[PATCH] swsusp: Introduce some helpful constants

Introduce some constants that hopefully will help improve the readability of
code in kernel/power/snapshot.c.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 15 insertions, 9 deletions

diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index 1d276b3ae152..d0d691f976d8 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -167,6 +167,11 @@ static inline int restore_highmem(void) {return 0;}
  *      and we count them using unsafe_pages
  */
 
+#define PG_ANY          0
+#define PG_SAFE         1
+#define PG_UNSAFE_CLEAR 1
+#define PG_UNSAFE_KEEP  0
+
 static unsigned int unsafe_pages;
 
 static void *alloc_image_page(gfp_t gfp_mask, int safe_needed)
@@ -190,7 +195,7 @@ static void *alloc_image_page(gfp_t gfp_mask, int safe_needed)
 
 unsigned long get_safe_page(gfp_t gfp_mask)
 {
-        return (unsigned long)alloc_image_page(gfp_mask, 1);
+        return (unsigned long)alloc_image_page(gfp_mask, PG_SAFE);
 }
 
 /**
@@ -381,7 +386,7 @@ static struct pbe *alloc_pagedir(unsigned int nr_pages, gfp_t gfp_mask,
         pbe = pblist;
         for (num = PBES_PER_PAGE; num < nr_pages; num += PBES_PER_PAGE) {
                 if (!pbe) {
-                        free_pagedir(pblist, 1);
+                        free_pagedir(pblist, PG_UNSAFE_CLEAR);
                         return NULL;
                 }
                 pbe += PB_PAGE_SKIP;
@@ -458,12 +463,13 @@ static struct pbe *swsusp_alloc(unsigned int nr_pages)
 {
         struct pbe *pblist;
 
-        if (!(pblist = alloc_pagedir(nr_pages, GFP_ATOMIC | __GFP_COLD, 0))) {
+        pblist = alloc_pagedir(nr_pages, GFP_ATOMIC | __GFP_COLD, PG_ANY);
+        if (!pblist) {
                 printk(KERN_ERR "suspend: Allocating pagedir failed.\n");
                 return NULL;
         }
 
-        if (alloc_data_pages(pblist, GFP_ATOMIC | __GFP_COLD, 0)) {
+        if (alloc_data_pages(pblist, GFP_ATOMIC | __GFP_COLD, PG_ANY)) {
                 printk(KERN_ERR "suspend: Allocating image pages failed.\n");
                 swsusp_free();
                 return NULL;
@@ -575,7 +581,7 @@ int snapshot_read_next(struct snapshot_handle *handle, size_t count)
                 return 0;
         if (!buffer) {
                 /* This makes the buffer be freed by swsusp_free() */
-                buffer = alloc_image_page(GFP_ATOMIC, 0);
+                buffer = alloc_image_page(GFP_ATOMIC, PG_ANY);
                 if (!buffer)
                         return -ENOMEM;
         }
@@ -688,7 +694,7 @@ static int load_header(struct snapshot_handle *handle,
 
         error = check_header(info);
         if (!error) {
-                pblist = alloc_pagedir(info->image_pages, GFP_ATOMIC, 0);
+                pblist = alloc_pagedir(info->image_pages, GFP_ATOMIC, PG_ANY);
                 if (!pblist)
                         return -ENOMEM;
                 restore_pblist = pblist;
@@ -746,10 +752,10 @@ static int prepare_image(struct snapshot_handle *handle)
         p = restore_pblist;
         error = mark_unsafe_pages(p);
         if (!error) {
-                pblist = alloc_pagedir(nr_pages, GFP_ATOMIC, 1);
+                pblist = alloc_pagedir(nr_pages, GFP_ATOMIC, PG_SAFE);
                 if (pblist)
                         copy_page_backup_list(pblist, p);
-                free_pagedir(p, 0);
+                free_pagedir(p, PG_UNSAFE_KEEP);
                 if (!pblist)
                         error = -ENOMEM;
         }
@@ -840,7 +846,7 @@ int snapshot_write_next(struct snapshot_handle *handle, size_t count)
                 return 0;
         if (!buffer) {
                 /* This makes the buffer be freed by swsusp_free() */
-                buffer = alloc_image_page(GFP_ATOMIC, 0);
+                buffer = alloc_image_page(GFP_ATOMIC, PG_ANY);
                 if (!buffer)
                         return -ENOMEM;
         }