[01/36] Pagecache zeroing: zero_user_segment, zero_user_segments and zero_user

clameter
2007-08-28T19:26:35Z

[-- Attachment #1: 0001-Pagecache-zeroing-zero_user_segment-zero_user_segm.patch --]
[-- Type: text/plain, Size: 28592 bytes --]

Simplify page cache zeroing of segments of pages through 3 functions

zero_user_segments(page, start1, end1, start2, end2)

Zeros two segments of the page. It takes the position where to
start and end the zeroing which avoids length calculations.

zero_user_segment(page, start, end)

Same for a single segment.

zero_user(page, start, length)

Length variant for the case where we know the length.

We remove the zero_user_page macro. Issues:

1. Its a macro. Inline functions are preferable.

2. The KM_USER0 macro is only defined for HIGHMEM.

Having to treat this special case everywhere makes the
code needlessly complex. The parameter for zeroing is always
KM_USER0 except in one single case that we open code.

Avoiding KM_USER0 makes a lot of code not having to be dealing
with the special casing for HIGHMEM anymore. Dealing with
kmap is only necessary for HIGHMEM configurations. In those
configurations we use KM_USER0 like we do for a series of other
functions defined in highmem.h.

Since KM_USER0 is depends on HIGHMEM the existing zero_user_page
function could not be a macro. zero_user_* functions introduced
here can be be inline because that constant is not used when these
functions are called.

Also extract the flushing of the caches to be outside of the kmap.

Signed-off-by: Christoph Lameter <clameter@sgi.com>
---
drivers/block/loop.c | 2 +-
fs/buffer.c | 48 +++++++++++++-----------------------------
fs/cifs/inode.c | 2 +-
fs/direct-io.c | 4 +-
fs/ecryptfs/mmap.c | 7 ++---
fs/ext3/inode.c | 4 +-
fs/ext4/inode.c | 4 +-
fs/gfs2/bmap.c | 2 +-
fs/gfs2/ops_address.c | 2 +-
fs/libfs.c | 11 +++------
fs/mpage.c | 7 +----
fs/nfs/read.c | 10 ++++----
fs/nfs/write.c | 2 +-
fs/ntfs/aops.c | 18 +++++++++-------
fs/ntfs/file.c | 32 +++++++++++++---------------
fs/ocfs2/aops.c | 6 ++--
fs/reiserfs/inode.c | 4 +-
fs/xfs/linux-2.6/xfs_lrw.c | 2 +-
include/linux/highmem.h | 49 +++++++++++++++++++++++++++----------------
mm/filemap_xip.c | 2 +-
mm/truncate.c | 2 +-
21 files changed, 104 insertions(+), 116 deletions(-)

Index: linux-2.6/drivers/block/loop.c
===================================================================
--- linux-2.6.orig/drivers/block/loop.c 2007-08-27 19:22:13.000000000 -0700
+++ linux-2.6/drivers/block/loop.c 2007-08-27 19:22:17.000000000 -0700
@@ -251,7 +251,7 @@ static int do_lo_send_aops(struct loop_d
*/
printk(KERN_ERR "loop: transfer error block %llu\n",
(unsigned long long)index);
- zero_user_page(page, offset, size, KM_USER0);
+ zero_user(page, offset, size);
}
flush_dcache_page(page);
ret = aops->commit_write(file, page, offset,
Index: linux-2.6/fs/buffer.c
===================================================================
--- linux-2.6.orig/fs/buffer.c 2007-08-27 19:22:13.000000000 -0700
+++ linux-2.6/fs/buffer.c 2007-08-27 19:22:17.000000000 -0700
@@ -1803,19 +1803,10 @@ static int __block_prepare_write(struct
set_buffer_uptodate(bh);
continue;
}
- if (block_end > to || block_start < from) {
- void *kaddr;
-
- kaddr = kmap_atomic(page, KM_USER0);
- if (block_end > to)
- memset(kaddr+to, 0,
- block_end-to);
- if (block_start < from)
- memset(kaddr+block_start,
- 0, from-block_start);
- flush_dcache_page(page);
- kunmap_atomic(kaddr, KM_USER0);
- }
+ if (block_end > to || block_start < from)
+ zero_user_segments(page,
+ to, block_end,
+ block_start, from)
continue;
}
}
@@ -1863,7 +1854,7 @@ static int __block_prepare_write(struct
break;
if (buffer_new(bh)) {
clear_buffer_new(bh);
- zero_user_page(page, block_start, bh->b_size, KM_USER0);
+ zero_user(page, block_start, bh->b_size);
set_buffer_uptodate(bh);
mark_buffer_dirty(bh);
}
@@ -1951,8 +1942,7 @@ int block_read_full_page(struct page *pa
SetPageError(page);
}
if (!buffer_mapped(bh)) {
- zero_user_page(page, i * blocksize, blocksize,
- KM_USER0);
+ zero_user(page, i * blocksize, blocksize);
if (!err)
set_buffer_uptodate(bh);
continue;
@@ -2116,8 +2106,7 @@ int cont_prepare_write(struct page *page
PAGE_CACHE_SIZE, get_block);
if (status)
goto out_unmap;
- zero_user_page(new_page, zerofrom, PAGE_CACHE_SIZE - zerofrom,
- KM_USER0);
+ zero_user_segment(new_page, zerofrom, PAGE_CACHE_SIZE);
generic_commit_write(NULL, new_page, zerofrom, PAGE_CACHE_SIZE);
unlock_page(new_page);
page_cache_release(new_page);
@@ -2144,7 +2133,7 @@ int cont_prepare_write(struct page *page
if (status)
goto out1;
if (zerofrom < offset) {
- zero_user_page(page, zerofrom, offset - zerofrom, KM_USER0);
+ zero_user_segment(page, zerofrom, offset);
__block_commit_write(inode, page, zerofrom, offset);
}
return 0;
@@ -2277,7 +2266,6 @@ int nobh_prepare_write(struct page *page
unsigned block_in_page;
unsigned block_start;
sector_t block_in_file;
- char *kaddr;
int nr_reads = 0;
int i;
int ret = 0;
@@ -2317,13 +2305,8 @@ int nobh_prepare_write(struct page *page
if (PageUptodate(page))
continue;
if (buffer_new(&map_bh) || !buffer_mapped(&map_bh)) {
- kaddr = kmap_atomic(page, KM_USER0);
- if (block_start < from)
- memset(kaddr+block_start, 0, from-block_start);
- if (block_end > to)
- memset(kaddr + to, 0, block_end - to);
- flush_dcache_page(page);
- kunmap_atomic(kaddr, KM_USER0);
+ zero_user_segments(page, block_start, from,
+ to, block_end);
continue;
}
if (buffer_uptodate(&map_bh))
@@ -2389,7 +2372,7 @@ failed:
* Error recovery is pretty slack. Clear the page and mark it dirty
* so we'll later zero out any blocks which _were_ allocated.
*/
- zero_user_page(page, 0, PAGE_CACHE_SIZE, KM_USER0);
+ zero_user(page, 0, PAGE_CACHE_SIZE);
SetPageUptodate(page);
set_page_dirty(page);
return ret;
@@ -2458,7 +2441,7 @@ int nobh_writepage(struct page *page, ge
* the page size, the remaining memory is zeroed when mapped, and
* writes to that region are not written out to the file."
*/
- zero_user_page(page, offset, PAGE_CACHE_SIZE - offset, KM_USER0);
+ zero_user_segment(page, offset, PAGE_CACHE_SIZE);
out:
ret = mpage_writepage(page, get_block, wbc);
if (ret == -EAGAIN)
@@ -2492,8 +2475,7 @@ int nobh_truncate_page(struct address_sp
to = (offset + blocksize) & ~(blocksize - 1);
ret = a_ops->prepare_write(NULL, page, offset, to);
if (ret == 0) {
- zero_user_page(page, offset, PAGE_CACHE_SIZE - offset,
- KM_USER0);
+ zero_user_segment(page, offset, PAGE_CACHE_SIZE);
/*
* It would be more correct to call aops->commit_write()
* here, but this is more efficient.
@@ -2572,7 +2554,7 @@ int block_truncate_page(struct address_s
goto unlock;
}

- zero_user_page(page, offset, length, KM_USER0);
+ zero_user(page, offset, length);
mark_buffer_dirty(bh);
err = 0;

@@ -2618,7 +2600,7 @@ int block_write_full_page(struct page *p
* the page size, the remaining memory is zeroed when mapped, and
* writes to that region are not written out to the file."
*/
- zero_user_page(page, offset, PAGE_CACHE_SIZE - offset, KM_USER0);
+ zero_user_segment(page, offset, PAGE_CACHE_SIZE);
return __block_write_full_page(inode, page, get_block, wbc);
}

Index: linux-2.6/fs/cifs/inode.c
===================================================================
--- linux-2.6.orig/fs/cifs/inode.c 2007-08-27 19:22:13.000000000 -0700
+++ linux-2.6/fs/cifs/inode.c 2007-08-27 19:22:17.000000000 -0700
@@ -1353,7 +1353,7 @@ static int cifs_truncate_page(struct add
if (!page)
return -ENOMEM;

- zero_user_page(page, offset, PAGE_CACHE_SIZE - offset, KM_USER0);
+ zero_user_segment(page, offset, PAGE_CACHE_SIZE);
unlock_page(page);
page_cache_release(page);
return rc;
Index: linux-2.6/fs/direct-io.c
===================================================================
--- linux-2.6.orig/fs/direct-io.c 2007-08-27 19:22:13.000000000 -0700
+++ linux-2.6/fs/direct-io.c 2007-08-27 19:22:17.000000000 -0700
@@ -887,8 +887,8 @@ do_holes:
page_cache_release(page);
goto out;
}
- zero_user_page(page, block_in_page << blkbits,
- 1 << blkbits, KM_USER0);
+ zero_user(page, block_in_page << blkbits,
+ 1 << blkbits);
dio->block_in_file++;
block_in_page++;
goto next_block;
Index: linux-2.6/fs/ecryptfs/mmap.c
===================================================================
--- linux-2.6.orig/fs/ecryptfs/mmap.c 2007-08-27 19:22:13.000000000 -0700
+++ linux-2.6/fs/ecryptfs/mmap.c 2007-08-27 19:22:17.000000000 -0700
@@ -371,8 +371,7 @@ static int fill_zeros_to_end_of_page(str
end_byte_in_page = i_size_read(inode) % PAGE_CACHE_SIZE;
if (to > end_byte_in_page)
end_byte_in_page = to;
- zero_user_page(page, end_byte_in_page,
- PAGE_CACHE_SIZE - end_byte_in_page, KM_USER0);
+ zero_user_segment(page, end_byte_in_page, PAGE_CACHE_SIZE);
out:
return 0;
}
@@ -422,7 +421,7 @@ static int ecryptfs_prepare_write(struct
}
}
if (end_of_prev_pg_pos + 1 > i_size_read(page->mapping->host))
- zero_user_page(page, 0, PAGE_CACHE_SIZE, KM_USER0);
+ zero_user(page, 0, PAGE_CACHE_SIZE);
}
out:
return rc;
@@ -790,7 +789,7 @@ ecryptfs_write_zeros(struct file *file,
page_cache_release(tmp_page);
goto out;
}
- zero_user_page(tmp_page, start, num_zeros, KM_USER0);
+ zero_user(tmp_page, start, num_zeros);
rc = ecryptfs_commit_write(file, tmp_page, start, start + num_zeros);
if (rc < 0) {
ecryptfs_printk(KERN_ERR, "Error attempting to write zero's "
Index: linux-2.6/fs/ext3/inode.c
===================================================================
--- linux-2.6.orig/fs/ext3/inode.c 2007-08-27 19:22:13.000000000 -0700
+++ linux-2.6/fs/ext3/inode.c 2007-08-27 19:22:17.000000000 -0700
@@ -1778,7 +1778,7 @@ static int ext3_block_truncate_page(hand
*/
if (!page_has_buffers(page) && test_opt(inode->i_sb, NOBH) &&
ext3_should_writeback_data(inode) && PageUptodate(page)) {
- zero_user_page(page, offset, length, KM_USER0);
+ zero_user(page, offset, length);
set_page_dirty(page);
goto unlock;
}
@@ -1831,7 +1831,7 @@ static int ext3_block_truncate_page(hand
goto unlock;
}

- zero_user_page(page, offset, length, KM_USER0);
+ zero_user(page, offset, length);
BUFFER_TRACE(bh, "zeroed end of block");

err = 0;
Index: linux-2.6/fs/ext4/inode.c
===================================================================
--- linux-2.6.orig/fs/ext4/inode.c 2007-08-27 19:22:13.000000000 -0700
+++ linux-2.6/fs/ext4/inode.c 2007-08-27 19:22:17.000000000 -0700
@@ -1777,7 +1777,7 @@ int ext4_block_truncate_page(handle_t *h
*/
if (!page_has_buffers(page) && test_opt(inode->i_sb, NOBH) &&
ext4_should_writeback_data(inode) && PageUptodate(page)) {
- zero_user_page(page, offset, length, KM_USER0);
+ zero_user(page, offset, length);
set_page_dirty(page);
goto unlock;
}
@@ -1830,7 +1830,7 @@ int ext4_block_truncate_page(handle_t *h
goto unlock;
}

- zero_user_page(page, offset, length, KM_USER0);
+ zero_user(page, offset, length);

BUFFER_TRACE(bh, "zeroed end of block");

Index: linux-2.6/fs/gfs2/bmap.c
===================================================================
--- linux-2.6.orig/fs/gfs2/bmap.c 2007-08-27 19:22:13.000000000 -0700
+++ linux-2.6/fs/gfs2/bmap.c 2007-08-27 19:22:17.000000000 -0700
@@ -933,7 +933,7 @@ static int gfs2_block_truncate_page(stru
if (sdp->sd_args.ar_data == GFS2_DATA_ORDERED || gfs2_is_jdata(ip))
gfs2_trans_add_bh(ip->i_gl, bh, 0);

- zero_user_page(page, offset, length, KM_USER0);
+ zero_user(page, offset, length);

unlock:
unlock_page(page);
Index: linux-2.6/fs/gfs2/ops_address.c
===================================================================
--- linux-2.6.orig/fs/gfs2/ops_address.c 2007-08-27 19:22:13.000000000 -0700
+++ linux-2.6/fs/gfs2/ops_address.c 2007-08-27 19:22:17.000000000 -0700
@@ -208,7 +208,7 @@ static int stuffed_readpage(struct gfs2_
* so we need to supply one here. It doesn't happen often.
*/
if (unlikely(page->index)) {
- zero_user_page(page, 0, PAGE_CACHE_SIZE, KM_USER0);
+ zero_user(page, 0, PAGE_CACHE_SIZE);
return 0;
}

Index: linux-2.6/fs/libfs.c
===================================================================
--- linux-2.6.orig/fs/libfs.c 2007-08-27 19:22:13.000000000 -0700
+++ linux-2.6/fs/libfs.c 2007-08-27 19:22:17.000000000 -0700
@@ -340,13 +340,10 @@ int simple_prepare_write(struct file *fi
unsigned from, unsigned to)
{
if (!PageUptodate(page)) {
- if (to - from != PAGE_CACHE_SIZE) {
- void *kaddr = kmap_atomic(page, KM_USER0);
- memset(kaddr, 0, from);
- memset(kaddr + to, 0, PAGE_CACHE_SIZE - to);
- flush_dcache_page(page);
- kunmap_atomic(kaddr, KM_USER0);
- }
+ if (to - from != PAGE_CACHE_SIZE)
+ zero_user_segments(page,
+ 0, from,
+ to, PAGE_CACHE_SIZE);
}
return 0;
}
Index: linux-2.6/fs/mpage.c
===================================================================
--- linux-2.6.orig/fs/mpage.c 2007-08-27 19:22:13.000000000 -0700
+++ linux-2.6/fs/mpage.c 2007-08-27 19:22:17.000000000 -0700
@@ -284,9 +284,7 @@ do_mpage_readpage(struct bio *bio, struc
}

if (first_hole != blocks_per_page) {
- zero_user_page(page, first_hole << blkbits,
- PAGE_CACHE_SIZE - (first_hole << blkbits),
- KM_USER0);
+ zero_user_segment(page, first_hole << blkbits, PAGE_CACHE_SIZE);
if (first_hole == 0) {
SetPageUptodate(page);
unlock_page(page);
@@ -585,8 +583,7 @@ page_is_mapped:

if (page->index > end_index || !offset)
goto confused;
- zero_user_page(page, offset, PAGE_CACHE_SIZE - offset,
- KM_USER0);
+ zero_user_segment(page, offset, PAGE_CACHE_SIZE);
}

/*
Index: linux-2.6/fs/nfs/read.c
===================================================================
--- linux-2.6.orig/fs/nfs/read.c 2007-08-27 19:22:13.000000000 -0700
+++ linux-2.6/fs/nfs/read.c 2007-08-27 19:22:17.000000000 -0700
@@ -79,7 +79,7 @@ void nfs_readdata_release(void *data)
static
int nfs_return_empty_page(struct page *page)
{
- zero_user_page(page, 0, PAGE_CACHE_SIZE, KM_USER0);
+ zero_user(page, 0, PAGE_CACHE_SIZE);
SetPageUptodate(page);
unlock_page(page);
return 0;
@@ -103,10 +103,10 @@ static void nfs_readpage_truncate_uninit
pglen = PAGE_CACHE_SIZE - base;
for (;;) {
if (remainder <= pglen) {
- zero_user_page(*pages, base, remainder, KM_USER0);
+ zero_user(*pages, base, remainder);
break;
}
- zero_user_page(*pages, base, pglen, KM_USER0);
+ zero_user(*pages, base, pglen);
pages++;
remainder -= pglen;
pglen = PAGE_CACHE_SIZE;
@@ -130,7 +130,7 @@ static int nfs_readpage_async(struct nfs
return PTR_ERR(new);
}
if (len < PAGE_CACHE_SIZE)
- zero_user_page(page, len, PAGE_CACHE_SIZE - len, KM_USER0);
+ zero_user_segment(page, len, PAGE_CACHE_SIZE);

nfs_list_add_request(new, &one_request);
if (NFS_SERVER(inode)->rsize < PAGE_CACHE_SIZE)
@@ -538,7 +538,7 @@ readpage_async_filler(void *data, struct
goto out_error;

if (len < PAGE_CACHE_SIZE)
- zero_user_page(page, len, PAGE_CACHE_SIZE - len, KM_USER0);
+ zero_user_segment(page, len, PAGE_CACHE_SIZE);
nfs_pageio_add_request(desc->pgio, new);
return 0;
out_error:
Index: linux-2.6/fs/nfs/write.c
===================================================================
--- linux-2.6.orig/fs/nfs/write.c 2007-08-27 19:22:13.000000000 -0700
+++ linux-2.6/fs/nfs/write.c 2007-08-27 19:22:17.000000000 -0700
@@ -168,7 +168,7 @@ static void nfs_mark_uptodate(struct pag
if (count != nfs_page_length(page))
return;
if (count != PAGE_CACHE_SIZE)
- zero_user_page(page, count, PAGE_CACHE_SIZE - count, KM_USER0);
+ zero_user_segment(page, count, PAGE_CACHE_SIZE);
SetPageUptodate(page);
}

Index: linux-2.6/fs/ntfs/aops.c
===================================================================
--- linux-2.6.orig/fs/ntfs/aops.c 2007-08-27 19:22:13.000000000 -0700
+++ linux-2.6/fs/ntfs/aops.c 2007-08-27 19:22:17.000000000 -0700
@@ -87,13 +87,17 @@ static void ntfs_end_buffer_async_read(s
/* Check for the current buffer head overflowing. */
if (unlikely(file_ofs + bh->b_size > init_size)) {
int ofs;
+ void *kaddr;

ofs = 0;
if (file_ofs < init_size)
ofs = init_size - file_ofs;
local_irq_save(flags);
- zero_user_page(page, bh_offset(bh) + ofs,
- bh->b_size - ofs, KM_BIO_SRC_IRQ);
+ kaddr = kmap_atomic(page, KM_BIO_SRC_IRQ);
+ memset(kaddr + bh_offset(bh) + ofs, 0,
+ bh->b_size - ofs);
+ flush_dcache_page(page);
+ kunmap_atomic(kaddr, KM_BIO_SRC_IRQ);
local_irq_restore(flags);
}
} else {
@@ -334,7 +338,7 @@ handle_hole:
bh->b_blocknr = -1UL;
clear_buffer_mapped(bh);
handle_zblock:
- zero_user_page(page, i * blocksize, blocksize, KM_USER0);
+ zero_user(page, i * blocksize, blocksize);
if (likely(!err))
set_buffer_uptodate(bh);
} while (i++, iblock++, (bh = bh->b_this_page) != head);
@@ -451,7 +455,7 @@ retry_readpage:
* ok to ignore the compressed flag here.
*/
if (unlikely(page->index > 0)) {
- zero_user_page(page, 0, PAGE_CACHE_SIZE, KM_USER0);
+ zero_user(page, 0, PAGE_CACHE_SIZE);
goto done;
}
if (!NInoAttr(ni))
@@ -780,8 +784,7 @@ lock_retry_remap:
if (err == -ENOENT || lcn == LCN_ENOENT) {
bh->b_blocknr = -1;
clear_buffer_dirty(bh);
- zero_user_page(page, bh_offset(bh), blocksize,
- KM_USER0);
+ zero_user(page, bh_offset(bh), blocksize);
set_buffer_uptodate(bh);
err = 0;
continue;
@@ -1406,8 +1409,7 @@ retry_writepage:
if (page->index >= (i_size >> PAGE_CACHE_SHIFT)) {
/* The page straddles i_size. */
unsigned int ofs = i_size & ~PAGE_CACHE_MASK;
- zero_user_page(page, ofs, PAGE_CACHE_SIZE - ofs,
- KM_USER0);
+ zero_user_segment(page, ofs, PAGE_CACHE_SIZE);
}
/* Handle mst protected attributes. */
if (NInoMstProtected(ni))
Index: linux-2.6/fs/ntfs/file.c
===================================================================
--- linux-2.6.orig/fs/ntfs/file.c 2007-08-27 19:22:13.000000000 -0700
+++ linux-2.6/fs/ntfs/file.c 2007-08-27 19:22:17.000000000 -0700
@@ -607,8 +607,8 @@ do_next_page:
ntfs_submit_bh_for_read(bh);
*wait_bh++ = bh;
} else {
- zero_user_page(page, bh_offset(bh),
- blocksize, KM_USER0);
+ zero_user(page, bh_offset(bh),
+ blocksize);
set_buffer_uptodate(bh);
}
}
@@ -683,9 +683,8 @@ map_buffer_cached:
ntfs_submit_bh_for_read(bh);
*wait_bh++ = bh;
} else {
- zero_user_page(page,
- bh_offset(bh),
- blocksize, KM_USER0);
+ zero_user(page, bh_offset(bh),
+ blocksize);
set_buffer_uptodate(bh);
}
}
@@ -703,8 +702,8 @@ map_buffer_cached:
*/
if (bh_end <= pos || bh_pos >= end) {
if (!buffer_uptodate(bh)) {
- zero_user_page(page, bh_offset(bh),
- blocksize, KM_USER0);
+ zero_user(page, bh_offset(bh),
+ blocksize);
set_buffer_uptodate(bh);
}
mark_buffer_dirty(bh);
@@ -743,8 +742,7 @@ map_buffer_cached:
if (!buffer_uptodate(bh))
set_buffer_uptodate(bh);
} else if (!buffer_uptodate(bh)) {
- zero_user_page(page, bh_offset(bh), blocksize,
- KM_USER0);
+ zero_user(page, bh_offset(bh), blocksize);
set_buffer_uptodate(bh);
}
continue;
@@ -868,8 +866,8 @@ rl_not_mapped_enoent:
if (!buffer_uptodate(bh))
set_buffer_uptodate(bh);
} else if (!buffer_uptodate(bh)) {
- zero_user_page(page, bh_offset(bh),
- blocksize, KM_USER0);
+ zero_user(page, bh_offset(bh),
+ blocksize);
set_buffer_uptodate(bh);
}
continue;
@@ -1128,8 +1126,8 @@ rl_not_mapped_enoent:

if (likely(bh_pos < initialized_size))
ofs = initialized_size - bh_pos;
- zero_user_page(page, bh_offset(bh) + ofs,
- blocksize - ofs, KM_USER0);
+ zero_user_segment(page, bh_offset(bh) + ofs,
+ blocksize);
}
} else /* if (unlikely(!buffer_uptodate(bh))) */
err = -EIO;
@@ -1269,8 +1267,8 @@ rl_not_mapped_enoent:
if (PageUptodate(page))
set_buffer_uptodate(bh);
else {
- zero_user_page(page, bh_offset(bh),
- blocksize, KM_USER0);
+ zero_user(page, bh_offset(bh),
+ blocksize);
set_buffer_uptodate(bh);
}
}
@@ -1330,7 +1328,7 @@ err_out:
len = PAGE_CACHE_SIZE;
if (len > bytes)
len = bytes;
- zero_user_page(*pages, 0, len, KM_USER0);
+ zero_user(*pages, 0, len);
}
goto out;
}
@@ -1451,7 +1449,7 @@ err_out:
len = PAGE_CACHE_SIZE;
if (len > bytes)
len = bytes;
- zero_user_page(*pages, 0, len, KM_USER0);
+ zero_user(*pages, 0, len);
}
goto out;
}
Index: linux-2.6/fs/ocfs2/aops.c
===================================================================
--- linux-2.6.orig/fs/ocfs2/aops.c 2007-08-27 19:22:13.000000000 -0700
+++ linux-2.6/fs/ocfs2/aops.c 2007-08-27 19:22:17.000000000 -0700
@@ -238,7 +238,7 @@ static int ocfs2_readpage(struct file *f
* XXX sys_readahead() seems to get that wrong?
*/
if (start >= i_size_read(inode)) {
- zero_user_page(page, 0, PAGE_SIZE, KM_USER0);
+ zero_user(page, 0, PAGE_SIZE);
SetPageUptodate(page);
ret = 0;
goto out_alloc;
@@ -746,7 +746,7 @@ int ocfs2_map_page_blocks(struct page *p
if (block_start >= to)
break;

- zero_user_page(page, block_start, bh->b_size, KM_USER0);
+ zero_user(page, block_start, bh->b_size);
set_buffer_uptodate(bh);
mark_buffer_dirty(bh);

@@ -905,7 +905,7 @@ static void ocfs2_zero_new_buffers(struc
start = max(from, block_start);
end = min(to, block_end);

- zero_user_page(page, start, end - start, KM_USER0);
+ zero_user_segment(page, start, end);
set_buffer_uptodate(bh);
}

Index: linux-2.6/fs/reiserfs/inode.c
===================================================================
--- linux-2.6.orig/fs/reiserfs/inode.c 2007-08-27 19:22:13.000000000 -0700
+++ linux-2.6/fs/reiserfs/inode.c 2007-08-27 19:22:17.000000000 -0700
@@ -2150,7 +2150,7 @@ int reiserfs_truncate_file(struct inode
/* if we are not on a block boundary */
if (length) {
length = blocksize - length;
- zero_user_page(page, offset, length, KM_USER0);
+ zero_user(page, offset, length);
if (buffer_mapped(bh) && bh->b_blocknr != 0) {
mark_buffer_dirty(bh);
}
@@ -2374,7 +2374,7 @@ static int reiserfs_write_full_page(stru
unlock_page(page);
return 0;
}
- zero_user_page(page, last_offset, PAGE_CACHE_SIZE - last_offset, KM_USER0);
+ zero_user_segment(page, last_offset, PAGE_CACHE_SIZE);
}
bh = head;
block = page->index << (PAGE_CACHE_SHIFT - s->s_blocksize_bits);
Index: linux-2.6/fs/xfs/linux-2.6/xfs_lrw.c
===================================================================
--- linux-2.6.orig/fs/xfs/linux-2.6/xfs_lrw.c 2007-08-27 19:22:13.000000000 -0700
+++ linux-2.6/fs/xfs/linux-2.6/xfs_lrw.c 2007-08-27 19:22:17.000000000 -0700
@@ -159,7 +159,7 @@ xfs_iozero(
if (status)
goto unlock;

- zero_user_page(page, offset, bytes, KM_USER0);
+ zero_user(page, offset, bytes);

status = mapping->a_ops->commit_write(NULL, page, offset,
offset + bytes);
Index: linux-2.6/include/linux/highmem.h
===================================================================
--- linux-2.6.orig/include/linux/highmem.h 2007-08-27 19:22:13.000000000 -0700
+++ linux-2.6/include/linux/highmem.h 2007-08-27 19:22:17.000000000 -0700
@@ -124,28 +124,41 @@ static inline void clear_highpage(struct
kunmap_atomic(kaddr, KM_USER0);
}

-/*
- * Same but also flushes aliased cache contents to RAM.
- *
- * This must be a macro because KM_USER0 and friends aren't defined if
- * !CONFIG_HIGHMEM
- */
-#define zero_user_page(page, offset, size, km_type) \
- do { \
- void *kaddr; \
- \
- BUG_ON((offset) + (size) > PAGE_SIZE); \
- \
- kaddr = kmap_atomic(page, km_type); \
- memset((char *)kaddr + (offset), 0, (size)); \
- flush_dcache_page(page); \
- kunmap_atomic(kaddr, (km_type)); \
- } while (0)
+static inline void zero_user_segments(struct page *page,
+ unsigned start1, unsigned end1,
+ unsigned start2, unsigned end2)
+{
+ void *kaddr = kmap_atomic(page, KM_USER0);
+
+ BUG_ON(end1 > PAGE_SIZE ||
+ end2 > PAGE_SIZE);
+
+ if (end1 > start1)
+ memset(kaddr + start1, 0, end1 - start1);
+
+ if (end2 > start2)
+ memset(kaddr + start2, 0, end2 - start2);
+
+ kunmap_atomic(kaddr, KM_USER0);
+ flush_dcache_page(page);
+}
+
+static inline void zero_user_segment(struct page *page,
+ unsigned start, unsigned end)
+{
+ zero_user_segments(page, start, end, 0, 0);
+}
+
+static inline void zero_user(struct page *page,
+ unsigned start, unsigned size)
+{
+ zero_user_segments(page, start, start + size, 0, 0);
+}

static inline void __deprecated memclear_highpage_flush(struct page *page,
unsigned int offset, unsigned int size)
{
- zero_user_page(page, offset, size, KM_USER0);
+ zero_user(page, offset, size);
}

#ifndef __HAVE_ARCH_COPY_USER_HIGHPAGE
Index: linux-2.6/mm/filemap_xip.c
===================================================================
--- linux-2.6.orig/mm/filemap_xip.c 2007-08-27 19:22:13.000000000 -0700
+++ linux-2.6/mm/filemap_xip.c 2007-08-27 19:22:17.000000000 -0700
@@ -433,7 +433,7 @@ xip_truncate_page(struct address_space *
else
return PTR_ERR(page);
}
- zero_user_page(page, offset, length, KM_USER0);
+ zero_user(page, offset, length);
return 0;
}
EXPORT_SYMBOL_GPL(xip_truncate_page);
Index: linux-2.6/mm/truncate.c
===================================================================
--- linux-2.6.orig/mm/truncate.c 2007-08-27 19:22:13.000000000 -0700
+++ linux-2.6/mm/truncate.c 2007-08-27 19:22:17.000000000 -0700
@@ -47,7 +47,7 @@ void do_invalidatepage(struct page *page

static inline void truncate_partial_page(struct page *page, unsigned partial)
{
- zero_user_page(page, partial, PAGE_CACHE_SIZE - partial, KM_USER0);
+ zero_user_segment(page, partial, PAGE_CACHE_SIZE);
if (PagePrivate(page))
do_invalidatepage(page, partial);
}
Index: linux-2.6/fs/affs/file.c
===================================================================
--- linux-2.6.orig/fs/affs/file.c 2007-08-27 19:22:39.000000000 -0700
+++ linux-2.6/fs/affs/file.c 2007-08-27 19:23:05.000000000 -0700
@@ -628,7 +628,7 @@ static int affs_prepare_write_ofs(struct
return err;
}
if (to < PAGE_CACHE_SIZE) {
- zero_user_page(page, to, PAGE_CACHE_SIZE - to, KM_USER0);
+ zero_user_segment(page, to, PAGE_CACHE_SIZE);
if (size > offset + to) {
if (size < offset + PAGE_CACHE_SIZE)
tmp = size & ~PAGE_CACHE_MASK;
Index: linux-2.6/fs/reiserfs/file.c
===================================================================
--- linux-2.6.orig/fs/reiserfs/file.c 2007-08-27 19:23:15.000000000 -0700
+++ linux-2.6/fs/reiserfs/file.c 2007-08-27 19:24:31.000000000 -0700
@@ -1060,11 +1060,11 @@ static int reiserfs_prepare_file_region_
parts of first and last pages in write area (if needed) */
if ((pos & ~((loff_t) PAGE_CACHE_SIZE - 1)) > inode->i_size) {
if (from != 0) /* First page needs to be partially zeroed */
- zero_user_page(prepared_pages[0], 0, from, KM_USER0);
+ zero_user(prepared_pages[0], 0, from);

if (to != PAGE_CACHE_SIZE) /* Last page needs to be partially zeroed */
- zero_user_page(prepared_pages[num_pages-1], to,
- PAGE_CACHE_SIZE - to, KM_USER0);
+ zero_user_segment(prepared_pages[num_pages-1], to,
+ PAGE_CACHE_SIZE);

/* Since all blocks are new - use already calculated value */
return blocks;
@@ -1191,9 +1191,8 @@ static int reiserfs_prepare_file_region_
ll_rw_block(READ, 1, &bh);
*wait_bh++ = bh;
} else { /* Not mapped, zero it */
- zero_user_page(prepared_pages[0],
- block_start,
- from - block_start, KM_USER0);
+ zero_user_segment(prepared_pages[0],
+ block_start, from);
set_buffer_uptodate(bh);
}
}
@@ -1225,8 +1224,8 @@ static int reiserfs_prepare_file_region_
ll_rw_block(READ, 1, &bh);
*wait_bh++ = bh;
} else { /* Not mapped, zero it */
- zero_user_page(prepared_pages[num_pages-1],
- to, block_end - to, KM_USER0);
+ zero_user_segment(prepared_pages[num_pages-1],
+ to, block_end);
set_buffer_uptodate(bh);
}
}

--