vfs: remove get_xip_mem

All callers of get_xip_mem() are now gone.  Remove checks for it,
initialisers of it, documentation of it and the only implementation of it.
 Also remove mm/filemap_xip.c as it is now empty.  Also remove
documentation of the long-gone get_xip_page().

Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.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: Mathieu Desnoyers <mathieu.desnoyers@efficios.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>

13 files changed, 7 insertions, 95 deletions

diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking
index b30753cbf431..2ca3d17eee56 100644
--- a/Documentation/filesystems/Locking
+++ b/Documentation/filesystems/Locking
@@ -199,8 +199,6 @@ prototypes:
         int (*releasepage) (struct page *, int);
         void (*freepage)(struct page *);
         int (*direct_IO)(int, struct kiocb *, struct iov_iter *iter, loff_t offset);
-        int (*get_xip_mem)(struct address_space *, pgoff_t, int, void **,
-                                unsigned long *);
         int (*migratepage)(struct address_space *, struct page *, struct page *);
         int (*launder_page)(struct page *);
         int (*is_partially_uptodate)(struct page *, unsigned long, unsigned long);
@@ -225,7 +223,6 @@ invalidatepage:		yes
 releasepage:            yes
 freepage:               yes
 direct_IO:
-get_xip_mem:                                    maybe
 migratepage:            yes (both)
 launder_page:           yes
 is_partially_uptodate:  yes
diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
index 43ce0507ee25..966b22829f3b 100644
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.txt
@@ -591,8 +591,6 @@ struct address_space_operations {
         int (*releasepage) (struct page *, int);
         void (*freepage)(struct page *);
         ssize_t (*direct_IO)(int, struct kiocb *, struct iov_iter *iter, loff_t offset);
-        struct page* (*get_xip_page)(struct address_space *, sector_t,
-                        int);
         /* migrate the contents of a page to the specified target */
         int (*migratepage) (struct page *, struct page *);
         int (*launder_page) (struct page *);
@@ -748,11 +746,6 @@ struct address_space_operations {
         and transfer data directly between the storage and the
         application's address space.
 
-  get_xip_page: called by the VM to translate a block number to a page.
-        The page is valid until the corresponding filesystem is unmounted.
-        Filesystems that want to use execute-in-place (XIP) need to implement
-        it.  An example implementation can be found in fs/ext2/xip.c.
-
   migrate_page:  This is used to compact the physical memory usage.
         If the VM wants to relocate a page (maybe off a memory card
         that is signalling imminent failure) it will pass a new page
diff --git a/fs/exofs/inode.c b/fs/exofs/inode.c
index 6fc91df99ff8..a198e94813fe 100644
--- a/fs/exofs/inode.c
+++ b/fs/exofs/inode.c
@@ -985,7 +985,6 @@ const struct address_space_operations exofs_aops = {
         .direct_IO      = exofs_direct_IO,
 
         /* With these NULL has special meaning or default is not exported */
-        .get_xip_mem    = NULL,
         .migratepage    = NULL,
         .launder_page   = NULL,
         .is_partially_uptodate = NULL,
diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c
index 5ac0a3461b3c..59d6c7d43740 100644
--- a/fs/ext2/inode.c
+++ b/fs/ext2/inode.c
@@ -894,7 +894,6 @@ const struct address_space_operations ext2_aops = {
 
 const struct address_space_operations ext2_aops_xip = {
         .bmap                   = ext2_bmap,
-        .get_xip_mem            = ext2_get_xip_mem,
         .direct_IO              = ext2_direct_IO,
 };
 
diff --git a/fs/ext2/xip.c b/fs/ext2/xip.c
index 8cfca3a4cd58..132d4daf98c4 100644
--- a/fs/ext2/xip.c
+++ b/fs/ext2/xip.c
@@ -13,35 +13,6 @@
 #include "ext2.h"
 #include "xip.h"
 
-static inline long __inode_direct_access(struct inode *inode, sector_t block,
-                                void **kaddr, unsigned long *pfn, long size)
-{
-        struct block_device *bdev = inode->i_sb->s_bdev;
-        sector_t sector = block * (PAGE_SIZE / 512);
-        return bdev_direct_access(bdev, sector, kaddr, pfn, size);
-}
-
-static inline int
-__ext2_get_block(struct inode *inode, pgoff_t pgoff, int create,
-                   sector_t *result)
-{
-        struct buffer_head tmp;
-        int rc;
-
-        memset(&tmp, 0, sizeof(struct buffer_head));
-        tmp.b_size = 1 << inode->i_blkbits;
-        rc = ext2_get_block(inode, pgoff, &tmp, create);
-        *result = tmp.b_blocknr;
-
-        /* did we get a sparse block (hole in the file)? */
-        if (!tmp.b_blocknr && !rc) {
-                BUG_ON(create);
-                rc = -ENODATA;
-        }
-
-        return rc;
-}
-
 void ext2_xip_verify_sb(struct super_block *sb)
 {
         struct ext2_sb_info *sbi = EXT2_SB(sb);
@@ -54,19 +25,3 @@ void ext2_xip_verify_sb(struct super_block *sb)
                              "not supported by bdev");
         }
 }
-
-int ext2_get_xip_mem(struct address_space *mapping, pgoff_t pgoff, int create,
-                                void **kmem, unsigned long *pfn)
-{
-        long rc;
-        sector_t block;
-
-        /* first, retrieve the sector number */
-        rc = __ext2_get_block(mapping->host, pgoff, create, &block);
-        if (rc)
-                return rc;
-
-        /* retrieve address of the target data */
-        rc = __inode_direct_access(mapping->host, block, kmem, pfn, PAGE_SIZE);
-        return (rc < 0) ? rc : 0;
-}
diff --git a/fs/ext2/xip.h b/fs/ext2/xip.h
index b2592f2f3c9d..e7b9f0a2cc54 100644
--- a/fs/ext2/xip.h
+++ b/fs/ext2/xip.h
@@ -12,10 +12,7 @@ static inline int ext2_use_xip (struct super_block *sb)
         struct ext2_sb_info *sbi = EXT2_SB(sb);
         return (sbi->s_mount_opt & EXT2_MOUNT_XIP);
 }
-int ext2_get_xip_mem(struct address_space *, pgoff_t, int,
-                                void **, unsigned long *);
 #else
 #define ext2_xip_verify_sb(sb)                  do { } while (0)
 #define ext2_use_xip(sb)                        0
-#define ext2_get_xip_mem                        NULL
 #endif
diff --git a/fs/open.c b/fs/open.c
index 813be037b412..a293c2020676 100644
--- a/fs/open.c
+++ b/fs/open.c
@@ -667,11 +667,8 @@ int open_check_o_direct(struct file *f)
 {
         /* NB: we're sure to have correct a_ops only after f_op->open */
         if (f->f_flags & O_DIRECT) {
-                if (!f->f_mapping->a_ops ||
-                    ((!f->f_mapping->a_ops->direct_IO) &&
-                    (!f->f_mapping->a_ops->get_xip_mem))) {
+                if (!f->f_mapping->a_ops || !f->f_mapping->a_ops->direct_IO)
                         return -EINVAL;
-                }
         }
         return 0;
 }
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 2c8f9055af38..9772d655f444 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -362,8 +362,6 @@ struct address_space_operations {
         int (*releasepage) (struct page *, gfp_t);
         void (*freepage)(struct page *);
         ssize_t (*direct_IO)(int, struct kiocb *, struct iov_iter *iter, loff_t offset);
-        int (*get_xip_mem)(struct address_space *, pgoff_t, int,
-                                                void **, unsigned long *);
         /*
          * migrate the contents of a page to the specified target. If
          * migrate_mode is MIGRATE_ASYNC, it must not block.
diff --git a/include/linux/rmap.h b/include/linux/rmap.h
index b38f559130d5..c4c559a45dc8 100644
--- a/include/linux/rmap.h
+++ b/include/linux/rmap.h
@@ -198,7 +198,7 @@ int page_referenced(struct page *, int is_locked,
 int try_to_unmap(struct page *, enum ttu_flags flags);
 
 /*
- * Called from mm/filemap_xip.c to unmap empty zero page
+ * Used by uprobes to replace a userspace page safely
  */
 pte_t *__page_check_address(struct page *, struct mm_struct *,
                                 unsigned long, spinlock_t **, int);
diff --git a/mm/Makefile b/mm/Makefile
index 088c68e9ec35..3c1caa2693bd 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -55,7 +55,6 @@ obj-$(CONFIG_KMEMCHECK) += kmemcheck.o
 obj-$(CONFIG_KASAN)     += kasan/
 obj-$(CONFIG_FAILSLAB) += failslab.o
 obj-$(CONFIG_MEMORY_HOTPLUG) += memory_hotplug.o
-obj-$(CONFIG_FS_XIP) += filemap_xip.o
 obj-$(CONFIG_MIGRATION) += migrate.o
 obj-$(CONFIG_QUICKLIST) += quicklist.o
 obj-$(CONFIG_TRANSPARENT_HUGEPAGE) += huge_memory.o
diff --git a/mm/fadvise.c b/mm/fadvise.c
index fac23ecf8d72..4a3907cf79f8 100644
--- a/mm/fadvise.c
+++ b/mm/fadvise.c
@@ -28,6 +28,7 @@
 SYSCALL_DEFINE4(fadvise64_64, int, fd, loff_t, offset, loff_t, len, int, advice)
 {
         struct fd f = fdget(fd);
+        struct inode *inode;
         struct address_space *mapping;
         struct backing_dev_info *bdi;
         loff_t endbyte;                 /* inclusive */
@@ -39,7 +40,8 @@ SYSCALL_DEFINE4(fadvise64_64, int, fd, loff_t, offset, loff_t, len, int, advice)
         if (!f.file)
                 return -EBADF;
 
-        if (S_ISFIFO(file_inode(f.file)->i_mode)) {
+        inode = file_inode(f.file);
+        if (S_ISFIFO(inode->i_mode)) {
                 ret = -ESPIPE;
                 goto out;
         }
@@ -50,7 +52,7 @@ SYSCALL_DEFINE4(fadvise64_64, int, fd, loff_t, offset, loff_t, len, int, advice)
                 goto out;
         }
 
-        if (mapping->a_ops->get_xip_mem) {
+        if (IS_DAX(inode)) {
                 switch (advice) {
                 case POSIX_FADV_NORMAL:
                 case POSIX_FADV_RANDOM:
diff --git a/mm/filemap_xip.c b/mm/filemap_xip.c
deleted file mode 100644
index 8e3f99b61959..000000000000
--- a/mm/filemap_xip.c
+++ /dev/null
@@ -1,24 +0,0 @@
-/*
- *      linux/mm/filemap_xip.c
- *
- * Copyright (C) 2005 IBM Corporation
- * Author: Carsten Otte <cotte@de.ibm.com>
- *
- * derived from linux/mm/filemap.c - Copyright (C) Linus Torvalds
- *
- */
-
-#include <linux/fs.h>
-#include <linux/backing-dev.h>
-#include <linux/pagemap.h>
-#include <linux/export.h>
-#include <linux/uio.h>
-#include <linux/rmap.h>
-#include <linux/mmu_notifier.h>
-#include <linux/sched.h>
-#include <linux/seqlock.h>
-#include <linux/mutex.h>
-#include <linux/gfp.h>
-#include <asm/tlbflush.h>
-#include <asm/io.h>
-
diff --git a/mm/madvise.c b/mm/madvise.c
index 1077cbdc8b52..d551475517bf 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -239,7 +239,7 @@ static long madvise_willneed(struct vm_area_struct *vma,
                 return -EBADF;
 #endif
 
-        if (file->f_mapping->a_ops->get_xip_mem) {
+        if (IS_DAX(file_inode(file))) {
                 /* no bad return value, but ignore advice */
                 return 0;
         }