/* Module params (documentation at end) */
static unsigned int num_devices = 1;
+static inline struct zram *dev_to_zram(struct device *dev)
+{
+ return (struct zram *)dev_to_disk(dev)->private_data;
+}
+
+static ssize_t disksize_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct zram *zram = dev_to_zram(dev);
+
+ return sprintf(buf, "%llu\n", zram->disksize);
+}
+
+static ssize_t initstate_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct zram *zram = dev_to_zram(dev);
+
+ return sprintf(buf, "%u\n", zram->init_done);
+}
+
+static ssize_t num_reads_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct zram *zram = dev_to_zram(dev);
+
+ return sprintf(buf, "%llu\n",
+ (u64)atomic64_read(&zram->stats.num_reads));
+}
+
+static ssize_t num_writes_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct zram *zram = dev_to_zram(dev);
+
+ return sprintf(buf, "%llu\n",
+ (u64)atomic64_read(&zram->stats.num_writes));
+}
+
+static ssize_t invalid_io_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct zram *zram = dev_to_zram(dev);
+
+ return sprintf(buf, "%llu\n",
+ (u64)atomic64_read(&zram->stats.invalid_io));
+}
+
+static ssize_t notify_free_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct zram *zram = dev_to_zram(dev);
+
+ return sprintf(buf, "%llu\n",
+ (u64)atomic64_read(&zram->stats.notify_free));
+}
+
+static ssize_t zero_pages_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct zram *zram = dev_to_zram(dev);
+
+ return sprintf(buf, "%u\n", zram->stats.pages_zero);
+}
+
+static ssize_t orig_data_size_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct zram *zram = dev_to_zram(dev);
+
+ return sprintf(buf, "%llu\n",
+ (u64)(zram->stats.pages_stored) << PAGE_SHIFT);
+}
+
+static ssize_t compr_data_size_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct zram *zram = dev_to_zram(dev);
+
+ return sprintf(buf, "%llu\n",
+ (u64)atomic64_read(&zram->stats.compr_size));
+}
+
+static ssize_t mem_used_total_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ u64 val = 0;
+ struct zram *zram = dev_to_zram(dev);
+ struct zram_meta *meta = zram->meta;
+
+ down_read(&zram->init_lock);
+ if (zram->init_done)
+ val = zs_get_total_size_bytes(meta->mem_pool);
+ up_read(&zram->init_lock);
+
+ return sprintf(buf, "%llu\n", val);
+}
+
static int zram_test_flag(struct zram_meta *meta, u32 index,
enum zram_pageflags flag)
{
meta->table[index].flags &= ~BIT(flag);
}
+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, struct bio *bio)
+{
+ u64 start, end, bound;
+
+ /* unaligned request */
+ if (unlikely(bio->bi_sector & (ZRAM_SECTOR_PER_LOGICAL_BLOCK - 1)))
+ return 0;
+ if (unlikely(bio->bi_size & (ZRAM_LOGICAL_BLOCK_SIZE - 1)))
+ return 0;
+
+ start = bio->bi_sector;
+ end = start + (bio->bi_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 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);
+}
+
+static 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;
+
+ meta->compress_workmem = kzalloc(LZO1X_MEM_COMPRESS, GFP_KERNEL);
+ if (!meta->compress_workmem)
+ 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;
+}
+
+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;
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 void zram_free_page(struct zram *zram, size_t index)
{
struct zram_meta *meta = zram->meta;
meta->table[index].size = 0;
}
-static inline int is_partial_io(struct bio_vec *bvec)
-{
- return bvec->bv_len != PAGE_SIZE;
-}
-
-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 int zram_decompress_page(struct zram *zram, char *mem, u32 index)
{
int ret = LZO_E_OK;
return ret;
}
-static void update_position(u32 *index, int *offset, struct bio_vec *bvec)
+static void zram_reset_device(struct zram *zram)
{
- if (*offset + bvec->bv_len >= PAGE_SIZE)
- (*index)++;
- *offset = (*offset + bvec->bv_len) % PAGE_SIZE;
+ size_t index;
+ struct zram_meta *meta;
+
+ if (!zram->init_done)
+ return;
+
+ 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 = meta->table[index].handle;
+ if (!handle)
+ continue;
+
+ zs_free(meta->mem_pool, handle);
+ }
+
+ 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);
+}
+
+static 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;
+
+ pr_debug("Initialization done!\n");
+}
+
+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 = disksize;
+ set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT);
+ zram_init_device(zram, meta);
+ up_write(&zram->init_lock);
+
+ return len;
+}
+
+static ssize_t reset_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t len)
+{
+ int ret;
+ unsigned short do_reset;
+ struct zram *zram;
+ struct block_device *bdev;
+
+ zram = dev_to_zram(dev);
+ bdev = bdget_disk(zram->disk, 0);
+
+ /* Do not reset an active device! */
+ if (bdev->bd_holders)
+ return -EBUSY;
+
+ ret = kstrtou16(buf, 10, &do_reset);
+ if (ret)
+ return ret;
+
+ if (!do_reset)
+ return -EINVAL;
+
+ /* Make sure all pending I/O is finished */
+ if (bdev)
+ fsync_bdev(bdev);
+
+ zram_reset_device(zram);
+ return len;
}
static void __zram_make_request(struct zram *zram, struct bio *bio, int rw)
bio_io_error(bio);
}
-/*
- * Check if request is within bounds and aligned on zram logical blocks.
- */
-static inline int valid_io_request(struct zram *zram, struct bio *bio)
-{
- u64 start, end, bound;
-
- /* unaligned request */
- if (unlikely(bio->bi_sector & (ZRAM_SECTOR_PER_LOGICAL_BLOCK - 1)))
- return 0;
- if (unlikely(bio->bi_size & (ZRAM_LOGICAL_BLOCK_SIZE - 1)))
- return 0;
-
- start = bio->bi_sector;
- end = start + (bio->bi_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;
-}
-
/*
* Handler function for all zram I/O requests.
*/
bio_io_error(bio);
}
-static 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 all pages that are still in this zram device */
- for (index = 0; index < zram->disksize >> PAGE_SHIFT; index++) {
- unsigned long handle = meta->table[index].handle;
- if (!handle)
- continue;
-
- zs_free(meta->mem_pool, handle);
- }
-
- 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)
-{
- down_write(&zram->init_lock);
- __zram_reset_device(zram);
- up_write(&zram->init_lock);
-}
-
-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)
-{
- 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)
- 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 "
- "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;
-
- pr_debug("Initialization done!\n");
-}
-
static void zram_slot_free_notify(struct block_device *bdev,
unsigned long index)
{
.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(num_reads, S_IRUGO, num_reads_show, NULL);
+static DEVICE_ATTR(num_writes, S_IRUGO, num_writes_show, NULL);
+static DEVICE_ATTR(invalid_io, S_IRUGO, invalid_io_show, NULL);
+static DEVICE_ATTR(notify_free, S_IRUGO, notify_free_show, NULL);
+static DEVICE_ATTR(zero_pages, S_IRUGO, zero_pages_show, NULL);
+static DEVICE_ATTR(orig_data_size, S_IRUGO, orig_data_size_show, NULL);
+static DEVICE_ATTR(compr_data_size, S_IRUGO, compr_data_size_show, NULL);
+static DEVICE_ATTR(mem_used_total, S_IRUGO, mem_used_total_show, NULL);
+
+static struct attribute *zram_disk_attrs[] = {
+ &dev_attr_disksize.attr,
+ &dev_attr_initstate.attr,
+ &dev_attr_reset.attr,
+ &dev_attr_num_reads.attr,
+ &dev_attr_num_writes.attr,
+ &dev_attr_invalid_io.attr,
+ &dev_attr_notify_free.attr,
+ &dev_attr_zero_pages.attr,
+ &dev_attr_orig_data_size.attr,
+ &dev_attr_compr_data_size.attr,
+ &dev_attr_mem_used_total.attr,
+ NULL,
+};
+
+static struct attribute_group zram_disk_attr_group = {
+ .attrs = zram_disk_attrs,
+};
+
static int create_device(struct zram *zram, int device_id)
{
int ret = -ENOMEM;
pr_debug("Cleanup done!\n");
}
-module_param(num_devices, uint, 0);
-MODULE_PARM_DESC(num_devices, "Number of zram devices");
-
module_init(zram_init);
module_exit(zram_exit);
+module_param(num_devices, uint, 0);
+MODULE_PARM_DESC(num_devices, "Number of zram devices");
+
MODULE_LICENSE("Dual BSD/GPL");
MODULE_AUTHOR("Nitin Gupta <ngupta@vflare.org>");
MODULE_DESCRIPTION("Compressed RAM Block Device");
git.samba.org / sfrench / cifs-2.6.git / blobdiff