1 files changed, 130 insertions, 164 deletions

diff --git a/drivers/staging/zram/zram_drv.c b/drivers/staging/zram/zram_drv.c
index f2a73bd739fb..5918fd7d7e36 100644
--- a/drivers/staging/zram/zram_drv.c
+++ b/drivers/staging/zram/zram_drv.c
@@ -40,17 +40,7 @@ static int zram_major;
 struct zram *zram_devices;
 
 /* Module params (documentation at end) */
-static unsigned int num_devices;
-
-static void zram_stat_inc(u32 *v)
-{
-	*v = *v + 1;
-}
-
-static void zram_stat_dec(u32 *v)
-{
-	*v = *v - 1;
-}
+static unsigned int num_devices = 1;
 
 static void zram_stat64_add(struct zram *zram, u64 *v, u64 inc)
 {
@@ -71,22 +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)
@@ -104,66 +94,38 @@ static int page_zero_filled(void *ptr)
 	return 1;
 }
 
-static void zram_set_disksize(struct zram *zram, size_t totalram_bytes)
-{
-	if (!zram->disksize) {
-		pr_info(
-		"disk size not provided. You can use disksize_kb module "
-		"param to specify size.\nUsing default: (%u%% of RAM).\n",
-		default_disksize_perc_ram
-		);
-		zram->disksize = default_disksize_perc_ram *
-					(totalram_bytes / 100);
-	}
-
-	if (zram->disksize > 2 * (totalram_bytes)) {
-		pr_info(
-		"There is little point creating a zram of greater than "
-		"twice the size of memory since we expect a 2:1 compression "
-		"ratio. Note that zram uses about 0.1%% of the size of "
-		"the disk when not in use so a huge zram is "
-		"wasteful.\n"
-		"\tMemory Size: %zu kB\n"
-		"\tSize you selected: %llu kB\n"
-		"Continuing anyway ...\n",
-		totalram_bytes >> 10, zram->disksize
-		);
-	}
-
-	zram->disksize &= PAGE_MASK;
-}
-
 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);
-			zram_stat_dec(&zram->stats.pages_zero);
+		if (zram_test_flag(meta, index, ZRAM_ZERO)) {
+			zram_clear_flag(meta, index, ZRAM_ZERO);
+			zram->stats.pages_zero--;
 		}
 		return;
 	}
 
 	if (unlikely(size > max_zpage_size))
-		zram_stat_dec(&zram->stats.bad_compress);
+		zram->stats.bad_compress--;
 
-	zs_free(zram->mem_pool, handle);
+	zs_free(meta->mem_pool, handle);
 
 	if (size <= PAGE_SIZE / 2)
-		zram_stat_dec(&zram->stats.good_compress);
+		zram->stats.good_compress--;
 
 	zram_stat64_sub(zram, &zram->stats.compr_size,
-			zram->table[index].size);
-	zram_stat_dec(&zram->stats.pages_stored);
+			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)
@@ -188,20 +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)) {
@@ -219,20 +182,21 @@ 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;
 	}
 
-	user_mem = kmap_atomic(page);
 	if (is_partial_io(bvec))
 		/* Use  a temporary buffer to decompress the page */
-		uncmem = kmalloc(PAGE_SIZE, GFP_KERNEL);
-	else
+		uncmem = kmalloc(PAGE_SIZE, GFP_NOIO);
+
+	user_mem = kmap_atomic(page);
+	if (!is_partial_io(bvec))
 		uncmem = user_mem;
 
 	if (!uncmem) {
@@ -270,18 +234,18 @@ 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)) {
 		/*
 		 * This is a partial IO. We need to read the full page
 		 * before to write the changes.
 		 */
-		uncmem = kmalloc(PAGE_SIZE, GFP_KERNEL);
+		uncmem = kmalloc(PAGE_SIZE, GFP_NOIO);
 		if (!uncmem) {
-			pr_info("Error allocating temp memory!\n");
 			ret = -ENOMEM;
 			goto out;
 		}
@@ -294,8 +258,8 @@ 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);
@@ -310,16 +274,17 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
 	}
 
 	if (page_zero_filled(uncmem)) {
-		if (!is_partial_io(bvec))
-			kunmap_atomic(user_mem);
-		zram_stat_inc(&zram->stats.pages_zero);
-		zram_set_flag(zram, index, ZRAM_ZERO);
+		kunmap_atomic(user_mem);
+		if (is_partial_io(bvec))
+			kfree(uncmem);
+		zram->stats.pages_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);
@@ -333,21 +298,21 @@ static int zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index,
 	}
 
 	if (unlikely(clen > max_zpage_size)) {
-		zram_stat_inc(&zram->stats.bad_compress);
+		zram->stats.bad_compress++;
 		clen = PAGE_SIZE;
 		src = NULL;
 		if (is_partial_io(bvec))
 			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);
@@ -355,16 +320,16 @@ 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);
-	zram_stat_inc(&zram->stats.pages_stored);
+	zram->stats.pages_stored++;
 	if (clen <= PAGE_SIZE / 2)
-		zram_stat_inc(&zram->stats.good_compress);
+		zram->stats.good_compress++;
 
 out:
 	if (is_partial_io(bvec))
@@ -479,16 +444,13 @@ static void zram_make_request(struct request_queue *queue, struct bio *bio)
 {
 	struct zram *zram = queue->queuedata;
 
-	if (unlikely(!zram->init_done) && zram_init_device(zram))
-		goto error;
-
 	down_read(&zram->init_lock);
 	if (unlikely(!zram->init_done))
-		goto error_unlock;
+		goto error;
 
 	if (!valid_io_request(zram, bio)) {
 		zram_stat64_inc(zram, &zram->stats.invalid_io);
-		goto error_unlock;
+		goto error;
 	}
 
 	__zram_make_request(zram, bio, bio_data_dir(bio));
@@ -496,44 +458,38 @@ static void zram_make_request(struct request_queue *queue, struct bio *bio)
 
 	return;
 
-error_unlock:
-	up_read(&zram->init_lock);
 error:
+	up_read(&zram->init_lock);
 	bio_io_error(bio);
 }
 
-void __zram_reset_device(struct zram *zram)
+static void __zram_reset_device(struct zram *zram)
 {
 	size_t index;
+	struct zram_meta *meta;
 
-	zram->init_done = 0;
-
-	/* Free various per-device buffers */
-	kfree(zram->compress_workmem);
-	free_pages((unsigned long)zram->compress_buffer, 1);
+	if (!zram->init_done)
+		return;
 
-	zram->compress_workmem = NULL;
-	zram->compress_buffer = NULL;
+	meta = zram->meta;
+	zram->init_done = 0;
 
 	/* 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));
 
 	zram->disksize = 0;
+	set_capacity(zram->disk, 0);
 }
 
 void zram_reset_device(struct zram *zram)
@@ -543,69 +499,84 @@ void zram_reset_device(struct zram *zram)
 	up_write(&zram->init_lock);
 }
 
-int zram_init_device(struct zram *zram)
+void zram_meta_free(struct zram_meta *meta)
 {
-	int ret;
-	size_t num_pages;
-
-	down_write(&zram->init_lock);
-
-	if (zram->init_done) {
-		up_write(&zram->init_lock);
-		return 0;
-	}
+	zs_destroy_pool(meta->mem_pool);
+	kfree(meta->compress_workmem);
+	free_pages((unsigned long)meta->compress_buffer, 1);
+	vfree(meta->table);
+	kfree(meta);
+}
 
-	zram_set_disksize(zram, totalram_pages << PAGE_SHIFT);
+struct zram_meta *zram_meta_alloc(u64 disksize)
+{
+	size_t num_pages;
+	struct zram_meta *meta = kmalloc(sizeof(*meta), GFP_KERNEL);
+	if (!meta)
+		goto out;
 
-	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;
-	}
+	meta->compress_workmem = kzalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL);
+	if (!meta->compress_workmem)
+		goto free_meta;
 
-	zram->compress_buffer =
+	meta->compress_buffer =
 		(void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, 1);
-	if (!zram->compress_buffer) {
+	if (!meta->compress_buffer) {
 		pr_err("Error allocating compressor buffer space\n");
-		ret = -ENOMEM;
-		goto fail_no_table;
+		goto free_workmem;
 	}
 
-	num_pages = zram->disksize >> PAGE_SHIFT;
-	zram->table = vzalloc(num_pages * sizeof(*zram->table));
-	if (!zram->table) {
+	num_pages = disksize >> PAGE_SHIFT;
+	meta->table = vzalloc(num_pages * sizeof(*meta->table));
+	if (!meta->table) {
 		pr_err("Error allocating zram address table\n");
-		ret = -ENOMEM;
-		goto fail_no_table;
+		goto free_buffer;
 	}
 
-	set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT);
+	meta->mem_pool = zs_create_pool(GFP_NOIO | __GFP_HIGHMEM);
+	if (!meta->mem_pool) {
+		pr_err("Error creating memory pool\n");
+		goto free_table;
+	}
 
-	/* zram devices sort of resembles non-rotational disks */
-	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, zram->disk->queue);
+	return meta;
 
-	zram->mem_pool = zs_create_pool("zram", GFP_NOIO | __GFP_HIGHMEM);
-	if (!zram->mem_pool) {
-		pr_err("Error creating memory pool\n");
-		ret = -ENOMEM;
-		goto fail;
+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 "
+		"twice the size of memory since we expect a 2:1 compression "
+		"ratio. Note that zram uses about 0.1%% of the size of "
+		"the disk when not in use so a huge zram is "
+		"wasteful.\n"
+		"\tMemory Size: %lu kB\n"
+		"\tSize you selected: %llu kB\n"
+		"Continuing anyway ...\n",
+		(totalram_pages << PAGE_SHIFT) >> 10, zram->disksize >> 10
+		);
 	}
 
+	/* zram devices sort of resembles non-rotational disks */
+	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, zram->disk->queue);
+
+	zram->meta = meta;
 	zram->init_done = 1;
-	up_write(&zram->init_lock);
 
 	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);
-	up_write(&zram->init_lock);
-	pr_err("Initialization failed: err=%d\n", ret);
-	return ret;
 }
 
 static void zram_slot_free_notify(struct block_device *bdev,
@@ -724,13 +695,7 @@ static int __init zram_init(void)
 		goto out;
 	}
 
-	if (!num_devices) {
-		pr_info("num_devices not specified. Using default: 1\n");
-		num_devices = 1;
-	}
-
 	/* Allocate the device array and initialize each one */
-	pr_info("Creating %u devices ...\n", num_devices);
 	zram_devices = kzalloc(num_devices * sizeof(struct zram), GFP_KERNEL);
 	if (!zram_devices) {
 		ret = -ENOMEM;
@@ -743,6 +708,8 @@ static int __init zram_init(void)
 			goto free_devices;
 	}
 
+	pr_info("Created %u device(s) ...\n", num_devices);
+
 	return 0;
 
 free_devices:
@@ -764,8 +731,7 @@ static void __exit zram_exit(void)
 		zram = &zram_devices[i];
 
 		destroy_device(zram);
-		if (zram->init_done)
-			zram_reset_device(zram);
+		zram_reset_device(zram);
 	}
 
 	unregister_blkdev(zram_major, "zram");