Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[mv-sheeva.git] / fs / btrfs / struct-funcs.c

diff --git a/fs/btrfs/struct-funcs.c b/fs/btrfs/struct-funcs.c
index bc1f6ad18442bc728a10e9919b91162af1b60b4d..c6ffa58124192a9e069b1464d863b33300bcf6e9 100644 (file)
--- a/fs/btrfs/struct-funcs.c
+++ b/fs/btrfs/struct-funcs.c
@@ -44,8 +44,9 @@
 #define BTRFS_SETGET_FUNCS(name, type, member, bits)                   \
 u##bits btrfs_##name(struct extent_buffer *eb, type *s);               \
 void btrfs_set_##name(struct extent_buffer *eb, type *s, u##bits val); \
-u##bits btrfs_##name(struct extent_buffer *eb,                         \
-                                  type *s)                             \
+void btrfs_set_token_##name(struct extent_buffer *eb, type *s, u##bits val, struct btrfs_map_token *token);    \
+u##bits btrfs_token_##name(struct extent_buffer *eb,                           \
+                          type *s, struct btrfs_map_token *token)      \
 {                                                                      \
        unsigned long part_offset = (unsigned long)s;                   \
        unsigned long offset = part_offset + offsetof(type, member);    \
@@ -54,9 +55,18 @@ u##bits btrfs_##name(struct extent_buffer *eb,                               \
        char *kaddr;                                            \
        unsigned long map_start;                                \
        unsigned long map_len;                                  \
+       unsigned long mem_len = sizeof(((type *)0)->member);    \
        u##bits res;                                            \
+       if (token && token->kaddr && token->offset <= offset && \
+           token->eb == eb &&                                  \
+          (token->offset + PAGE_CACHE_SIZE >= offset + mem_len)) { \
+               kaddr = token->kaddr;                           \
+               p = (type *)(kaddr + part_offset - token->offset);  \
+               res = le##bits##_to_cpu(p->member);             \
+               return res;                                     \
+       }                                                       \
        err = map_private_extent_buffer(eb, offset,             \
-                       sizeof(((type *)0)->member),            \
+                       mem_len,                                \
                        &kaddr, &map_start, &map_len);          \
        if (err) {                                              \
                __le##bits leres;                               \
@@ -65,10 +75,15 @@ u##bits btrfs_##name(struct extent_buffer *eb,                              \
        }                                                       \
        p = (type *)(kaddr + part_offset - map_start);          \
        res = le##bits##_to_cpu(p->member);                     \
+       if (token) {                                            \
+               token->kaddr = kaddr;                           \
+               token->offset = map_start;                      \
+               token->eb = eb;                                 \
+       }                                                       \
        return res;                                             \
 }                                                                      \
-void btrfs_set_##name(struct extent_buffer *eb,                                \
-                                   type *s, u##bits val)               \
+void btrfs_set_token_##name(struct extent_buffer *eb,                          \
+                           type *s, u##bits val, struct btrfs_map_token *token)                \
 {                                                                      \
        unsigned long part_offset = (unsigned long)s;                   \
        unsigned long offset = part_offset + offsetof(type, member);    \
@@ -77,8 +92,17 @@ void btrfs_set_##name(struct extent_buffer *eb,                              \
        char *kaddr;                                            \
        unsigned long map_start;                                \
        unsigned long map_len;                                  \
+       unsigned long mem_len = sizeof(((type *)0)->member);    \
+       if (token && token->kaddr && token->offset <= offset && \
+           token->eb == eb &&                                  \
+          (token->offset + PAGE_CACHE_SIZE >= offset + mem_len)) { \
+               kaddr = token->kaddr;                           \
+               p = (type *)(kaddr + part_offset - token->offset);  \
+               p->member = cpu_to_le##bits(val);               \
+               return;                                         \
+       }                                                       \
        err = map_private_extent_buffer(eb, offset,             \
-                       sizeof(((type *)0)->member),            \
+                       mem_len,                                \
                        &kaddr, &map_start, &map_len);          \
        if (err) {                                              \
                __le##bits val2;                                \
@@ -88,7 +112,22 @@ void btrfs_set_##name(struct extent_buffer *eb,                             \
        }                                                       \
        p = (type *)(kaddr + part_offset - map_start);          \
        p->member = cpu_to_le##bits(val);                       \
-}
+       if (token) {                                            \
+               token->kaddr = kaddr;                           \
+               token->offset = map_start;                      \
+               token->eb = eb;                                 \
+       }                                                       \
+}                                                              \
+void btrfs_set_##name(struct extent_buffer *eb,                        \
+                     type *s, u##bits val)                     \
+{                                                              \
+       btrfs_set_token_##name(eb, s, val, NULL);               \
+}                                                              \
+u##bits btrfs_##name(struct extent_buffer *eb,                 \
+                     type *s)                                  \
+{                                                              \
+       return btrfs_token_##name(eb, s, NULL);                 \
+}                                                              \
 
 #include "ctree.h"