* [PATCH 1/7] bcache: cached_dev_free needs to put the sb page
2019-12-09 9:38 bcache kbuild cleanups Christoph Hellwig
@ 2019-12-09 9:38 ` Christoph Hellwig
2019-12-09 9:38 ` [PATCH 2/7] bcache: use a separate data structure for the on-disk super block Christoph Hellwig
` (6 subsequent siblings)
7 siblings, 0 replies; 12+ messages in thread
From: Christoph Hellwig @ 2019-12-09 9:38 UTC (permalink / raw)
To: colyli; +Cc: kent.overstreet, liangchen.linux, linux-bcache, linux-block
From: Liang Chen <liangchen.linux@gmail.com>
Same as cache device, the buffer page needs to be put while
freeing cached_dev. Otherwise a page would be leaked every
time a cached_dev is stopped.
Signed-off-by: Liang Chen <liangchen.linux@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/md/bcache/super.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 77e9869345e7..a573ce1d85aa 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -1275,6 +1275,9 @@ static void cached_dev_free(struct closure *cl)
mutex_unlock(&bch_register_lock);
+ if (dc->sb_bio.bi_inline_vecs[0].bv_page)
+ put_page(bio_first_page_all(&dc->sb_bio));
+
if (!IS_ERR_OR_NULL(dc->bdev))
blkdev_put(dc->bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
--
2.20.1
^ permalink raw reply related [flat|nested] 12+ messages in thread* [PATCH 2/7] bcache: use a separate data structure for the on-disk super block
2019-12-09 9:38 bcache kbuild cleanups Christoph Hellwig
2019-12-09 9:38 ` [PATCH 1/7] bcache: cached_dev_free needs to put the sb page Christoph Hellwig
@ 2019-12-09 9:38 ` Christoph Hellwig
2019-12-09 9:38 ` [PATCH 3/7] bcache: rework error unwinding in register_bcache Christoph Hellwig
` (5 subsequent siblings)
7 siblings, 0 replies; 12+ messages in thread
From: Christoph Hellwig @ 2019-12-09 9:38 UTC (permalink / raw)
To: colyli; +Cc: kent.overstreet, liangchen.linux, linux-bcache, linux-block
Split out an on-disk version struct cache_sb with the proper endianess
annotations. This fixes a fair chunk of sparse warnings, but there are
some left due to the way the checksum is defined.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/md/bcache/super.c | 6 ++---
include/uapi/linux/bcache.h | 51 +++++++++++++++++++++++++++++++++++++
2 files changed, 54 insertions(+), 3 deletions(-)
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index a573ce1d85aa..3045f27e0d67 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -63,14 +63,14 @@ static const char *read_super(struct cache_sb *sb, struct block_device *bdev,
struct page **res)
{
const char *err;
- struct cache_sb *s;
+ struct cache_sb_disk *s;
struct buffer_head *bh = __bread(bdev, 1, SB_SIZE);
unsigned int i;
if (!bh)
return "IO error";
- s = (struct cache_sb *) bh->b_data;
+ s = (struct cache_sb_disk *)bh->b_data;
sb->offset = le64_to_cpu(s->offset);
sb->version = le64_to_cpu(s->version);
@@ -209,7 +209,7 @@ static void write_bdev_super_endio(struct bio *bio)
static void __write_super(struct cache_sb *sb, struct bio *bio)
{
- struct cache_sb *out = page_address(bio_first_page_all(bio));
+ struct cache_sb_disk *out = page_address(bio_first_page_all(bio));
unsigned int i;
bio->bi_iter.bi_sector = SB_SECTOR;
diff --git a/include/uapi/linux/bcache.h b/include/uapi/linux/bcache.h
index 5d4f58e059fd..1d8b3a9fc080 100644
--- a/include/uapi/linux/bcache.h
+++ b/include/uapi/linux/bcache.h
@@ -156,6 +156,57 @@ static inline struct bkey *bkey_idx(const struct bkey *k, unsigned int nr_keys)
#define BDEV_DATA_START_DEFAULT 16 /* sectors */
+struct cache_sb_disk {
+ __le64 csum;
+ __le64 offset; /* sector where this sb was written */
+ __le64 version;
+
+ __u8 magic[16];
+
+ __u8 uuid[16];
+ union {
+ __u8 set_uuid[16];
+ __le64 set_magic;
+ };
+ __u8 label[SB_LABEL_SIZE];
+
+ __le64 flags;
+ __le64 seq;
+ __le64 pad[8];
+
+ union {
+ struct {
+ /* Cache devices */
+ __le64 nbuckets; /* device size */
+
+ __le16 block_size; /* sectors */
+ __le16 bucket_size; /* sectors */
+
+ __le16 nr_in_set;
+ __le16 nr_this_dev;
+ };
+ struct {
+ /* Backing devices */
+ __le64 data_offset;
+
+ /*
+ * block_size from the cache device section is still used by
+ * backing devices, so don't add anything here until we fix
+ * things to not need it for backing devices anymore
+ */
+ };
+ };
+
+ __le32 last_mount; /* time overflow in y2106 */
+
+ __le16 first_bucket;
+ union {
+ __le16 njournal_buckets;
+ __le16 keys;
+ };
+ __le64 d[SB_JOURNAL_BUCKETS]; /* journal buckets */
+};
+
struct cache_sb {
__u64 csum;
__u64 offset; /* sector where this sb was written */
--
2.20.1
^ permalink raw reply related [flat|nested] 12+ messages in thread* [PATCH 3/7] bcache: rework error unwinding in register_bcache
2019-12-09 9:38 bcache kbuild cleanups Christoph Hellwig
2019-12-09 9:38 ` [PATCH 1/7] bcache: cached_dev_free needs to put the sb page Christoph Hellwig
2019-12-09 9:38 ` [PATCH 2/7] bcache: use a separate data structure for the on-disk super block Christoph Hellwig
@ 2019-12-09 9:38 ` Christoph Hellwig
2019-12-09 9:38 ` [PATCH 4/7] bcache: transfer the sb_page reference to register_{bdev,cache} Christoph Hellwig
` (4 subsequent siblings)
7 siblings, 0 replies; 12+ messages in thread
From: Christoph Hellwig @ 2019-12-09 9:38 UTC (permalink / raw)
To: colyli; +Cc: kent.overstreet, liangchen.linux, linux-bcache, linux-block
Split the successful and error return path, and use one goto label for each
resource to unwind. This also fixes some small errors like leaking the
module reference count in the reboot case (which seems entirely harmless)
or printing the wrong warning messages for early failures.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/md/bcache/super.c | 75 +++++++++++++++++++++++----------------
1 file changed, 45 insertions(+), 30 deletions(-)
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 3045f27e0d67..e8013e1b0a14 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -2375,29 +2375,33 @@ static bool bch_is_open(struct block_device *bdev)
static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
const char *buffer, size_t size)
{
- ssize_t ret = -EINVAL;
- const char *err = "cannot allocate memory";
- char *path = NULL;
- struct cache_sb *sb = NULL;
+ const char *err;
+ char *path;
+ struct cache_sb *sb;
struct block_device *bdev = NULL;
- struct page *sb_page = NULL;
+ struct page *sb_page;
+ ssize_t ret;
+ ret = -EBUSY;
if (!try_module_get(THIS_MODULE))
- return -EBUSY;
+ goto out;
/* For latest state of bcache_is_reboot */
smp_mb();
if (bcache_is_reboot)
- return -EBUSY;
+ goto out_module_put;
+ ret = -ENOMEM;
+ err = "cannot allocate memory";
path = kstrndup(buffer, size, GFP_KERNEL);
if (!path)
- goto err;
+ goto out_module_put;
sb = kmalloc(sizeof(struct cache_sb), GFP_KERNEL);
if (!sb)
- goto err;
+ goto out_free_path;
+ ret = -EINVAL;
err = "failed to open device";
bdev = blkdev_get_by_path(strim(path),
FMODE_READ|FMODE_WRITE|FMODE_EXCL,
@@ -2414,57 +2418,68 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
if (!IS_ERR(bdev))
bdput(bdev);
if (attr == &ksysfs_register_quiet)
- goto quiet_out;
+ goto done;
}
- goto err;
+ goto out_free_sb;
}
err = "failed to set blocksize";
if (set_blocksize(bdev, 4096))
- goto err_close;
+ goto out_blkdev_put;
err = read_super(sb, bdev, &sb_page);
if (err)
- goto err_close;
+ goto out_blkdev_put;
err = "failed to register device";
if (SB_IS_BDEV(sb)) {
struct cached_dev *dc = kzalloc(sizeof(*dc), GFP_KERNEL);
if (!dc)
- goto err_close;
+ goto out_put_sb_page;
mutex_lock(&bch_register_lock);
ret = register_bdev(sb, sb_page, bdev, dc);
mutex_unlock(&bch_register_lock);
/* blkdev_put() will be called in cached_dev_free() */
- if (ret < 0)
- goto err;
+ if (ret < 0) {
+ bdev = NULL;
+ goto out_put_sb_page;
+ }
} else {
struct cache *ca = kzalloc(sizeof(*ca), GFP_KERNEL);
if (!ca)
- goto err_close;
+ goto out_put_sb_page;
/* blkdev_put() will be called in bch_cache_release() */
- if (register_cache(sb, sb_page, bdev, ca) != 0)
- goto err;
+ if (register_cache(sb, sb_page, bdev, ca) != 0) {
+ bdev = NULL;
+ goto out_put_sb_page;
+ }
}
-quiet_out:
- ret = size;
-out:
- if (sb_page)
- put_page(sb_page);
+
+ put_page(sb_page);
+done:
kfree(sb);
kfree(path);
module_put(THIS_MODULE);
- return ret;
-
-err_close:
- blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
-err:
+ return size;
+
+out_put_sb_page:
+ put_page(sb_page);
+out_blkdev_put:
+ if (bdev)
+ blkdev_put(bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
+out_free_sb:
+ kfree(sb);
+out_free_path:
+ kfree(path);
+out_module_put:
+ module_put(THIS_MODULE);
+out:
pr_info("error %s: %s", path, err);
- goto out;
+ return ret;
}
--
2.20.1
^ permalink raw reply related [flat|nested] 12+ messages in thread* [PATCH 4/7] bcache: transfer the sb_page reference to register_{bdev,cache}
2019-12-09 9:38 bcache kbuild cleanups Christoph Hellwig
` (2 preceding siblings ...)
2019-12-09 9:38 ` [PATCH 3/7] bcache: rework error unwinding in register_bcache Christoph Hellwig
@ 2019-12-09 9:38 ` Christoph Hellwig
2019-12-09 9:38 ` [PATCH 5/7] bcache: return a pointer to the on-disk sb from read_super Christoph Hellwig
` (3 subsequent siblings)
7 siblings, 0 replies; 12+ messages in thread
From: Christoph Hellwig @ 2019-12-09 9:38 UTC (permalink / raw)
To: colyli; +Cc: kent.overstreet, liangchen.linux, linux-bcache, linux-block
Avoid an extra reference count roundtrip by transferring the sb_page
ownership to the lower level register helpers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/md/bcache/super.c | 21 ++++++---------------
1 file changed, 6 insertions(+), 15 deletions(-)
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index e8013e1b0a14..c11bc0135ae6 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -1368,8 +1368,6 @@ static int register_bdev(struct cache_sb *sb, struct page *sb_page,
bio_init(&dc->sb_bio, dc->sb_bio.bi_inline_vecs, 1);
bio_first_bvec_all(&dc->sb_bio)->bv_page = sb_page;
- get_page(sb_page);
-
if (cached_dev_init(dc, sb->block_size << 9))
goto err;
@@ -2275,7 +2273,6 @@ static int register_cache(struct cache_sb *sb, struct page *sb_page,
bio_init(&ca->sb_bio, ca->sb_bio.bi_inline_vecs, 1);
bio_first_bvec_all(&ca->sb_bio)->bv_page = sb_page;
- get_page(sb_page);
if (blk_queue_discard(bdev_get_queue(bdev)))
ca->discard = CACHE_DISCARD(&ca->sb);
@@ -2378,7 +2375,7 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
const char *err;
char *path;
struct cache_sb *sb;
- struct block_device *bdev = NULL;
+ struct block_device *bdev;
struct page *sb_page;
ssize_t ret;
@@ -2442,10 +2439,8 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
ret = register_bdev(sb, sb_page, bdev, dc);
mutex_unlock(&bch_register_lock);
/* blkdev_put() will be called in cached_dev_free() */
- if (ret < 0) {
- bdev = NULL;
- goto out_put_sb_page;
- }
+ if (ret < 0)
+ goto out_free_sb;
} else {
struct cache *ca = kzalloc(sizeof(*ca), GFP_KERNEL);
@@ -2453,13 +2448,10 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
goto out_put_sb_page;
/* blkdev_put() will be called in bch_cache_release() */
- if (register_cache(sb, sb_page, bdev, ca) != 0) {
- bdev = NULL;
- goto out_put_sb_page;
- }
+ if (register_cache(sb, sb_page, bdev, ca) != 0)
+ goto out_free_sb;
}
- put_page(sb_page);
done:
kfree(sb);
kfree(path);
@@ -2469,8 +2461,7 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
out_put_sb_page:
put_page(sb_page);
out_blkdev_put:
- if (bdev)
- blkdev_put(bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
+ blkdev_put(bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
out_free_sb:
kfree(sb);
out_free_path:
--
2.20.1
^ permalink raw reply related [flat|nested] 12+ messages in thread* [PATCH 5/7] bcache: return a pointer to the on-disk sb from read_super
2019-12-09 9:38 bcache kbuild cleanups Christoph Hellwig
` (3 preceding siblings ...)
2019-12-09 9:38 ` [PATCH 4/7] bcache: transfer the sb_page reference to register_{bdev,cache} Christoph Hellwig
@ 2019-12-09 9:38 ` Christoph Hellwig
2019-12-09 9:38 ` [PATCH 6/7] bcache: store a pointer to the on-disk sb in the cache and cached_dev structures Christoph Hellwig
` (2 subsequent siblings)
7 siblings, 0 replies; 12+ messages in thread
From: Christoph Hellwig @ 2019-12-09 9:38 UTC (permalink / raw)
To: colyli; +Cc: kent.overstreet, liangchen.linux, linux-bcache, linux-block
Returning the properly typed actual data structure insteaf of the
containing struct page will save the callers some work going
forward.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/md/bcache/super.c | 22 +++++++++++-----------
1 file changed, 11 insertions(+), 11 deletions(-)
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index c11bc0135ae6..0b7620d9f087 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -60,7 +60,7 @@ struct workqueue_struct *bch_journal_wq;
/* Superblock */
static const char *read_super(struct cache_sb *sb, struct block_device *bdev,
- struct page **res)
+ struct cache_sb_disk **res)
{
const char *err;
struct cache_sb_disk *s;
@@ -191,7 +191,7 @@ static const char *read_super(struct cache_sb *sb, struct block_device *bdev,
err = NULL;
get_page(bh->b_page);
- *res = bh->b_page;
+ *res = s;
err:
put_bh(bh);
return err;
@@ -1353,7 +1353,7 @@ static int cached_dev_init(struct cached_dev *dc, unsigned int block_size)
/* Cached device - bcache superblock */
-static int register_bdev(struct cache_sb *sb, struct page *sb_page,
+static int register_bdev(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
struct block_device *bdev,
struct cached_dev *dc)
{
@@ -1367,7 +1367,7 @@ static int register_bdev(struct cache_sb *sb, struct page *sb_page,
dc->bdev->bd_holder = dc;
bio_init(&dc->sb_bio, dc->sb_bio.bi_inline_vecs, 1);
- bio_first_bvec_all(&dc->sb_bio)->bv_page = sb_page;
+ bio_first_bvec_all(&dc->sb_bio)->bv_page = virt_to_page(sb_disk);
if (cached_dev_init(dc, sb->block_size << 9))
goto err;
@@ -2260,7 +2260,7 @@ static int cache_alloc(struct cache *ca)
return ret;
}
-static int register_cache(struct cache_sb *sb, struct page *sb_page,
+static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
struct block_device *bdev, struct cache *ca)
{
const char *err = NULL; /* must be set for any error case */
@@ -2272,7 +2272,7 @@ static int register_cache(struct cache_sb *sb, struct page *sb_page,
ca->bdev->bd_holder = ca;
bio_init(&ca->sb_bio, ca->sb_bio.bi_inline_vecs, 1);
- bio_first_bvec_all(&ca->sb_bio)->bv_page = sb_page;
+ bio_first_bvec_all(&ca->sb_bio)->bv_page = virt_to_page(sb_disk);
if (blk_queue_discard(bdev_get_queue(bdev)))
ca->discard = CACHE_DISCARD(&ca->sb);
@@ -2375,8 +2375,8 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
const char *err;
char *path;
struct cache_sb *sb;
+ struct cache_sb_disk *sb_disk;
struct block_device *bdev;
- struct page *sb_page;
ssize_t ret;
ret = -EBUSY;
@@ -2424,7 +2424,7 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
if (set_blocksize(bdev, 4096))
goto out_blkdev_put;
- err = read_super(sb, bdev, &sb_page);
+ err = read_super(sb, bdev, &sb_disk);
if (err)
goto out_blkdev_put;
@@ -2436,7 +2436,7 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
goto out_put_sb_page;
mutex_lock(&bch_register_lock);
- ret = register_bdev(sb, sb_page, bdev, dc);
+ ret = register_bdev(sb, sb_disk, bdev, dc);
mutex_unlock(&bch_register_lock);
/* blkdev_put() will be called in cached_dev_free() */
if (ret < 0)
@@ -2448,7 +2448,7 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
goto out_put_sb_page;
/* blkdev_put() will be called in bch_cache_release() */
- if (register_cache(sb, sb_page, bdev, ca) != 0)
+ if (register_cache(sb, sb_disk, bdev, ca) != 0)
goto out_free_sb;
}
@@ -2459,7 +2459,7 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
return size;
out_put_sb_page:
- put_page(sb_page);
+ put_page(virt_to_page(sb_disk));
out_blkdev_put:
blkdev_put(bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
out_free_sb:
--
2.20.1
^ permalink raw reply related [flat|nested] 12+ messages in thread* [PATCH 6/7] bcache: store a pointer to the on-disk sb in the cache and cached_dev structures
2019-12-09 9:38 bcache kbuild cleanups Christoph Hellwig
` (4 preceding siblings ...)
2019-12-09 9:38 ` [PATCH 5/7] bcache: return a pointer to the on-disk sb from read_super Christoph Hellwig
@ 2019-12-09 9:38 ` Christoph Hellwig
2019-12-09 9:38 ` [PATCH 7/7] bcache: use read_cache_page_gfp to read the superblock Christoph Hellwig
2019-12-09 9:59 ` bcache kbuild cleanups Coly Li
7 siblings, 0 replies; 12+ messages in thread
From: Christoph Hellwig @ 2019-12-09 9:38 UTC (permalink / raw)
To: colyli; +Cc: kent.overstreet, liangchen.linux, linux-bcache, linux-block
This allows to properly build the superblock bio including the offset in the
page using the normal bio helpers. This fixes writing the superblock for
page sizes larger than 4k where the sb write bio would need an offset in the
bio_vec.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/md/bcache/bcache.h | 2 ++
drivers/md/bcache/super.c | 32 +++++++++++++-------------------
2 files changed, 15 insertions(+), 19 deletions(-)
diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
index 9198c1b480d9..adf26a21fcd1 100644
--- a/drivers/md/bcache/bcache.h
+++ b/drivers/md/bcache/bcache.h
@@ -301,6 +301,7 @@ struct cached_dev {
struct block_device *bdev;
struct cache_sb sb;
+ struct cache_sb_disk *sb_disk;
struct bio sb_bio;
struct bio_vec sb_bv[1];
struct closure sb_write;
@@ -403,6 +404,7 @@ enum alloc_reserve {
struct cache {
struct cache_set *set;
struct cache_sb sb;
+ struct cache_sb_disk *sb_disk;
struct bio sb_bio;
struct bio_vec sb_bv[1];
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 0b7620d9f087..df41d103fa34 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -207,15 +207,15 @@ static void write_bdev_super_endio(struct bio *bio)
closure_put(&dc->sb_write);
}
-static void __write_super(struct cache_sb *sb, struct bio *bio)
+static void __write_super(struct cache_sb *sb, struct cache_sb_disk *out,
+ struct bio *bio)
{
- struct cache_sb_disk *out = page_address(bio_first_page_all(bio));
unsigned int i;
+ bio->bi_opf = REQ_OP_WRITE | REQ_SYNC | REQ_META;
bio->bi_iter.bi_sector = SB_SECTOR;
- bio->bi_iter.bi_size = SB_SIZE;
- bio_set_op_attrs(bio, REQ_OP_WRITE, REQ_SYNC|REQ_META);
- bch_bio_map(bio, NULL);
+ __bio_add_page(bio, virt_to_page(out), SB_SIZE,
+ offset_in_page(out));
out->offset = cpu_to_le64(sb->offset);
out->version = cpu_to_le64(sb->version);
@@ -257,14 +257,14 @@ void bch_write_bdev_super(struct cached_dev *dc, struct closure *parent)
down(&dc->sb_write_mutex);
closure_init(cl, parent);
- bio_reset(bio);
+ bio_init(bio, dc->sb_bv, 1);
bio_set_dev(bio, dc->bdev);
bio->bi_end_io = write_bdev_super_endio;
bio->bi_private = dc;
closure_get(cl);
/* I/O request sent to backing device */
- __write_super(&dc->sb, bio);
+ __write_super(&dc->sb, dc->sb_disk, bio);
closure_return_with_destructor(cl, bch_write_bdev_super_unlock);
}
@@ -306,13 +306,13 @@ void bcache_write_super(struct cache_set *c)
SET_CACHE_SYNC(&ca->sb, CACHE_SYNC(&c->sb));
- bio_reset(bio);
+ bio_init(bio, ca->sb_bv, 1);
bio_set_dev(bio, ca->bdev);
bio->bi_end_io = write_super_endio;
bio->bi_private = ca;
closure_get(cl);
- __write_super(&ca->sb, bio);
+ __write_super(&ca->sb, ca->sb_disk, bio);
}
closure_return_with_destructor(cl, bcache_write_super_unlock);
@@ -1275,8 +1275,8 @@ static void cached_dev_free(struct closure *cl)
mutex_unlock(&bch_register_lock);
- if (dc->sb_bio.bi_inline_vecs[0].bv_page)
- put_page(bio_first_page_all(&dc->sb_bio));
+ if (dc->sb_disk)
+ put_page(virt_to_page(dc->sb_disk));
if (!IS_ERR_OR_NULL(dc->bdev))
blkdev_put(dc->bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
@@ -1366,9 +1366,6 @@ static int register_bdev(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
dc->bdev = bdev;
dc->bdev->bd_holder = dc;
- bio_init(&dc->sb_bio, dc->sb_bio.bi_inline_vecs, 1);
- bio_first_bvec_all(&dc->sb_bio)->bv_page = virt_to_page(sb_disk);
-
if (cached_dev_init(dc, sb->block_size << 9))
goto err;
@@ -2137,8 +2134,8 @@ void bch_cache_release(struct kobject *kobj)
for (i = 0; i < RESERVE_NR; i++)
free_fifo(&ca->free[i]);
- if (ca->sb_bio.bi_inline_vecs[0].bv_page)
- put_page(bio_first_page_all(&ca->sb_bio));
+ if (ca->sb_disk)
+ put_page(virt_to_page(ca->sb_disk));
if (!IS_ERR_OR_NULL(ca->bdev))
blkdev_put(ca->bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
@@ -2271,9 +2268,6 @@ static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
ca->bdev = bdev;
ca->bdev->bd_holder = ca;
- bio_init(&ca->sb_bio, ca->sb_bio.bi_inline_vecs, 1);
- bio_first_bvec_all(&ca->sb_bio)->bv_page = virt_to_page(sb_disk);
-
if (blk_queue_discard(bdev_get_queue(bdev)))
ca->discard = CACHE_DISCARD(&ca->sb);
--
2.20.1
^ permalink raw reply related [flat|nested] 12+ messages in thread* [PATCH 7/7] bcache: use read_cache_page_gfp to read the superblock
2019-12-09 9:38 bcache kbuild cleanups Christoph Hellwig
` (5 preceding siblings ...)
2019-12-09 9:38 ` [PATCH 6/7] bcache: store a pointer to the on-disk sb in the cache and cached_dev structures Christoph Hellwig
@ 2019-12-09 9:38 ` Christoph Hellwig
2019-12-09 9:59 ` bcache kbuild cleanups Coly Li
7 siblings, 0 replies; 12+ messages in thread
From: Christoph Hellwig @ 2019-12-09 9:38 UTC (permalink / raw)
To: colyli; +Cc: kent.overstreet, liangchen.linux, linux-bcache, linux-block
Avoid a pointless dependency on buffer heads in bcache by simply open
coding reading a single page. Also add a SB_OFFSET define for the
byte offset of the superblock instead of using magic numbers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/md/bcache/super.c | 16 +++++++---------
include/uapi/linux/bcache.h | 1 +
2 files changed, 8 insertions(+), 9 deletions(-)
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index df41d103fa34..ecb24316381f 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -15,7 +15,6 @@
#include "writeback.h"
#include <linux/blkdev.h>
-#include <linux/buffer_head.h>
#include <linux/debugfs.h>
#include <linux/genhd.h>
#include <linux/idr.h>
@@ -64,13 +63,14 @@ static const char *read_super(struct cache_sb *sb, struct block_device *bdev,
{
const char *err;
struct cache_sb_disk *s;
- struct buffer_head *bh = __bread(bdev, 1, SB_SIZE);
+ struct page *page;
unsigned int i;
- if (!bh)
+ page = read_cache_page_gfp(bdev->bd_inode->i_mapping,
+ SB_OFFSET >> PAGE_SHIFT, GFP_KERNEL);
+ if (IS_ERR(page))
return "IO error";
-
- s = (struct cache_sb_disk *)bh->b_data;
+ s = page_address(page) + offset_in_page(SB_OFFSET);
sb->offset = le64_to_cpu(s->offset);
sb->version = le64_to_cpu(s->version);
@@ -188,12 +188,10 @@ static const char *read_super(struct cache_sb *sb, struct block_device *bdev,
}
sb->last_mount = (u32)ktime_get_real_seconds();
- err = NULL;
-
- get_page(bh->b_page);
*res = s;
+ return NULL;
err:
- put_bh(bh);
+ put_page(page);
return err;
}
diff --git a/include/uapi/linux/bcache.h b/include/uapi/linux/bcache.h
index 1d8b3a9fc080..9a1965c6c3d0 100644
--- a/include/uapi/linux/bcache.h
+++ b/include/uapi/linux/bcache.h
@@ -148,6 +148,7 @@ static inline struct bkey *bkey_idx(const struct bkey *k, unsigned int nr_keys)
#define BCACHE_SB_MAX_VERSION 4
#define SB_SECTOR 8
+#define SB_OFFSET (SB_SECTOR << SECTOR_SHIFT)
#define SB_SIZE 4096
#define SB_LABEL_SIZE 32
#define SB_JOURNAL_BUCKETS 256U
--
2.20.1
^ permalink raw reply related [flat|nested] 12+ messages in thread* Re: bcache kbuild cleanups
2019-12-09 9:38 bcache kbuild cleanups Christoph Hellwig
` (6 preceding siblings ...)
2019-12-09 9:38 ` [PATCH 7/7] bcache: use read_cache_page_gfp to read the superblock Christoph Hellwig
@ 2019-12-09 9:59 ` Coly Li
2019-12-11 15:17 ` Liang C
7 siblings, 1 reply; 12+ messages in thread
From: Coly Li @ 2019-12-09 9:59 UTC (permalink / raw)
To: Christoph Hellwig
Cc: kent.overstreet, liangchen.linux, linux-bcache, linux-block
On 2019/12/9 5:38 下午, Christoph Hellwig wrote:
> Hi Coly and Liang,
>
> can you review this series to sort out the bcache superblock reading for
> larger page sizes? I don't have bcache test setup so this is compile
> tested only.
>
Hi Christoph,
At first glance the patches are good. I will add them into my for-test
directory and test with other development patches.
Thanks for handling this.
--
Coly Li
^ permalink raw reply [flat|nested] 12+ messages in thread* Re: bcache kbuild cleanups
2019-12-09 9:59 ` bcache kbuild cleanups Coly Li
@ 2019-12-11 15:17 ` Liang C
2019-12-12 15:34 ` Christoph Hellwig
0 siblings, 1 reply; 12+ messages in thread
From: Liang C @ 2019-12-11 15:17 UTC (permalink / raw)
To: Christoph Hellwig; +Cc: Coly Li, Kent Overstreet, linux-bcache, linux-block
> Hi Coly and Liang,
>
> can you review this series to sort out the bcache superblock reading for
> larger page sizes? I don't have bcache test setup so this is compile
> tested only.
>
Hi Christoph,
Thanks for making the patches. I looked through them, but didn't see
where cache and cached_dev have their sb_disk assigned.
That would be an issue when __write_super tries to add the
corresponding page to the bio. Not sure if there is there anything I
missed.
Liang
^ permalink raw reply [flat|nested] 12+ messages in thread
* Re: bcache kbuild cleanups
2019-12-11 15:17 ` Liang C
@ 2019-12-12 15:34 ` Christoph Hellwig
0 siblings, 0 replies; 12+ messages in thread
From: Christoph Hellwig @ 2019-12-12 15:34 UTC (permalink / raw)
To: Liang C
Cc: Christoph Hellwig, Coly Li, Kent Overstreet, linux-bcache, linux-block
On Wed, Dec 11, 2019 at 11:17:44PM +0800, Liang C wrote:
> > Hi Coly and Liang,
> >
> > can you review this series to sort out the bcache superblock reading for
> > larger page sizes? I don't have bcache test setup so this is compile
> > tested only.
> >
> Hi Christoph,
>
> Thanks for making the patches. I looked through them, but didn't see
> where cache and cached_dev have their sb_disk assigned.
> That would be an issue when __write_super tries to add the
> corresponding page to the bio. Not sure if there is there anything I
> missed.
Yes, that was missing.
^ permalink raw reply [flat|nested] 12+ messages in thread
* [PATCH 6/7] bcache: store a pointer to the on-disk sb in the cache and cached_dev structures
2019-12-12 15:35 bcache superblock reading / writing v2 Christoph Hellwig
@ 2019-12-12 15:36 ` Christoph Hellwig
0 siblings, 0 replies; 12+ messages in thread
From: Christoph Hellwig @ 2019-12-12 15:36 UTC (permalink / raw)
To: colyli; +Cc: kent.overstreet, liangchen.linux, linux-bcache, linux-block
This allows to properly build the superblock bio including the offset in the
page using the normal bio helpers. This fixes writing the superblock for
page sizes larger than 4k where the sb write bio would need an offset in the
bio_vec.
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/md/bcache/bcache.h | 2 ++
drivers/md/bcache/super.c | 34 +++++++++++++++-------------------
2 files changed, 17 insertions(+), 19 deletions(-)
diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
index 9198c1b480d9..adf26a21fcd1 100644
--- a/drivers/md/bcache/bcache.h
+++ b/drivers/md/bcache/bcache.h
@@ -301,6 +301,7 @@ struct cached_dev {
struct block_device *bdev;
struct cache_sb sb;
+ struct cache_sb_disk *sb_disk;
struct bio sb_bio;
struct bio_vec sb_bv[1];
struct closure sb_write;
@@ -403,6 +404,7 @@ enum alloc_reserve {
struct cache {
struct cache_set *set;
struct cache_sb sb;
+ struct cache_sb_disk *sb_disk;
struct bio sb_bio;
struct bio_vec sb_bv[1];
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 0b7620d9f087..c3bfbc813daf 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -207,15 +207,15 @@ static void write_bdev_super_endio(struct bio *bio)
closure_put(&dc->sb_write);
}
-static void __write_super(struct cache_sb *sb, struct bio *bio)
+static void __write_super(struct cache_sb *sb, struct cache_sb_disk *out,
+ struct bio *bio)
{
- struct cache_sb_disk *out = page_address(bio_first_page_all(bio));
unsigned int i;
+ bio->bi_opf = REQ_OP_WRITE | REQ_SYNC | REQ_META;
bio->bi_iter.bi_sector = SB_SECTOR;
- bio->bi_iter.bi_size = SB_SIZE;
- bio_set_op_attrs(bio, REQ_OP_WRITE, REQ_SYNC|REQ_META);
- bch_bio_map(bio, NULL);
+ __bio_add_page(bio, virt_to_page(out), SB_SIZE,
+ offset_in_page(out));
out->offset = cpu_to_le64(sb->offset);
out->version = cpu_to_le64(sb->version);
@@ -257,14 +257,14 @@ void bch_write_bdev_super(struct cached_dev *dc, struct closure *parent)
down(&dc->sb_write_mutex);
closure_init(cl, parent);
- bio_reset(bio);
+ bio_init(bio, dc->sb_bv, 1);
bio_set_dev(bio, dc->bdev);
bio->bi_end_io = write_bdev_super_endio;
bio->bi_private = dc;
closure_get(cl);
/* I/O request sent to backing device */
- __write_super(&dc->sb, bio);
+ __write_super(&dc->sb, dc->sb_disk, bio);
closure_return_with_destructor(cl, bch_write_bdev_super_unlock);
}
@@ -306,13 +306,13 @@ void bcache_write_super(struct cache_set *c)
SET_CACHE_SYNC(&ca->sb, CACHE_SYNC(&c->sb));
- bio_reset(bio);
+ bio_init(bio, ca->sb_bv, 1);
bio_set_dev(bio, ca->bdev);
bio->bi_end_io = write_super_endio;
bio->bi_private = ca;
closure_get(cl);
- __write_super(&ca->sb, bio);
+ __write_super(&ca->sb, ca->sb_disk, bio);
}
closure_return_with_destructor(cl, bcache_write_super_unlock);
@@ -1275,8 +1275,8 @@ static void cached_dev_free(struct closure *cl)
mutex_unlock(&bch_register_lock);
- if (dc->sb_bio.bi_inline_vecs[0].bv_page)
- put_page(bio_first_page_all(&dc->sb_bio));
+ if (dc->sb_disk)
+ put_page(virt_to_page(dc->sb_disk));
if (!IS_ERR_OR_NULL(dc->bdev))
blkdev_put(dc->bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
@@ -1365,9 +1365,7 @@ static int register_bdev(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
memcpy(&dc->sb, sb, sizeof(struct cache_sb));
dc->bdev = bdev;
dc->bdev->bd_holder = dc;
-
- bio_init(&dc->sb_bio, dc->sb_bio.bi_inline_vecs, 1);
- bio_first_bvec_all(&dc->sb_bio)->bv_page = virt_to_page(sb_disk);
+ dc->sb_disk = sb_disk;
if (cached_dev_init(dc, sb->block_size << 9))
goto err;
@@ -2137,8 +2135,8 @@ void bch_cache_release(struct kobject *kobj)
for (i = 0; i < RESERVE_NR; i++)
free_fifo(&ca->free[i]);
- if (ca->sb_bio.bi_inline_vecs[0].bv_page)
- put_page(bio_first_page_all(&ca->sb_bio));
+ if (ca->sb_disk)
+ put_page(virt_to_page(ca->sb_disk));
if (!IS_ERR_OR_NULL(ca->bdev))
blkdev_put(ca->bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
@@ -2270,9 +2268,7 @@ static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
memcpy(&ca->sb, sb, sizeof(struct cache_sb));
ca->bdev = bdev;
ca->bdev->bd_holder = ca;
-
- bio_init(&ca->sb_bio, ca->sb_bio.bi_inline_vecs, 1);
- bio_first_bvec_all(&ca->sb_bio)->bv_page = virt_to_page(sb_disk);
+ ca->sb_disk = sb_disk;
if (blk_queue_discard(bdev_get_queue(bdev)))
ca->discard = CACHE_DISCARD(&ca->sb);
--
2.20.1
^ permalink raw reply related [flat|nested] 12+ messages in thread