device->dev_alloc_list);
+ /* init readahead state */
+ spin_lock_init(&device->reada_lock);
+ device->reada_curr_zone = NULL;
+ atomic_set(&device->reada_in_flight, 0);
+ device->reada_next = 0;
+ INIT_RADIX_TREE(&device->reada_zones, GFP_NOFS & ~__GFP_WAIT);
+ INIT_RADIX_TREE(&device->reada_extents, GFP_NOFS & ~__GFP_WAIT);
+
mutex_lock(&fs_devices->device_list_mutex);
list_add_rcu(&device->dev_list, &fs_devices->devices);
mutex_unlock(&fs_devices->device_list_mutex);
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 6d866db4e177..2a751246188a 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -92,6 +92,14 @@ struct btrfs_device {
struct btrfs_work work;
struct rcu_head rcu;
struct work_struct rcu_work;
+
+ /* readahead state */
+ spinlock_t reada_lock;
+ atomic_t reada_in_flight;
+ u64 reada_next;
+ struct reada_zone *reada_curr_zone;
+ struct radix_tree_root reada_zones;
+ struct radix_tree_root reada_extents;
};
struct btrfs_fs_devices {