Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 updates from Ted Ts'o:
 "Some locking and page fault bug fixes from Jan Kara, some ext4
  encryption fixes from me, and Li Xi's Project Quota commits"

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  fs: clean up the flags definition in uapi/linux/fs.h
  ext4: add FS_IOC_FSSETXATTR/FS_IOC_FSGETXATTR interface support
  ext4: add project quota support
  ext4: adds project ID support
  ext4 crypto: simplify interfaces to directory entry insert functions
  ext4 crypto: add missing locking for keyring_key access
  ext4: use pre-zeroed blocks for DAX page faults
  ext4: implement allocation of pre-zeroed blocks
  ext4: provide ext4_issue_zeroout()
  ext4: get rid of EXT4_GET_BLOCKS_NO_LOCK flag
  ext4: document lock ordering
  ext4: fix races of writeback with punch hole and zero range
  ext4: fix races between buffered IO and collapse / insert range
  ext4: move unlocked dio protection from ext4_alloc_file_blocks()
  ext4: fix races between page faults and hole punching

include/uapi/linux/fs.h

@@ -2,8 +2,11 @@
 #define _UAPI_LINUX_FS_H
 
 /*
- * This file has definitions for some important file table
- * structures etc.
+ * This file has definitions for some important file table structures
+ * and constants and structures used by various generic file system
+ * ioctl's.  Please do not make any changes in this file before
+ * sending patches for review to linux-fsdevel@vger.kernel.org and
+ * linux-api@vger.kernel.org.
  */
 
 #include <linux/limits.h>
@@ -246,6 +249,23 @@ struct fsxattr {
 
 /*
  * Inode flags (FS_IOC_GETFLAGS / FS_IOC_SETFLAGS)
+ *
+ * Note: for historical reasons, these flags were originally used and
+ * defined for use by ext2/ext3, and then other file systems started
+ * using these flags so they wouldn't need to write their own version
+ * of chattr/lsattr (which was shipped as part of e2fsprogs).  You
+ * should think twice before trying to use these flags in new
+ * contexts, or trying to assign these flags, since they are used both
+ * as the UAPI and the on-disk encoding for ext2/3/4.  Also, we are
+ * almost out of 32-bit flags.  :-)
+ *
+ * We have recently hoisted FS_IOC_FSGETXATTR / FS_IOC_FSSETXATTR from
+ * XFS to the generic FS level interface.  This uses a structure that
+ * has padding and hence has more room to grow, so it may be more
+ * appropriate for many new use cases.
+ *
+ * Please do not change these flags or interfaces before checking with
+ * linux-fsdevel@vger.kernel.org and linux-api@vger.kernel.org.
  */
 #define	FS_SECRM_FL			0x00000001 /* Secure deletion */
 #define	FS_UNRM_FL			0x00000002 /* Undelete */
@@ -259,8 +279,8 @@ struct fsxattr {
 #define FS_DIRTY_FL			0x00000100
 #define FS_COMPRBLK_FL			0x00000200 /* One or more compressed clusters */
 #define FS_NOCOMP_FL			0x00000400 /* Don't compress */
-#define FS_ECOMPR_FL			0x00000800 /* Compression error */
 /* End compression flags --- maybe not all used */
+#define FS_ENCRYPT_FL			0x00000800 /* Encrypted file */
 #define FS_BTREE_FL			0x00001000 /* btree format dir */
 #define FS_INDEX_FL			0x00001000 /* hash-indexed directory */
 #define FS_IMAGIC_FL			0x00002000 /* AFS directory */
@@ -268,9 +288,12 @@ struct fsxattr {
 #define FS_NOTAIL_FL			0x00008000 /* file tail should not be merged */
 #define FS_DIRSYNC_FL			0x00010000 /* dirsync behaviour (directories only) */
 #define FS_TOPDIR_FL			0x00020000 /* Top of directory hierarchies*/
+#define FS_HUGE_FILE_FL			0x00040000 /* Reserved for ext4 */
 #define FS_EXTENT_FL			0x00080000 /* Extents */
-#define FS_DIRECTIO_FL			0x00100000 /* Use direct i/o */
+#define FS_EA_INODE_FL			0x00200000 /* Inode used for large EA */
+#define FS_EOFBLOCKS_FL			0x00400000 /* Reserved for ext4 */
 #define FS_NOCOW_FL			0x00800000 /* Do not cow file */
+#define FS_INLINE_DATA_FL		0x10000000 /* Reserved for ext4 */
 #define FS_PROJINHERIT_FL		0x20000000 /* Create with parents projid */
 #define FS_RESERVED_FL			0x80000000 /* reserved for ext2 lib */