[PATCH v18 42/80] c/r: export shmem_getpage() to support shared memory

Oren Laadan
2009-09-24T00:30:23Z

Export functionality to retrieve specific pages from shared memory
given an inode in shmem-fs; this will be used in the next two patches
to provide support for c/r of shared memory.

mm/shmem.c:
- shmem_getpage() and 'enum sgp_type' moved to linux/mm.h

Signed-off-by: Oren Laadan <orenl@cs.columbia.edu>
---
include/linux/mm.h | 11 +++++++++++
mm/shmem.c | 15 ++-------------
2 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 0d0c46b..b565a82 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -327,6 +327,17 @@ void put_pages_list(struct list_head *pages);

void split_page(struct page *page, unsigned int order);

+/* Flag allocation requirements to shmem_getpage and shmem_swp_alloc */
+enum sgp_type {
+ SGP_READ, /* don't exceed i_size, don't allocate page */
+ SGP_CACHE, /* don't exceed i_size, may allocate page */
+ SGP_DIRTY, /* like SGP_CACHE, but set new page dirty */
+ SGP_WRITE, /* may exceed i_size, may allocate page */
+};
+
+extern int shmem_getpage(struct inode *inode, unsigned long idx,
+ struct page **pagep, enum sgp_type sgp, int *type);
+
/*
* Compound pages have a destructor function. Provide a
* prototype for that function and accessor functions.
diff --git a/mm/shmem.c b/mm/shmem.c
index d713239..d80532b 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -99,14 +99,6 @@ static struct vfsmount *shm_mnt;
/* Pretend that each entry is of this size in directory's i_size */
#define BOGO_DIRENT_SIZE 20

-/* Flag allocation requirements to shmem_getpage and shmem_swp_alloc */
-enum sgp_type {
- SGP_READ, /* don't exceed i_size, don't allocate page */
- SGP_CACHE, /* don't exceed i_size, may allocate page */
- SGP_DIRTY, /* like SGP_CACHE, but set new page dirty */
- SGP_WRITE, /* may exceed i_size, may allocate page */
-};
-
#ifdef CONFIG_TMPFS
static unsigned long shmem_default_max_blocks(void)
{
@@ -119,9 +111,6 @@ static unsigned long shmem_default_max_inodes(void)
}
#endif

-static int shmem_getpage(struct inode *inode, unsigned long idx,
- struct page **pagep, enum sgp_type sgp, int *type);
-
static inline struct page *shmem_dir_alloc(gfp_t gfp_mask)
{
/*
@@ -1202,8 +1191,8 @@ static inline struct mempolicy *shmem_get_sbmpol(struct shmem_sb_info *sbinfo)
* vm. If we swap it in we mark it dirty since we also free the swap
* entry since a page cannot live in both the swap and page cache
*/
-static int shmem_getpage(struct inode *inode, unsigned long idx,
- struct page **pagep, enum sgp_type sgp, int *type)
+int shmem_getpage(struct inode *inode, unsigned long idx,
+ struct page **pagep, enum sgp_type sgp, int *type)
{
struct address_space *mapping = inode->i_mapping;
struct shmem_inode_info *info = SHMEM_I(inode);
--
1.6.0.4