From fd45af53e220b2fe13a5e8db88c5e92bc3296754 Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Tue, 11 Apr 2023 19:14:56 +0200
Subject: [PATCH] zram: pass a page to read_from_bdev
read_from_bdev always reads a whole page, so pass a page to it instead of
the bvec and remove the now pointless zram_bvec_read_from_bdev wrapper.
Link: https://lkml.kernel.org/r/20230411171459.567614-15-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Acked-by: Minchan Kim <minchan@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
drivers/block/zram/zram_drv.c | 43 +++++++++++++----------------------
1 file changed, 16 insertions(+), 27 deletions(-)
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 1a7fe75285e64..9a35bb0f1a03d 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -588,7 +588,7 @@ static void zram_page_end_io(struct bio *bio)
/*
* Returns 1 if the submission is successful.
*/
-static int read_from_bdev_async(struct zram *zram, struct bio_vec *bvec,
+static int read_from_bdev_async(struct zram *zram, struct page *page,
unsigned long entry, struct bio *parent)
{
struct bio *bio;
@@ -599,7 +599,7 @@ static int read_from_bdev_async(struct zram *zram, struct bio_vec *bvec,
return -ENOMEM;
bio->bi_iter.bi_sector = entry * (PAGE_SIZE >> 9);
- if (!bio_add_page(bio, bvec->bv_page, bvec->bv_len, bvec->bv_offset)) {
+ if (!bio_add_page(bio, page, PAGE_SIZE, 0)) {
bio_put(bio);
return -EIO;
}
@@ -795,7 +795,7 @@ struct zram_work {
struct zram *zram;
unsigned long entry;
struct bio *bio;
- struct bio_vec bvec;
+ struct page *page;
};
static void zram_sync_read(struct work_struct *work)
@@ -805,7 +805,7 @@ static void zram_sync_read(struct work_struct *work)
unsigned long entry = zw->entry;
struct bio *bio = zw->bio;
- read_from_bdev_async(zram, &zw->bvec, entry, bio);
+ read_from_bdev_async(zram, zw->page, entry, bio);
}
/*
@@ -813,12 +813,12 @@ static void zram_sync_read(struct work_struct *work)
* chained IO with parent IO in same context, it's a deadlock. To avoid that,
* use a worker thread context.
*/
-static int read_from_bdev_sync(struct zram *zram, struct bio_vec *bvec,
+static int read_from_bdev_sync(struct zram *zram, struct page *page,
unsigned long entry, struct bio *bio)
{
struct zram_work work;
- work.bvec = *bvec;
+ work.page = page;
work.zram = zram;
work.entry = entry;
work.bio = bio;
@@ -831,20 +831,20 @@ static int read_from_bdev_sync(struct zram *zram, struct bio_vec *bvec,
return 1;
}
-static int read_from_bdev(struct zram *zram, struct bio_vec *bvec,
+static int read_from_bdev(struct zram *zram, struct page *page,
unsigned long entry, struct bio *parent, bool sync)
{
atomic64_inc(&zram->stats.bd_reads);
if (sync) {
if (WARN_ON_ONCE(!IS_ENABLED(ZRAM_PARTIAL_IO)))
return -EIO;
- return read_from_bdev_sync(zram, bvec, entry, parent);
+ return read_from_bdev_sync(zram, page, entry, parent);
}
- return read_from_bdev_async(zram, bvec, entry, parent);
+ return read_from_bdev_async(zram, page, entry, parent);
}
#else
static inline void reset_bdev(struct zram *zram) {};
-static int read_from_bdev(struct zram *zram, struct bio_vec *bvec,
+static int read_from_bdev(struct zram *zram, struct page *page,
unsigned long entry, struct bio *parent, bool sync)
{
return -EIO;
@@ -1328,20 +1328,6 @@ out:
~(1UL << ZRAM_LOCK | 1UL << ZRAM_UNDER_WB));
}
-/*
- * Reads a page from the writeback devices. Corresponding ZRAM slot
- * should be unlocked.
- */
-static int zram_bvec_read_from_bdev(struct zram *zram, struct page *page,
- u32 index, struct bio *bio, bool partial_io)
-{
- struct bio_vec bvec;
-
- bvec_set_page(&bvec, page, PAGE_SIZE, 0);
- return read_from_bdev(zram, &bvec, zram_get_element(zram, index), bio,
- partial_io);
-}
-
/*
* Reads (decompresses if needed) a page from zspool (zsmalloc).
* Corresponding ZRAM slot should be locked.
@@ -1402,11 +1388,14 @@ static int zram_read_page(struct zram *zram, struct page *page, u32 index,
ret = zram_read_from_zspool(zram, page, index);
zram_slot_unlock(zram, index);
} else {
- /* Slot should be unlocked before the function call */
+ /*
+ * The slot should be unlocked before reading from the backing
+ * device.
+ */
zram_slot_unlock(zram, index);
- ret = zram_bvec_read_from_bdev(zram, page, index, bio,
- partial_io);
+ ret = read_from_bdev(zram, page, zram_get_element(zram, index),
+ bio, partial_io);
}
/* Should NEVER happen. Return bio error if it does. */
--
2.30.2