zram: introduce zram data accessor

With element, sometime I got confused handle and element access.  It
might be my bad but I think it's time to introduce accessor to prevent
future idiot like me.  This patch is just clean-up patch so it shouldn't
change any behavior.

Link: http://lkml.kernel.org/r/1492052365-16169-6-git-send-email-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index c674d23539b1383777affc16945eabaffa764708..61b0f837422255947b1c78efa1073877282c2fd1 100644 (file)
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -57,6 +57,16 @@ static inline struct zram *dev_to_zram(struct device *dev)
        return (struct zram *)dev_to_disk(dev)->private_data;
 }
 
+static unsigned long zram_get_handle(struct zram *zram, u32 index)
+{
+       return zram->table[index].handle;
+}
+
+static void zram_set_handle(struct zram *zram, u32 index, unsigned long handle)
+{
+       zram->table[index].handle = handle;
+}
+
 /* flag operations require table entry bit_spin_lock() being held */
 static int zram_test_flag(struct zram *zram, u32 index,
                        enum zram_pageflags flag)
@@ -82,9 +92,9 @@ static inline void zram_set_element(struct zram *zram, u32 index,
        zram->table[index].element = element;
 }
 
-static inline void zram_clear_element(struct zram *zram, u32 index)
+static unsigned long zram_get_element(struct zram *zram, u32 index)
 {
-       zram->table[index].element = 0;
+       return zram->table[index].element;
 }
 
 static size_t zram_get_obj_size(struct zram *zram, u32 index)
@@ -425,13 +435,14 @@ static bool zram_same_page_read(struct zram *zram, u32 index,
                                unsigned int offset, unsigned int len)
 {
        zram_slot_lock(zram, index);
-       if (unlikely(!zram->table[index].handle) ||
-                       zram_test_flag(zram, index, ZRAM_SAME)) {
+       if (unlikely(!zram_get_handle(zram, index) ||
+                       zram_test_flag(zram, index, ZRAM_SAME))) {
                void *mem;
 
                zram_slot_unlock(zram, index);
                mem = kmap_atomic(page);
-               zram_fill_page(mem + offset, len, zram->table[index].element);
+               zram_fill_page(mem + offset, len,
+                                       zram_get_element(zram, index));
                kunmap_atomic(mem);
                return true;
        }
@@ -470,7 +481,7 @@ static void zram_meta_free(struct zram *zram, u64 disksize)
 
        /* Free all pages that are still in this zram device */
        for (index = 0; index < num_pages; index++) {
-               unsigned long handle = zram->table[index].handle;
+               unsigned long handle = zram_get_handle(zram, index);
                /*
                 * No memory is allocated for same element filled pages.
                 * Simply clear same page flag.
@@ -510,7 +521,7 @@ static bool zram_meta_alloc(struct zram *zram, u64 disksize)
  */
 static void zram_free_page(struct zram *zram, size_t index)
 {
-       unsigned long handle = zram->table[index].handle;
+       unsigned long handle = zram_get_handle(zram, index);
 
        /*
         * No memory is allocated for same element filled pages.
@@ -518,7 +529,7 @@ static void zram_free_page(struct zram *zram, size_t index)
         */
        if (zram_test_flag(zram, index, ZRAM_SAME)) {
                zram_clear_flag(zram, index, ZRAM_SAME);
-               zram_clear_element(zram, index);
+               zram_set_element(zram, index, 0);
                atomic64_dec(&zram->stats.same_pages);
                return;
        }
@@ -532,7 +543,7 @@ static void zram_free_page(struct zram *zram, size_t index)
                        &zram->stats.compr_data_size);
        atomic64_dec(&zram->stats.pages_stored);
 
-       zram->table[index].handle = 0;
+       zram_set_handle(zram, index, 0);
        zram_set_obj_size(zram, index, 0);
 }
 
@@ -547,7 +558,7 @@ static int zram_decompress_page(struct zram *zram, struct page *page, u32 index)
                return 0;
 
        zram_slot_lock(zram, index);
-       handle = zram->table[index].handle;
+       handle = zram_get_handle(zram, index);
        size = zram_get_obj_size(zram, index);
 
        src = zs_map_object(zram->mem_pool, handle, ZS_MM_RO);
@@ -713,7 +724,7 @@ static int __zram_bvec_write(struct zram *zram, struct bio_vec *bvec, u32 index)
         */
        zram_slot_lock(zram, index);
        zram_free_page(zram, index);
-       zram->table[index].handle = handle;
+       zram_set_handle(zram, index, handle);
        zram_set_obj_size(zram, index, comp_len);
        zram_slot_unlock(zram, index);