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path: root/drivers/block/zram/zram_drv.c
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Diffstat (limited to 'drivers/block/zram/zram_drv.c')
-rw-r--r--drivers/block/zram/zram_drv.c104
1 files changed, 71 insertions, 33 deletions
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 3920ee45aa59..bd8bda386e02 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -44,15 +44,14 @@ static const char *default_compressor = "lzo";
static unsigned int num_devices = 1;
#define ZRAM_ATTR_RO(name) \
-static ssize_t zram_attr_##name##_show(struct device *d, \
+static ssize_t name##_show(struct device *d, \
struct device_attribute *attr, char *b) \
{ \
struct zram *zram = dev_to_zram(d); \
return scnprintf(b, PAGE_SIZE, "%llu\n", \
(u64)atomic64_read(&zram->stats.name)); \
} \
-static struct device_attribute dev_attr_##name = \
- __ATTR(name, S_IRUGO, zram_attr_##name##_show, NULL);
+static DEVICE_ATTR_RO(name);
static inline int init_done(struct zram *zram)
{
@@ -287,19 +286,18 @@ static inline int is_partial_io(struct bio_vec *bvec)
/*
* Check if request is within bounds and aligned on zram logical blocks.
*/
-static inline int valid_io_request(struct zram *zram, struct bio *bio)
+static inline int valid_io_request(struct zram *zram,
+ sector_t start, unsigned int size)
{
- u64 start, end, bound;
+ u64 end, bound;
/* unaligned request */
- if (unlikely(bio->bi_iter.bi_sector &
- (ZRAM_SECTOR_PER_LOGICAL_BLOCK - 1)))
+ if (unlikely(start & (ZRAM_SECTOR_PER_LOGICAL_BLOCK - 1)))
return 0;
- if (unlikely(bio->bi_iter.bi_size & (ZRAM_LOGICAL_BLOCK_SIZE - 1)))
+ if (unlikely(size & (ZRAM_LOGICAL_BLOCK_SIZE - 1)))
return 0;
- start = bio->bi_iter.bi_sector;
- end = start + (bio->bi_iter.bi_size >> SECTOR_SHIFT);
+ end = start + (size >> SECTOR_SHIFT);
bound = zram->disksize >> SECTOR_SHIFT;
/* out of range range */
if (unlikely(start >= bound || end > bound || start > end))
@@ -453,7 +451,7 @@ static int zram_decompress_page(struct zram *zram, char *mem, u32 index)
}
static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec,
- u32 index, int offset, struct bio *bio)
+ u32 index, int offset)
{
int ret;
struct page *page;
@@ -645,14 +643,13 @@ out:
}
static int zram_bvec_rw(struct zram *zram, struct bio_vec *bvec, u32 index,
- int offset, struct bio *bio)
+ int offset, int rw)
{
int ret;
- int rw = bio_data_dir(bio);
if (rw == READ) {
atomic64_inc(&zram->stats.num_reads);
- ret = zram_bvec_read(zram, bvec, index, offset, bio);
+ ret = zram_bvec_read(zram, bvec, index, offset);
} else {
atomic64_inc(&zram->stats.num_writes);
ret = zram_bvec_write(zram, bvec, index, offset);
@@ -853,7 +850,7 @@ out:
static void __zram_make_request(struct zram *zram, struct bio *bio)
{
- int offset;
+ int offset, rw;
u32 index;
struct bio_vec bvec;
struct bvec_iter iter;
@@ -868,6 +865,7 @@ static void __zram_make_request(struct zram *zram, struct bio *bio)
return;
}
+ rw = bio_data_dir(bio);
bio_for_each_segment(bvec, bio, iter) {
int max_transfer_size = PAGE_SIZE - offset;
@@ -882,15 +880,15 @@ static void __zram_make_request(struct zram *zram, struct bio *bio)
bv.bv_len = max_transfer_size;
bv.bv_offset = bvec.bv_offset;
- if (zram_bvec_rw(zram, &bv, index, offset, bio) < 0)
+ if (zram_bvec_rw(zram, &bv, index, offset, rw) < 0)
goto out;
bv.bv_len = bvec.bv_len - max_transfer_size;
bv.bv_offset += max_transfer_size;
- if (zram_bvec_rw(zram, &bv, index + 1, 0, bio) < 0)
+ if (zram_bvec_rw(zram, &bv, index + 1, 0, rw) < 0)
goto out;
} else
- if (zram_bvec_rw(zram, &bvec, index, offset, bio) < 0)
+ if (zram_bvec_rw(zram, &bvec, index, offset, rw) < 0)
goto out;
update_position(&index, &offset, &bvec);
@@ -915,7 +913,8 @@ static void zram_make_request(struct request_queue *queue, struct bio *bio)
if (unlikely(!init_done(zram)))
goto error;
- if (!valid_io_request(zram, bio)) {
+ if (!valid_io_request(zram, bio->bi_iter.bi_sector,
+ bio->bi_iter.bi_size)) {
atomic64_inc(&zram->stats.invalid_io);
goto error;
}
@@ -945,25 +944,64 @@ static void zram_slot_free_notify(struct block_device *bdev,
atomic64_inc(&zram->stats.notify_free);
}
+static int zram_rw_page(struct block_device *bdev, sector_t sector,
+ struct page *page, int rw)
+{
+ int offset, err;
+ u32 index;
+ struct zram *zram;
+ struct bio_vec bv;
+
+ zram = bdev->bd_disk->private_data;
+ if (!valid_io_request(zram, sector, PAGE_SIZE)) {
+ atomic64_inc(&zram->stats.invalid_io);
+ return -EINVAL;
+ }
+
+ down_read(&zram->init_lock);
+ if (unlikely(!init_done(zram))) {
+ err = -EIO;
+ goto out_unlock;
+ }
+
+ index = sector >> SECTORS_PER_PAGE_SHIFT;
+ offset = sector & (SECTORS_PER_PAGE - 1) << SECTOR_SHIFT;
+
+ bv.bv_page = page;
+ bv.bv_len = PAGE_SIZE;
+ bv.bv_offset = 0;
+
+ err = zram_bvec_rw(zram, &bv, index, offset, rw);
+out_unlock:
+ up_read(&zram->init_lock);
+ /*
+ * If I/O fails, just return error(ie, non-zero) without
+ * calling page_endio.
+ * It causes resubmit the I/O with bio request by upper functions
+ * of rw_page(e.g., swap_readpage, __swap_writepage) and
+ * bio->bi_end_io does things to handle the error
+ * (e.g., SetPageError, set_page_dirty and extra works).
+ */
+ if (err == 0)
+ page_endio(page, rw, 0);
+ return err;
+}
+
static const struct block_device_operations zram_devops = {
.swap_slot_free_notify = zram_slot_free_notify,
+ .rw_page = zram_rw_page,
.owner = THIS_MODULE
};
-static DEVICE_ATTR(disksize, S_IRUGO | S_IWUSR,
- disksize_show, disksize_store);
-static DEVICE_ATTR(initstate, S_IRUGO, initstate_show, NULL);
-static DEVICE_ATTR(reset, S_IWUSR, NULL, reset_store);
-static DEVICE_ATTR(orig_data_size, S_IRUGO, orig_data_size_show, NULL);
-static DEVICE_ATTR(mem_used_total, S_IRUGO, mem_used_total_show, NULL);
-static DEVICE_ATTR(mem_limit, S_IRUGO | S_IWUSR, mem_limit_show,
- mem_limit_store);
-static DEVICE_ATTR(mem_used_max, S_IRUGO | S_IWUSR, mem_used_max_show,
- mem_used_max_store);
-static DEVICE_ATTR(max_comp_streams, S_IRUGO | S_IWUSR,
- max_comp_streams_show, max_comp_streams_store);
-static DEVICE_ATTR(comp_algorithm, S_IRUGO | S_IWUSR,
- comp_algorithm_show, comp_algorithm_store);
+static DEVICE_ATTR_RW(disksize);
+static DEVICE_ATTR_RO(initstate);
+static DEVICE_ATTR_WO(reset);
+static DEVICE_ATTR_RO(orig_data_size);
+static DEVICE_ATTR_RO(mem_used_total);
+static DEVICE_ATTR_RW(mem_limit);
+static DEVICE_ATTR_RW(mem_used_max);
+static DEVICE_ATTR_RW(max_comp_streams);
+static DEVICE_ATTR_RW(comp_algorithm);
ZRAM_ATTR_RO(num_reads);
ZRAM_ATTR_RO(num_writes);