diff options
Diffstat (limited to 'drivers/block')
-rw-r--r-- | drivers/block/zram/zram_drv.c | 104 | ||||
-rw-r--r-- | drivers/block/zram/zram_drv.h | 4 |
2 files changed, 73 insertions, 35 deletions
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index 3920ee4..bd8bda3 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); diff --git a/drivers/block/zram/zram_drv.h b/drivers/block/zram/zram_drv.h index c6ee271..b05a816 100644 --- a/drivers/block/zram/zram_drv.h +++ b/drivers/block/zram/zram_drv.h @@ -66,8 +66,8 @@ static const size_t max_zpage_size = PAGE_SIZE / 4 * 3; /* Flags for zram pages (table[page_no].value) */ enum zram_pageflags { /* Page consists entirely of zeros */ - ZRAM_ZERO = ZRAM_FLAG_SHIFT + 1, - ZRAM_ACCESS, /* page in now accessed */ + ZRAM_ZERO = ZRAM_FLAG_SHIFT, + ZRAM_ACCESS, /* page is now accessed */ __NR_ZRAM_PAGEFLAGS, }; |