From 8b3cc3edb745cbc131560d19e3f32d81c07454b1 Mon Sep 17 00:00:00 2001 From: Minchan Kim Date: Wed, 6 Feb 2013 08:48:53 +0900 Subject: [PATCH] zram: get rid of lockdep warning Lockdep complains about recursive deadlock of zram->init_lock. [1] made it false positive because we can't request IO to zram before setting disksize. Anyway, we should shut lockdep up to avoid many reporting from user. [1] : zram: force disksize setting before using zram Acked-by: Jerome Marchand Acked-by: Nitin Gupta Signed-off-by: Minchan Kim Signed-off-by: Greg Kroah-Hartman --- drivers/staging/zram/zram_drv.c | 189 ++++++++++++++++-------------- drivers/staging/zram/zram_drv.h | 12 +- drivers/staging/zram/zram_sysfs.c | 11 +- 3 files changed, 116 insertions(+), 96 deletions(-) diff --git a/drivers/staging/zram/zram_drv.c b/drivers/staging/zram/zram_drv.c index 3318b0ff8f4d..9ac140bbabc5 100644 --- a/drivers/staging/zram/zram_drv.c +++ b/drivers/staging/zram/zram_drv.c @@ -61,22 +61,22 @@ static void zram_stat64_inc(struct zram *zram, u64 *v) zram_stat64_add(zram, v, 1); } -static int zram_test_flag(struct zram *zram, u32 index, +static int zram_test_flag(struct zram_meta *meta, u32 index, enum zram_pageflags flag) { - return zram->table[index].flags & BIT(flag); + return meta->table[index].flags & BIT(flag); } -static void zram_set_flag(struct zram *zram, u32 index, +static void zram_set_flag(struct zram_meta *meta, u32 index, enum zram_pageflags flag) { - zram->table[index].flags |= BIT(flag); + meta->table[index].flags |= BIT(flag); } -static void zram_clear_flag(struct zram *zram, u32 index, +static void zram_clear_flag(struct zram_meta *meta, u32 index, enum zram_pageflags flag) { - zram->table[index].flags &= ~BIT(flag); + meta->table[index].flags &= ~BIT(flag); } static int page_zero_filled(void *ptr) @@ -96,16 +96,17 @@ static int page_zero_filled(void *ptr) static void zram_free_page(struct zram *zram, size_t index) { - unsigned long handle = zram->table[index].handle; - u16 size = zram->table[index].size; + struct zram_meta *meta = zram->meta; + unsigned long handle = meta->table[index].handle; + u16 size = meta->table[index].size; if (unlikely(!handle)) { /* * No memory is allocated for zero filled pages. * Simply clear zero page flag. */ - if (zram_test_flag(zram, index, ZRAM_ZERO)) { - zram_clear_flag(zram, index, ZRAM_ZERO); + if (zram_test_flag(meta, index, ZRAM_ZERO)) { + zram_clear_flag(meta, index, ZRAM_ZERO); zram->stats.pages_zero--; } return; @@ -114,17 +115,17 @@ static void zram_free_page(struct zram *zram, size_t index) if (unlikely(size > max_zpage_size)) zram->stats.bad_compress--; - zs_free(zram->mem_pool, handle); + zs_free(meta->mem_pool, handle); if (size <= PAGE_SIZE / 2) zram->stats.good_compress--; zram_stat64_sub(zram, &zram->stats.compr_size, - zram->table[index].size); + meta->table[index].size); zram->stats.pages_stored--; - zram->table[index].handle = 0; - zram->table[index].size = 0; + meta->table[index].handle = 0; + meta->table[index].size = 0; } static void handle_zero_page(struct bio_vec *bvec) @@ -149,20 +150,21 @@ static int zram_decompress_page(struct zram *zram, char *mem, u32 index) int ret = LZO_E_OK; size_t clen = PAGE_SIZE; unsigned char *cmem; - unsigned long handle = zram->table[index].handle; + struct zram_meta *meta = zram->meta; + unsigned long handle = meta->table[index].handle; - if (!handle || zram_test_flag(zram, index, ZRAM_ZERO)) { + if (!handle || zram_test_flag(meta, index, ZRAM_ZERO)) { memset(mem, 0, PAGE_SIZE); return 0; } - cmem = zs_map_object(zram->mem_pool, handle, ZS_MM_RO); - if (zram->table[index].size == PAGE_SIZE) + cmem = zs_map_object(meta->mem_pool, handle, ZS_MM_RO); + if (meta->table[index].size == PAGE_SIZE) memcpy(mem, cmem, PAGE_SIZE); else - ret = lzo1x_decompress_safe(cmem, zram->table[index].size, + ret = lzo1x_decompress_safe(cmem, meta->table[index].size, mem, &clen); - zs_unmap_object(zram->mem_pool, handle); + zs_unmap_object(meta->mem_pool, handle); /* Should NEVER happen. Return bio error if it does. */ if (unlikely(ret != LZO_E_OK)) { @@ -180,11 +182,11 @@ static int zram_bvec_read(struct zram *zram, struct bio_vec *bvec, int ret; struct page *page; unsigned char *user_mem, *uncmem = NULL; - + struct zram_meta *meta = zram->meta; page = bvec->bv_page; - if (unlikely(!zram->table[index].handle) || - zram_test_flag(zram, index, ZRAM_ZERO)) { + if (unlikely(!meta->table[index].handle) || + zram_test_flag(meta, index, ZRAM_ZERO)) { handle_zero_page(bvec); return 0; } @@ -232,9 +234,10 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index, unsigned long handle; struct page *page; unsigned char *user_mem, *cmem, *src, *uncmem = NULL; + struct zram_meta *meta = zram->meta; page = bvec->bv_page; - src = zram->compress_buffer; + src = meta->compress_buffer; if (is_partial_io(bvec)) { /* @@ -256,8 +259,8 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index, * System overwrites unused sectors. Free memory associated * with this sector now. */ - if (zram->table[index].handle || - zram_test_flag(zram, index, ZRAM_ZERO)) + if (meta->table[index].handle || + zram_test_flag(meta, index, ZRAM_ZERO)) zram_free_page(zram, index); user_mem = kmap_atomic(page); @@ -276,13 +279,13 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index, if (is_partial_io(bvec)) kfree(uncmem); zram->stats.pages_zero++; - zram_set_flag(zram, index, ZRAM_ZERO); + zram_set_flag(meta, index, ZRAM_ZERO); ret = 0; goto out; } ret = lzo1x_1_compress(uncmem, PAGE_SIZE, src, &clen, - zram->compress_workmem); + meta->compress_workmem); if (!is_partial_io(bvec)) { kunmap_atomic(user_mem); @@ -303,14 +306,14 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index, src = uncmem; } - handle = zs_malloc(zram->mem_pool, clen); + handle = zs_malloc(meta->mem_pool, clen); if (!handle) { pr_info("Error allocating memory for compressed " "page: %u, size=%zu\n", index, clen); ret = -ENOMEM; goto out; } - cmem = zs_map_object(zram->mem_pool, handle, ZS_MM_WO); + cmem = zs_map_object(meta->mem_pool, handle, ZS_MM_WO); if ((clen == PAGE_SIZE) && !is_partial_io(bvec)) src = kmap_atomic(page); @@ -318,10 +321,10 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index, if ((clen == PAGE_SIZE) && !is_partial_io(bvec)) kunmap_atomic(src); - zs_unmap_object(zram->mem_pool, handle); + zs_unmap_object(meta->mem_pool, handle); - zram->table[index].handle = handle; - zram->table[index].size = clen; + meta->table[index].handle = handle; + meta->table[index].size = clen; /* Update stats */ zram_stat64_add(zram, &zram->stats.compr_size, clen); @@ -464,34 +467,25 @@ error: void __zram_reset_device(struct zram *zram) { size_t index; + struct zram_meta *meta; if (!zram->init_done) return; + meta = zram->meta; zram->init_done = 0; - /* Free various per-device buffers */ - kfree(zram->compress_workmem); - free_pages((unsigned long)zram->compress_buffer, 1); - - zram->compress_workmem = NULL; - zram->compress_buffer = NULL; - /* Free all pages that are still in this zram device */ for (index = 0; index < zram->disksize >> PAGE_SHIFT; index++) { - unsigned long handle = zram->table[index].handle; + unsigned long handle = meta->table[index].handle; if (!handle) continue; - zs_free(zram->mem_pool, handle); + zs_free(meta->mem_pool, handle); } - vfree(zram->table); - zram->table = NULL; - - zs_destroy_pool(zram->mem_pool); - zram->mem_pool = NULL; - + zram_meta_free(zram->meta); + zram->meta = NULL; /* Reset stats */ memset(&zram->stats, 0, sizeof(zram->stats)); @@ -506,12 +500,65 @@ void zram_reset_device(struct zram *zram) up_write(&zram->init_lock); } -/* zram->init_lock should be held */ -int zram_init_device(struct zram *zram) +void zram_meta_free(struct zram_meta *meta) +{ + zs_destroy_pool(meta->mem_pool); + kfree(meta->compress_workmem); + free_pages((unsigned long)meta->compress_buffer, 1); + vfree(meta->table); + kfree(meta); +} + +struct zram_meta *zram_meta_alloc(u64 disksize) { - int ret; size_t num_pages; + struct zram_meta *meta = kmalloc(sizeof(*meta), GFP_KERNEL); + if (!meta) + goto out; + + meta->compress_workmem = kzalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL); + if (!meta->compress_workmem) { + pr_err("Error allocating compressor working memory!\n"); + goto free_meta; + } + + meta->compress_buffer = + (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, 1); + if (!meta->compress_buffer) { + pr_err("Error allocating compressor buffer space\n"); + goto free_workmem; + } + + num_pages = disksize >> PAGE_SHIFT; + meta->table = vzalloc(num_pages * sizeof(*meta->table)); + if (!meta->table) { + pr_err("Error allocating zram address table\n"); + goto free_buffer; + } + + meta->mem_pool = zs_create_pool(GFP_NOIO | __GFP_HIGHMEM); + if (!meta->mem_pool) { + pr_err("Error creating memory pool\n"); + goto free_table; + } + + return meta; + +free_table: + vfree(meta->table); +free_buffer: + free_pages((unsigned long)meta->compress_buffer, 1); +free_workmem: + kfree(meta->compress_workmem); +free_meta: + kfree(meta); + meta = NULL; +out: + return meta; +} +void zram_init_device(struct zram *zram, struct zram_meta *meta) +{ if (zram->disksize > 2 * (totalram_pages << PAGE_SHIFT)) { pr_info( "There is little point creating a zram of greater than " @@ -526,51 +573,13 @@ int zram_init_device(struct zram *zram) ); } - zram->compress_workmem = kzalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL); - if (!zram->compress_workmem) { - pr_err("Error allocating compressor working memory!\n"); - ret = -ENOMEM; - goto fail_no_table; - } - - zram->compress_buffer = - (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, 1); - if (!zram->compress_buffer) { - pr_err("Error allocating compressor buffer space\n"); - ret = -ENOMEM; - goto fail_no_table; - } - - num_pages = zram->disksize >> PAGE_SHIFT; - zram->table = vzalloc(num_pages * sizeof(*zram->table)); - if (!zram->table) { - pr_err("Error allocating zram address table\n"); - ret = -ENOMEM; - goto fail_no_table; - } - /* zram devices sort of resembles non-rotational disks */ queue_flag_set_unlocked(QUEUE_FLAG_NONROT, zram->disk->queue); - zram->mem_pool = zs_create_pool(GFP_NOIO | __GFP_HIGHMEM); - if (!zram->mem_pool) { - pr_err("Error creating memory pool\n"); - ret = -ENOMEM; - goto fail; - } - + zram->meta = meta; zram->init_done = 1; pr_debug("Initialization done!\n"); - return 0; - -fail_no_table: - /* To prevent accessing table entries during cleanup */ - zram->disksize = 0; -fail: - __zram_reset_device(zram); - pr_err("Initialization failed: err=%d\n", ret); - return ret; } static void zram_slot_free_notify(struct block_device *bdev, diff --git a/drivers/staging/zram/zram_drv.h b/drivers/staging/zram/zram_drv.h index 5b671d177e1c..2d1a3f1e8edb 100644 --- a/drivers/staging/zram/zram_drv.h +++ b/drivers/staging/zram/zram_drv.h @@ -83,11 +83,15 @@ struct zram_stats { u32 bad_compress; /* % of pages with compression ratio>=75% */ }; -struct zram { - struct zs_pool *mem_pool; +struct zram_meta { void *compress_workmem; void *compress_buffer; struct table *table; + struct zs_pool *mem_pool; +}; + +struct zram { + struct zram_meta *meta; spinlock_t stat64_lock; /* protect 64-bit stats */ struct rw_semaphore lock; /* protect compression buffers and table * against concurrent read and writes */ @@ -111,7 +115,9 @@ unsigned int zram_get_num_devices(void); extern struct attribute_group zram_disk_attr_group; #endif -extern int zram_init_device(struct zram *zram); extern void zram_reset_device(struct zram *zram); +extern struct zram_meta *zram_meta_alloc(u64 disksize); +extern void zram_meta_free(struct zram_meta *meta); +extern void zram_init_device(struct zram *zram, struct zram_meta *meta); #endif diff --git a/drivers/staging/zram/zram_sysfs.c b/drivers/staging/zram/zram_sysfs.c index 369db1250f96..e6a929d452f7 100644 --- a/drivers/staging/zram/zram_sysfs.c +++ b/drivers/staging/zram/zram_sysfs.c @@ -56,22 +56,26 @@ static ssize_t disksize_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t len) { u64 disksize; + struct zram_meta *meta; struct zram *zram = dev_to_zram(dev); disksize = memparse(buf, NULL); if (!disksize) return -EINVAL; + disksize = PAGE_ALIGN(disksize); + meta = zram_meta_alloc(disksize); down_write(&zram->init_lock); if (zram->init_done) { up_write(&zram->init_lock); + zram_meta_free(meta); pr_info("Cannot change disksize for initialized device\n"); return -EBUSY; } - zram->disksize = PAGE_ALIGN(disksize); + zram->disksize = disksize; set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT); - zram_init_device(zram); + zram_init_device(zram, meta); up_write(&zram->init_lock); return len; @@ -182,9 +186,10 @@ static ssize_t mem_used_total_show(struct device *dev, { u64 val = 0; struct zram *zram = dev_to_zram(dev); + struct zram_meta *meta = zram->meta; if (zram->init_done) - val = zs_get_total_size_bytes(zram->mem_pool); + val = zs_get_total_size_bytes(meta->mem_pool); return sprintf(buf, "%llu\n", val); } -- 2.20.1