https://github.com/torvalds/linux
Revision a51139fdbcecd208b96d1b8038b7a9eea9455acc authored by Shawn Guo on 25 February 2015, 14:53:32 UTC, committed by Stephen Boyd on 11 March 2015, 23:00:20 UTC
Since commit 035a61c314eb ("clk: Make clk API return per-user struct clk
instances"), clk API users can no longer check if two struct clk
pointers are pointing to the same hardware clock, i.e. struct clk_hw, by
simply comparing two pointers. That's because with the per-user clk
change, a brand new struct clk is created whenever clients try to look
up the clock by calling clk_get() or sister functions like clk_get_sys()
and of_clk_get(). This changes the original behavior where the struct
clk is only created for once when clock driver registers the clock to
CCF in the first place. The net change here is before commit
035a61c314eb the struct clk pointer is unique for given hardware
clock, while after the commit the pointers returned by clk lookup calls
become different for the same hardware clock.
That said, the struct clk pointer comparing in the code doesn't work any
more. Call helper function clk_is_match() instead to fix the problem.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
1 parent 3d3801e
Tip revision: a51139fdbcecd208b96d1b8038b7a9eea9455acc authored by Shawn Guo on 25 February 2015, 14:53:32 UTC
ARM: imx: fix struct clk pointer comparing
ARM: imx: fix struct clk pointer comparing
Tip revision: a51139f
blk-lib.c
/*
* Functions related to generic helpers functions
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/bio.h>
#include <linux/blkdev.h>
#include <linux/scatterlist.h>
#include "blk.h"
struct bio_batch {
atomic_t done;
unsigned long flags;
struct completion *wait;
};
static void bio_batch_end_io(struct bio *bio, int err)
{
struct bio_batch *bb = bio->bi_private;
if (err && (err != -EOPNOTSUPP))
clear_bit(BIO_UPTODATE, &bb->flags);
if (atomic_dec_and_test(&bb->done))
complete(bb->wait);
bio_put(bio);
}
/**
* blkdev_issue_discard - queue a discard
* @bdev: blockdev to issue discard for
* @sector: start sector
* @nr_sects: number of sectors to discard
* @gfp_mask: memory allocation flags (for bio_alloc)
* @flags: BLKDEV_IFL_* flags to control behaviour
*
* Description:
* Issue a discard request for the sectors in question.
*/
int blkdev_issue_discard(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp_mask, unsigned long flags)
{
DECLARE_COMPLETION_ONSTACK(wait);
struct request_queue *q = bdev_get_queue(bdev);
int type = REQ_WRITE | REQ_DISCARD;
unsigned int max_discard_sectors, granularity;
int alignment;
struct bio_batch bb;
struct bio *bio;
int ret = 0;
struct blk_plug plug;
if (!q)
return -ENXIO;
if (!blk_queue_discard(q))
return -EOPNOTSUPP;
/* Zero-sector (unknown) and one-sector granularities are the same. */
granularity = max(q->limits.discard_granularity >> 9, 1U);
alignment = (bdev_discard_alignment(bdev) >> 9) % granularity;
/*
* Ensure that max_discard_sectors is of the proper
* granularity, so that requests stay aligned after a split.
*/
max_discard_sectors = min(q->limits.max_discard_sectors, UINT_MAX >> 9);
max_discard_sectors -= max_discard_sectors % granularity;
if (unlikely(!max_discard_sectors)) {
/* Avoid infinite loop below. Being cautious never hurts. */
return -EOPNOTSUPP;
}
if (flags & BLKDEV_DISCARD_SECURE) {
if (!blk_queue_secdiscard(q))
return -EOPNOTSUPP;
type |= REQ_SECURE;
}
atomic_set(&bb.done, 1);
bb.flags = 1 << BIO_UPTODATE;
bb.wait = &wait;
blk_start_plug(&plug);
while (nr_sects) {
unsigned int req_sects;
sector_t end_sect, tmp;
bio = bio_alloc(gfp_mask, 1);
if (!bio) {
ret = -ENOMEM;
break;
}
req_sects = min_t(sector_t, nr_sects, max_discard_sectors);
/*
* If splitting a request, and the next starting sector would be
* misaligned, stop the discard at the previous aligned sector.
*/
end_sect = sector + req_sects;
tmp = end_sect;
if (req_sects < nr_sects &&
sector_div(tmp, granularity) != alignment) {
end_sect = end_sect - alignment;
sector_div(end_sect, granularity);
end_sect = end_sect * granularity + alignment;
req_sects = end_sect - sector;
}
bio->bi_iter.bi_sector = sector;
bio->bi_end_io = bio_batch_end_io;
bio->bi_bdev = bdev;
bio->bi_private = &bb;
bio->bi_iter.bi_size = req_sects << 9;
nr_sects -= req_sects;
sector = end_sect;
atomic_inc(&bb.done);
submit_bio(type, bio);
/*
* We can loop for a long time in here, if someone does
* full device discards (like mkfs). Be nice and allow
* us to schedule out to avoid softlocking if preempt
* is disabled.
*/
cond_resched();
}
blk_finish_plug(&plug);
/* Wait for bios in-flight */
if (!atomic_dec_and_test(&bb.done))
wait_for_completion_io(&wait);
if (!test_bit(BIO_UPTODATE, &bb.flags))
ret = -EIO;
return ret;
}
EXPORT_SYMBOL(blkdev_issue_discard);
/**
* blkdev_issue_write_same - queue a write same operation
* @bdev: target blockdev
* @sector: start sector
* @nr_sects: number of sectors to write
* @gfp_mask: memory allocation flags (for bio_alloc)
* @page: page containing data to write
*
* Description:
* Issue a write same request for the sectors in question.
*/
int blkdev_issue_write_same(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp_mask,
struct page *page)
{
DECLARE_COMPLETION_ONSTACK(wait);
struct request_queue *q = bdev_get_queue(bdev);
unsigned int max_write_same_sectors;
struct bio_batch bb;
struct bio *bio;
int ret = 0;
if (!q)
return -ENXIO;
max_write_same_sectors = q->limits.max_write_same_sectors;
if (max_write_same_sectors == 0)
return -EOPNOTSUPP;
atomic_set(&bb.done, 1);
bb.flags = 1 << BIO_UPTODATE;
bb.wait = &wait;
while (nr_sects) {
bio = bio_alloc(gfp_mask, 1);
if (!bio) {
ret = -ENOMEM;
break;
}
bio->bi_iter.bi_sector = sector;
bio->bi_end_io = bio_batch_end_io;
bio->bi_bdev = bdev;
bio->bi_private = &bb;
bio->bi_vcnt = 1;
bio->bi_io_vec->bv_page = page;
bio->bi_io_vec->bv_offset = 0;
bio->bi_io_vec->bv_len = bdev_logical_block_size(bdev);
if (nr_sects > max_write_same_sectors) {
bio->bi_iter.bi_size = max_write_same_sectors << 9;
nr_sects -= max_write_same_sectors;
sector += max_write_same_sectors;
} else {
bio->bi_iter.bi_size = nr_sects << 9;
nr_sects = 0;
}
atomic_inc(&bb.done);
submit_bio(REQ_WRITE | REQ_WRITE_SAME, bio);
}
/* Wait for bios in-flight */
if (!atomic_dec_and_test(&bb.done))
wait_for_completion_io(&wait);
if (!test_bit(BIO_UPTODATE, &bb.flags))
ret = -ENOTSUPP;
return ret;
}
EXPORT_SYMBOL(blkdev_issue_write_same);
/**
* blkdev_issue_zeroout - generate number of zero filed write bios
* @bdev: blockdev to issue
* @sector: start sector
* @nr_sects: number of sectors to write
* @gfp_mask: memory allocation flags (for bio_alloc)
*
* Description:
* Generate and issue number of bios with zerofiled pages.
*/
static int __blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp_mask)
{
int ret;
struct bio *bio;
struct bio_batch bb;
unsigned int sz;
DECLARE_COMPLETION_ONSTACK(wait);
atomic_set(&bb.done, 1);
bb.flags = 1 << BIO_UPTODATE;
bb.wait = &wait;
ret = 0;
while (nr_sects != 0) {
bio = bio_alloc(gfp_mask,
min(nr_sects, (sector_t)BIO_MAX_PAGES));
if (!bio) {
ret = -ENOMEM;
break;
}
bio->bi_iter.bi_sector = sector;
bio->bi_bdev = bdev;
bio->bi_end_io = bio_batch_end_io;
bio->bi_private = &bb;
while (nr_sects != 0) {
sz = min((sector_t) PAGE_SIZE >> 9 , nr_sects);
ret = bio_add_page(bio, ZERO_PAGE(0), sz << 9, 0);
nr_sects -= ret >> 9;
sector += ret >> 9;
if (ret < (sz << 9))
break;
}
ret = 0;
atomic_inc(&bb.done);
submit_bio(WRITE, bio);
}
/* Wait for bios in-flight */
if (!atomic_dec_and_test(&bb.done))
wait_for_completion_io(&wait);
if (!test_bit(BIO_UPTODATE, &bb.flags))
/* One of bios in the batch was completed with error.*/
ret = -EIO;
return ret;
}
/**
* blkdev_issue_zeroout - zero-fill a block range
* @bdev: blockdev to write
* @sector: start sector
* @nr_sects: number of sectors to write
* @gfp_mask: memory allocation flags (for bio_alloc)
* @discard: whether to discard the block range
*
* Description:
* Zero-fill a block range. If the discard flag is set and the block
* device guarantees that subsequent READ operations to the block range
* in question will return zeroes, the blocks will be discarded. Should
* the discard request fail, if the discard flag is not set, or if
* discard_zeroes_data is not supported, this function will resort to
* zeroing the blocks manually, thus provisioning (allocating,
* anchoring) them. If the block device supports the WRITE SAME command
* blkdev_issue_zeroout() will use it to optimize the process of
* clearing the block range. Otherwise the zeroing will be performed
* using regular WRITE calls.
*/
int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
sector_t nr_sects, gfp_t gfp_mask, bool discard)
{
struct request_queue *q = bdev_get_queue(bdev);
if (discard && blk_queue_discard(q) && q->limits.discard_zeroes_data &&
blkdev_issue_discard(bdev, sector, nr_sects, gfp_mask, 0) == 0)
return 0;
if (bdev_write_same(bdev) &&
blkdev_issue_write_same(bdev, sector, nr_sects, gfp_mask,
ZERO_PAGE(0)) == 0)
return 0;
return __blkdev_issue_zeroout(bdev, sector, nr_sects, gfp_mask);
}
EXPORT_SYMBOL(blkdev_issue_zeroout);
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