memory unplug: page isolation

[linux-2.6] / include / linux / fs.h

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 86ce27c725540244d0e2c09303d67b169a8848aa..f70d52c46617b053b301e804a446ed83b3ee92b3 100644 (file)
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -381,7 +381,7 @@ struct iattr {
  *                     trying again.  The aop will be taking reasonable
  *                     precautions not to livelock.  If the caller held a page
  *                     reference, it should drop it before retrying.  Returned
- *                     by readpage(), prepare_write(), and commit_write().
+ *                     by readpage().
  *
  * address_space_operation functions return these large constants to indicate
  * special semantics to the caller.  These are much larger than the bytes in a
@@ -394,6 +394,9 @@ enum positive_aop_returns {
        AOP_TRUNCATED_PAGE      = 0x80001,
 };
 
+#define AOP_FLAG_UNINTERRUPTIBLE       0x0001 /* will not do a short write */
+#define AOP_FLAG_CONT_EXPAND           0x0002 /* called from cont_expand */
+
 /*
  * oh the beauties of C type declarations.
  */
@@ -413,7 +416,7 @@ size_t iov_iter_copy_from_user_atomic(struct page *page,
 size_t iov_iter_copy_from_user(struct page *page,
                struct iov_iter *i, unsigned long offset, size_t bytes);
 void iov_iter_advance(struct iov_iter *i, size_t bytes);
-int iov_iter_fault_in_readable(struct iov_iter *i);
+int iov_iter_fault_in_readable(struct iov_iter *i, size_t bytes);
 size_t iov_iter_single_seg_count(struct iov_iter *i);
 
 static inline void iov_iter_init(struct iov_iter *i,
@@ -454,6 +457,14 @@ struct address_space_operations {
         */
        int (*prepare_write)(struct file *, struct page *, unsigned, unsigned);
        int (*commit_write)(struct file *, struct page *, unsigned, unsigned);
+
+       int (*write_begin)(struct file *, struct address_space *mapping,
+                               loff_t pos, unsigned len, unsigned flags,
+                               struct page **pagep, void **fsdata);
+       int (*write_end)(struct file *, struct address_space *mapping,
+                               loff_t pos, unsigned len, unsigned copied,
+                               struct page *page, void *fsdata);
+
        /* Unfortunately this kludge is needed for FIBMAP. Don't use it */
        sector_t (*bmap)(struct address_space *, sector_t);
        void (*invalidatepage) (struct page *, unsigned long);
@@ -468,6 +479,18 @@ struct address_space_operations {
        int (*launder_page) (struct page *);
 };
 
+/*
+ * pagecache_write_begin/pagecache_write_end must be used by general code
+ * to write into the pagecache.
+ */
+int pagecache_write_begin(struct file *, struct address_space *mapping,
+                               loff_t pos, unsigned len, unsigned flags,
+                               struct page **pagep, void **fsdata);
+
+int pagecache_write_end(struct file *, struct address_space *mapping,
+                               loff_t pos, unsigned len, unsigned copied,
+                               struct page *page, void *fsdata);
+
 struct backing_dev_info;
 struct address_space {
        struct inode            *host;          /* owner: inode, block_device */
@@ -1866,6 +1889,12 @@ extern int simple_prepare_write(struct file *file, struct page *page,
                        unsigned offset, unsigned to);
 extern int simple_commit_write(struct file *file, struct page *page,
                                unsigned offset, unsigned to);
+extern int simple_write_begin(struct file *file, struct address_space *mapping,
+                       loff_t pos, unsigned len, unsigned flags,
+                       struct page **pagep, void **fsdata);
+extern int simple_write_end(struct file *file, struct address_space *mapping,
+                       loff_t pos, unsigned len, unsigned copied,
+                       struct page *page, void *fsdata);
 
 extern struct dentry *simple_lookup(struct inode *, struct dentry *, struct nameidata *);
 extern ssize_t generic_read_dir(struct file *, char __user *, size_t, loff_t *);