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-rw-r--r--fs/btrfs/btrfs_inode.h1
-rw-r--r--fs/btrfs/check-integrity.c16
-rw-r--r--fs/btrfs/disk-io.c57
-rw-r--r--fs/btrfs/extent_io.c7
-rw-r--r--fs/btrfs/inode.c64
-rw-r--r--fs/btrfs/ioctl.c110
-rw-r--r--fs/btrfs/ordered-data.c22
-rw-r--r--fs/btrfs/rcu-string.h56
-rw-r--r--fs/btrfs/scrub.c30
-rw-r--r--fs/btrfs/super.c33
-rw-r--r--fs/btrfs/transaction.c14
-rw-r--r--fs/btrfs/volumes.c92
-rw-r--r--fs/btrfs/volumes.h2
13 files changed, 353 insertions, 151 deletions
diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h
index e616f8872e69..12394a90d60f 100644
--- a/fs/btrfs/btrfs_inode.h
+++ b/fs/btrfs/btrfs_inode.h
@@ -37,6 +37,7 @@
#define BTRFS_INODE_IN_DEFRAG 3
#define BTRFS_INODE_DELALLOC_META_RESERVED 4
#define BTRFS_INODE_HAS_ORPHAN_ITEM 5
+#define BTRFS_INODE_HAS_ASYNC_EXTENT 6
/* in memory btrfs inode */
struct btrfs_inode {
diff --git a/fs/btrfs/check-integrity.c b/fs/btrfs/check-integrity.c
index 9cebb1fd6a3c..da6e9364a5e3 100644
--- a/fs/btrfs/check-integrity.c
+++ b/fs/btrfs/check-integrity.c
@@ -93,6 +93,7 @@
#include "print-tree.h"
#include "locking.h"
#include "check-integrity.h"
+#include "rcu-string.h"
#define BTRFSIC_BLOCK_HASHTABLE_SIZE 0x10000
#define BTRFSIC_BLOCK_LINK_HASHTABLE_SIZE 0x10000
@@ -843,13 +844,14 @@ static int btrfsic_process_superblock_dev_mirror(
superblock_tmp->never_written = 0;
superblock_tmp->mirror_num = 1 + superblock_mirror_num;
if (state->print_mask & BTRFSIC_PRINT_MASK_SUPERBLOCK_WRITE)
- printk(KERN_INFO "New initial S-block (bdev %p, %s)"
- " @%llu (%s/%llu/%d)\n",
- superblock_bdev, device->name,
- (unsigned long long)dev_bytenr,
- dev_state->name,
- (unsigned long long)dev_bytenr,
- superblock_mirror_num);
+ printk_in_rcu(KERN_INFO "New initial S-block (bdev %p, %s)"
+ " @%llu (%s/%llu/%d)\n",
+ superblock_bdev,
+ rcu_str_deref(device->name),
+ (unsigned long long)dev_bytenr,
+ dev_state->name,
+ (unsigned long long)dev_bytenr,
+ superblock_mirror_num);
list_add(&superblock_tmp->all_blocks_node,
&state->all_blocks_list);
btrfsic_block_hashtable_add(superblock_tmp,
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index b99d5127ba18..9a569aef72ea 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -44,6 +44,7 @@
#include "free-space-cache.h"
#include "inode-map.h"
#include "check-integrity.h"
+#include "rcu-string.h"
static struct extent_io_ops btree_extent_io_ops;
static void end_workqueue_fn(struct btrfs_work *work);
@@ -2118,7 +2119,7 @@ int open_ctree(struct super_block *sb,
features = btrfs_super_incompat_flags(disk_super);
features |= BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF;
- if (tree_root->fs_info->compress_type & BTRFS_COMPRESS_LZO)
+ if (tree_root->fs_info->compress_type == BTRFS_COMPRESS_LZO)
features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
/*
@@ -2575,8 +2576,9 @@ static void btrfs_end_buffer_write_sync(struct buffer_head *bh, int uptodate)
struct btrfs_device *device = (struct btrfs_device *)
bh->b_private;
- printk_ratelimited(KERN_WARNING "lost page write due to "
- "I/O error on %s\n", device->name);
+ printk_ratelimited_in_rcu(KERN_WARNING "lost page write due to "
+ "I/O error on %s\n",
+ rcu_str_deref(device->name));
/* note, we dont' set_buffer_write_io_error because we have
* our own ways of dealing with the IO errors
*/
@@ -2749,8 +2751,8 @@ static int write_dev_flush(struct btrfs_device *device, int wait)
wait_for_completion(&device->flush_wait);
if (bio_flagged(bio, BIO_EOPNOTSUPP)) {
- printk("btrfs: disabling barriers on dev %s\n",
- device->name);
+ printk_in_rcu("btrfs: disabling barriers on dev %s\n",
+ rcu_str_deref(device->name));
device->nobarriers = 1;
}
if (!bio_flagged(bio, BIO_UPTODATE)) {
@@ -3400,7 +3402,6 @@ int btrfs_destroy_delayed_refs(struct btrfs_transaction *trans,
delayed_refs = &trans->delayed_refs;
-again:
spin_lock(&delayed_refs->lock);
if (delayed_refs->num_entries == 0) {
spin_unlock(&delayed_refs->lock);
@@ -3408,31 +3409,36 @@ again:
return ret;
}
- node = rb_first(&delayed_refs->root);
- while (node) {
+ while ((node = rb_first(&delayed_refs->root)) != NULL) {
ref = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
- node = rb_next(node);
-
- ref->in_tree = 0;
- rb_erase(&ref->rb_node, &delayed_refs->root);
- delayed_refs->num_entries--;
atomic_set(&ref->refs, 1);
if (btrfs_delayed_ref_is_head(ref)) {
struct btrfs_delayed_ref_head *head;
head = btrfs_delayed_node_to_head(ref);
- spin_unlock(&delayed_refs->lock);
- mutex_lock(&head->mutex);
+ if (!mutex_trylock(&head->mutex)) {
+ atomic_inc(&ref->refs);
+ spin_unlock(&delayed_refs->lock);
+
+ /* Need to wait for the delayed ref to run */
+ mutex_lock(&head->mutex);
+ mutex_unlock(&head->mutex);
+ btrfs_put_delayed_ref(ref);
+
+ continue;
+ }
+
kfree(head->extent_op);
delayed_refs->num_heads--;
if (list_empty(&head->cluster))
delayed_refs->num_heads_ready--;
list_del_init(&head->cluster);
- mutex_unlock(&head->mutex);
- btrfs_put_delayed_ref(ref);
- goto again;
}
+ ref->in_tree = 0;
+ rb_erase(&ref->rb_node, &delayed_refs->root);
+ delayed_refs->num_entries--;
+
spin_unlock(&delayed_refs->lock);
btrfs_put_delayed_ref(ref);
@@ -3520,11 +3526,9 @@ static int btrfs_destroy_marked_extents(struct btrfs_root *root,
&(&BTRFS_I(page->mapping->host)->io_tree)->buffer,
offset >> PAGE_CACHE_SHIFT);
spin_unlock(&dirty_pages->buffer_lock);
- if (eb) {
+ if (eb)
ret = test_and_clear_bit(EXTENT_BUFFER_DIRTY,
&eb->bflags);
- atomic_set(&eb->refs, 1);
- }
if (PageWriteback(page))
end_page_writeback(page);
@@ -3538,8 +3542,8 @@ static int btrfs_destroy_marked_extents(struct btrfs_root *root,
spin_unlock_irq(&page->mapping->tree_lock);
}
- page->mapping->a_ops->invalidatepage(page, 0);
unlock_page(page);
+ page_cache_release(page);
}
}
@@ -3585,16 +3589,13 @@ void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans,
/* FIXME: cleanup wait for commit */
cur_trans->in_commit = 1;
cur_trans->blocked = 1;
- if (waitqueue_active(&root->fs_info->transaction_blocked_wait))
- wake_up(&root->fs_info->transaction_blocked_wait);
+ wake_up(&root->fs_info->transaction_blocked_wait);
cur_trans->blocked = 0;
- if (waitqueue_active(&root->fs_info->transaction_wait))
- wake_up(&root->fs_info->transaction_wait);
+ wake_up(&root->fs_info->transaction_wait);
cur_trans->commit_done = 1;
- if (waitqueue_active(&cur_trans->commit_wait))
- wake_up(&cur_trans->commit_wait);
+ wake_up(&cur_trans->commit_wait);
btrfs_destroy_pending_snapshots(cur_trans);
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 2c8f7b204617..aaa12c1eb348 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -20,6 +20,7 @@
#include "volumes.h"
#include "check-integrity.h"
#include "locking.h"
+#include "rcu-string.h"
static struct kmem_cache *extent_state_cache;
static struct kmem_cache *extent_buffer_cache;
@@ -1917,9 +1918,9 @@ int repair_io_failure(struct btrfs_mapping_tree *map_tree, u64 start,
return -EIO;
}
- printk(KERN_INFO "btrfs read error corrected: ino %lu off %llu (dev %s "
- "sector %llu)\n", page->mapping->host->i_ino, start,
- dev->name, sector);
+ printk_in_rcu(KERN_INFO "btrfs read error corrected: ino %lu off %llu "
+ "(dev %s sector %llu)\n", page->mapping->host->i_ino,
+ start, rcu_str_deref(dev->name), sector);
bio_put(bio);
return 0;
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 92df0a5d1d94..7a090fb4eb98 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -830,7 +830,7 @@ static noinline int cow_file_range(struct inode *inode,
if (IS_ERR(trans)) {
extent_clear_unlock_delalloc(inode,
&BTRFS_I(inode)->io_tree,
- start, end, NULL,
+ start, end, locked_page,
EXTENT_CLEAR_UNLOCK_PAGE |
EXTENT_CLEAR_UNLOCK |
EXTENT_CLEAR_DELALLOC |
@@ -963,7 +963,7 @@ out:
out_unlock:
extent_clear_unlock_delalloc(inode,
&BTRFS_I(inode)->io_tree,
- start, end, NULL,
+ start, end, locked_page,
EXTENT_CLEAR_UNLOCK_PAGE |
EXTENT_CLEAR_UNLOCK |
EXTENT_CLEAR_DELALLOC |
@@ -986,8 +986,10 @@ static noinline void async_cow_start(struct btrfs_work *work)
compress_file_range(async_cow->inode, async_cow->locked_page,
async_cow->start, async_cow->end, async_cow,
&num_added);
- if (num_added == 0)
+ if (num_added == 0) {
+ iput(async_cow->inode);
async_cow->inode = NULL;
+ }
}
/*
@@ -1020,6 +1022,8 @@ static noinline void async_cow_free(struct btrfs_work *work)
{
struct async_cow *async_cow;
async_cow = container_of(work, struct async_cow, work);
+ if (async_cow->inode)
+ iput(async_cow->inode);
kfree(async_cow);
}
@@ -1038,7 +1042,7 @@ static int cow_file_range_async(struct inode *inode, struct page *locked_page,
while (start < end) {
async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS);
BUG_ON(!async_cow); /* -ENOMEM */
- async_cow->inode = inode;
+ async_cow->inode = igrab(inode);
async_cow->root = root;
async_cow->locked_page = locked_page;
async_cow->start = start;
@@ -1136,8 +1140,18 @@ static noinline int run_delalloc_nocow(struct inode *inode,
u64 ino = btrfs_ino(inode);
path = btrfs_alloc_path();
- if (!path)
+ if (!path) {
+ extent_clear_unlock_delalloc(inode,
+ &BTRFS_I(inode)->io_tree,
+ start, end, locked_page,
+ EXTENT_CLEAR_UNLOCK_PAGE |
+ EXTENT_CLEAR_UNLOCK |
+ EXTENT_CLEAR_DELALLOC |
+ EXTENT_CLEAR_DIRTY |
+ EXTENT_SET_WRITEBACK |
+ EXTENT_END_WRITEBACK);
return -ENOMEM;
+ }
nolock = btrfs_is_free_space_inode(root, inode);
@@ -1147,6 +1161,15 @@ static noinline int run_delalloc_nocow(struct inode *inode,
trans = btrfs_join_transaction(root);
if (IS_ERR(trans)) {
+ extent_clear_unlock_delalloc(inode,
+ &BTRFS_I(inode)->io_tree,
+ start, end, locked_page,
+ EXTENT_CLEAR_UNLOCK_PAGE |
+ EXTENT_CLEAR_UNLOCK |
+ EXTENT_CLEAR_DELALLOC |
+ EXTENT_CLEAR_DIRTY |
+ EXTENT_SET_WRITEBACK |
+ EXTENT_END_WRITEBACK);
btrfs_free_path(path);
return PTR_ERR(trans);
}
@@ -1327,8 +1350,11 @@ out_check:
}
btrfs_release_path(path);
- if (cur_offset <= end && cow_start == (u64)-1)
+ if (cur_offset <= end && cow_start == (u64)-1) {
cow_start = cur_offset;
+ cur_offset = end;
+ }
+
if (cow_start != (u64)-1) {
ret = cow_file_range(inode, locked_page, cow_start, end,
page_started, nr_written, 1);
@@ -1347,6 +1373,17 @@ error:
if (!ret)
ret = err;
+ if (ret && cur_offset < end)
+ extent_clear_unlock_delalloc(inode,
+ &BTRFS_I(inode)->io_tree,
+ cur_offset, end, locked_page,
+ EXTENT_CLEAR_UNLOCK_PAGE |
+ EXTENT_CLEAR_UNLOCK |
+ EXTENT_CLEAR_DELALLOC |
+ EXTENT_CLEAR_DIRTY |
+ EXTENT_SET_WRITEBACK |
+ EXTENT_END_WRITEBACK);
+
btrfs_free_path(path);
return ret;
}
@@ -1361,20 +1398,23 @@ static int run_delalloc_range(struct inode *inode, struct page *locked_page,
int ret;
struct btrfs_root *root = BTRFS_I(inode)->root;
- if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW)
+ if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) {
ret = run_delalloc_nocow(inode, locked_page, start, end,
page_started, 1, nr_written);
- else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC)
+ } else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC) {
ret = run_delalloc_nocow(inode, locked_page, start, end,
page_started, 0, nr_written);
- else if (!btrfs_test_opt(root, COMPRESS) &&
- !(BTRFS_I(inode)->force_compress) &&
- !(BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS))
+ } else if (!btrfs_test_opt(root, COMPRESS) &&
+ !(BTRFS_I(inode)->force_compress) &&
+ !(BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS)) {
ret = cow_file_range(inode, locked_page, start, end,
page_started, nr_written, 1);
- else
+ } else {
+ set_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
+ &BTRFS_I(inode)->runtime_flags);
ret = cow_file_range_async(inode, locked_page, start, end,
page_started, nr_written);
+ }
return ret;
}
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 24b776c08d99..a98f7d252829 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -52,6 +52,7 @@
#include "locking.h"
#include "inode-map.h"
#include "backref.h"
+#include "rcu-string.h"
/* Mask out flags that are inappropriate for the given type of inode. */
static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
@@ -785,39 +786,57 @@ none:
return -ENOENT;
}
-/*
- * Validaty check of prev em and next em:
- * 1) no prev/next em
- * 2) prev/next em is an hole/inline extent
- */
-static int check_adjacent_extents(struct inode *inode, struct extent_map *em)
+static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
{
struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
- struct extent_map *prev = NULL, *next = NULL;
- int ret = 0;
+ struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
+ struct extent_map *em;
+ u64 len = PAGE_CACHE_SIZE;
+ /*
+ * hopefully we have this extent in the tree already, try without
+ * the full extent lock
+ */
read_lock(&em_tree->lock);
- prev = lookup_extent_mapping(em_tree, em->start - 1, (u64)-1);
- next = lookup_extent_mapping(em_tree, em->start + em->len, (u64)-1);
+ em = lookup_extent_mapping(em_tree, start, len);
read_unlock(&em_tree->lock);
- if ((!prev || prev->block_start >= EXTENT_MAP_LAST_BYTE) &&
- (!next || next->block_start >= EXTENT_MAP_LAST_BYTE))
- ret = 1;
- free_extent_map(prev);
- free_extent_map(next);
+ if (!em) {
+ /* get the big lock and read metadata off disk */
+ lock_extent(io_tree, start, start + len - 1);
+ em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
+ unlock_extent(io_tree, start, start + len - 1);
+
+ if (IS_ERR(em))
+ return NULL;
+ }
+
+ return em;
+}
+static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
+{
+ struct extent_map *next;
+ bool ret = true;
+
+ /* this is the last extent */
+ if (em->start + em->len >= i_size_read(inode))
+ return false;
+
+ next = defrag_lookup_extent(inode, em->start + em->len);
+ if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
+ ret = false;
+
+ free_extent_map(next);
return ret;
}
-static int should_defrag_range(struct inode *inode, u64 start, u64 len,
- int thresh, u64 *last_len, u64 *skip,
- u64 *defrag_end)
+static int should_defrag_range(struct inode *inode, u64 start, int thresh,
+ u64 *last_len, u64 *skip, u64 *defrag_end)
{
- struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
- struct extent_map *em = NULL;
- struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
+ struct extent_map *em;
int ret = 1;
+ bool next_mergeable = true;
/*
* make sure that once we start defragging an extent, we keep on
@@ -828,23 +847,9 @@ static int should_defrag_range(struct inode *inode, u64 start, u64 len,
*skip = 0;
- /*
- * hopefully we have this extent in the tree already, try without
- * the full extent lock
- */
- read_lock(&em_tree->lock);
- em = lookup_extent_mapping(em_tree, start, len);
- read_unlock(&em_tree->lock);
-
- if (!em) {
- /* get the big lock and read metadata off disk */
- lock_extent(io_tree, start, start + len - 1);
- em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
- unlock_extent(io_tree, start, start + len - 1);
-
- if (IS_ERR(em))
- return 0;
- }
+ em = defrag_lookup_extent(inode, start);
+ if (!em)
+ return 0;
/* this will cover holes, and inline extents */
if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
@@ -852,18 +857,15 @@ static int should_defrag_range(struct inode *inode, u64 start, u64 len,
goto out;
}
- /* If we have nothing to merge with us, just skip. */
- if (check_adjacent_extents(inode, em)) {
- ret = 0;
- goto out;
- }
+ next_mergeable = defrag_check_next_extent(inode, em);
/*
- * we hit a real extent, if it is big don't bother defragging it again
+ * we hit a real extent, if it is big or the next extent is not a
+ * real extent, don't bother defragging it
*/
- if ((*last_len == 0 || *last_len >= thresh) && em->len >= thresh)
+ if ((*last_len == 0 || *last_len >= thresh) &&
+ (em->len >= thresh || !next_mergeable))
ret = 0;
-
out:
/*
* last_len ends up being a counter of how many bytes we've defragged.
@@ -1142,8 +1144,8 @@ int btrfs_defrag_file(struct inode *inode, struct file *file,
break;
if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
- PAGE_CACHE_SIZE, extent_thresh,
- &last_len, &skip, &defrag_end)) {
+ extent_thresh, &last_len, &skip,
+ &defrag_end)) {
unsigned long next;
/*
* the should_defrag function tells us how much to skip
@@ -1345,8 +1347,9 @@ static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
do_div(new_size, root->sectorsize);
new_size *= root->sectorsize;
- printk(KERN_INFO "btrfs: new size for %s is %llu\n",
- device->name, (unsigned long long)new_size);
+ printk_in_rcu(KERN_INFO "btrfs: new size for %s is %llu\n",
+ rcu_str_deref(device->name),
+ (unsigned long long)new_size);
if (new_size > old_size) {
trans = btrfs_start_transaction(root, 0);
@@ -2264,7 +2267,12 @@ static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
di_args->total_bytes = dev->total_bytes;
memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
if (dev->name) {
- strncpy(di_args->path, dev->name, sizeof(di_args->path));
+ struct rcu_string *name;
+
+ rcu_read_lock();
+ name = rcu_dereference(dev->name);
+ strncpy(di_args->path, name->str, sizeof(di_args->path));
+ rcu_read_unlock();
di_args->path[sizeof(di_args->path) - 1] = 0;
} else {
di_args->path[0] = '\0';
diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c
index 9e138cdc36c5..643335a4fe3c 100644
--- a/fs/btrfs/ordered-data.c
+++ b/fs/btrfs/ordered-data.c
@@ -627,7 +627,27 @@ void btrfs_wait_ordered_range(struct inode *inode, u64 start, u64 len)
/* start IO across the range first to instantiate any delalloc
* extents
*/
- filemap_write_and_wait_range(inode->i_mapping, start, orig_end);
+ filemap_fdatawrite_range(inode->i_mapping, start, orig_end);
+
+ /*
+ * So with compression we will find and lock a dirty page and clear the
+ * first one as dirty, setup an async extent, and immediately return
+ * with the entire range locked but with nobody actually marked with
+ * writeback. So we can't just filemap_write_and_wait_range() and
+ * expect it to work since it will just kick off a thread to do the
+ * actual work. So we need to call filemap_fdatawrite_range _again_
+ * since it will wait on the page lock, which won't be unlocked until
+ * after the pages have been marked as writeback and so we're good to go
+ * from there. We have to do this otherwise we'll miss the ordered
+ * extents and that results in badness. Please Josef, do not think you
+ * know better and pull this out at some point in the future, it is
+ * right and you are wrong.
+ */
+ if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
+ &BTRFS_I(inode)->runtime_flags))
+ filemap_fdatawrite_range(inode->i_mapping, start, orig_end);
+
+ filemap_fdatawait_range(inode->i_mapping, start, orig_end);
end = orig_end;
found = 0;
diff --git a/fs/btrfs/rcu-string.h b/fs/btrfs/rcu-string.h
new file mode 100644
index 000000000000..9e111e4576d4
--- /dev/null
+++ b/fs/btrfs/rcu-string.h
@@ -0,0 +1,56 @@
+/*
+ * Copyright (C) 2012 Red Hat. 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.
+ */
+
+struct rcu_string {
+ struct rcu_head rcu;
+ char str[0];
+};
+
+static inline struct rcu_string *rcu_string_strdup(const char *src, gfp_t mask)
+{
+ size_t len = strlen(src) + 1;
+ struct rcu_string *ret = kzalloc(sizeof(struct rcu_string) +
+ (len * sizeof(char)), mask);
+ if (!ret)
+ return ret;
+ strncpy(ret->str, src, len);
+ return ret;
+}
+
+static inline void rcu_string_free(struct rcu_string *str)
+{
+ if (str)
+ kfree_rcu(str, rcu);
+}
+
+#define printk_in_rcu(fmt, ...) do { \
+ rcu_read_lock(); \
+ printk(fmt, __VA_ARGS__); \
+ rcu_read_unlock(); \
+} while (0)
+
+#define printk_ratelimited_in_rcu(fmt, ...) do { \
+ rcu_read_lock(); \
+ printk_ratelimited(fmt, __VA_ARGS__); \
+ rcu_read_unlock(); \
+} while (0)
+
+#define rcu_str_deref(rcu_str) ({ \
+ struct rcu_string *__str = rcu_dereference(rcu_str); \
+ __str->str; \
+})
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index a38cfa4f251e..b223620cd5a6 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -26,6 +26,7 @@
#include "backref.h"
#include "extent_io.h"
#include "check-integrity.h"
+#include "rcu-string.h"
/*
* This is only the first step towards a full-features scrub. It reads all
@@ -320,10 +321,10 @@ static int scrub_print_warning_inode(u64 inum, u64 offset, u64 root, void *ctx)
* hold all of the paths here
*/
for (i = 0; i < ipath->fspath->elem_cnt; ++i)
- printk(KERN_WARNING "btrfs: %s at logical %llu on dev "
+ printk_in_rcu(KERN_WARNING "btrfs: %s at logical %llu on dev "
"%s, sector %llu, root %llu, inode %llu, offset %llu, "
"length %llu, links %u (path: %s)\n", swarn->errstr,
- swarn->logical, swarn->dev->name,
+ swarn->logical, rcu_str_deref(swarn->dev->name),
(unsigned long long)swarn->sector, root, inum, offset,
min(isize - offset, (u64)PAGE_SIZE), nlink,
(char *)(unsigned long)ipath->fspath->val[i]);
@@ -332,10 +333,10 @@ static int scrub_print_warning_inode(u64 inum, u64 offset, u64 root, void *ctx)
return 0;
err:
- printk(KERN_WARNING "btrfs: %s at logical %llu on dev "
+ printk_in_rcu(KERN_WARNING "btrfs: %s at logical %llu on dev "
"%s, sector %llu, root %llu, inode %llu, offset %llu: path "
"resolving failed with ret=%d\n", swarn->errstr,
- swarn->logical, swarn->dev->name,
+ swarn->logical, rcu_str_deref(swarn->dev->name),
(unsigned long long)swarn->sector, root, inum, offset, ret);
free_ipath(ipath);
@@ -390,10 +391,11 @@ static void scrub_print_warning(const char *errstr, struct scrub_block *sblock)
do {
ret = tree_backref_for_extent(&ptr, eb, ei, item_size,
&ref_root, &ref_level);
- printk(KERN_WARNING
+ printk_in_rcu(KERN_WARNING
"btrfs: %s at logical %llu on dev %s, "
"sector %llu: metadata %s (level %d) in tree "
- "%llu\n", errstr, swarn.logical, dev->name,
+ "%llu\n", errstr, swarn.logical,
+ rcu_str_deref(dev->name),
(unsigned long long)swarn.sector,
ref_level ? "node" : "leaf",
ret < 0 ? -1 : ref_level,
@@ -580,9 +582,11 @@ out:
spin_lock(&sdev->stat_lock);
++sdev->stat.uncorrectable_errors;
spin_unlock(&sdev->stat_lock);
- printk_ratelimited(KERN_ERR
+
+ printk_ratelimited_in_rcu(KERN_ERR
"btrfs: unable to fixup (nodatasum) error at logical %llu on dev %s\n",
- (unsigned long long)fixup->logical, sdev->dev->name);
+ (unsigned long long)fixup->logical,
+ rcu_str_deref(sdev->dev->name));
}
btrfs_free_path(path);
@@ -936,18 +940,20 @@ corrected_error:
spin_lock(&sdev->stat_lock);
sdev->stat.corrected_errors++;
spin_unlock(&sdev->stat_lock);
- printk_ratelimited(KERN_ERR
+ printk_ratelimited_in_rcu(KERN_ERR
"btrfs: fixed up error at logical %llu on dev %s\n",
- (unsigned long long)logical, sdev->dev->name);
+ (unsigned long long)logical,
+ rcu_str_deref(sdev->dev->name));
}
} else {
did_not_correct_error:
spin_lock(&sdev->stat_lock);
sdev->stat.uncorrectable_errors++;
spin_unlock(&sdev->stat_lock);
- printk_ratelimited(KERN_ERR
+ printk_ratelimited_in_rcu(KERN_ERR
"btrfs: unable to fixup (regular) error at logical %llu on dev %s\n",
- (unsigned long long)logical, sdev->dev->name);
+ (unsigned long long)logical,
+ rcu_str_deref(sdev->dev->name));
}
out:
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 96eb9fef7bd2..0eb9a4da069e 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -54,6 +54,7 @@
#include "version.h"
#include "export.h"
#include "compression.h"
+#include "rcu-string.h"
#define CREATE_TRACE_POINTS
#include <trace/events/btrfs.h>
@@ -1482,12 +1483,44 @@ static void btrfs_fs_dirty_inode(struct inode *inode, int flags)
"error %d\n", btrfs_ino(inode), ret);
}
+static int btrfs_show_devname(struct seq_file *m, struct dentry *root)
+{
+ struct btrfs_fs_info *fs_info = btrfs_sb(root->d_sb);
+ struct btrfs_fs_devices *cur_devices;
+ struct btrfs_device *dev, *first_dev = NULL;
+ struct list_head *head;
+ struct rcu_string *name;
+
+ mutex_lock(&fs_info->fs_devices->device_list_mutex);
+ cur_devices = fs_info->fs_devices;
+ while (cur_devices) {
+ head = &cur_devices->devices;
+ list_for_each_entry(dev, head, dev_list) {
+ if (!first_dev || dev->devid < first_dev->devid)
+ first_dev = dev;
+ }
+ cur_devices = cur_devices->seed;
+ }
+
+ if (first_dev) {
+ rcu_read_lock();
+ name = rcu_dereference(first_dev->name);
+ seq_escape(m, name->str, " \t\n\\");
+ rcu_read_unlock();
+ } else {
+ WARN_ON(1);
+ }
+ mutex_unlock(&fs_info->fs_devices->device_list_mutex);
+ return 0;
+}
+
static const struct super_operations btrfs_super_ops = {
.drop_inode = btrfs_drop_inode,
.evict_inode = btrfs_evict_inode,
.put_super = btrfs_put_super,
.sync_fs = btrfs_sync_fs,
.show_options = btrfs_show_options,
+ .show_devname = btrfs_show_devname,
.write_inode = btrfs_write_inode,
.dirty_inode = btrfs_fs_dirty_inode,
.alloc_inode = btrfs_alloc_inode,
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 1791c6e3d834..b72b068183ec 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -100,6 +100,10 @@ loop:
kmem_cache_free(btrfs_transaction_cachep, cur_trans);
cur_trans = fs_info->running_transaction;
goto loop;
+ } else if (root->fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) {
+ spin_unlock(&root->fs_info->trans_lock);
+ kmem_cache_free(btrfs_transaction_cachep, cur_trans);
+ return -EROFS;
}
atomic_set(&cur_trans->num_writers, 1);
@@ -1213,14 +1217,20 @@ int btrfs_commit_transaction_async(struct btrfs_trans_handle *trans,
static void cleanup_transaction(struct btrfs_trans_handle *trans,
- struct btrfs_root *root)
+ struct btrfs_root *root, int err)
{
struct btrfs_transaction *cur_trans = trans->transaction;
WARN_ON(trans->use_count > 1);
+ btrfs_abort_transaction(trans, root, err);
+
spin_lock(&root->fs_info->trans_lock);
list_del_init(&cur_trans->list);
+ if (cur_trans == root->fs_info->running_transaction) {
+ root->fs_info->running_transaction = NULL;
+ root->fs_info->trans_no_join = 0;
+ }
spin_unlock(&root->fs_info->trans_lock);
btrfs_cleanup_one_transaction(trans->transaction, root);
@@ -1526,7 +1536,7 @@ cleanup_transaction:
// WARN_ON(1);
if (current->journal_info == trans)
current->journal_info = NULL;
- cleanup_transaction(trans, root);
+ cleanup_transaction(trans, root, ret);
return ret;
}
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 7782020996fe..8a3d2594b807 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -35,6 +35,7 @@
#include "volumes.h"
#include "async-thread.h"
#include "check-integrity.h"
+#include "rcu-string.h"
static int init_first_rw_device(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
@@ -64,7 +65,7 @@ static void free_fs_devices(struct btrfs_fs_devices *fs_devices)
device = list_entry(fs_devices->devices.next,
struct btrfs_device, dev_list);
list_del(&device->dev_list);
- kfree(device->name);
+ rcu_string_free(device->name);
kfree(device);
}
kfree(fs_devices);
@@ -334,8 +335,8 @@ static noinline int device_list_add(const char *path,
{
struct btrfs_device *device;
struct btrfs_fs_devices *fs_devices;
+ struct rcu_string *name;
u64 found_transid = btrfs_super_generation(disk_super);
- char *name;
fs_devices = find_fsid(disk_super->fsid);
if (!fs_devices) {
@@ -369,11 +370,13 @@ static noinline int device_list_add(const char *path,
memcpy(device->uuid, disk_super->dev_item.uuid,
BTRFS_UUID_SIZE);
spin_lock_init(&device->io_lock);
- device->name = kstrdup(path, GFP_NOFS);
- if (!device->name) {
+
+ name = rcu_string_strdup(path, GFP_NOFS);
+ if (!name) {
kfree(device);
return -ENOMEM;
}
+ rcu_assign_pointer(device->name, name);
INIT_LIST_HEAD(&device->dev_alloc_list);
/* init readahead state */
@@ -390,12 +393,12 @@ static noinline int device_list_add(const char *path,
device->fs_devices = fs_devices;
fs_devices->num_devices++;
- } else if (!device->name || strcmp(device->name, path)) {
- name = kstrdup(path, GFP_NOFS);
+ } else if (!device->name || strcmp(device->name->str, path)) {
+ name = rcu_string_strdup(path, GFP_NOFS);
if (!name)
return -ENOMEM;
- kfree(device->name);
- device->name = name;
+ rcu_string_free(device->name);
+ rcu_assign_pointer(device->name, name);
if (device->missing) {
fs_devices->missing_devices--;
device->missing = 0;
@@ -430,15 +433,22 @@ static struct btrfs_fs_devices *clone_fs_devices(struct btrfs_fs_devices *orig)
/* We have held the volume lock, it is safe to get the devices. */
list_for_each_entry(orig_dev, &orig->devices, dev_list) {
+ struct rcu_string *name;
+
device = kzalloc(sizeof(*device), GFP_NOFS);
if (!device)
goto error;
- device->name = kstrdup(orig_dev->name, GFP_NOFS);
- if (!device->name) {
+ /*
+ * This is ok to do without rcu read locked because we hold the
+ * uuid mutex so nothing we touch in here is going to disappear.
+ */
+ name = rcu_string_strdup(orig_dev->name->str, GFP_NOFS);
+ if (!name) {
kfree(device);
goto error;
}
+ rcu_assign_pointer(device->name, name);
device->devid = orig_dev->devid;
device->work.func = pending_bios_fn;
@@ -491,7 +501,7 @@ again:
}
list_del_init(&device->dev_list);
fs_devices->num_devices--;
- kfree(device->name);
+ rcu_string_free(device->name);
kfree(device);
}
@@ -516,7 +526,7 @@ static void __free_device(struct work_struct *work)
if (device->bdev)
blkdev_put(device->bdev, device->mode);
- kfree(device->name);
+ rcu_string_free(device->name);
kfree(device);
}
@@ -540,6 +550,7 @@ static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
mutex_lock(&fs_devices->device_list_mutex);
list_for_each_entry(device, &fs_devices->devices, dev_list) {
struct btrfs_device *new_device;
+ struct rcu_string *name;
if (device->bdev)
fs_devices->open_devices--;
@@ -555,8 +566,11 @@ static int __btrfs_close_devices(struct btrfs_fs_devices *fs_devices)
new_device = kmalloc(sizeof(*new_device), GFP_NOFS);
BUG_ON(!new_device); /* -ENOMEM */
memcpy(new_device, device, sizeof(*new_device));
- new_device->name = kstrdup(device->name, GFP_NOFS);
- BUG_ON(device->name && !new_device->name); /* -ENOMEM */
+
+ /* Safe because we are under uuid_mutex */
+ name = rcu_string_strdup(device->name->str, GFP_NOFS);
+ BUG_ON(device->name && !name); /* -ENOMEM */
+ rcu_assign_pointer(new_device->name, name);
new_device->bdev = NULL;
new_device->writeable = 0;
new_device->in_fs_metadata = 0;
@@ -621,9 +635,9 @@ static int __btrfs_open_devices(struct btrfs_fs_devices *fs_devices,
if (!device->name)
continue;
- bdev = blkdev_get_by_path(device->name, flags, holder);
+ bdev = blkdev_get_by_path(device->name->str, flags, holder);
if (IS_ERR(bdev)) {
- printk(KERN_INFO "open %s failed\n", device->name);
+ printk(KERN_INFO "open %s failed\n", device->name->str);
goto error;
}
filemap_write_and_wait(bdev->bd_inode->i_mapping);
@@ -1632,6 +1646,7 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
struct block_device *bdev;
struct list_head *devices;
struct super_block *sb = root->fs_info->sb;
+ struct rcu_string *name;
u64 total_bytes;
int seeding_dev = 0;
int ret = 0;
@@ -1671,23 +1686,24 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
goto error;
}
- device->name = kstrdup(device_path, GFP_NOFS);
- if (!device->name) {
+ name = rcu_string_strdup(device_path, GFP_NOFS);
+ if (!name) {
kfree(device);
ret = -ENOMEM;
goto error;
}
+ rcu_assign_pointer(device->name, name);
ret = find_next_devid(root, &device->devid);
if (ret) {
- kfree(device->name);
+ rcu_string_free(device->name);
kfree(device);
goto error;
}
trans = btrfs_start_transaction(root, 0);
if (IS_ERR(trans)) {
- kfree(device->name);
+ rcu_string_free(device->name);
kfree(device);
ret = PTR_ERR(trans);
goto error;
@@ -1796,7 +1812,7 @@ error_trans:
unlock_chunks(root);
btrfs_abort_transaction(trans, root, ret);
btrfs_end_transaction(trans, root);
- kfree(device->name);
+ rcu_string_free(device->name);
kfree(device);
error:
blkdev_put(bdev, FMODE_EXCL);
@@ -4204,10 +4220,17 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
bio->bi_sector = bbio->stripes[dev_nr].physical >> 9;
dev = bbio->stripes[dev_nr].dev;
if (dev && dev->bdev && (rw != WRITE || dev->writeable)) {
+#ifdef DEBUG
+ struct rcu_string *name;
+
+ rcu_read_lock();
+ name = rcu_dereference(dev->name);
pr_debug("btrfs_map_bio: rw %d, secor=%llu, dev=%lu "
"(%s id %llu), size=%u\n", rw,
(u64)bio->bi_sector, (u_long)dev->bdev->bd_dev,
- dev->name, dev->devid, bio->bi_size);
+ name->str, dev->devid, bio->bi_size);
+ rcu_read_unlock();
+#endif
bio->bi_bdev = dev->bdev;
if (async_submit)
schedule_bio(root, dev, rw, bio);
@@ -4694,8 +4717,9 @@ int btrfs_init_dev_stats(struct btrfs_fs_info *fs_info)
key.offset = device->devid;
ret = btrfs_search_slot(NULL, dev_root, &key, path, 0, 0);
if (ret) {
- printk(KERN_WARNING "btrfs: no dev_stats entry found for device %s (devid %llu) (OK on first mount after mkfs)\n",
- device->name, (unsigned long long)device->devid);
+ printk_in_rcu(KERN_WARNING "btrfs: no dev_stats entry found for device %s (devid %llu) (OK on first mount after mkfs)\n",
+ rcu_str_deref(device->name),
+ (unsigned long long)device->devid);
__btrfs_reset_dev_stats(device);
device->dev_stats_valid = 1;
btrfs_release_path(path);
@@ -4747,8 +4771,8 @@ static int update_dev_stat_item(struct btrfs_trans_handle *trans,
BUG_ON(!path);
ret = btrfs_search_slot(trans, dev_root, &key, path, -1, 1);
if (ret < 0) {
- printk(KERN_WARNING "btrfs: error %d while searching for dev_stats item for device %s!\n",
- ret, device->name);
+ printk_in_rcu(KERN_WARNING "btrfs: error %d while searching for dev_stats item for device %s!\n",
+ ret, rcu_str_deref(device->name));
goto out;
}
@@ -4757,8 +4781,8 @@ static int update_dev_stat_item(struct btrfs_trans_handle *trans,
/* need to delete old one and insert a new one */
ret = btrfs_del_item(trans, dev_root, path);
if (ret != 0) {
- printk(KERN_WARNING "btrfs: delete too small dev_stats item for device %s failed %d!\n",
- device->name, ret);
+ printk_in_rcu(KERN_WARNING "btrfs: delete too small dev_stats item for device %s failed %d!\n",
+ rcu_str_deref(device->name), ret);
goto out;
}
ret = 1;
@@ -4770,8 +4794,8 @@ static int update_dev_stat_item(struct btrfs_trans_handle *trans,
ret = btrfs_insert_empty_item(trans, dev_root, path,
&key, sizeof(*ptr));
if (ret < 0) {
- printk(KERN_WARNING "btrfs: insert dev_stats item for device %s failed %d!\n",
- device->name, ret);
+ printk_in_rcu(KERN_WARNING "btrfs: insert dev_stats item for device %s failed %d!\n",
+ rcu_str_deref(device->name), ret);
goto out;
}
}
@@ -4823,9 +4847,9 @@ void btrfs_dev_stat_print_on_error(struct btrfs_device *dev)
{
if (!dev->dev_stats_valid)
return;
- printk_ratelimited(KERN_ERR
+ printk_ratelimited_in_rcu(KERN_ERR
"btrfs: bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n",
- dev->name,
+ rcu_str_deref(dev->name),
btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
@@ -4837,8 +4861,8 @@ void btrfs_dev_stat_print_on_error(struct btrfs_device *dev)
static void btrfs_dev_stat_print_on_load(struct btrfs_device *dev)
{
- printk(KERN_INFO "btrfs: bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n",
- dev->name,
+ printk_in_rcu(KERN_INFO "btrfs: bdev %s errs: wr %u, rd %u, flush %u, corrupt %u, gen %u\n",
+ rcu_str_deref(dev->name),
btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_WRITE_ERRS),
btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_READ_ERRS),
btrfs_dev_stat_read(dev, BTRFS_DEV_STAT_FLUSH_ERRS),
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 3406a88ca83e..74366f27a76b 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -58,7 +58,7 @@ struct btrfs_device {
/* the mode sent to blkdev_get */
fmode_t mode;
- char *name;
+ struct rcu_string *name;
/* the internal btrfs device id */
u64 devid;
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-10 06:56:52 +0000