ext2: get rid of most mentions of XIP in ext2

To help people transition, accept the 'xip' mount option (and report it in
/proc/mounts), but print a message encouraging people to switch over to
the 'dax' option.

Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andreas Dilger <andreas.dilger@intel.com>
Cc: Boaz Harrosh <boaz@plexistor.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/Documentation/filesystems/ext2.txt b/Documentation/filesystems/ext2.txt
index 67639f9..b971456 100644
--- a/Documentation/filesystems/ext2.txt
+++ b/Documentation/filesystems/ext2.txt
@@ -20,6 +20,9 @@
 check=none, nocheck	(*)	Don't do extra checking of bitmaps on mount
 				(check=normal and check=strict options removed)
 
+dax				Use direct access (no page cache).  See
+				Documentation/filesystems/dax.txt.
+
 debug				Extra debugging information is sent to the
 				kernel syslog.  Useful for developers.
 
@@ -56,8 +59,6 @@
 
 nobh				Do not attach buffer_heads to file pagecache.
 
-xip				Use execute in place (no caching) if possible
-
 grpquota,noquota,quota,usrquota	Quota options are silently ignored by ext2.
 
 
diff --git a/fs/ext2/ext2.h b/fs/ext2/ext2.h
index ab9b3ec..678f9ab 100644
--- a/fs/ext2/ext2.h
+++ b/fs/ext2/ext2.h
@@ -380,14 +380,15 @@
 #define EXT2_MOUNT_NO_UID32		0x000200  /* Disable 32-bit UIDs */
 #define EXT2_MOUNT_XATTR_USER		0x004000  /* Extended user attributes */
 #define EXT2_MOUNT_POSIX_ACL		0x008000  /* POSIX Access Control Lists */
-#ifdef CONFIG_FS_DAX
-#define EXT2_MOUNT_XIP			0x010000  /* Execute in place */
-#else
-#define EXT2_MOUNT_XIP			0
-#endif
+#define EXT2_MOUNT_XIP			0x010000  /* Obsolete, use DAX */
 #define EXT2_MOUNT_USRQUOTA		0x020000  /* user quota */
 #define EXT2_MOUNT_GRPQUOTA		0x040000  /* group quota */
 #define EXT2_MOUNT_RESERVATION		0x080000  /* Preallocation */
+#ifdef CONFIG_FS_DAX
+#define EXT2_MOUNT_DAX			0x100000  /* Direct Access */
+#else
+#define EXT2_MOUNT_DAX			0
+#endif
 
 
 #define clear_opt(o, opt)		o &= ~EXT2_MOUNT_##opt
@@ -792,7 +793,7 @@
 		      int datasync);
 extern const struct inode_operations ext2_file_inode_operations;
 extern const struct file_operations ext2_file_operations;
-extern const struct file_operations ext2_xip_file_operations;
+extern const struct file_operations ext2_dax_file_operations;
 
 /* inode.c */
 extern const struct address_space_operations ext2_aops;
diff --git a/fs/ext2/file.c b/fs/ext2/file.c
index de8174d..e317017 100644
--- a/fs/ext2/file.c
+++ b/fs/ext2/file.c
@@ -109,7 +109,7 @@
 };
 
 #ifdef CONFIG_FS_DAX
-const struct file_operations ext2_xip_file_operations = {
+const struct file_operations ext2_dax_file_operations = {
 	.llseek		= generic_file_llseek,
 	.read		= new_sync_read,
 	.write		= new_sync_write,
diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
index 034fd42..6434bc0 100644
--- a/fs/ext2/inode.c
+++ b/fs/ext2/inode.c
@@ -1286,7 +1286,7 @@
 		inode->i_flags |= S_NOATIME;
 	if (flags & EXT2_DIRSYNC_FL)
 		inode->i_flags |= S_DIRSYNC;
-	if (test_opt(inode->i_sb, XIP))
+	if (test_opt(inode->i_sb, DAX))
 		inode->i_flags |= S_DAX;
 }
 
@@ -1388,9 +1388,9 @@
 
 	if (S_ISREG(inode->i_mode)) {
 		inode->i_op = &ext2_file_inode_operations;
-		if (test_opt(inode->i_sb, XIP)) {
+		if (test_opt(inode->i_sb, DAX)) {
 			inode->i_mapping->a_ops = &ext2_aops;
-			inode->i_fop = &ext2_xip_file_operations;
+			inode->i_fop = &ext2_dax_file_operations;
 		} else if (test_opt(inode->i_sb, NOBH)) {
 			inode->i_mapping->a_ops = &ext2_nobh_aops;
 			inode->i_fop = &ext2_file_operations;
diff --git a/fs/ext2/namei.c b/fs/ext2/namei.c
index 0db888c..148f6e3 100644
--- a/fs/ext2/namei.c
+++ b/fs/ext2/namei.c
@@ -104,9 +104,9 @@
 		return PTR_ERR(inode);
 
 	inode->i_op = &ext2_file_inode_operations;
-	if (test_opt(inode->i_sb, XIP)) {
+	if (test_opt(inode->i_sb, DAX)) {
 		inode->i_mapping->a_ops = &ext2_aops;
-		inode->i_fop = &ext2_xip_file_operations;
+		inode->i_fop = &ext2_dax_file_operations;
 	} else if (test_opt(inode->i_sb, NOBH)) {
 		inode->i_mapping->a_ops = &ext2_nobh_aops;
 		inode->i_fop = &ext2_file_operations;
@@ -125,9 +125,9 @@
 		return PTR_ERR(inode);
 
 	inode->i_op = &ext2_file_inode_operations;
-	if (test_opt(inode->i_sb, XIP)) {
+	if (test_opt(inode->i_sb, DAX)) {
 		inode->i_mapping->a_ops = &ext2_aops;
-		inode->i_fop = &ext2_xip_file_operations;
+		inode->i_fop = &ext2_dax_file_operations;
 	} else if (test_opt(inode->i_sb, NOBH)) {
 		inode->i_mapping->a_ops = &ext2_nobh_aops;
 		inode->i_fop = &ext2_file_operations;
diff --git a/fs/ext2/super.c b/fs/ext2/super.c
index 5f029d8..d0e746e 100644
--- a/fs/ext2/super.c
+++ b/fs/ext2/super.c
@@ -294,6 +294,8 @@
 #ifdef CONFIG_FS_DAX
 	if (sbi->s_mount_opt & EXT2_MOUNT_XIP)
 		seq_puts(seq, ",xip");
+	if (sbi->s_mount_opt & EXT2_MOUNT_DAX)
+		seq_puts(seq, ",dax");
 #endif
 
 	if (!test_opt(sb, RESERVATION))
@@ -402,7 +404,7 @@
 	Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic,
 	Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug,
 	Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr,
-	Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota,
+	Opt_acl, Opt_noacl, Opt_xip, Opt_dax, Opt_ignore, Opt_err, Opt_quota,
 	Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation
 };
 
@@ -431,6 +433,7 @@
 	{Opt_acl, "acl"},
 	{Opt_noacl, "noacl"},
 	{Opt_xip, "xip"},
+	{Opt_dax, "dax"},
 	{Opt_grpquota, "grpquota"},
 	{Opt_ignore, "noquota"},
 	{Opt_quota, "quota"},
@@ -558,10 +561,14 @@
 			break;
 #endif
 		case Opt_xip:
+			ext2_msg(sb, KERN_INFO, "use dax instead of xip");
+			set_opt(sbi->s_mount_opt, XIP);
+			/* Fall through */
+		case Opt_dax:
 #ifdef CONFIG_FS_DAX
-			set_opt (sbi->s_mount_opt, XIP);
+			set_opt(sbi->s_mount_opt, DAX);
 #else
-			ext2_msg(sb, KERN_INFO, "xip option not supported");
+			ext2_msg(sb, KERN_INFO, "dax option not supported");
 #endif
 			break;
 
@@ -905,15 +912,15 @@
 
 	blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
 
-	if (sbi->s_mount_opt & EXT2_MOUNT_XIP) {
+	if (sbi->s_mount_opt & EXT2_MOUNT_DAX) {
 		if (blocksize != PAGE_SIZE) {
 			ext2_msg(sb, KERN_ERR,
-					"error: unsupported blocksize for xip");
+					"error: unsupported blocksize for dax");
 			goto failed_mount;
 		}
 		if (!sb->s_bdev->bd_disk->fops->direct_access) {
 			ext2_msg(sb, KERN_ERR,
-					"error: device does not support xip");
+					"error: device does not support dax");
 			goto failed_mount;
 		}
 	}
@@ -1286,10 +1293,10 @@
 		((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
 
 	es = sbi->s_es;
-	if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT2_MOUNT_XIP) {
+	if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT2_MOUNT_DAX) {
 		ext2_msg(sb, KERN_WARNING, "warning: refusing change of "
-			 "xip flag with busy inodes while remounting");
-		sbi->s_mount_opt ^= EXT2_MOUNT_XIP;
+			 "dax flag with busy inodes while remounting");
+		sbi->s_mount_opt ^= EXT2_MOUNT_DAX;
 	}
 	if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) {
 		spin_unlock(&sbi->s_lock);