Merge tag 'for_v4.20-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

[sfrench/cifs-2.6.git] / include / linux / fs.h

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 897eae8faee1b04f12fe8cbebbaae2b4505a771d..8252df30b9a16afe53c269b912b47e17edac7b41 100644 (file)
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -403,24 +403,40 @@ int pagecache_write_end(struct file *, struct address_space *mapping,
                                loff_t pos, unsigned len, unsigned copied,
                                struct page *page, void *fsdata);
 
+/**
+ * struct address_space - Contents of a cacheable, mappable object.
+ * @host: Owner, either the inode or the block_device.
+ * @i_pages: Cached pages.
+ * @gfp_mask: Memory allocation flags to use for allocating pages.
+ * @i_mmap_writable: Number of VM_SHARED mappings.
+ * @i_mmap: Tree of private and shared mappings.
+ * @i_mmap_rwsem: Protects @i_mmap and @i_mmap_writable.
+ * @nrpages: Number of page entries, protected by the i_pages lock.
+ * @nrexceptional: Shadow or DAX entries, protected by the i_pages lock.
+ * @writeback_index: Writeback starts here.
+ * @a_ops: Methods.
+ * @flags: Error bits and flags (AS_*).
+ * @wb_err: The most recent error which has occurred.
+ * @private_lock: For use by the owner of the address_space.
+ * @private_list: For use by the owner of the address_space.
+ * @private_data: For use by the owner of the address_space.
+ */
 struct address_space {
-       struct inode            *host;          /* owner: inode, block_device */
-       struct radix_tree_root  i_pages;        /* cached pages */
-       atomic_t                i_mmap_writable;/* count VM_SHARED mappings */
-       struct rb_root_cached   i_mmap;         /* tree of private and shared mappings */
-       struct rw_semaphore     i_mmap_rwsem;   /* protect tree, count, list */
-       /* Protected by the i_pages lock */
-       unsigned long           nrpages;        /* number of total pages */
-       /* number of shadow or DAX exceptional entries */
+       struct inode            *host;
+       struct xarray           i_pages;
+       gfp_t                   gfp_mask;
+       atomic_t                i_mmap_writable;
+       struct rb_root_cached   i_mmap;
+       struct rw_semaphore     i_mmap_rwsem;
+       unsigned long           nrpages;
        unsigned long           nrexceptional;
-       pgoff_t                 writeback_index;/* writeback starts here */
-       const struct address_space_operations *a_ops;   /* methods */
-       unsigned long           flags;          /* error bits */
-       spinlock_t              private_lock;   /* for use by the address_space */
-       gfp_t                   gfp_mask;       /* implicit gfp mask for allocations */
-       struct list_head        private_list;   /* for use by the address_space */
-       void                    *private_data;  /* ditto */
+       pgoff_t                 writeback_index;
+       const struct address_space_operations *a_ops;
+       unsigned long           flags;
        errseq_t                wb_err;
+       spinlock_t              private_lock;
+       struct list_head        private_list;
+       void                    *private_data;
 } __attribute__((aligned(sizeof(long)))) __randomize_layout;
        /*
         * On most architectures that alignment is already the case; but
@@ -467,15 +483,18 @@ struct block_device {
        struct mutex            bd_fsfreeze_mutex;
 } __randomize_layout;
 
+/* XArray tags, for tagging dirty and writeback pages in the pagecache. */
+#define PAGECACHE_TAG_DIRTY    XA_MARK_0
+#define PAGECACHE_TAG_WRITEBACK        XA_MARK_1
+#define PAGECACHE_TAG_TOWRITE  XA_MARK_2
+
 /*
- * Radix-tree tags, for tagging dirty and writeback pages within the pagecache
- * radix trees
+ * Returns true if any of the pages in the mapping are marked with the tag.
  */
-#define PAGECACHE_TAG_DIRTY    0
-#define PAGECACHE_TAG_WRITEBACK        1
-#define PAGECACHE_TAG_TOWRITE  2
-
-int mapping_tagged(struct address_space *mapping, int tag);
+static inline bool mapping_tagged(struct address_space *mapping, xa_mark_t tag)
+{
+       return xa_marked(&mapping->i_pages, tag);
+}
 
 static inline void i_mmap_lock_write(struct address_space *mapping)
 {
@@ -1393,17 +1412,26 @@ struct super_block {
 
        struct sb_writers       s_writers;
 
+       /*
+        * Keep s_fs_info, s_time_gran, s_fsnotify_mask, and
+        * s_fsnotify_marks together for cache efficiency. They are frequently
+        * accessed and rarely modified.
+        */
+       void                    *s_fs_info;     /* Filesystem private info */
+
+       /* Granularity of c/m/atime in ns (cannot be worse than a second) */
+       u32                     s_time_gran;
+#ifdef CONFIG_FSNOTIFY
+       __u32                   s_fsnotify_mask;
+       struct fsnotify_mark_connector __rcu    *s_fsnotify_marks;
+#endif
+
        char                    s_id[32];       /* Informational name */
        uuid_t                  s_uuid;         /* UUID */
 
-       void                    *s_fs_info;     /* Filesystem private info */
        unsigned int            s_max_links;
        fmode_t                 s_mode;
 
-       /* Granularity of c/m/atime in ns.
-          Cannot be worse than a second */
-       u32                s_time_gran;
-
        /*
         * The next field is for VFS *only*. No filesystems have any business
         * even looking at it. You had been warned.
@@ -1428,6 +1456,9 @@ struct super_block {
        /* Number of inodes with nlink == 0 but still referenced */
        atomic_long_t s_remove_count;
 
+       /* Pending fsnotify inode refs */
+       atomic_long_t s_fsnotify_inode_refs;
+
        /* Being remounted read-only */
        int s_readonly_remount;