diff options
| -rw-r--r-- | drivers/block/zram/zram_drv.c | 639 |
1 files changed, 319 insertions, 320 deletions
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index 3e2e152ac..c1eed5427 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -71,33 +71,117 @@ static inline struct zram *dev_to_zram(struct device *dev) return (struct zram *)dev_to_disk(dev)->private_data; } -static ssize_t compact_store(struct device *dev, - struct device_attribute *attr, const char *buf, size_t len) +/* flag operations needs meta->tb_lock */ +static int zram_test_flag(struct zram_meta *meta, u32 index, + enum zram_pageflags flag) { - unsigned long nr_migrated; - struct zram *zram = dev_to_zram(dev); - struct zram_meta *meta; + return meta->table[index].value & BIT(flag); +} - down_read(&zram->init_lock); - if (!init_done(zram)) { - up_read(&zram->init_lock); - return -EINVAL; - } +static void zram_set_flag(struct zram_meta *meta, u32 index, + enum zram_pageflags flag) +{ + meta->table[index].value |= BIT(flag); +} - meta = zram->meta; - nr_migrated = zs_compact(meta->mem_pool); - atomic64_add(nr_migrated, &zram->stats.num_migrated); - up_read(&zram->init_lock); +static void zram_clear_flag(struct zram_meta *meta, u32 index, + enum zram_pageflags flag) +{ + meta->table[index].value &= ~BIT(flag); +} - return len; +static size_t zram_get_obj_size(struct zram_meta *meta, u32 index) +{ + return meta->table[index].value & (BIT(ZRAM_FLAG_SHIFT) - 1); } -static ssize_t disksize_show(struct device *dev, - struct device_attribute *attr, char *buf) +static void zram_set_obj_size(struct zram_meta *meta, + u32 index, size_t size) { - struct zram *zram = dev_to_zram(dev); + unsigned long flags = meta->table[index].value >> ZRAM_FLAG_SHIFT; - return scnprintf(buf, PAGE_SIZE, "%llu\n", zram->disksize); + meta->table[index].value = (flags << ZRAM_FLAG_SHIFT) | size; +} + +static inline int is_partial_io(struct bio_vec *bvec) +{ + return bvec->bv_len != PAGE_SIZE; +} + +/* + * Check if request is within bounds and aligned on zram logical blocks. + */ +static inline int valid_io_request(struct zram *zram, + sector_t start, unsigned int size) +{ + u64 end, bound; + + /* unaligned request */ + if (unlikely(start & (ZRAM_SECTOR_PER_LOGICAL_BLOCK - 1))) + return 0; + if (unlikely(size & (ZRAM_LOGICAL_BLOCK_SIZE - 1))) + return 0; + + end = start + (size >> SECTOR_SHIFT); + bound = zram->disksize >> SECTOR_SHIFT; + /* out of range range */ + if (unlikely(start >= bound || end > bound || start > end)) + return 0; + + /* I/O request is valid */ + return 1; +} + +static void update_position(u32 *index, int *offset, struct bio_vec *bvec) +{ + if (*offset + bvec->bv_len >= PAGE_SIZE) + (*index)++; + *offset = (*offset + bvec->bv_len) % PAGE_SIZE; +} + +static inline void update_used_max(struct zram *zram, + const unsigned long pages) +{ + unsigned long old_max, cur_max; + + old_max = atomic_long_read(&zram->stats.max_used_pages); + + do { + cur_max = old_max; + if (pages > cur_max) + old_max = atomic_long_cmpxchg( + &zram->stats.max_used_pages, cur_max, pages); + } while (old_max != cur_max); +} + +static int page_zero_filled(void *ptr) +{ + unsigned int pos; + unsigned long *page; + + page = (unsigned long *)ptr; + + for (pos = 0; pos != PAGE_SIZE / sizeof(*page); pos++) { + if (page[pos]) + return 0; + } + + return 1; +} + +static void handle_zero_page(struct bio_vec *bvec) +{ + struct page *page = bvec->bv_page; + void *user_mem; + + user_mem = kmap_atomic(page); + if (is_partial_io(bvec)) + memset(user_mem + bvec->bv_offset, 0, bvec->bv_len); + else + clear_page(user_mem); + kunmap_atomic(user_mem); + + flush_dcache_page(page); } static ssize_t initstate_show(struct device *dev, @@ -113,6 +197,14 @@ static ssize_t initstate_show(struct device *dev, return scnprintf(buf, PAGE_SIZE, "%u\n", val); } +static ssize_t disksize_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct zram *zram = dev_to_zram(dev); + + return scnprintf(buf, PAGE_SIZE, "%llu\n", zram->disksize); +} + static ssize_t orig_data_size_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -140,19 +232,6 @@ static ssize_t mem_used_total_show(struct device *dev, return scnprintf(buf, PAGE_SIZE, "%llu\n", val << PAGE_SHIFT); } -static ssize_t max_comp_streams_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - int val; - struct zram *zram = dev_to_zram(dev); - - down_read(&zram->init_lock); - val = zram->max_comp_streams; - up_read(&zram->init_lock); - - return scnprintf(buf, PAGE_SIZE, "%d\n", val); -} - static ssize_t mem_limit_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -222,6 +301,19 @@ static ssize_t mem_used_max_store(struct device *dev, return len; } +static ssize_t max_comp_streams_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + int val; + struct zram *zram = dev_to_zram(dev); + + down_read(&zram->init_lock); + val = zram->max_comp_streams; + up_read(&zram->init_lock); + + return scnprintf(buf, PAGE_SIZE, "%d\n", val); +} + static ssize_t max_comp_streams_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { @@ -279,65 +371,95 @@ static ssize_t comp_algorithm_store(struct device *dev, return len; } -/* flag operations needs meta->tb_lock */ -static int zram_test_flag(struct zram_meta *meta, u32 index, - enum zram_pageflags flag) +static ssize_t compact_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t len) { - return meta->table[index].value & BIT(flag); -} + unsigned long nr_migrated; + struct zram *zram = dev_to_zram(dev); + struct zram_meta *meta; -static void zram_set_flag(struct zram_meta *meta, u32 index, - enum zram_pageflags flag) -{ - meta->table[index].value |= BIT(flag); -} + down_read(&zram->init_lock); + if (!init_done(zram)) { + up_read(&zram->init_lock); + return -EINVAL; + } -static void zram_clear_flag(struct zram_meta *meta, u32 index, - enum zram_pageflags flag) -{ - meta->table[index].value &= ~BIT(flag); + meta = zram->meta; + nr_migrated = zs_compact(meta->mem_pool); + atomic64_add(nr_migrated, &zram->stats.num_migrated); + up_read(&zram->init_lock); + + return len; } -static size_t zram_get_obj_size(struct zram_meta *meta, u32 index) +static ssize_t io_stat_show(struct device *dev, + struct device_attribute *attr, char *buf) { - return meta->table[index].value & (BIT(ZRAM_FLAG_SHIFT) - 1); + struct zram *zram = dev_to_zram(dev); + ssize_t ret; + + down_read(&zram->init_lock); + ret = scnprintf(buf, PAGE_SIZE, + "%8llu %8llu %8llu %8llu\n", + (u64)atomic64_read(&zram->stats.failed_reads), + (u64)atomic64_read(&zram->stats.failed_writes), + (u64)atomic64_read(&zram->stats.invalid_io), + (u64)atomic64_read(&zram->stats.notify_free)); + up_read(&zram->init_lock); + + return ret; } -static void zram_set_obj_size(struct zram_meta *meta, - u32 index, size_t size) +static ssize_t mm_stat_show(struct device *dev, + struct device_attribute *attr, char *buf) { - unsigned long flags = meta->table[index].value >> ZRAM_FLAG_SHIFT; + struct zram *zram = dev_to_zram(dev); + u64 orig_size, mem_used = 0; + long max_used; + ssize_t ret; - meta->table[index].value = (flags << ZRAM_FLAG_SHIFT) | size; + down_read(&zram->init_lock); + if (init_done(zram)) + mem_used = zs_get_total_pages(zram->meta->mem_pool); + + orig_size = atomic64_read(&zram->stats.pages_stored); + max_used = atomic_long_read(&zram->stats.max_used_pages); + + ret = scnprintf(buf, PAGE_SIZE, + "%8llu %8llu %8llu %8lu %8ld %8llu %8llu\n", + orig_size << PAGE_SHIFT, + (u64)atomic64_read(&zram->stats.compr_data_size), + mem_used << PAGE_SHIFT, + zram->limit_pages << PAGE_SHIFT, + max_used << PAGE_SHIFT, + (u64)atomic64_read(&zram->stats.zero_pages), + (u64)atomic64_read(&zram->stats.num_migrated)); + up_read(&zram->init_lock); + + return ret; } -static inline int is_partial_io(struct bio_vec *bvec) +static DEVICE_ATTR_RO(io_stat); +static DEVICE_ATTR_RO(mm_stat); +ZRAM_ATTR_RO(num_reads); +ZRAM_ATTR_RO(num_writes); +ZRAM_ATTR_RO(failed_reads); +ZRAM_ATTR_RO(failed_writes); +ZRAM_ATTR_RO(invalid_io); +ZRAM_ATTR_RO(notify_free); +ZRAM_ATTR_RO(zero_pages); +ZRAM_ATTR_RO(compr_data_size); + +static inline bool zram_meta_get(struct zram *zram) { - return bvec->bv_len != PAGE_SIZE; + if (atomic_inc_not_zero(&zram->refcount)) + return true; + return false; } -/* - * Check if request is within bounds and aligned on zram logical blocks. - */ -static inline int valid_io_request(struct zram *zram, - sector_t start, unsigned int size) +static inline void zram_meta_put(struct zram *zram) { - u64 end, bound; - - /* unaligned request */ - if (unlikely(start & (ZRAM_SECTOR_PER_LOGICAL_BLOCK - 1))) - return 0; - if (unlikely(size & (ZRAM_LOGICAL_BLOCK_SIZE - 1))) - return 0; - - end = start + (size >> SECTOR_SHIFT); - bound = zram->disksize >> SECTOR_SHIFT; - /* out of range range */ - if (unlikely(start >= bound || end > bound || start > end)) - return 0; - - /* I/O request is valid */ - return 1; + atomic_dec(&zram->refcount); } static void zram_meta_free(struct zram_meta *meta, u64 disksize) @@ -391,56 +513,6 @@ out_error: return NULL; } -static inline bool zram_meta_get(struct zram *zram) -{ - if (atomic_inc_not_zero(&zram->refcount)) - return true; - return false; -} - -static inline void zram_meta_put(struct zram *zram) -{ - atomic_dec(&zram->refcount); -} - -static void update_position(u32 *index, int *offset, struct bio_vec *bvec) -{ - if (*offset + bvec->bv_len >= PAGE_SIZE) - (*index)++; - *offset = (*offset + bvec->bv_len) % PAGE_SIZE; -} - -static int page_zero_filled(void *ptr) -{ - unsigned int pos; - unsigned long *page; - - page = (unsigned long *)ptr; - - for (pos = 0; pos != PAGE_SIZE / sizeof(*page); pos++) { - if (page[pos]) - return 0; - } - - return 1; -} - -static void handle_zero_page(struct bio_vec *bvec) -{ - struct page *page = bvec->bv_page; - void *user_mem; - - user_mem = kmap_atomic(page); - if (is_partial_io(bvec)) - memset(user_mem + bvec->bv_offset, 0, bvec->bv_len); - else - clear_page(user_mem); - kunmap_atomic(user_mem); - - flush_dcache_page(page); -} - - /* * To protect concurrent access to the same index entry, * caller should hold this table index entry's bit_spinlock to @@ -558,21 +630,6 @@ out_cleanup: return ret; } -static inline void update_used_max(struct zram *zram, - const unsigned long pages) -{ - unsigned long old_max, cur_max; - - old_max = atomic_long_read(&zram->stats.max_used_pages); - - do { - cur_max = old_max; - if (pages > cur_max) - old_max = atomic_long_cmpxchg( - &zram->stats.max_used_pages, cur_max, pages); - } while (old_max != cur_max); -} - static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index, int offset) { @@ -700,35 +757,6 @@ out: return ret; } -static int zram_bvec_rw(struct zram *zram, struct bio_vec *bvec, u32 index, - int offset, int rw) -{ - unsigned long start_time = jiffies; - int ret; - - generic_start_io_acct(rw, bvec->bv_len >> SECTOR_SHIFT, - &zram->disk->part0); - - if (rw == READ) { - atomic64_inc(&zram->stats.num_reads); - ret = zram_bvec_read(zram, bvec, index, offset); - } else { - atomic64_inc(&zram->stats.num_writes); - ret = zram_bvec_write(zram, bvec, index, offset); - } - - generic_end_io_acct(rw, &zram->disk->part0, start_time); - - if (unlikely(ret)) { - if (rw == READ) - atomic64_inc(&zram->stats.failed_reads); - else - atomic64_inc(&zram->stats.failed_writes); - } - - return ret; -} - /* * zram_bio_discard - handler on discard request * @index: physical block index in PAGE_SIZE units @@ -768,6 +796,128 @@ static void zram_bio_discard(struct zram *zram, u32 index, } } +static int zram_bvec_rw(struct zram *zram, struct bio_vec *bvec, u32 index, + int offset, int rw) +{ + unsigned long start_time = jiffies; + int ret; + + generic_start_io_acct(rw, bvec->bv_len >> SECTOR_SHIFT, + &zram->disk->part0); + + if (rw == READ) { + atomic64_inc(&zram->stats.num_reads); + ret = zram_bvec_read(zram, bvec, index, offset); + } else { + atomic64_inc(&zram->stats.num_writes); + ret = zram_bvec_write(zram, bvec, index, offset); + } + + generic_end_io_acct(rw, &zram->disk->part0, start_time); + + if (unlikely(ret)) { + if (rw == READ) + atomic64_inc(&zram->stats.failed_reads); + else + atomic64_inc(&zram->stats.failed_writes); + } + + return ret; +} + +static void __zram_make_request(struct zram *zram, struct bio *bio) +{ + int i, offset, rw; + u32 index; + struct bio_vec *bvec; + + index = bio->bi_sector >> SECTORS_PER_PAGE_SHIFT; + offset = (bio->bi_sector & + (SECTORS_PER_PAGE - 1)) << SECTOR_SHIFT; + + if (unlikely(bio->bi_rw & REQ_DISCARD)) { + zram_bio_discard(zram, index, offset, bio); + bio_endio(bio, 0); + return; + } + + rw = bio_data_dir(bio); + bio_for_each_segment(bvec, bio, i) { + int max_transfer_size = PAGE_SIZE - offset; + + if (bvec->bv_len > max_transfer_size) { + /* + * zram_bvec_rw() can only make operation on a single + * zram page. Split the bio vector. + */ + struct bio_vec bv; + + bv.bv_page = bvec->bv_page; + bv.bv_len = max_transfer_size; + bv.bv_offset = bvec->bv_offset; + + 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, rw) < 0) + goto out; + } else + if (zram_bvec_rw(zram, bvec, index, offset, rw) < 0) + goto out; + + update_position(&index, &offset, bvec); + } + + set_bit(BIO_UPTODATE, &bio->bi_flags); + bio_endio(bio, 0); + return; + +out: + bio_io_error(bio); +} + +/* + * Handler function for all zram I/O requests. + */ +static void zram_make_request(struct request_queue *queue, struct bio *bio) +{ + struct zram *zram = queue->queuedata; + + if (unlikely(!zram_meta_get(zram))) + goto error; + + if (!valid_io_request(zram, bio->bi_sector, + bio->bi_size)) { + atomic64_inc(&zram->stats.invalid_io); + goto put_zram; + } + + __zram_make_request(zram, bio); + zram_meta_put(zram); + return; +put_zram: + zram_meta_put(zram); +error: + bio_io_error(bio); +} + +static void zram_slot_free_notify(struct block_device *bdev, + unsigned long index) +{ + struct zram *zram; + struct zram_meta *meta; + + zram = bdev->bd_disk->private_data; + meta = zram->meta; + + bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value); + zram_free_page(zram, index); + bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value); + atomic64_inc(&zram->stats.notify_free); +} + static void zram_reset_device(struct zram *zram) { struct zram_meta *meta; @@ -916,99 +1066,6 @@ out: return ret; } -static void __zram_make_request(struct zram *zram, struct bio *bio) -{ - int i, offset, rw; - u32 index; - struct bio_vec *bvec; - - index = bio->bi_sector >> SECTORS_PER_PAGE_SHIFT; - offset = (bio->bi_sector & - (SECTORS_PER_PAGE - 1)) << SECTOR_SHIFT; - - if (unlikely(bio->bi_rw & REQ_DISCARD)) { - zram_bio_discard(zram, index, offset, bio); - bio_endio(bio, 0); - return; - } - - rw = bio_data_dir(bio); - bio_for_each_segment(bvec, bio, i) { - int max_transfer_size = PAGE_SIZE - offset; - - if (bvec->bv_len > max_transfer_size) { - /* - * zram_bvec_rw() can only make operation on a single - * zram page. Split the bio vector. - */ - struct bio_vec bv; - - bv.bv_page = bvec->bv_page; - bv.bv_len = max_transfer_size; - bv.bv_offset = bvec->bv_offset; - - 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, rw) < 0) - goto out; - } else - if (zram_bvec_rw(zram, bvec, index, offset, rw) < 0) - goto out; - - update_position(&index, &offset, bvec); - } - - set_bit(BIO_UPTODATE, &bio->bi_flags); - bio_endio(bio, 0); - return; - -out: - bio_io_error(bio); -} - -/* - * Handler function for all zram I/O requests. - */ -static void zram_make_request(struct request_queue *queue, struct bio *bio) -{ - struct zram *zram = queue->queuedata; - - if (unlikely(!zram_meta_get(zram))) - goto error; - - if (!valid_io_request(zram, bio->bi_sector, - bio->bi_size)) { - atomic64_inc(&zram->stats.invalid_io); - goto put_zram; - } - - __zram_make_request(zram, bio); - zram_meta_put(zram); - return; -put_zram: - zram_meta_put(zram); -error: - bio_io_error(bio); -} - -static void zram_slot_free_notify(struct block_device *bdev, - unsigned long index) -{ - struct zram *zram; - struct zram_meta *meta; - - zram = bdev->bd_disk->private_data; - meta = zram->meta; - - bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value); - zram_free_page(zram, index); - bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value); - atomic64_inc(&zram->stats.notify_free); -} - static const struct block_device_operations zram_devops = { .swap_slot_free_notify = zram_slot_free_notify, .owner = THIS_MODULE @@ -1025,64 +1082,6 @@ static DEVICE_ATTR_RW(mem_used_max); static DEVICE_ATTR_RW(max_comp_streams); static DEVICE_ATTR_RW(comp_algorithm); -static ssize_t io_stat_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct zram *zram = dev_to_zram(dev); - ssize_t ret; - - down_read(&zram->init_lock); - ret = scnprintf(buf, PAGE_SIZE, - "%8llu %8llu %8llu %8llu\n", - (u64)atomic64_read(&zram->stats.failed_reads), - (u64)atomic64_read(&zram->stats.failed_writes), - (u64)atomic64_read(&zram->stats.invalid_io), - (u64)atomic64_read(&zram->stats.notify_free)); - up_read(&zram->init_lock); - - return ret; -} - -static ssize_t mm_stat_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - struct zram *zram = dev_to_zram(dev); - u64 orig_size, mem_used = 0; - long max_used; - ssize_t ret; - - down_read(&zram->init_lock); - if (init_done(zram)) - mem_used = zs_get_total_pages(zram->meta->mem_pool); - - orig_size = atomic64_read(&zram->stats.pages_stored); - max_used = atomic_long_read(&zram->stats.max_used_pages); - - ret = scnprintf(buf, PAGE_SIZE, - "%8llu %8llu %8llu %8lu %8ld %8llu %8llu\n", - orig_size << PAGE_SHIFT, - (u64)atomic64_read(&zram->stats.compr_data_size), - mem_used << PAGE_SHIFT, - zram->limit_pages << PAGE_SHIFT, - max_used << PAGE_SHIFT, - (u64)atomic64_read(&zram->stats.zero_pages), - (u64)atomic64_read(&zram->stats.num_migrated)); - up_read(&zram->init_lock); - - return ret; -} - -static DEVICE_ATTR_RO(io_stat); -static DEVICE_ATTR_RO(mm_stat); -ZRAM_ATTR_RO(num_reads); -ZRAM_ATTR_RO(num_writes); -ZRAM_ATTR_RO(failed_reads); -ZRAM_ATTR_RO(failed_writes); -ZRAM_ATTR_RO(invalid_io); -ZRAM_ATTR_RO(notify_free); -ZRAM_ATTR_RO(zero_pages); -ZRAM_ATTR_RO(compr_data_size); - static struct attribute *zram_disk_attrs[] = { &dev_attr_disksize.attr, &dev_attr_initstate.attr, |