[PATCH 06/71] block: get rid of PAGE_CACHE_* and page_cache_{get,release} macros

From: Kirill A. Shutemov
Date: Sun Mar 20 2016 - 14:44:17 EST

PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago
with promise that one day it will be possible to implement page cache with
bigger chunks than PAGE_SIZE.

This promise never materialized. And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_*
or PAGE_* constant should be used in a particular case, especially on the
border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special. They are not.

The changes are pretty straight-forward:

- <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

- PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

- page_cache_get() -> get_page();

- page_cache_release() -> put_page();

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: Jens Axboe <axboe@xxxxxxxxx>
Cc: Philipp Reisner <philipp.reisner@xxxxxxxxxx>
Cc: Lars Ellenberg <lars.ellenberg@xxxxxxxxxx>
Cc: "Ed L. Cashin" <ed.cashin@xxxxxxx>
---
block/bio.c | 12 ++++++------
block/blk-core.c | 2 +-
block/blk-settings.c | 12 ++++++------
block/blk-sysfs.c | 8 ++++----
block/cfq-iosched.c | 2 +-
block/compat_ioctl.c | 4 ++--
block/ioctl.c | 4 ++--
block/partition-generic.c | 8 ++++----
drivers/block/aoe/aoeblk.c | 2 +-
drivers/block/brd.c | 2 +-
drivers/block/drbd/drbd_int.h | 4 ++--
drivers/block/drbd/drbd_nl.c | 2 +-
include/linux/backing-dev-defs.h | 2 +-
include/linux/bio.h | 2 +-
include/linux/blkdev.h | 2 +-
15 files changed, 34 insertions(+), 34 deletions(-)

diff --git a/block/bio.c b/block/bio.c
index f124a0a624fc..807d25e466ec 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -1339,7 +1339,7 @@ struct bio *bio_map_user_iov(struct request_queue *q,
* release the pages we didn't map into the bio, if any
*/
while (j < page_limit)
- page_cache_release(pages[j++]);
+ put_page(pages[j++]);
}

kfree(pages);
@@ -1365,7 +1365,7 @@ struct bio *bio_map_user_iov(struct request_queue *q,
for (j = 0; j < nr_pages; j++) {
if (!pages[j])
break;
- page_cache_release(pages[j]);
+ put_page(pages[j]);
}
out:
kfree(pages);
@@ -1385,7 +1385,7 @@ static void __bio_unmap_user(struct bio *bio)
if (bio_data_dir(bio) == READ)
set_page_dirty_lock(bvec->bv_page);

- page_cache_release(bvec->bv_page);
+ put_page(bvec->bv_page);
}

bio_put(bio);
@@ -1615,8 +1615,8 @@ static void bio_release_pages(struct bio *bio)
* the BIO and the offending pages and re-dirty the pages in process context.
*
* It is expected that bio_check_pages_dirty() will wholly own the BIO from
- * here on. It will run one page_cache_release() against each page and will
- * run one bio_put() against the BIO.
+ * here on. It will run one put_page() against each page and will run one
+ * bio_put() against the BIO.
*/

static void bio_dirty_fn(struct work_struct *work);
@@ -1658,7 +1658,7 @@ void bio_check_pages_dirty(struct bio *bio)
struct page *page = bvec->bv_page;

if (PageDirty(page) || PageCompound(page)) {
- page_cache_release(page);
+ put_page(page);
bvec->bv_page = NULL;
} else {
nr_clean_pages++;
diff --git a/block/blk-core.c b/block/blk-core.c
index 827f8badd143..b60537b2c35b 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -706,7 +706,7 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id)
goto fail_id;

q->backing_dev_info.ra_pages =
- (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;
+ (VM_MAX_READAHEAD * 1024) / PAGE_SIZE;
q->backing_dev_info.capabilities = BDI_CAP_CGROUP_WRITEBACK;
q->backing_dev_info.name = "block";
q->node = node_id;
diff --git a/block/blk-settings.c b/block/blk-settings.c
index c7bb666aafd1..331e4eee0dda 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -239,8 +239,8 @@ void blk_queue_max_hw_sectors(struct request_queue *q, unsigned int max_hw_secto
struct queue_limits *limits = &q->limits;
unsigned int max_sectors;

- if ((max_hw_sectors << 9) < PAGE_CACHE_SIZE) {
- max_hw_sectors = 1 << (PAGE_CACHE_SHIFT - 9);
+ if ((max_hw_sectors << 9) < PAGE_SIZE) {
+ max_hw_sectors = 1 << (PAGE_SHIFT - 9);
printk(KERN_INFO "%s: set to minimum %d\n",
__func__, max_hw_sectors);
}
@@ -329,8 +329,8 @@ EXPORT_SYMBOL(blk_queue_max_segments);
**/
void blk_queue_max_segment_size(struct request_queue *q, unsigned int max_size)
{
- if (max_size < PAGE_CACHE_SIZE) {
- max_size = PAGE_CACHE_SIZE;
+ if (max_size < PAGE_SIZE) {
+ max_size = PAGE_SIZE;
printk(KERN_INFO "%s: set to minimum %d\n",
__func__, max_size);
}
@@ -760,8 +760,8 @@ EXPORT_SYMBOL_GPL(blk_queue_dma_drain);
**/
void blk_queue_segment_boundary(struct request_queue *q, unsigned long mask)
{
- if (mask < PAGE_CACHE_SIZE - 1) {
- mask = PAGE_CACHE_SIZE - 1;
+ if (mask < PAGE_SIZE - 1) {
+ mask = PAGE_SIZE - 1;
printk(KERN_INFO "%s: set to minimum %lx\n",
__func__, mask);
}
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index dd93763057ce..995b58d46ed1 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -76,7 +76,7 @@ queue_requests_store(struct request_queue *q, const char *page, size_t count)
static ssize_t queue_ra_show(struct request_queue *q, char *page)
{
unsigned long ra_kb = q->backing_dev_info.ra_pages <<
- (PAGE_CACHE_SHIFT - 10);
+ (PAGE_SHIFT - 10);

return queue_var_show(ra_kb, (page));
}
@@ -90,7 +90,7 @@ queue_ra_store(struct request_queue *q, const char *page, size_t count)
if (ret < 0)
return ret;

- q->backing_dev_info.ra_pages = ra_kb >> (PAGE_CACHE_SHIFT - 10);
+ q->backing_dev_info.ra_pages = ra_kb >> (PAGE_SHIFT - 10);

return ret;
}
@@ -117,7 +117,7 @@ static ssize_t queue_max_segment_size_show(struct request_queue *q, char *page)
if (blk_queue_cluster(q))
return queue_var_show(queue_max_segment_size(q), (page));

- return queue_var_show(PAGE_CACHE_SIZE, (page));
+ return queue_var_show(PAGE_SIZE, (page));
}

static ssize_t queue_logical_block_size_show(struct request_queue *q, char *page)
@@ -198,7 +198,7 @@ queue_max_sectors_store(struct request_queue *q, const char *page, size_t count)
{
unsigned long max_sectors_kb,
max_hw_sectors_kb = queue_max_hw_sectors(q) >> 1,
- page_kb = 1 << (PAGE_CACHE_SHIFT - 10);
+ page_kb = 1 << (PAGE_SHIFT - 10);
ssize_t ret = queue_var_store(&max_sectors_kb, page, count);

if (ret < 0)
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index e3c591dd8f19..4a349787bc62 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -4075,7 +4075,7 @@ cfq_rq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq,
* idle timer unplug to continue working.
*/
if (cfq_cfqq_wait_request(cfqq)) {
- if (blk_rq_bytes(rq) > PAGE_CACHE_SIZE ||
+ if (blk_rq_bytes(rq) > PAGE_SIZE ||
cfqd->busy_queues > 1) {
cfq_del_timer(cfqd, cfqq);
cfq_clear_cfqq_wait_request(cfqq);
diff --git a/block/compat_ioctl.c b/block/compat_ioctl.c
index f678c733df40..556826ac7cb4 100644
--- a/block/compat_ioctl.c
+++ b/block/compat_ioctl.c
@@ -710,7 +710,7 @@ long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
return -EINVAL;
bdi = blk_get_backing_dev_info(bdev);
return compat_put_long(arg,
- (bdi->ra_pages * PAGE_CACHE_SIZE) / 512);
+ (bdi->ra_pages * PAGE_SIZE) / 512);
case BLKROGET: /* compatible */
return compat_put_int(arg, bdev_read_only(bdev) != 0);
case BLKBSZGET_32: /* get the logical block size (cf. BLKSSZGET) */
@@ -729,7 +729,7 @@ long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
bdi = blk_get_backing_dev_info(bdev);
- bdi->ra_pages = (arg * 512) / PAGE_CACHE_SIZE;
+ bdi->ra_pages = (arg * 512) / PAGE_SIZE;
return 0;
case BLKGETSIZE:
size = i_size_read(bdev->bd_inode);
diff --git a/block/ioctl.c b/block/ioctl.c
index d8996bbd7f12..4ff1f92f89ca 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -550,7 +550,7 @@ int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
if (!arg)
return -EINVAL;
bdi = blk_get_backing_dev_info(bdev);
- return put_long(arg, (bdi->ra_pages * PAGE_CACHE_SIZE) / 512);
+ return put_long(arg, (bdi->ra_pages * PAGE_SIZE) / 512);
case BLKROGET:
return put_int(arg, bdev_read_only(bdev) != 0);
case BLKBSZGET: /* get block device soft block size (cf. BLKSSZGET) */
@@ -578,7 +578,7 @@ int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
if(!capable(CAP_SYS_ADMIN))
return -EACCES;
bdi = blk_get_backing_dev_info(bdev);
- bdi->ra_pages = (arg * 512) / PAGE_CACHE_SIZE;
+ bdi->ra_pages = (arg * 512) / PAGE_SIZE;
return 0;
case BLKBSZSET:
return blkdev_bszset(bdev, mode, argp);
diff --git a/block/partition-generic.c b/block/partition-generic.c
index 5d8701941054..2c6ae2aed2c4 100644
--- a/block/partition-generic.c
+++ b/block/partition-generic.c
@@ -566,8 +566,8 @@ static struct page *read_pagecache_sector(struct block_device *bdev, sector_t n)
{
struct address_space *mapping = bdev->bd_inode->i_mapping;

- return read_mapping_page(mapping, (pgoff_t)(n >> (PAGE_CACHE_SHIFT-9)),
- NULL);
+ return read_mapping_page(mapping, (pgoff_t)(n >> (PAGE_SHIFT-9)),
+ NULL);
}

unsigned char *read_dev_sector(struct block_device *bdev, sector_t n, Sector *p)
@@ -584,9 +584,9 @@ unsigned char *read_dev_sector(struct block_device *bdev, sector_t n, Sector *p)
if (PageError(page))
goto fail;
p->v = page;
- return (unsigned char *)page_address(page) + ((n & ((1 << (PAGE_CACHE_SHIFT - 9)) - 1)) << 9);
+ return (unsigned char *)page_address(page) + ((n & ((1 << (PAGE_SHIFT - 9)) - 1)) << 9);
fail:
- page_cache_release(page);
+ put_page(page);
}
p->v = NULL;
return NULL;
diff --git a/drivers/block/aoe/aoeblk.c b/drivers/block/aoe/aoeblk.c
index dd73e1ff1759..ec9d8610b25f 100644
--- a/drivers/block/aoe/aoeblk.c
+++ b/drivers/block/aoe/aoeblk.c
@@ -397,7 +397,7 @@ aoeblk_gdalloc(void *vp)
WARN_ON(d->flags & DEVFL_UP);
blk_queue_max_hw_sectors(q, BLK_DEF_MAX_SECTORS);
q->backing_dev_info.name = "aoe";
- q->backing_dev_info.ra_pages = READ_AHEAD / PAGE_CACHE_SIZE;
+ q->backing_dev_info.ra_pages = READ_AHEAD / PAGE_SIZE;
d->bufpool = mp;
d->blkq = gd->queue = q;
q->queuedata = d;
diff --git a/drivers/block/brd.c b/drivers/block/brd.c
index f7ecc287d733..51a071e32221 100644
--- a/drivers/block/brd.c
+++ b/drivers/block/brd.c
@@ -374,7 +374,7 @@ static int brd_rw_page(struct block_device *bdev, sector_t sector,
struct page *page, int rw)
{
struct brd_device *brd = bdev->bd_disk->private_data;
- int err = brd_do_bvec(brd, page, PAGE_CACHE_SIZE, 0, rw, sector);
+ int err = brd_do_bvec(brd, page, PAGE_SIZE, 0, rw, sector);
page_endio(page, rw & WRITE, err);
return err;
}
diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index c227fd4cad75..7a1cf7eaa71d 100644
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -1327,8 +1327,8 @@ struct bm_extent {
#endif
#endif

-/* BIO_MAX_SIZE is 256 * PAGE_CACHE_SIZE,
- * so for typical PAGE_CACHE_SIZE of 4k, that is (1<<20) Byte.
+/* BIO_MAX_SIZE is 256 * PAGE_SIZE,
+ * so for typical PAGE_SIZE of 4k, that is (1<<20) Byte.
* Since we may live in a mixed-platform cluster,
* we limit us to a platform agnostic constant here for now.
* A followup commit may allow even bigger BIO sizes,
diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index 226eb0c9f0fb..1fd1dccebb6b 100644
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -1178,7 +1178,7 @@ static void drbd_setup_queue_param(struct drbd_device *device, struct drbd_backi
blk_queue_max_hw_sectors(q, max_hw_sectors);
/* This is the workaround for "bio would need to, but cannot, be split" */
blk_queue_max_segments(q, max_segments ? max_segments : BLK_MAX_SEGMENTS);
- blk_queue_segment_boundary(q, PAGE_CACHE_SIZE-1);
+ blk_queue_segment_boundary(q, PAGE_SIZE-1);

if (b) {
struct drbd_connection *connection = first_peer_device(device)->connection;
diff --git a/include/linux/backing-dev-defs.h b/include/linux/backing-dev-defs.h
index 1b4d69f68c33..3f103076d0bf 100644
--- a/include/linux/backing-dev-defs.h
+++ b/include/linux/backing-dev-defs.h
@@ -135,7 +135,7 @@ struct bdi_writeback {

struct backing_dev_info {
struct list_head bdi_list;
- unsigned long ra_pages; /* max readahead in PAGE_CACHE_SIZE units */
+ unsigned long ra_pages; /* max readahead in PAGE_SIZE units */
unsigned int capabilities; /* Device capabilities */
congested_fn *congested_fn; /* Function pointer if device is md/dm */
void *congested_data; /* Pointer to aux data for congested func */
diff --git a/include/linux/bio.h b/include/linux/bio.h
index 88bc64f00bb5..6b7481f62218 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -41,7 +41,7 @@
#endif

#define BIO_MAX_PAGES 256
-#define BIO_MAX_SIZE (BIO_MAX_PAGES << PAGE_CACHE_SHIFT)
+#define BIO_MAX_SIZE (BIO_MAX_PAGES << PAGE_SHIFT)
#define BIO_MAX_SECTORS (BIO_MAX_SIZE >> 9)

/*
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 7e5d7e018bea..669e419d6234 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1372,7 +1372,7 @@ unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);

static inline void put_dev_sector(Sector p)
{
- page_cache_release(p.v);
+ put_page(p.v);
}

static inline bool __bvec_gap_to_prev(struct request_queue *q,
--
2.7.0