zram: remove zram_meta structure
authorMinchan Kim <minchan@kernel.org>
Wed, 3 May 2017 21:55:47 +0000 (14:55 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Wed, 3 May 2017 22:52:11 +0000 (15:52 -0700)
It's redundant now.  Instead, remove it and use zram structure directly.

Link: http://lkml.kernel.org/r/1492052365-16169-5-git-send-email-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/block/zram/zram_drv.c
drivers/block/zram/zram_drv.h

index aac48ff6961834467e8a8d5f2dc88f53ad0f42f6..c674d23539b1383777affc16945eabaffa764708 100644 (file)
@@ -58,46 +58,46 @@ static inline struct zram *dev_to_zram(struct device *dev)
 }
 
 /* flag operations require table entry bit_spin_lock() being held */
-static int zram_test_flag(struct zram_meta *meta, u32 index,
+static int zram_test_flag(struct zram *zram, u32 index,
                        enum zram_pageflags flag)
 {
-       return meta->table[index].value & BIT(flag);
+       return zram->table[index].value & BIT(flag);
 }
 
-static void zram_set_flag(struct zram_meta *meta, u32 index,
+static void zram_set_flag(struct zram *zram, u32 index,
                        enum zram_pageflags flag)
 {
-       meta->table[index].value |= BIT(flag);
+       zram->table[index].value |= BIT(flag);
 }
 
-static void zram_clear_flag(struct zram_meta *meta, u32 index,
+static void zram_clear_flag(struct zram *zram, u32 index,
                        enum zram_pageflags flag)
 {
-       meta->table[index].value &= ~BIT(flag);
+       zram->table[index].value &= ~BIT(flag);
 }
 
-static inline void zram_set_element(struct zram_meta *meta, u32 index,
+static inline void zram_set_element(struct zram *zram, u32 index,
                        unsigned long element)
 {
-       meta->table[index].element = element;
+       zram->table[index].element = element;
 }
 
-static inline void zram_clear_element(struct zram_meta *meta, u32 index)
+static inline void zram_clear_element(struct zram *zram, u32 index)
 {
-       meta->table[index].element = 0;
+       zram->table[index].element = 0;
 }
 
-static size_t zram_get_obj_size(struct zram_meta *meta, u32 index)
+static size_t zram_get_obj_size(struct zram *zram, u32 index)
 {
-       return meta->table[index].value & (BIT(ZRAM_FLAG_SHIFT) - 1);
+       return zram->table[index].value & (BIT(ZRAM_FLAG_SHIFT) - 1);
 }
 
-static void zram_set_obj_size(struct zram_meta *meta,
+static void zram_set_obj_size(struct zram *zram,
                                        u32 index, size_t size)
 {
-       unsigned long flags = meta->table[index].value >> ZRAM_FLAG_SHIFT;
+       unsigned long flags = zram->table[index].value >> ZRAM_FLAG_SHIFT;
 
-       meta->table[index].value = (flags << ZRAM_FLAG_SHIFT) | size;
+       zram->table[index].value = (flags << ZRAM_FLAG_SHIFT) | size;
 }
 
 #if PAGE_SIZE != 4096
@@ -250,9 +250,8 @@ static ssize_t mem_used_max_store(struct device *dev,
 
        down_read(&zram->init_lock);
        if (init_done(zram)) {
-               struct zram_meta *meta = zram->meta;
                atomic_long_set(&zram->stats.max_used_pages,
-                               zs_get_total_pages(meta->mem_pool));
+                               zs_get_total_pages(zram->mem_pool));
        }
        up_read(&zram->init_lock);
 
@@ -325,7 +324,6 @@ static ssize_t compact_store(struct device *dev,
                struct device_attribute *attr, const char *buf, size_t len)
 {
        struct zram *zram = dev_to_zram(dev);
-       struct zram_meta *meta;
 
        down_read(&zram->init_lock);
        if (!init_done(zram)) {
@@ -333,8 +331,7 @@ static ssize_t compact_store(struct device *dev,
                return -EINVAL;
        }
 
-       meta = zram->meta;
-       zs_compact(meta->mem_pool);
+       zs_compact(zram->mem_pool);
        up_read(&zram->init_lock);
 
        return len;
@@ -371,8 +368,8 @@ static ssize_t mm_stat_show(struct device *dev,
 
        down_read(&zram->init_lock);
        if (init_done(zram)) {
-               mem_used = zs_get_total_pages(zram->meta->mem_pool);
-               zs_pool_stats(zram->meta->mem_pool, &pool_stats);
+               mem_used = zs_get_total_pages(zram->mem_pool);
+               zs_pool_stats(zram->mem_pool, &pool_stats);
        }
 
        orig_size = atomic64_read(&zram->stats.pages_stored);
@@ -415,32 +412,26 @@ static DEVICE_ATTR_RO(debug_stat);
 
 static void zram_slot_lock(struct zram *zram, u32 index)
 {
-       struct zram_meta *meta = zram->meta;
-
-       bit_spin_lock(ZRAM_ACCESS, &meta->table[index].value);
+       bit_spin_lock(ZRAM_ACCESS, &zram->table[index].value);
 }
 
 static void zram_slot_unlock(struct zram *zram, u32 index)
 {
-       struct zram_meta *meta = zram->meta;
-
-       bit_spin_unlock(ZRAM_ACCESS, &meta->table[index].value);
+       bit_spin_unlock(ZRAM_ACCESS, &zram->table[index].value);
 }
 
 static bool zram_same_page_read(struct zram *zram, u32 index,
                                struct page *page,
                                unsigned int offset, unsigned int len)
 {
-       struct zram_meta *meta = zram->meta;
-
        zram_slot_lock(zram, index);
-       if (unlikely(!meta->table[index].handle) ||
-                       zram_test_flag(meta, index, ZRAM_SAME)) {
+       if (unlikely(!zram->table[index].handle) ||
+                       zram_test_flag(zram, index, ZRAM_SAME)) {
                void *mem;
 
                zram_slot_unlock(zram, index);
                mem = kmap_atomic(page);
-               zram_fill_page(mem + offset, len, meta->table[index].element);
+               zram_fill_page(mem + offset, len, zram->table[index].element);
                kunmap_atomic(mem);
                return true;
        }
@@ -456,14 +447,12 @@ static bool zram_same_page_write(struct zram *zram, u32 index,
        void *mem = kmap_atomic(page);
 
        if (page_same_filled(mem, &element)) {
-               struct zram_meta *meta = zram->meta;
-
                kunmap_atomic(mem);
                /* Free memory associated with this sector now. */
                zram_slot_lock(zram, index);
                zram_free_page(zram, index);
-               zram_set_flag(meta, index, ZRAM_SAME);
-               zram_set_element(meta, index, element);
+               zram_set_flag(zram, index, ZRAM_SAME);
+               zram_set_element(zram, index, element);
                zram_slot_unlock(zram, index);
 
                atomic64_inc(&zram->stats.same_pages);
@@ -474,56 +463,44 @@ static bool zram_same_page_write(struct zram *zram, u32 index,
        return false;
 }
 
-static void zram_meta_free(struct zram_meta *meta, u64 disksize)
+static void zram_meta_free(struct zram *zram, u64 disksize)
 {
        size_t num_pages = disksize >> PAGE_SHIFT;
        size_t index;
 
        /* Free all pages that are still in this zram device */
        for (index = 0; index < num_pages; index++) {
-               unsigned long handle = meta->table[index].handle;
+               unsigned long handle = zram->table[index].handle;
                /*
                 * No memory is allocated for same element filled pages.
                 * Simply clear same page flag.
                 */
-               if (!handle || zram_test_flag(meta, index, ZRAM_SAME))
+               if (!handle || zram_test_flag(zram, index, ZRAM_SAME))
                        continue;
 
-               zs_free(meta->mem_pool, handle);
+               zs_free(zram->mem_pool, handle);
        }
 
-       zs_destroy_pool(meta->mem_pool);
-       vfree(meta->table);
-       kfree(meta);
+       zs_destroy_pool(zram->mem_pool);
+       vfree(zram->table);
 }
 
-static struct zram_meta *zram_meta_alloc(char *pool_name, u64 disksize)
+static bool zram_meta_alloc(struct zram *zram, u64 disksize)
 {
        size_t num_pages;
-       struct zram_meta *meta = kmalloc(sizeof(*meta), GFP_KERNEL);
-
-       if (!meta)
-               return NULL;
 
        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 out_error;
-       }
+       zram->table = vzalloc(num_pages * sizeof(*zram->table));
+       if (!zram->table)
+               return false;
 
-       meta->mem_pool = zs_create_pool(pool_name);
-       if (!meta->mem_pool) {
-               pr_err("Error creating memory pool\n");
-               goto out_error;
+       zram->mem_pool = zs_create_pool(zram->disk->disk_name);
+       if (!zram->mem_pool) {
+               vfree(zram->table);
+               return false;
        }
 
-       return meta;
-
-out_error:
-       vfree(meta->table);
-       kfree(meta);
-       return NULL;
+       return true;
 }
 
 /*
@@ -533,16 +510,15 @@ out_error:
  */
 static void zram_free_page(struct zram *zram, size_t index)
 {
-       struct zram_meta *meta = zram->meta;
-       unsigned long handle = meta->table[index].handle;
+       unsigned long handle = zram->table[index].handle;
 
        /*
         * No memory is allocated for same element filled pages.
         * Simply clear same page flag.
         */
-       if (zram_test_flag(meta, index, ZRAM_SAME)) {
-               zram_clear_flag(meta, index, ZRAM_SAME);
-               zram_clear_element(meta, index);
+       if (zram_test_flag(zram, index, ZRAM_SAME)) {
+               zram_clear_flag(zram, index, ZRAM_SAME);
+               zram_clear_element(zram, index);
                atomic64_dec(&zram->stats.same_pages);
                return;
        }
@@ -550,14 +526,14 @@ static void zram_free_page(struct zram *zram, size_t index)
        if (!handle)
                return;
 
-       zs_free(meta->mem_pool, handle);
+       zs_free(zram->mem_pool, handle);
 
-       atomic64_sub(zram_get_obj_size(meta, index),
+       atomic64_sub(zram_get_obj_size(zram, index),
                        &zram->stats.compr_data_size);
        atomic64_dec(&zram->stats.pages_stored);
 
-       meta->table[index].handle = 0;
-       zram_set_obj_size(meta, index, 0);
+       zram->table[index].handle = 0;
+       zram_set_obj_size(zram, index, 0);
 }
 
 static int zram_decompress_page(struct zram *zram, struct page *page, u32 index)
@@ -566,16 +542,15 @@ static int zram_decompress_page(struct zram *zram, struct page *page, u32 index)
        unsigned long handle;
        unsigned int size;
        void *src, *dst;
-       struct zram_meta *meta = zram->meta;
 
        if (zram_same_page_read(zram, index, page, 0, PAGE_SIZE))
                return 0;
 
        zram_slot_lock(zram, index);
-       handle = meta->table[index].handle;
-       size = zram_get_obj_size(meta, index);
+       handle = zram->table[index].handle;
+       size = zram_get_obj_size(zram, index);
 
-       src = zs_map_object(meta->mem_pool, handle, ZS_MM_RO);
+       src = zs_map_object(zram->mem_pool, handle, ZS_MM_RO);
        if (size == PAGE_SIZE) {
                dst = kmap_atomic(page);
                memcpy(dst, src, PAGE_SIZE);
@@ -589,7 +564,7 @@ static int zram_decompress_page(struct zram *zram, struct page *page, u32 index)
                kunmap_atomic(dst);
                zcomp_stream_put(zram->comp);
        }
-       zs_unmap_object(meta->mem_pool, handle);
+       zs_unmap_object(zram->mem_pool, handle);
        zram_slot_unlock(zram, index);
 
        /* Should NEVER happen. Return bio error if it does. */
@@ -641,7 +616,6 @@ static int zram_compress(struct zram *zram, struct zcomp_strm **zstrm,
        void *src;
        unsigned long alloced_pages;
        unsigned long handle = 0;
-       struct zram_meta *meta = zram->meta;
 
 compress_again:
        src = kmap_atomic(page);
@@ -651,7 +625,7 @@ compress_again:
        if (unlikely(ret)) {
                pr_err("Compression failed! err=%d\n", ret);
                if (handle)
-                       zs_free(meta->mem_pool, handle);
+                       zs_free(zram->mem_pool, handle);
                return ret;
        }
 
@@ -672,7 +646,7 @@ compress_again:
         * from the slow path and handle has already been allocated.
         */
        if (!handle)
-               handle = zs_malloc(meta->mem_pool, comp_len,
+               handle = zs_malloc(zram->mem_pool, comp_len,
                                __GFP_KSWAPD_RECLAIM |
                                __GFP_NOWARN |
                                __GFP_HIGHMEM |
@@ -680,7 +654,7 @@ compress_again:
        if (!handle) {
                zcomp_stream_put(zram->comp);
                atomic64_inc(&zram->stats.writestall);
-               handle = zs_malloc(meta->mem_pool, comp_len,
+               handle = zs_malloc(zram->mem_pool, comp_len,
                                GFP_NOIO | __GFP_HIGHMEM |
                                __GFP_MOVABLE);
                *zstrm = zcomp_stream_get(zram->comp);
@@ -689,11 +663,11 @@ compress_again:
                return -ENOMEM;
        }
 
-       alloced_pages = zs_get_total_pages(meta->mem_pool);
+       alloced_pages = zs_get_total_pages(zram->mem_pool);
        update_used_max(zram, alloced_pages);
 
        if (zram->limit_pages && alloced_pages > zram->limit_pages) {
-               zs_free(meta->mem_pool, handle);
+               zs_free(zram->mem_pool, handle);
                return -ENOMEM;
        }
 
@@ -709,7 +683,6 @@ static int __zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index)
        unsigned int comp_len;
        void *src, *dst;
        struct zcomp_strm *zstrm;
-       struct zram_meta *meta = zram->meta;
        struct page *page = bvec->bv_page;
 
        if (zram_same_page_write(zram, index, page))
@@ -722,8 +695,7 @@ static int __zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index)
                return ret;
        }
 
-
-       dst = zs_map_object(meta->mem_pool, handle, ZS_MM_WO);
+       dst = zs_map_object(zram->mem_pool, handle, ZS_MM_WO);
 
        src = zstrm->buffer;
        if (comp_len == PAGE_SIZE)
@@ -733,7 +705,7 @@ static int __zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index)
                kunmap_atomic(src);
 
        zcomp_stream_put(zram->comp);
-       zs_unmap_object(meta->mem_pool, handle);
+       zs_unmap_object(zram->mem_pool, handle);
 
        /*
         * Free memory associated with this sector
@@ -741,8 +713,8 @@ static int __zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index)
         */
        zram_slot_lock(zram, index);
        zram_free_page(zram, index);
-       meta->table[index].handle = handle;
-       zram_set_obj_size(meta, index, comp_len);
+       zram->table[index].handle = handle;
+       zram_set_obj_size(zram, index, comp_len);
        zram_slot_unlock(zram, index);
 
        /* Update stats */
@@ -932,10 +904,8 @@ 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;
 
        zram_slot_lock(zram, index);
        zram_free_page(zram, index);
@@ -983,7 +953,6 @@ out:
 
 static void zram_reset_device(struct zram *zram)
 {
-       struct zram_meta *meta;
        struct zcomp *comp;
        u64 disksize;
 
@@ -996,7 +965,6 @@ static void zram_reset_device(struct zram *zram)
                return;
        }
 
-       meta = zram->meta;
        comp = zram->comp;
        disksize = zram->disksize;
 
@@ -1009,7 +977,7 @@ static void zram_reset_device(struct zram *zram)
 
        up_write(&zram->init_lock);
        /* I/O operation under all of CPU are done so let's free */
-       zram_meta_free(meta, disksize);
+       zram_meta_free(zram, disksize);
        zcomp_destroy(comp);
 }
 
@@ -1018,7 +986,6 @@ static ssize_t disksize_store(struct device *dev,
 {
        u64 disksize;
        struct zcomp *comp;
-       struct zram_meta *meta;
        struct zram *zram = dev_to_zram(dev);
        int err;
 
@@ -1026,10 +993,18 @@ static ssize_t disksize_store(struct device *dev,
        if (!disksize)
                return -EINVAL;
 
+       down_write(&zram->init_lock);
+       if (init_done(zram)) {
+               pr_info("Cannot change disksize for initialized device\n");
+               err = -EBUSY;
+               goto out_unlock;
+       }
+
        disksize = PAGE_ALIGN(disksize);
-       meta = zram_meta_alloc(zram->disk->disk_name, disksize);
-       if (!meta)
-               return -ENOMEM;
+       if (!zram_meta_alloc(zram, disksize)) {
+               err = -ENOMEM;
+               goto out_unlock;
+       }
 
        comp = zcomp_create(zram->compressor);
        if (IS_ERR(comp)) {
@@ -1039,14 +1014,6 @@ static ssize_t disksize_store(struct device *dev,
                goto out_free_meta;
        }
 
-       down_write(&zram->init_lock);
-       if (init_done(zram)) {
-               pr_info("Cannot change disksize for initialized device\n");
-               err = -EBUSY;
-               goto out_destroy_comp;
-       }
-
-       zram->meta = meta;
        zram->comp = comp;
        zram->disksize = disksize;
        set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT);
@@ -1055,11 +1022,10 @@ static ssize_t disksize_store(struct device *dev,
 
        return len;
 
-out_destroy_comp:
-       up_write(&zram->init_lock);
-       zcomp_destroy(comp);
 out_free_meta:
-       zram_meta_free(meta, disksize);
+       zram_meta_free(zram, disksize);
+out_unlock:
+       up_write(&zram->init_lock);
        return err;
 }
 
@@ -1245,7 +1211,6 @@ static int zram_add(void)
                goto out_free_disk;
        }
        strlcpy(zram->compressor, default_compressor, sizeof(zram->compressor));
-       zram->meta = NULL;
 
        pr_info("Added device: %s\n", zram->disk->disk_name);
        return device_id;
index caeff51f1571af0957112bc28fe020f522503f94..e34e44d02e3ec63d58ee7f9c9b6b3694c74482a0 100644 (file)
@@ -92,13 +92,9 @@ struct zram_stats {
        atomic64_t writestall;          /* no. of write slow paths */
 };
 
-struct zram_meta {
+struct zram {
        struct zram_table_entry *table;
        struct zs_pool *mem_pool;
-};
-
-struct zram {
-       struct zram_meta *meta;
        struct zcomp *comp;
        struct gendisk *disk;
        /* Prevent concurrent execution of device init */