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ocfs2: Small refactor of truncate zeroing code

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We'll want to reuse most of this when pushing inline data back out to an
extent. Keeping this part as a seperate patch helps to keep the upcoming
changes for write support uncluttered.

The core portion of ocfs2_zero_cluster_pages() responsible for making sure a
page is mapped and properly dirtied is abstracted out into it's own
function, ocfs2_map_and_dirty_page(). Actual functionality doesn't change,
though zeroing becomes optional.

We also turn part of ocfs2_free_write_ctxt() into  a common function for
unlocking and freeing a page array. This operation is very common (and
uniform) for Ocfs2 cluster sizes greater than page size, so it makes sense
to keep the code in one place.

Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
Reviewed-by: Joel Becker <joel.becker@oracle.com>
This commit is contained in:
Mark Fasheh 2007-09-07 14:20:45 -07:00
parent 65ed39d6ca
commit 1d410a6e33
3 changed files with 86 additions and 87 deletions
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151
fs/ocfs2/alloc.c
View file

@ -5633,12 +5633,50 @@ static int ocfs2_ordered_zero_func(handle_t *handle, struct buffer_head *bh)
return ocfs2_journal_dirty_data(handle, bh);
}
static void ocfs2_map_and_dirty_page(struct inode *inode, handle_t *handle,
unsigned int from, unsigned int to,
struct page *page, int zero, u64 *phys)
{
int ret, partial = 0;
ret = ocfs2_map_page_blocks(page, phys, inode, from, to, 0);
if (ret)
mlog_errno(ret);
if (zero)
zero_user_page(page, from, to - from, KM_USER0);
/*
* Need to set the buffers we zero'd into uptodate
* here if they aren't - ocfs2_map_page_blocks()
* might've skipped some
*/
if (ocfs2_should_order_data(inode)) {
ret = walk_page_buffers(handle,
page_buffers(page),
from, to, &partial,
ocfs2_ordered_zero_func);
if (ret < 0)
mlog_errno(ret);
} else {
ret = walk_page_buffers(handle, page_buffers(page),
from, to, &partial,
ocfs2_writeback_zero_func);
if (ret < 0)
mlog_errno(ret);
}
if (!partial)
SetPageUptodate(page);
flush_dcache_page(page);
}
static void ocfs2_zero_cluster_pages(struct inode *inode, loff_t start,
loff_t end, struct page **pages,
int numpages, u64 phys, handle_t *handle)
{
int i, ret, partial = 0;
void *kaddr;
int i;
struct page *page;
unsigned int from, to = PAGE_CACHE_SIZE;
struct super_block *sb = inode->i_sb;
@ -5659,87 +5697,31 @@ static void ocfs2_zero_cluster_pages(struct inode *inode, loff_t start,
BUG_ON(from > PAGE_CACHE_SIZE);
BUG_ON(to > PAGE_CACHE_SIZE);
ret = ocfs2_map_page_blocks(page, &phys, inode, from, to, 0);
if (ret)
mlog_errno(ret);
kaddr = kmap_atomic(page, KM_USER0);
memset(kaddr + from, 0, to - from);
kunmap_atomic(kaddr, KM_USER0);
/*
* Need to set the buffers we zero'd into uptodate
* here if they aren't - ocfs2_map_page_blocks()
* might've skipped some
*/
if (ocfs2_should_order_data(inode)) {
ret = walk_page_buffers(handle,
page_buffers(page),
from, to, &partial,
ocfs2_ordered_zero_func);
if (ret < 0)
mlog_errno(ret);
} else {
ret = walk_page_buffers(handle, page_buffers(page),
from, to, &partial,
ocfs2_writeback_zero_func);
if (ret < 0)
mlog_errno(ret);
}
if (!partial)
SetPageUptodate(page);
flush_dcache_page(page);
ocfs2_map_and_dirty_page(inode, handle, from, to, page, 1,
&phys);
start = (page->index + 1) << PAGE_CACHE_SHIFT;
}
out:
if (pages) {
for (i = 0; i < numpages; i++) {
page = pages[i];
unlock_page(page);
mark_page_accessed(page);
page_cache_release(page);
}
}
if (pages)
ocfs2_unlock_and_free_pages(pages, numpages);
}
static int ocfs2_grab_eof_pages(struct inode *inode, loff_t start, loff_t end,
struct page **pages, int *num, u64 *phys)
struct page **pages, int *num)
{
int i, numpages = 0, ret = 0;
unsigned int ext_flags;
int numpages, ret = 0;
struct super_block *sb = inode->i_sb;
struct address_space *mapping = inode->i_mapping;
unsigned long index;
loff_t last_page_bytes;
BUG_ON(!ocfs2_sparse_alloc(OCFS2_SB(sb)));
BUG_ON(start > end);
if (start == end)
goto out;
BUG_ON(start >> OCFS2_SB(sb)->s_clustersize_bits !=
(end - 1) >> OCFS2_SB(sb)->s_clustersize_bits);
ret = ocfs2_extent_map_get_blocks(inode, start >> sb->s_blocksize_bits,
phys, NULL, &ext_flags);
if (ret) {
mlog_errno(ret);
goto out;
}
/* Tail is a hole. */
if (*phys == 0)
goto out;
/* Tail is marked as unwritten, we can count on write to zero
* in that case. */
if (ext_flags & OCFS2_EXT_UNWRITTEN)
goto out;
numpages = 0;
last_page_bytes = PAGE_ALIGN(end);
index = start >> PAGE_CACHE_SHIFT;
do {
@ -5756,14 +5738,8 @@ static int ocfs2_grab_eof_pages(struct inode *inode, loff_t start, loff_t end,
out:
if (ret != 0) {
if (pages) {
for (i = 0; i < numpages; i++) {
if (pages[i]) {
unlock_page(pages[i]);
page_cache_release(pages[i]);
}
}
}
if (pages)
ocfs2_unlock_and_free_pages(pages, numpages);
numpages = 0;
}
@ -5784,18 +5760,20 @@ out:
int ocfs2_zero_range_for_truncate(struct inode *inode, handle_t *handle,
u64 range_start, u64 range_end)
{
int ret, numpages;
int ret = 0, numpages;
struct page **pages = NULL;
u64 phys;
unsigned int ext_flags;
struct super_block *sb = inode->i_sb;
/*
* File systems which don't support sparse files zero on every
* extend.
*/
if (!ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb)))
if (!ocfs2_sparse_alloc(OCFS2_SB(sb)))
return 0;
pages = kcalloc(ocfs2_pages_per_cluster(inode->i_sb),
pages = kcalloc(ocfs2_pages_per_cluster(sb),
sizeof(struct page *), GFP_NOFS);
if (pages == NULL) {
ret = -ENOMEM;
@ -5803,16 +5781,31 @@ int ocfs2_zero_range_for_truncate(struct inode *inode, handle_t *handle,
goto out;
}
ret = ocfs2_grab_eof_pages(inode, range_start, range_end, pages,
&numpages, &phys);
if (range_start == range_end)
goto out;
ret = ocfs2_extent_map_get_blocks(inode,
range_start >> sb->s_blocksize_bits,
&phys, NULL, &ext_flags);
if (ret) {
mlog_errno(ret);
goto out;
}
if (numpages == 0)
/*
* Tail is a hole, or is marked unwritten. In either case, we
* can count on read and write to return/push zero's.
*/
if (phys == 0 || ext_flags & OCFS2_EXT_UNWRITTEN)
goto out;
ret = ocfs2_grab_eof_pages(inode, range_start, range_end, pages,
&numpages);
if (ret) {
mlog_errno(ret);
goto out;
}
ocfs2_zero_cluster_pages(inode, range_start, range_end, pages,
numpages, phys, handle);

20
fs/ocfs2/aops.c
View file

@ -830,18 +830,22 @@ struct ocfs2_write_ctxt {
struct ocfs2_cached_dealloc_ctxt w_dealloc;
};
static void ocfs2_free_write_ctxt(struct ocfs2_write_ctxt *wc)
void ocfs2_unlock_and_free_pages(struct page **pages, int num_pages)
{
int i;
for(i = 0; i < wc->w_num_pages; i++) {
if (wc->w_pages[i] == NULL)
continue;
unlock_page(wc->w_pages[i]);
mark_page_accessed(wc->w_pages[i]);
page_cache_release(wc->w_pages[i]);
for(i = 0; i < num_pages; i++) {
if (pages[i]) {
unlock_page(pages[i]);
mark_page_accessed(pages[i]);
page_cache_release(pages[i]);
}
}
}
static void ocfs2_free_write_ctxt(struct ocfs2_write_ctxt *wc)
{
ocfs2_unlock_and_free_pages(wc->w_pages, wc->w_num_pages);
brelse(wc->w_di_bh);
kfree(wc);

2
fs/ocfs2/aops.h
View file

@ -34,6 +34,8 @@ int ocfs2_map_page_blocks(struct page *page, u64 *p_blkno,
struct inode *inode, unsigned int from,
unsigned int to, int new);
void ocfs2_unlock_and_free_pages(struct page **pages, int num_pages);
int walk_page_buffers( handle_t *handle,
struct buffer_head *head,
unsigned from,