diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/block/zram/zram_drv.c | 70 |
1 files changed, 30 insertions, 40 deletions
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c index 226ea76cc819..966aab902d19 100644 --- a/drivers/block/zram/zram_drv.c +++ b/drivers/block/zram/zram_drv.c @@ -52,9 +52,6 @@ static unsigned int num_devices = 1; static size_t huge_class_size; static const struct block_device_operations zram_devops; -#ifdef CONFIG_ZRAM_WRITEBACK -static const struct block_device_operations zram_wb_devops; -#endif static void zram_free_page(struct zram *zram, size_t index); static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec, @@ -329,8 +326,8 @@ static ssize_t idle_store(struct device *dev, if (!sysfs_streq(buf, "all")) { /* - * If it did not parse as 'all' try to treat it as an integer when - * we have memory tracking enabled. + * If it did not parse as 'all' try to treat it as an integer + * when we have memory tracking enabled. */ u64 age_sec; @@ -345,7 +342,10 @@ static ssize_t idle_store(struct device *dev, if (!init_done(zram)) goto out_unlock; - /* A cutoff_time of 0 marks everything as idle, this is the "all" behavior */ + /* + * A cutoff_time of 0 marks everything as idle, this is the + * "all" behavior. + */ mark_idle(zram, cutoff_time); rv = len; @@ -499,7 +499,7 @@ static ssize_t backing_dev_store(struct device *dev, goto out; } - strlcpy(file_name, buf, PATH_MAX); + strscpy(file_name, buf, PATH_MAX); /* ignore trailing newline */ sz = strlen(file_name); if (sz > 0 && file_name[sz - 1] == '\n') @@ -543,17 +543,6 @@ static ssize_t backing_dev_store(struct device *dev, zram->backing_dev = backing_dev; zram->bitmap = bitmap; zram->nr_pages = nr_pages; - /* - * With writeback feature, zram does asynchronous IO so it's no longer - * synchronous device so let's remove synchronous io flag. Othewise, - * upper layer(e.g., swap) could wait IO completion rather than - * (submit and return), which will cause system sluggish. - * Furthermore, when the IO function returns(e.g., swap_readpage), - * upper layer expects IO was done so it could deallocate the page - * freely but in fact, IO is going on so finally could cause - * use-after-free when the IO is really done. - */ - zram->disk->fops = &zram_wb_devops; up_write(&zram->init_lock); pr_info("setup backing device %s\n", file_name); @@ -1031,7 +1020,7 @@ static ssize_t comp_algorithm_store(struct device *dev, char compressor[ARRAY_SIZE(zram->compressor)]; size_t sz; - strlcpy(compressor, buf, sizeof(compressor)); + strscpy(compressor, buf, sizeof(compressor)); /* ignore trailing newline */ sz = strlen(compressor); if (sz > 0 && compressor[sz - 1] == '\n') @@ -1267,6 +1256,9 @@ static int __zram_bvec_read(struct zram *zram, struct page *page, u32 index, struct bio_vec bvec; zram_slot_unlock(zram, index); + /* A null bio means rw_page was used, we must fallback to bio */ + if (!bio) + return -EOPNOTSUPP; bvec.bv_page = page; bvec.bv_len = PAGE_SIZE; @@ -1410,9 +1402,19 @@ compress_again: handle = zs_malloc(zram->mem_pool, comp_len, GFP_NOIO | __GFP_HIGHMEM | __GFP_MOVABLE); - if (!IS_ERR((void *)handle)) + if (IS_ERR((void *)handle)) + return PTR_ERR((void *)handle); + + if (comp_len != PAGE_SIZE) goto compress_again; - return PTR_ERR((void *)handle); + /* + * If the page is not compressible, you need to acquire the + * lock and execute the code below. The zcomp_stream_get() + * call is needed to disable the cpu hotplug and grab the + * zstrm buffer back. It is necessary that the dereferencing + * of the zstrm variable below occurs correctly. + */ + zstrm = zcomp_stream_get(zram->comp); } alloced_pages = zs_get_total_pages(zram->mem_pool); @@ -1710,9 +1712,6 @@ out: static void zram_reset_device(struct zram *zram) { - struct zcomp *comp; - u64 disksize; - down_write(&zram->init_lock); zram->limit_pages = 0; @@ -1722,17 +1721,15 @@ static void zram_reset_device(struct zram *zram) return; } - comp = zram->comp; - disksize = zram->disksize; - zram->disksize = 0; - set_capacity_and_notify(zram->disk, 0); part_stat_set_all(zram->disk->part0, 0); /* I/O operation under all of CPU are done so let's free */ - zram_meta_free(zram, disksize); + zram_meta_free(zram, zram->disksize); + zram->disksize = 0; memset(&zram->stats, 0, sizeof(zram->stats)); - zcomp_destroy(comp); + zcomp_destroy(zram->comp); + zram->comp = NULL; reset_bdev(zram); up_write(&zram->init_lock); @@ -1848,15 +1845,6 @@ static const struct block_device_operations zram_devops = { .owner = THIS_MODULE }; -#ifdef CONFIG_ZRAM_WRITEBACK -static const struct block_device_operations zram_wb_devops = { - .open = zram_open, - .submit_bio = zram_submit_bio, - .swap_slot_free_notify = zram_slot_free_notify, - .owner = THIS_MODULE -}; -#endif - static DEVICE_ATTR_WO(compact); static DEVICE_ATTR_RW(disksize); static DEVICE_ATTR_RO(initstate); @@ -1974,7 +1962,7 @@ static int zram_add(void) if (ret) goto out_cleanup_disk; - strlcpy(zram->compressor, default_compressor, sizeof(zram->compressor)); + strscpy(zram->compressor, default_compressor, sizeof(zram->compressor)); zram_debugfs_register(zram); pr_info("Added device: %s\n", zram->disk->disk_name); @@ -2126,6 +2114,8 @@ static int __init zram_init(void) { int ret; + BUILD_BUG_ON(__NR_ZRAM_PAGEFLAGS > BITS_PER_LONG); + ret = cpuhp_setup_state_multi(CPUHP_ZCOMP_PREPARE, "block/zram:prepare", zcomp_cpu_up_prepare, zcomp_cpu_dead); if (ret < 0) |