Simplify BDI integration

[zfs.git] / include / linux / vfs_compat.h

diff --git a/include/linux/vfs_compat.h b/include/linux/vfs_compat.h
index dce2b6f..825a7fd 100644 (file)
--- a/include/linux/vfs_compat.h
+++ b/include/linux/vfs_compat.h
@@ -41,4 +41,57 @@ insert_inode_locked(struct inode *ip)
 }
 #endif /* HAVE_INSERT_INODE_LOCKED */
 
+/*
+ * 2.6.35 API change,
+ * Add truncate_setsize() if it is not exported by the Linux kernel.
+ *
+ * Truncate the inode and pages associated with the inode. The pages are
+ * unmapped and removed from cache.
+ */
+#ifndef HAVE_TRUNCATE_SETSIZE
+static inline void
+truncate_setsize(struct inode *ip, loff_t new)
+{
+       struct address_space *mapping = ip->i_mapping;
+
+       i_size_write(ip, new);
+
+       unmap_mapping_range(mapping, new + PAGE_SIZE - 1, 0, 1);
+       truncate_inode_pages(mapping, new);
+       unmap_mapping_range(mapping, new + PAGE_SIZE - 1, 0, 1);
+}
+#endif /* HAVE_TRUNCATE_SETSIZE */
+
+#if defined(HAVE_BDI) && !defined(HAVE_BDI_SETUP_AND_REGISTER)
+/*
+ * 2.6.34 API change,
+ * Add bdi_setup_and_register() function if not yet provided by kernel.
+ * It is used to quickly initialize and register a BDI for the filesystem.
+ */
+extern atomic_long_t zfs_bdi_seq;
+
+static inline int
+bdi_setup_and_register(struct backing_dev_info *bdi,char *name,unsigned int cap)
+{
+       char tmp[32];
+       int error;
+
+       bdi->name = name;
+       bdi->capabilities = cap;
+       error = bdi_init(bdi);
+       if (error)
+               return (error);
+
+       sprintf(tmp, "%.28s%s", name, "-%d");
+       error = bdi_register(bdi, NULL, tmp,
+           atomic_long_inc_return(&zfs_bdi_seq));
+       if (error) {
+               bdi_destroy(bdi);
+               return (error);
+       }
+
+       return (error);
+}
+#endif /* HAVE_BDI && !HAVE_BDI_SETUP_AND_REGISTER */
+
 #endif /* _ZFS_VFS_H */