linux/fs/xfs/linux-2.6/xfs_file.c

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/*
* Copyright (c) 2000-2005 Silicon Graphics, Inc.
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it would be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "xfs.h"
#include "xfs_bit.h"
#include "xfs_log.h"
#include "xfs_inum.h"
#include "xfs_sb.h"
#include "xfs_ag.h"
#include "xfs_dir2.h"
#include "xfs_trans.h"
#include "xfs_dmapi.h"
#include "xfs_mount.h"
#include "xfs_bmap_btree.h"
#include "xfs_alloc_btree.h"
#include "xfs_ialloc_btree.h"
#include "xfs_alloc.h"
#include "xfs_btree.h"
#include "xfs_attr_sf.h"
#include "xfs_dir2_sf.h"
#include "xfs_dinode.h"
#include "xfs_inode.h"
#include "xfs_error.h"
#include "xfs_rw.h"
#include "xfs_ioctl32.h"
#include <linux/dcache.h>
#include <linux/smp_lock.h>
static struct vm_operations_struct xfs_file_vm_ops;
#ifdef CONFIG_XFS_DMAPI
static struct vm_operations_struct xfs_dmapi_file_vm_ops;
#endif
STATIC_INLINE ssize_t
__xfs_file_read(
struct kiocb *iocb,
const struct iovec *iov,
unsigned long nr_segs,
int ioflags,
loff_t pos)
{
struct file *file = iocb->ki_filp;
bhv_vnode_t *vp = vn_from_inode(file->f_path.dentry->d_inode);
BUG_ON(iocb->ki_pos != pos);
if (unlikely(file->f_flags & O_DIRECT))
ioflags |= IO_ISDIRECT;
return bhv_vop_read(vp, iocb, iov, nr_segs, &iocb->ki_pos,
ioflags, NULL);
}
STATIC ssize_t
xfs_file_aio_read(
struct kiocb *iocb,
const struct iovec *iov,
unsigned long nr_segs,
loff_t pos)
{
return __xfs_file_read(iocb, iov, nr_segs, IO_ISAIO, pos);
}
STATIC ssize_t
xfs_file_aio_read_invis(
struct kiocb *iocb,
const struct iovec *iov,
unsigned long nr_segs,
loff_t pos)
{
return __xfs_file_read(iocb, iov, nr_segs, IO_ISAIO|IO_INVIS, pos);
}
STATIC_INLINE ssize_t
__xfs_file_write(
struct kiocb *iocb,
const struct iovec *iov,
unsigned long nr_segs,
int ioflags,
loff_t pos)
{
struct file *file = iocb->ki_filp;
struct inode *inode = file->f_mapping->host;
bhv_vnode_t *vp = vn_from_inode(inode);
BUG_ON(iocb->ki_pos != pos);
if (unlikely(file->f_flags & O_DIRECT))
ioflags |= IO_ISDIRECT;
return bhv_vop_write(vp, iocb, iov, nr_segs, &iocb->ki_pos,
ioflags, NULL);
}
STATIC ssize_t
xfs_file_aio_write(
struct kiocb *iocb,
const struct iovec *iov,
unsigned long nr_segs,
loff_t pos)
{
return __xfs_file_write(iocb, iov, nr_segs, IO_ISAIO, pos);
}
STATIC ssize_t
xfs_file_aio_write_invis(
struct kiocb *iocb,
const struct iovec *iov,
unsigned long nr_segs,
loff_t pos)
{
return __xfs_file_write(iocb, iov, nr_segs, IO_ISAIO|IO_INVIS, pos);
}
STATIC ssize_t
xfs_file_splice_read(
struct file *infilp,
loff_t *ppos,
struct pipe_inode_info *pipe,
size_t len,
unsigned int flags)
{
return bhv_vop_splice_read(vn_from_inode(infilp->f_path.dentry->d_inode),
infilp, ppos, pipe, len, flags, 0, NULL);
}
STATIC ssize_t
xfs_file_splice_read_invis(
struct file *infilp,
loff_t *ppos,
struct pipe_inode_info *pipe,
size_t len,
unsigned int flags)
{
return bhv_vop_splice_read(vn_from_inode(infilp->f_path.dentry->d_inode),
infilp, ppos, pipe, len, flags, IO_INVIS,
NULL);
}
STATIC ssize_t
xfs_file_splice_write(
struct pipe_inode_info *pipe,
struct file *outfilp,
loff_t *ppos,
size_t len,
unsigned int flags)
{
return bhv_vop_splice_write(vn_from_inode(outfilp->f_path.dentry->d_inode),
pipe, outfilp, ppos, len, flags, 0, NULL);
}
STATIC ssize_t
xfs_file_splice_write_invis(
struct pipe_inode_info *pipe,
struct file *outfilp,
loff_t *ppos,
size_t len,
unsigned int flags)
{
return bhv_vop_splice_write(vn_from_inode(outfilp->f_path.dentry->d_inode),
pipe, outfilp, ppos, len, flags, IO_INVIS,
NULL);
}
STATIC int
xfs_file_open(
struct inode *inode,
struct file *filp)
{
if (!(filp->f_flags & O_LARGEFILE) && i_size_read(inode) > MAX_NON_LFS)
return -EFBIG;
return -bhv_vop_open(vn_from_inode(inode), NULL);
}
STATIC int
xfs_file_release(
struct inode *inode,
struct file *filp)
{
bhv_vnode_t *vp = vn_from_inode(inode);
if (vp)
return -bhv_vop_release(vp);
return 0;
}
STATIC int
xfs_file_fsync(
struct file *filp,
struct dentry *dentry,
int datasync)
{
bhv_vnode_t *vp = vn_from_inode(dentry->d_inode);
int flags = FSYNC_WAIT;
if (datasync)
flags |= FSYNC_DATA;
if (VN_TRUNC(vp))
VUNTRUNCATE(vp);
return -bhv_vop_fsync(vp, flags, NULL, (xfs_off_t)0, (xfs_off_t)-1);
}
#ifdef CONFIG_XFS_DMAPI
STATIC struct page *
mm: merge populate and nopage into fault (fixes nonlinear) Nonlinear mappings are (AFAIKS) simply a virtual memory concept that encodes the virtual address -> file offset differently from linear mappings. ->populate is a layering violation because the filesystem/pagecache code should need to know anything about the virtual memory mapping. The hitch here is that the ->nopage handler didn't pass down enough information (ie. pgoff). But it is more logical to pass pgoff rather than have the ->nopage function calculate it itself anyway (because that's a similar layering violation). Having the populate handler install the pte itself is likewise a nasty thing to be doing. This patch introduces a new fault handler that replaces ->nopage and ->populate and (later) ->nopfn. Most of the old mechanism is still in place so there is a lot of duplication and nice cleanups that can be removed if everyone switches over. The rationale for doing this in the first place is that nonlinear mappings are subject to the pagefault vs invalidate/truncate race too, and it seemed stupid to duplicate the synchronisation logic rather than just consolidate the two. After this patch, MAP_NONBLOCK no longer sets up ptes for pages present in pagecache. Seems like a fringe functionality anyway. NOPAGE_REFAULT is removed. This should be implemented with ->fault, and no users have hit mainline yet. [akpm@linux-foundation.org: cleanup] [randy.dunlap@oracle.com: doc. fixes for readahead] [akpm@linux-foundation.org: build fix] Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Mark Fasheh <mark.fasheh@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 08:46:59 +00:00
xfs_vm_fault(
struct vm_area_struct *vma,
struct fault_data *fdata)
{
mm: merge populate and nopage into fault (fixes nonlinear) Nonlinear mappings are (AFAIKS) simply a virtual memory concept that encodes the virtual address -> file offset differently from linear mappings. ->populate is a layering violation because the filesystem/pagecache code should need to know anything about the virtual memory mapping. The hitch here is that the ->nopage handler didn't pass down enough information (ie. pgoff). But it is more logical to pass pgoff rather than have the ->nopage function calculate it itself anyway (because that's a similar layering violation). Having the populate handler install the pte itself is likewise a nasty thing to be doing. This patch introduces a new fault handler that replaces ->nopage and ->populate and (later) ->nopfn. Most of the old mechanism is still in place so there is a lot of duplication and nice cleanups that can be removed if everyone switches over. The rationale for doing this in the first place is that nonlinear mappings are subject to the pagefault vs invalidate/truncate race too, and it seemed stupid to duplicate the synchronisation logic rather than just consolidate the two. After this patch, MAP_NONBLOCK no longer sets up ptes for pages present in pagecache. Seems like a fringe functionality anyway. NOPAGE_REFAULT is removed. This should be implemented with ->fault, and no users have hit mainline yet. [akpm@linux-foundation.org: cleanup] [randy.dunlap@oracle.com: doc. fixes for readahead] [akpm@linux-foundation.org: build fix] Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Mark Fasheh <mark.fasheh@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 08:46:59 +00:00
struct inode *inode = vma->vm_file->f_path.dentry->d_inode;
bhv_vnode_t *vp = vn_from_inode(inode);
ASSERT_ALWAYS(vp->v_vfsp->vfs_flag & VFS_DMI);
mm: merge populate and nopage into fault (fixes nonlinear) Nonlinear mappings are (AFAIKS) simply a virtual memory concept that encodes the virtual address -> file offset differently from linear mappings. ->populate is a layering violation because the filesystem/pagecache code should need to know anything about the virtual memory mapping. The hitch here is that the ->nopage handler didn't pass down enough information (ie. pgoff). But it is more logical to pass pgoff rather than have the ->nopage function calculate it itself anyway (because that's a similar layering violation). Having the populate handler install the pte itself is likewise a nasty thing to be doing. This patch introduces a new fault handler that replaces ->nopage and ->populate and (later) ->nopfn. Most of the old mechanism is still in place so there is a lot of duplication and nice cleanups that can be removed if everyone switches over. The rationale for doing this in the first place is that nonlinear mappings are subject to the pagefault vs invalidate/truncate race too, and it seemed stupid to duplicate the synchronisation logic rather than just consolidate the two. After this patch, MAP_NONBLOCK no longer sets up ptes for pages present in pagecache. Seems like a fringe functionality anyway. NOPAGE_REFAULT is removed. This should be implemented with ->fault, and no users have hit mainline yet. [akpm@linux-foundation.org: cleanup] [randy.dunlap@oracle.com: doc. fixes for readahead] [akpm@linux-foundation.org: build fix] Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Mark Fasheh <mark.fasheh@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 08:46:59 +00:00
if (XFS_SEND_MMAP(XFS_VFSTOM(vp->v_vfsp), vma, 0)) {
fdata->type = VM_FAULT_SIGBUS;
return NULL;
mm: merge populate and nopage into fault (fixes nonlinear) Nonlinear mappings are (AFAIKS) simply a virtual memory concept that encodes the virtual address -> file offset differently from linear mappings. ->populate is a layering violation because the filesystem/pagecache code should need to know anything about the virtual memory mapping. The hitch here is that the ->nopage handler didn't pass down enough information (ie. pgoff). But it is more logical to pass pgoff rather than have the ->nopage function calculate it itself anyway (because that's a similar layering violation). Having the populate handler install the pte itself is likewise a nasty thing to be doing. This patch introduces a new fault handler that replaces ->nopage and ->populate and (later) ->nopfn. Most of the old mechanism is still in place so there is a lot of duplication and nice cleanups that can be removed if everyone switches over. The rationale for doing this in the first place is that nonlinear mappings are subject to the pagefault vs invalidate/truncate race too, and it seemed stupid to duplicate the synchronisation logic rather than just consolidate the two. After this patch, MAP_NONBLOCK no longer sets up ptes for pages present in pagecache. Seems like a fringe functionality anyway. NOPAGE_REFAULT is removed. This should be implemented with ->fault, and no users have hit mainline yet. [akpm@linux-foundation.org: cleanup] [randy.dunlap@oracle.com: doc. fixes for readahead] [akpm@linux-foundation.org: build fix] Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Mark Fasheh <mark.fasheh@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 08:46:59 +00:00
}
return filemap_fault(vma, fdata);
}
#endif /* CONFIG_XFS_DMAPI */
STATIC int
xfs_file_readdir(
struct file *filp,
void *dirent,
filldir_t filldir)
{
int error = 0;
bhv_vnode_t *vp = vn_from_inode(filp->f_path.dentry->d_inode);
uio_t uio;
iovec_t iov;
int eof = 0;
caddr_t read_buf;
int namelen, size = 0;
size_t rlen = PAGE_CACHE_SIZE;
xfs_off_t start_offset, curr_offset;
xfs_dirent_t *dbp = NULL;
/* Try fairly hard to get memory */
do {
if ((read_buf = kmalloc(rlen, GFP_KERNEL)))
break;
rlen >>= 1;
} while (rlen >= 1024);
if (read_buf == NULL)
return -ENOMEM;
uio.uio_iov = &iov;
uio.uio_segflg = UIO_SYSSPACE;
curr_offset = filp->f_pos;
if (filp->f_pos != 0x7fffffff)
uio.uio_offset = filp->f_pos;
else
uio.uio_offset = 0xffffffff;
while (!eof) {
uio.uio_resid = iov.iov_len = rlen;
iov.iov_base = read_buf;
uio.uio_iovcnt = 1;
start_offset = uio.uio_offset;
error = bhv_vop_readdir(vp, &uio, NULL, &eof);
if ((uio.uio_offset == start_offset) || error) {
size = 0;
break;
}
size = rlen - uio.uio_resid;
dbp = (xfs_dirent_t *)read_buf;
while (size > 0) {
namelen = strlen(dbp->d_name);
if (filldir(dirent, dbp->d_name, namelen,
(loff_t) curr_offset & 0x7fffffff,
(ino_t) dbp->d_ino,
DT_UNKNOWN)) {
goto done;
}
size -= dbp->d_reclen;
curr_offset = (loff_t)dbp->d_off /* & 0x7fffffff */;
dbp = (xfs_dirent_t *)((char *)dbp + dbp->d_reclen);
}
}
done:
if (!error) {
if (size == 0)
filp->f_pos = uio.uio_offset & 0x7fffffff;
else if (dbp)
filp->f_pos = curr_offset;
}
kfree(read_buf);
return -error;
}
STATIC int
xfs_file_mmap(
struct file *filp,
struct vm_area_struct *vma)
{
vma->vm_ops = &xfs_file_vm_ops;
mm: merge populate and nopage into fault (fixes nonlinear) Nonlinear mappings are (AFAIKS) simply a virtual memory concept that encodes the virtual address -> file offset differently from linear mappings. ->populate is a layering violation because the filesystem/pagecache code should need to know anything about the virtual memory mapping. The hitch here is that the ->nopage handler didn't pass down enough information (ie. pgoff). But it is more logical to pass pgoff rather than have the ->nopage function calculate it itself anyway (because that's a similar layering violation). Having the populate handler install the pte itself is likewise a nasty thing to be doing. This patch introduces a new fault handler that replaces ->nopage and ->populate and (later) ->nopfn. Most of the old mechanism is still in place so there is a lot of duplication and nice cleanups that can be removed if everyone switches over. The rationale for doing this in the first place is that nonlinear mappings are subject to the pagefault vs invalidate/truncate race too, and it seemed stupid to duplicate the synchronisation logic rather than just consolidate the two. After this patch, MAP_NONBLOCK no longer sets up ptes for pages present in pagecache. Seems like a fringe functionality anyway. NOPAGE_REFAULT is removed. This should be implemented with ->fault, and no users have hit mainline yet. [akpm@linux-foundation.org: cleanup] [randy.dunlap@oracle.com: doc. fixes for readahead] [akpm@linux-foundation.org: build fix] Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Mark Fasheh <mark.fasheh@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 08:46:59 +00:00
vma->vm_flags |= VM_CAN_INVALIDATE | VM_CAN_NONLINEAR;
#ifdef CONFIG_XFS_DMAPI
if (vn_from_inode(filp->f_path.dentry->d_inode)->v_vfsp->vfs_flag & VFS_DMI)
vma->vm_ops = &xfs_dmapi_file_vm_ops;
#endif /* CONFIG_XFS_DMAPI */
file_accessed(filp);
return 0;
}
STATIC long
xfs_file_ioctl(
struct file *filp,
unsigned int cmd,
unsigned long p)
{
int error;
struct inode *inode = filp->f_path.dentry->d_inode;
bhv_vnode_t *vp = vn_from_inode(inode);
error = bhv_vop_ioctl(vp, inode, filp, 0, cmd, (void __user *)p);
VMODIFY(vp);
/* NOTE: some of the ioctl's return positive #'s as a
* byte count indicating success, such as
* readlink_by_handle. So we don't "sign flip"
* like most other routines. This means true
* errors need to be returned as a negative value.
*/
return error;
}
STATIC long
xfs_file_ioctl_invis(
struct file *filp,
unsigned int cmd,
unsigned long p)
{
int error;
struct inode *inode = filp->f_path.dentry->d_inode;
bhv_vnode_t *vp = vn_from_inode(inode);
error = bhv_vop_ioctl(vp, inode, filp, IO_INVIS, cmd, (void __user *)p);
VMODIFY(vp);
/* NOTE: some of the ioctl's return positive #'s as a
* byte count indicating success, such as
* readlink_by_handle. So we don't "sign flip"
* like most other routines. This means true
* errors need to be returned as a negative value.
*/
return error;
}
#ifdef CONFIG_XFS_DMAPI
#ifdef HAVE_VMOP_MPROTECT
STATIC int
xfs_vm_mprotect(
struct vm_area_struct *vma,
unsigned int newflags)
{
bhv_vnode_t *vp = vn_from_inode(vma->vm_file->f_path.dentry->d_inode);
int error = 0;
if (vp->v_vfsp->vfs_flag & VFS_DMI) {
if ((vma->vm_flags & VM_MAYSHARE) &&
(newflags & VM_WRITE) && !(vma->vm_flags & VM_WRITE)) {
xfs_mount_t *mp = XFS_VFSTOM(vp->v_vfsp);
error = XFS_SEND_MMAP(mp, vma, VM_WRITE);
}
}
return error;
}
#endif /* HAVE_VMOP_MPROTECT */
#endif /* CONFIG_XFS_DMAPI */
#ifdef HAVE_FOP_OPEN_EXEC
/* If the user is attempting to execute a file that is offline then
* we have to trigger a DMAPI READ event before the file is marked as busy
* otherwise the invisible I/O will not be able to write to the file to bring
* it back online.
*/
STATIC int
xfs_file_open_exec(
struct inode *inode)
{
bhv_vnode_t *vp = vn_from_inode(inode);
if (unlikely(vp->v_vfsp->vfs_flag & VFS_DMI)) {
xfs_mount_t *mp = XFS_VFSTOM(vp->v_vfsp);
xfs_inode_t *ip = xfs_vtoi(vp);
if (!ip)
return -EINVAL;
if (DM_EVENT_ENABLED(vp->v_vfsp, ip, DM_EVENT_READ))
return -XFS_SEND_DATA(mp, DM_EVENT_READ, vp,
0, 0, 0, NULL);
}
return 0;
}
#endif /* HAVE_FOP_OPEN_EXEC */
const struct file_operations xfs_file_operations = {
.llseek = generic_file_llseek,
.read = do_sync_read,
.write = do_sync_write,
.aio_read = xfs_file_aio_read,
.aio_write = xfs_file_aio_write,
.splice_read = xfs_file_splice_read,
.splice_write = xfs_file_splice_write,
.unlocked_ioctl = xfs_file_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = xfs_file_compat_ioctl,
#endif
.mmap = xfs_file_mmap,
.open = xfs_file_open,
.release = xfs_file_release,
.fsync = xfs_file_fsync,
#ifdef HAVE_FOP_OPEN_EXEC
.open_exec = xfs_file_open_exec,
#endif
};
const struct file_operations xfs_invis_file_operations = {
.llseek = generic_file_llseek,
.read = do_sync_read,
.write = do_sync_write,
.aio_read = xfs_file_aio_read_invis,
.aio_write = xfs_file_aio_write_invis,
.splice_read = xfs_file_splice_read_invis,
.splice_write = xfs_file_splice_write_invis,
.unlocked_ioctl = xfs_file_ioctl_invis,
#ifdef CONFIG_COMPAT
.compat_ioctl = xfs_file_compat_invis_ioctl,
#endif
.mmap = xfs_file_mmap,
.open = xfs_file_open,
.release = xfs_file_release,
.fsync = xfs_file_fsync,
};
const struct file_operations xfs_dir_file_operations = {
.read = generic_read_dir,
.readdir = xfs_file_readdir,
.unlocked_ioctl = xfs_file_ioctl,
#ifdef CONFIG_COMPAT
.compat_ioctl = xfs_file_compat_ioctl,
#endif
.fsync = xfs_file_fsync,
};
static struct vm_operations_struct xfs_file_vm_ops = {
mm: merge populate and nopage into fault (fixes nonlinear) Nonlinear mappings are (AFAIKS) simply a virtual memory concept that encodes the virtual address -> file offset differently from linear mappings. ->populate is a layering violation because the filesystem/pagecache code should need to know anything about the virtual memory mapping. The hitch here is that the ->nopage handler didn't pass down enough information (ie. pgoff). But it is more logical to pass pgoff rather than have the ->nopage function calculate it itself anyway (because that's a similar layering violation). Having the populate handler install the pte itself is likewise a nasty thing to be doing. This patch introduces a new fault handler that replaces ->nopage and ->populate and (later) ->nopfn. Most of the old mechanism is still in place so there is a lot of duplication and nice cleanups that can be removed if everyone switches over. The rationale for doing this in the first place is that nonlinear mappings are subject to the pagefault vs invalidate/truncate race too, and it seemed stupid to duplicate the synchronisation logic rather than just consolidate the two. After this patch, MAP_NONBLOCK no longer sets up ptes for pages present in pagecache. Seems like a fringe functionality anyway. NOPAGE_REFAULT is removed. This should be implemented with ->fault, and no users have hit mainline yet. [akpm@linux-foundation.org: cleanup] [randy.dunlap@oracle.com: doc. fixes for readahead] [akpm@linux-foundation.org: build fix] Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Mark Fasheh <mark.fasheh@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 08:46:59 +00:00
.fault = filemap_fault,
};
#ifdef CONFIG_XFS_DMAPI
static struct vm_operations_struct xfs_dmapi_file_vm_ops = {
mm: merge populate and nopage into fault (fixes nonlinear) Nonlinear mappings are (AFAIKS) simply a virtual memory concept that encodes the virtual address -> file offset differently from linear mappings. ->populate is a layering violation because the filesystem/pagecache code should need to know anything about the virtual memory mapping. The hitch here is that the ->nopage handler didn't pass down enough information (ie. pgoff). But it is more logical to pass pgoff rather than have the ->nopage function calculate it itself anyway (because that's a similar layering violation). Having the populate handler install the pte itself is likewise a nasty thing to be doing. This patch introduces a new fault handler that replaces ->nopage and ->populate and (later) ->nopfn. Most of the old mechanism is still in place so there is a lot of duplication and nice cleanups that can be removed if everyone switches over. The rationale for doing this in the first place is that nonlinear mappings are subject to the pagefault vs invalidate/truncate race too, and it seemed stupid to duplicate the synchronisation logic rather than just consolidate the two. After this patch, MAP_NONBLOCK no longer sets up ptes for pages present in pagecache. Seems like a fringe functionality anyway. NOPAGE_REFAULT is removed. This should be implemented with ->fault, and no users have hit mainline yet. [akpm@linux-foundation.org: cleanup] [randy.dunlap@oracle.com: doc. fixes for readahead] [akpm@linux-foundation.org: build fix] Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: Mark Fasheh <mark.fasheh@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 08:46:59 +00:00
.fault = xfs_vm_fault,
#ifdef HAVE_VMOP_MPROTECT
.mprotect = xfs_vm_mprotect,
#endif
};
#endif /* CONFIG_XFS_DMAPI */