Postreview changes.

include/my_sys.h:
  The comments added.
include/pagecache.h:
  Functions names changed.
storage/maria/unittest/mf_pagecache_consist.c:
  Functions names changed.
storage/maria/unittest/mf_pagecache_single.c:
  Functions names changed.

include/my_sys.h

@@ -280,7 +280,12 @@ enum cache_type
 
 enum flush_type
 {
-  FLUSH_KEEP, FLUSH_RELEASE, FLUSH_IGNORE_CHANGED, FLUSH_FORCE_WRITE
+  FLUSH_KEEP,           /* flush block and keep it in the cache */
+  FLUSH_RELEASE,        /* flush block and remove it from the cache */
+  FLUSH_IGNORE_CHANGED, /* remove block from the cache */
+  /* as my_disable_flush_pagecache_blocks is always 0, it is
+     strictly equivalent to FLUSH_KEEP */
+  FLUSH_FORCE_WRITE
 };
 
 typedef struct st_record_cache	/* Used when cacheing records */

include/pagecache.h

@@ -194,26 +194,26 @@ extern my_bool pagecache_write(PAGECACHE *pagecache,
                                enum pagecache_page_pin pin,
                                enum pagecache_write_mode write_mode,
                                PAGECACHE_PAGE_LINK *link);
-extern void pagecache_unlock_page(PAGECACHE *pagecache,
+extern void pagecache_unlock(PAGECACHE *pagecache,
                              PAGECACHE_FILE *file,
                              pgcache_page_no_t pageno,
                              enum pagecache_page_lock lock,
                              enum pagecache_page_pin pin,
                              LSN first_REDO_LSN_for_page);
-extern void pagecache_unlock(PAGECACHE *pagecache,
+extern void pagecache_unlock_by_link(PAGECACHE *pagecache,
                                      PAGECACHE_PAGE_LINK *link,
                                      enum pagecache_page_lock lock,
                                      enum pagecache_page_pin pin,
                                      LSN first_REDO_LSN_for_page);
-extern void pagecache_unpin_page(PAGECACHE *pagecache,
+extern void pagecache_unpin(PAGECACHE *pagecache,
                             PAGECACHE_FILE *file,
                             pgcache_page_no_t pageno);
-extern void pagecache_unpin(PAGECACHE *pagecache,
+extern void pagecache_unpin_by_link(PAGECACHE *pagecache,
                                     PAGECACHE_PAGE_LINK *link);
 extern int flush_pagecache_blocks(PAGECACHE *keycache,
                                   PAGECACHE_FILE *file,
                                   enum flush_type type);
-extern my_bool pagecache_delete_page(PAGECACHE *pagecache,
+extern my_bool pagecache_delete(PAGECACHE *pagecache,
                                 PAGECACHE_FILE *file,
                                 pgcache_page_no_t pageno,
                                 enum pagecache_page_lock lock,

storage/maria/unittest/mf_pagecache_consist.c

@@ -135,7 +135,7 @@ err:
   DBUG_PRINT("err", ("try to flush"));
   if (page_locked)
   {
-    pagecache_delete_page(&pagecache, &file1, page_no,
+    pagecache_delete(&pagecache, &file1, page_no,
                      PAGECACHE_LOCK_LEFT_WRITELOCKED, 1);
   }
   else

storage/maria/unittest/mf_pagecache_single.c

@@ -231,7 +231,7 @@ int simple_pin_test()
   ok((res= test(test_file(file1, file1_name, PAGE_SIZE*2, PAGE_SIZE*2,
                            simple_pin_test_file1))),
      "Simple pin page file with pin");
-  pagecache_unlock_page(&pagecache,
+  pagecache_unlock(&pagecache,
                    &file1,
                    0,
                    PAGECACHE_LOCK_READ_UNLOCK,
@@ -282,7 +282,7 @@ int simple_delete_forget_test()
                   PAGECACHE_PIN_LEFT_UNPINNED,
                   PAGECACHE_WRITE_DELAY,
                   0);
-  pagecache_delete_page(&pagecache, &file1, 0,
+  pagecache_delete(&pagecache, &file1, 0,
                    PAGECACHE_LOCK_WRITE, 0);
   flush_pagecache_blocks(&pagecache, &file1, FLUSH_FORCE_WRITE);
   ok((res= test(test_file(file1, file1_name, PAGE_SIZE, PAGE_SIZE,
@@ -324,7 +324,7 @@ int simple_delete_flush_test()
                   PAGECACHE_PIN_LEFT_PINNED,
                   PAGECACHE_WRITE_DELAY,
                   0);
-  pagecache_delete_page(&pagecache, &file1, 0,
+  pagecache_delete(&pagecache, &file1, 0,
                    PAGECACHE_LOCK_LEFT_WRITELOCKED, 1);
   flush_pagecache_blocks(&pagecache, &file1, FLUSH_FORCE_WRITE);
   ok((res= test(test_file(file1, file1_name, PAGE_SIZE, PAGE_SIZE,