mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-27 19:29:37 +00:00
![Steven Whitehouse](/assets/img/avatar_default.png)
We recently fixed the writeback of pages prior to performing direct i/o, however the initial fix was perhaps a bit heavy handed. There is no need to invalidate pages if the direct i/o is only a read, since they will be identical to what has been flushed to disk anyway. Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
1173 lines
30 KiB
C
1173 lines
30 KiB
C
/*
|
|
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
|
|
* Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
|
|
*
|
|
* This copyrighted material is made available to anyone wishing to use,
|
|
* modify, copy, or redistribute it subject to the terms and conditions
|
|
* of the GNU General Public License version 2.
|
|
*/
|
|
|
|
#include <linux/sched.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/completion.h>
|
|
#include <linux/buffer_head.h>
|
|
#include <linux/pagemap.h>
|
|
#include <linux/pagevec.h>
|
|
#include <linux/mpage.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/writeback.h>
|
|
#include <linux/swap.h>
|
|
#include <linux/gfs2_ondisk.h>
|
|
#include <linux/backing-dev.h>
|
|
#include <linux/aio.h>
|
|
|
|
#include "gfs2.h"
|
|
#include "incore.h"
|
|
#include "bmap.h"
|
|
#include "glock.h"
|
|
#include "inode.h"
|
|
#include "log.h"
|
|
#include "meta_io.h"
|
|
#include "quota.h"
|
|
#include "trans.h"
|
|
#include "rgrp.h"
|
|
#include "super.h"
|
|
#include "util.h"
|
|
#include "glops.h"
|
|
|
|
|
|
static void gfs2_page_add_databufs(struct gfs2_inode *ip, struct page *page,
|
|
unsigned int from, unsigned int to)
|
|
{
|
|
struct buffer_head *head = page_buffers(page);
|
|
unsigned int bsize = head->b_size;
|
|
struct buffer_head *bh;
|
|
unsigned int start, end;
|
|
|
|
for (bh = head, start = 0; bh != head || !start;
|
|
bh = bh->b_this_page, start = end) {
|
|
end = start + bsize;
|
|
if (end <= from || start >= to)
|
|
continue;
|
|
if (gfs2_is_jdata(ip))
|
|
set_buffer_uptodate(bh);
|
|
gfs2_trans_add_data(ip->i_gl, bh);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* gfs2_get_block_noalloc - Fills in a buffer head with details about a block
|
|
* @inode: The inode
|
|
* @lblock: The block number to look up
|
|
* @bh_result: The buffer head to return the result in
|
|
* @create: Non-zero if we may add block to the file
|
|
*
|
|
* Returns: errno
|
|
*/
|
|
|
|
static int gfs2_get_block_noalloc(struct inode *inode, sector_t lblock,
|
|
struct buffer_head *bh_result, int create)
|
|
{
|
|
int error;
|
|
|
|
error = gfs2_block_map(inode, lblock, bh_result, 0);
|
|
if (error)
|
|
return error;
|
|
if (!buffer_mapped(bh_result))
|
|
return -EIO;
|
|
return 0;
|
|
}
|
|
|
|
static int gfs2_get_block_direct(struct inode *inode, sector_t lblock,
|
|
struct buffer_head *bh_result, int create)
|
|
{
|
|
return gfs2_block_map(inode, lblock, bh_result, 0);
|
|
}
|
|
|
|
/**
|
|
* gfs2_writepage_common - Common bits of writepage
|
|
* @page: The page to be written
|
|
* @wbc: The writeback control
|
|
*
|
|
* Returns: 1 if writepage is ok, otherwise an error code or zero if no error.
|
|
*/
|
|
|
|
static int gfs2_writepage_common(struct page *page,
|
|
struct writeback_control *wbc)
|
|
{
|
|
struct inode *inode = page->mapping->host;
|
|
struct gfs2_inode *ip = GFS2_I(inode);
|
|
struct gfs2_sbd *sdp = GFS2_SB(inode);
|
|
loff_t i_size = i_size_read(inode);
|
|
pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
|
|
unsigned offset;
|
|
|
|
if (gfs2_assert_withdraw(sdp, gfs2_glock_is_held_excl(ip->i_gl)))
|
|
goto out;
|
|
if (current->journal_info)
|
|
goto redirty;
|
|
/* Is the page fully outside i_size? (truncate in progress) */
|
|
offset = i_size & (PAGE_CACHE_SIZE-1);
|
|
if (page->index > end_index || (page->index == end_index && !offset)) {
|
|
page->mapping->a_ops->invalidatepage(page, 0, PAGE_CACHE_SIZE);
|
|
goto out;
|
|
}
|
|
return 1;
|
|
redirty:
|
|
redirty_page_for_writepage(wbc, page);
|
|
out:
|
|
unlock_page(page);
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* gfs2_writepage - Write page for writeback mappings
|
|
* @page: The page
|
|
* @wbc: The writeback control
|
|
*
|
|
*/
|
|
|
|
static int gfs2_writepage(struct page *page, struct writeback_control *wbc)
|
|
{
|
|
int ret;
|
|
|
|
ret = gfs2_writepage_common(page, wbc);
|
|
if (ret <= 0)
|
|
return ret;
|
|
|
|
return nobh_writepage(page, gfs2_get_block_noalloc, wbc);
|
|
}
|
|
|
|
/**
|
|
* __gfs2_jdata_writepage - The core of jdata writepage
|
|
* @page: The page to write
|
|
* @wbc: The writeback control
|
|
*
|
|
* This is shared between writepage and writepages and implements the
|
|
* core of the writepage operation. If a transaction is required then
|
|
* PageChecked will have been set and the transaction will have
|
|
* already been started before this is called.
|
|
*/
|
|
|
|
static int __gfs2_jdata_writepage(struct page *page, struct writeback_control *wbc)
|
|
{
|
|
struct inode *inode = page->mapping->host;
|
|
struct gfs2_inode *ip = GFS2_I(inode);
|
|
struct gfs2_sbd *sdp = GFS2_SB(inode);
|
|
|
|
if (PageChecked(page)) {
|
|
ClearPageChecked(page);
|
|
if (!page_has_buffers(page)) {
|
|
create_empty_buffers(page, inode->i_sb->s_blocksize,
|
|
(1 << BH_Dirty)|(1 << BH_Uptodate));
|
|
}
|
|
gfs2_page_add_databufs(ip, page, 0, sdp->sd_vfs->s_blocksize-1);
|
|
}
|
|
return block_write_full_page(page, gfs2_get_block_noalloc, wbc);
|
|
}
|
|
|
|
/**
|
|
* gfs2_jdata_writepage - Write complete page
|
|
* @page: Page to write
|
|
*
|
|
* Returns: errno
|
|
*
|
|
*/
|
|
|
|
static int gfs2_jdata_writepage(struct page *page, struct writeback_control *wbc)
|
|
{
|
|
struct inode *inode = page->mapping->host;
|
|
struct gfs2_sbd *sdp = GFS2_SB(inode);
|
|
int ret;
|
|
int done_trans = 0;
|
|
|
|
if (PageChecked(page)) {
|
|
if (wbc->sync_mode != WB_SYNC_ALL)
|
|
goto out_ignore;
|
|
ret = gfs2_trans_begin(sdp, RES_DINODE + 1, 0);
|
|
if (ret)
|
|
goto out_ignore;
|
|
done_trans = 1;
|
|
}
|
|
ret = gfs2_writepage_common(page, wbc);
|
|
if (ret > 0)
|
|
ret = __gfs2_jdata_writepage(page, wbc);
|
|
if (done_trans)
|
|
gfs2_trans_end(sdp);
|
|
return ret;
|
|
|
|
out_ignore:
|
|
redirty_page_for_writepage(wbc, page);
|
|
unlock_page(page);
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* gfs2_writepages - Write a bunch of dirty pages back to disk
|
|
* @mapping: The mapping to write
|
|
* @wbc: Write-back control
|
|
*
|
|
* Used for both ordered and writeback modes.
|
|
*/
|
|
static int gfs2_writepages(struct address_space *mapping,
|
|
struct writeback_control *wbc)
|
|
{
|
|
return mpage_writepages(mapping, wbc, gfs2_get_block_noalloc);
|
|
}
|
|
|
|
/**
|
|
* gfs2_write_jdata_pagevec - Write back a pagevec's worth of pages
|
|
* @mapping: The mapping
|
|
* @wbc: The writeback control
|
|
* @writepage: The writepage function to call for each page
|
|
* @pvec: The vector of pages
|
|
* @nr_pages: The number of pages to write
|
|
*
|
|
* Returns: non-zero if loop should terminate, zero otherwise
|
|
*/
|
|
|
|
static int gfs2_write_jdata_pagevec(struct address_space *mapping,
|
|
struct writeback_control *wbc,
|
|
struct pagevec *pvec,
|
|
int nr_pages, pgoff_t end)
|
|
{
|
|
struct inode *inode = mapping->host;
|
|
struct gfs2_sbd *sdp = GFS2_SB(inode);
|
|
loff_t i_size = i_size_read(inode);
|
|
pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
|
|
unsigned offset = i_size & (PAGE_CACHE_SIZE-1);
|
|
unsigned nrblocks = nr_pages * (PAGE_CACHE_SIZE/inode->i_sb->s_blocksize);
|
|
int i;
|
|
int ret;
|
|
|
|
ret = gfs2_trans_begin(sdp, nrblocks, nrblocks);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
for(i = 0; i < nr_pages; i++) {
|
|
struct page *page = pvec->pages[i];
|
|
|
|
lock_page(page);
|
|
|
|
if (unlikely(page->mapping != mapping)) {
|
|
unlock_page(page);
|
|
continue;
|
|
}
|
|
|
|
if (!wbc->range_cyclic && page->index > end) {
|
|
ret = 1;
|
|
unlock_page(page);
|
|
continue;
|
|
}
|
|
|
|
if (wbc->sync_mode != WB_SYNC_NONE)
|
|
wait_on_page_writeback(page);
|
|
|
|
if (PageWriteback(page) ||
|
|
!clear_page_dirty_for_io(page)) {
|
|
unlock_page(page);
|
|
continue;
|
|
}
|
|
|
|
/* Is the page fully outside i_size? (truncate in progress) */
|
|
if (page->index > end_index || (page->index == end_index && !offset)) {
|
|
page->mapping->a_ops->invalidatepage(page, 0,
|
|
PAGE_CACHE_SIZE);
|
|
unlock_page(page);
|
|
continue;
|
|
}
|
|
|
|
ret = __gfs2_jdata_writepage(page, wbc);
|
|
|
|
if (ret || (--(wbc->nr_to_write) <= 0))
|
|
ret = 1;
|
|
}
|
|
gfs2_trans_end(sdp);
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* gfs2_write_cache_jdata - Like write_cache_pages but different
|
|
* @mapping: The mapping to write
|
|
* @wbc: The writeback control
|
|
* @writepage: The writepage function to call
|
|
* @data: The data to pass to writepage
|
|
*
|
|
* The reason that we use our own function here is that we need to
|
|
* start transactions before we grab page locks. This allows us
|
|
* to get the ordering right.
|
|
*/
|
|
|
|
static int gfs2_write_cache_jdata(struct address_space *mapping,
|
|
struct writeback_control *wbc)
|
|
{
|
|
int ret = 0;
|
|
int done = 0;
|
|
struct pagevec pvec;
|
|
int nr_pages;
|
|
pgoff_t index;
|
|
pgoff_t end;
|
|
int scanned = 0;
|
|
int range_whole = 0;
|
|
|
|
pagevec_init(&pvec, 0);
|
|
if (wbc->range_cyclic) {
|
|
index = mapping->writeback_index; /* Start from prev offset */
|
|
end = -1;
|
|
} else {
|
|
index = wbc->range_start >> PAGE_CACHE_SHIFT;
|
|
end = wbc->range_end >> PAGE_CACHE_SHIFT;
|
|
if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
|
|
range_whole = 1;
|
|
scanned = 1;
|
|
}
|
|
|
|
retry:
|
|
while (!done && (index <= end) &&
|
|
(nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
|
|
PAGECACHE_TAG_DIRTY,
|
|
min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1))) {
|
|
scanned = 1;
|
|
ret = gfs2_write_jdata_pagevec(mapping, wbc, &pvec, nr_pages, end);
|
|
if (ret)
|
|
done = 1;
|
|
if (ret > 0)
|
|
ret = 0;
|
|
|
|
pagevec_release(&pvec);
|
|
cond_resched();
|
|
}
|
|
|
|
if (!scanned && !done) {
|
|
/*
|
|
* We hit the last page and there is more work to be done: wrap
|
|
* back to the start of the file
|
|
*/
|
|
scanned = 1;
|
|
index = 0;
|
|
goto retry;
|
|
}
|
|
|
|
if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
|
|
mapping->writeback_index = index;
|
|
return ret;
|
|
}
|
|
|
|
|
|
/**
|
|
* gfs2_jdata_writepages - Write a bunch of dirty pages back to disk
|
|
* @mapping: The mapping to write
|
|
* @wbc: The writeback control
|
|
*
|
|
*/
|
|
|
|
static int gfs2_jdata_writepages(struct address_space *mapping,
|
|
struct writeback_control *wbc)
|
|
{
|
|
struct gfs2_inode *ip = GFS2_I(mapping->host);
|
|
struct gfs2_sbd *sdp = GFS2_SB(mapping->host);
|
|
int ret;
|
|
|
|
ret = gfs2_write_cache_jdata(mapping, wbc);
|
|
if (ret == 0 && wbc->sync_mode == WB_SYNC_ALL) {
|
|
gfs2_log_flush(sdp, ip->i_gl);
|
|
ret = gfs2_write_cache_jdata(mapping, wbc);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* stuffed_readpage - Fill in a Linux page with stuffed file data
|
|
* @ip: the inode
|
|
* @page: the page
|
|
*
|
|
* Returns: errno
|
|
*/
|
|
|
|
static int stuffed_readpage(struct gfs2_inode *ip, struct page *page)
|
|
{
|
|
struct buffer_head *dibh;
|
|
u64 dsize = i_size_read(&ip->i_inode);
|
|
void *kaddr;
|
|
int error;
|
|
|
|
/*
|
|
* Due to the order of unstuffing files and ->fault(), we can be
|
|
* asked for a zero page in the case of a stuffed file being extended,
|
|
* so we need to supply one here. It doesn't happen often.
|
|
*/
|
|
if (unlikely(page->index)) {
|
|
zero_user(page, 0, PAGE_CACHE_SIZE);
|
|
SetPageUptodate(page);
|
|
return 0;
|
|
}
|
|
|
|
error = gfs2_meta_inode_buffer(ip, &dibh);
|
|
if (error)
|
|
return error;
|
|
|
|
kaddr = kmap_atomic(page);
|
|
if (dsize > (dibh->b_size - sizeof(struct gfs2_dinode)))
|
|
dsize = (dibh->b_size - sizeof(struct gfs2_dinode));
|
|
memcpy(kaddr, dibh->b_data + sizeof(struct gfs2_dinode), dsize);
|
|
memset(kaddr + dsize, 0, PAGE_CACHE_SIZE - dsize);
|
|
kunmap_atomic(kaddr);
|
|
flush_dcache_page(page);
|
|
brelse(dibh);
|
|
SetPageUptodate(page);
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/**
|
|
* __gfs2_readpage - readpage
|
|
* @file: The file to read a page for
|
|
* @page: The page to read
|
|
*
|
|
* This is the core of gfs2's readpage. Its used by the internal file
|
|
* reading code as in that case we already hold the glock. Also its
|
|
* called by gfs2_readpage() once the required lock has been granted.
|
|
*
|
|
*/
|
|
|
|
static int __gfs2_readpage(void *file, struct page *page)
|
|
{
|
|
struct gfs2_inode *ip = GFS2_I(page->mapping->host);
|
|
struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host);
|
|
int error;
|
|
|
|
if (gfs2_is_stuffed(ip)) {
|
|
error = stuffed_readpage(ip, page);
|
|
unlock_page(page);
|
|
} else {
|
|
error = mpage_readpage(page, gfs2_block_map);
|
|
}
|
|
|
|
if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
|
|
return -EIO;
|
|
|
|
return error;
|
|
}
|
|
|
|
/**
|
|
* gfs2_readpage - read a page of a file
|
|
* @file: The file to read
|
|
* @page: The page of the file
|
|
*
|
|
* This deals with the locking required. We have to unlock and
|
|
* relock the page in order to get the locking in the right
|
|
* order.
|
|
*/
|
|
|
|
static int gfs2_readpage(struct file *file, struct page *page)
|
|
{
|
|
struct address_space *mapping = page->mapping;
|
|
struct gfs2_inode *ip = GFS2_I(mapping->host);
|
|
struct gfs2_holder gh;
|
|
int error;
|
|
|
|
unlock_page(page);
|
|
gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
|
|
error = gfs2_glock_nq(&gh);
|
|
if (unlikely(error))
|
|
goto out;
|
|
error = AOP_TRUNCATED_PAGE;
|
|
lock_page(page);
|
|
if (page->mapping == mapping && !PageUptodate(page))
|
|
error = __gfs2_readpage(file, page);
|
|
else
|
|
unlock_page(page);
|
|
gfs2_glock_dq(&gh);
|
|
out:
|
|
gfs2_holder_uninit(&gh);
|
|
if (error && error != AOP_TRUNCATED_PAGE)
|
|
lock_page(page);
|
|
return error;
|
|
}
|
|
|
|
/**
|
|
* gfs2_internal_read - read an internal file
|
|
* @ip: The gfs2 inode
|
|
* @buf: The buffer to fill
|
|
* @pos: The file position
|
|
* @size: The amount to read
|
|
*
|
|
*/
|
|
|
|
int gfs2_internal_read(struct gfs2_inode *ip, char *buf, loff_t *pos,
|
|
unsigned size)
|
|
{
|
|
struct address_space *mapping = ip->i_inode.i_mapping;
|
|
unsigned long index = *pos / PAGE_CACHE_SIZE;
|
|
unsigned offset = *pos & (PAGE_CACHE_SIZE - 1);
|
|
unsigned copied = 0;
|
|
unsigned amt;
|
|
struct page *page;
|
|
void *p;
|
|
|
|
do {
|
|
amt = size - copied;
|
|
if (offset + size > PAGE_CACHE_SIZE)
|
|
amt = PAGE_CACHE_SIZE - offset;
|
|
page = read_cache_page(mapping, index, __gfs2_readpage, NULL);
|
|
if (IS_ERR(page))
|
|
return PTR_ERR(page);
|
|
p = kmap_atomic(page);
|
|
memcpy(buf + copied, p + offset, amt);
|
|
kunmap_atomic(p);
|
|
mark_page_accessed(page);
|
|
page_cache_release(page);
|
|
copied += amt;
|
|
index++;
|
|
offset = 0;
|
|
} while(copied < size);
|
|
(*pos) += size;
|
|
return size;
|
|
}
|
|
|
|
/**
|
|
* gfs2_readpages - Read a bunch of pages at once
|
|
*
|
|
* Some notes:
|
|
* 1. This is only for readahead, so we can simply ignore any things
|
|
* which are slightly inconvenient (such as locking conflicts between
|
|
* the page lock and the glock) and return having done no I/O. Its
|
|
* obviously not something we'd want to do on too regular a basis.
|
|
* Any I/O we ignore at this time will be done via readpage later.
|
|
* 2. We don't handle stuffed files here we let readpage do the honours.
|
|
* 3. mpage_readpages() does most of the heavy lifting in the common case.
|
|
* 4. gfs2_block_map() is relied upon to set BH_Boundary in the right places.
|
|
*/
|
|
|
|
static int gfs2_readpages(struct file *file, struct address_space *mapping,
|
|
struct list_head *pages, unsigned nr_pages)
|
|
{
|
|
struct inode *inode = mapping->host;
|
|
struct gfs2_inode *ip = GFS2_I(inode);
|
|
struct gfs2_sbd *sdp = GFS2_SB(inode);
|
|
struct gfs2_holder gh;
|
|
int ret;
|
|
|
|
gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh);
|
|
ret = gfs2_glock_nq(&gh);
|
|
if (unlikely(ret))
|
|
goto out_uninit;
|
|
if (!gfs2_is_stuffed(ip))
|
|
ret = mpage_readpages(mapping, pages, nr_pages, gfs2_block_map);
|
|
gfs2_glock_dq(&gh);
|
|
out_uninit:
|
|
gfs2_holder_uninit(&gh);
|
|
if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
|
|
ret = -EIO;
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* gfs2_write_begin - Begin to write to a file
|
|
* @file: The file to write to
|
|
* @mapping: The mapping in which to write
|
|
* @pos: The file offset at which to start writing
|
|
* @len: Length of the write
|
|
* @flags: Various flags
|
|
* @pagep: Pointer to return the page
|
|
* @fsdata: Pointer to return fs data (unused by GFS2)
|
|
*
|
|
* Returns: errno
|
|
*/
|
|
|
|
static int gfs2_write_begin(struct file *file, struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned flags,
|
|
struct page **pagep, void **fsdata)
|
|
{
|
|
struct gfs2_inode *ip = GFS2_I(mapping->host);
|
|
struct gfs2_sbd *sdp = GFS2_SB(mapping->host);
|
|
struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
|
|
unsigned int data_blocks = 0, ind_blocks = 0, rblocks;
|
|
unsigned requested = 0;
|
|
int alloc_required;
|
|
int error = 0;
|
|
pgoff_t index = pos >> PAGE_CACHE_SHIFT;
|
|
unsigned from = pos & (PAGE_CACHE_SIZE - 1);
|
|
struct page *page;
|
|
|
|
gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &ip->i_gh);
|
|
error = gfs2_glock_nq(&ip->i_gh);
|
|
if (unlikely(error))
|
|
goto out_uninit;
|
|
if (&ip->i_inode == sdp->sd_rindex) {
|
|
error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE,
|
|
GL_NOCACHE, &m_ip->i_gh);
|
|
if (unlikely(error)) {
|
|
gfs2_glock_dq(&ip->i_gh);
|
|
goto out_uninit;
|
|
}
|
|
}
|
|
|
|
alloc_required = gfs2_write_alloc_required(ip, pos, len);
|
|
|
|
if (alloc_required || gfs2_is_jdata(ip))
|
|
gfs2_write_calc_reserv(ip, len, &data_blocks, &ind_blocks);
|
|
|
|
if (alloc_required) {
|
|
struct gfs2_alloc_parms ap = { .aflags = 0, };
|
|
error = gfs2_quota_lock_check(ip);
|
|
if (error)
|
|
goto out_unlock;
|
|
|
|
requested = data_blocks + ind_blocks;
|
|
ap.target = requested;
|
|
error = gfs2_inplace_reserve(ip, &ap);
|
|
if (error)
|
|
goto out_qunlock;
|
|
}
|
|
|
|
rblocks = RES_DINODE + ind_blocks;
|
|
if (gfs2_is_jdata(ip))
|
|
rblocks += data_blocks ? data_blocks : 1;
|
|
if (ind_blocks || data_blocks)
|
|
rblocks += RES_STATFS + RES_QUOTA;
|
|
if (&ip->i_inode == sdp->sd_rindex)
|
|
rblocks += 2 * RES_STATFS;
|
|
if (alloc_required)
|
|
rblocks += gfs2_rg_blocks(ip, requested);
|
|
|
|
error = gfs2_trans_begin(sdp, rblocks,
|
|
PAGE_CACHE_SIZE/sdp->sd_sb.sb_bsize);
|
|
if (error)
|
|
goto out_trans_fail;
|
|
|
|
error = -ENOMEM;
|
|
flags |= AOP_FLAG_NOFS;
|
|
page = grab_cache_page_write_begin(mapping, index, flags);
|
|
*pagep = page;
|
|
if (unlikely(!page))
|
|
goto out_endtrans;
|
|
|
|
if (gfs2_is_stuffed(ip)) {
|
|
error = 0;
|
|
if (pos + len > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) {
|
|
error = gfs2_unstuff_dinode(ip, page);
|
|
if (error == 0)
|
|
goto prepare_write;
|
|
} else if (!PageUptodate(page)) {
|
|
error = stuffed_readpage(ip, page);
|
|
}
|
|
goto out;
|
|
}
|
|
|
|
prepare_write:
|
|
error = __block_write_begin(page, from, len, gfs2_block_map);
|
|
out:
|
|
if (error == 0)
|
|
return 0;
|
|
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
|
|
gfs2_trans_end(sdp);
|
|
if (pos + len > ip->i_inode.i_size)
|
|
gfs2_trim_blocks(&ip->i_inode);
|
|
goto out_trans_fail;
|
|
|
|
out_endtrans:
|
|
gfs2_trans_end(sdp);
|
|
out_trans_fail:
|
|
if (alloc_required) {
|
|
gfs2_inplace_release(ip);
|
|
out_qunlock:
|
|
gfs2_quota_unlock(ip);
|
|
}
|
|
out_unlock:
|
|
if (&ip->i_inode == sdp->sd_rindex) {
|
|
gfs2_glock_dq(&m_ip->i_gh);
|
|
gfs2_holder_uninit(&m_ip->i_gh);
|
|
}
|
|
gfs2_glock_dq(&ip->i_gh);
|
|
out_uninit:
|
|
gfs2_holder_uninit(&ip->i_gh);
|
|
return error;
|
|
}
|
|
|
|
/**
|
|
* adjust_fs_space - Adjusts the free space available due to gfs2_grow
|
|
* @inode: the rindex inode
|
|
*/
|
|
static void adjust_fs_space(struct inode *inode)
|
|
{
|
|
struct gfs2_sbd *sdp = inode->i_sb->s_fs_info;
|
|
struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
|
|
struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
|
|
struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
|
|
struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
|
|
struct buffer_head *m_bh, *l_bh;
|
|
u64 fs_total, new_free;
|
|
|
|
/* Total up the file system space, according to the latest rindex. */
|
|
fs_total = gfs2_ri_total(sdp);
|
|
if (gfs2_meta_inode_buffer(m_ip, &m_bh) != 0)
|
|
return;
|
|
|
|
spin_lock(&sdp->sd_statfs_spin);
|
|
gfs2_statfs_change_in(m_sc, m_bh->b_data +
|
|
sizeof(struct gfs2_dinode));
|
|
if (fs_total > (m_sc->sc_total + l_sc->sc_total))
|
|
new_free = fs_total - (m_sc->sc_total + l_sc->sc_total);
|
|
else
|
|
new_free = 0;
|
|
spin_unlock(&sdp->sd_statfs_spin);
|
|
fs_warn(sdp, "File system extended by %llu blocks.\n",
|
|
(unsigned long long)new_free);
|
|
gfs2_statfs_change(sdp, new_free, new_free, 0);
|
|
|
|
if (gfs2_meta_inode_buffer(l_ip, &l_bh) != 0)
|
|
goto out;
|
|
update_statfs(sdp, m_bh, l_bh);
|
|
brelse(l_bh);
|
|
out:
|
|
brelse(m_bh);
|
|
}
|
|
|
|
/**
|
|
* gfs2_stuffed_write_end - Write end for stuffed files
|
|
* @inode: The inode
|
|
* @dibh: The buffer_head containing the on-disk inode
|
|
* @pos: The file position
|
|
* @len: The length of the write
|
|
* @copied: How much was actually copied by the VFS
|
|
* @page: The page
|
|
*
|
|
* This copies the data from the page into the inode block after
|
|
* the inode data structure itself.
|
|
*
|
|
* Returns: errno
|
|
*/
|
|
static int gfs2_stuffed_write_end(struct inode *inode, struct buffer_head *dibh,
|
|
loff_t pos, unsigned len, unsigned copied,
|
|
struct page *page)
|
|
{
|
|
struct gfs2_inode *ip = GFS2_I(inode);
|
|
struct gfs2_sbd *sdp = GFS2_SB(inode);
|
|
struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
|
|
u64 to = pos + copied;
|
|
void *kaddr;
|
|
unsigned char *buf = dibh->b_data + sizeof(struct gfs2_dinode);
|
|
|
|
BUG_ON((pos + len) > (dibh->b_size - sizeof(struct gfs2_dinode)));
|
|
kaddr = kmap_atomic(page);
|
|
memcpy(buf + pos, kaddr + pos, copied);
|
|
memset(kaddr + pos + copied, 0, len - copied);
|
|
flush_dcache_page(page);
|
|
kunmap_atomic(kaddr);
|
|
|
|
if (!PageUptodate(page))
|
|
SetPageUptodate(page);
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
|
|
if (copied) {
|
|
if (inode->i_size < to)
|
|
i_size_write(inode, to);
|
|
mark_inode_dirty(inode);
|
|
}
|
|
|
|
if (inode == sdp->sd_rindex) {
|
|
adjust_fs_space(inode);
|
|
sdp->sd_rindex_uptodate = 0;
|
|
}
|
|
|
|
brelse(dibh);
|
|
gfs2_trans_end(sdp);
|
|
if (inode == sdp->sd_rindex) {
|
|
gfs2_glock_dq(&m_ip->i_gh);
|
|
gfs2_holder_uninit(&m_ip->i_gh);
|
|
}
|
|
gfs2_glock_dq(&ip->i_gh);
|
|
gfs2_holder_uninit(&ip->i_gh);
|
|
return copied;
|
|
}
|
|
|
|
/**
|
|
* gfs2_write_end
|
|
* @file: The file to write to
|
|
* @mapping: The address space to write to
|
|
* @pos: The file position
|
|
* @len: The length of the data
|
|
* @copied:
|
|
* @page: The page that has been written
|
|
* @fsdata: The fsdata (unused in GFS2)
|
|
*
|
|
* The main write_end function for GFS2. We have a separate one for
|
|
* stuffed files as they are slightly different, otherwise we just
|
|
* put our locking around the VFS provided functions.
|
|
*
|
|
* Returns: errno
|
|
*/
|
|
|
|
static int gfs2_write_end(struct file *file, struct address_space *mapping,
|
|
loff_t pos, unsigned len, unsigned copied,
|
|
struct page *page, void *fsdata)
|
|
{
|
|
struct inode *inode = page->mapping->host;
|
|
struct gfs2_inode *ip = GFS2_I(inode);
|
|
struct gfs2_sbd *sdp = GFS2_SB(inode);
|
|
struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
|
|
struct buffer_head *dibh;
|
|
unsigned int from = pos & (PAGE_CACHE_SIZE - 1);
|
|
unsigned int to = from + len;
|
|
int ret;
|
|
struct gfs2_trans *tr = current->journal_info;
|
|
BUG_ON(!tr);
|
|
|
|
BUG_ON(gfs2_glock_is_locked_by_me(ip->i_gl) == NULL);
|
|
|
|
ret = gfs2_meta_inode_buffer(ip, &dibh);
|
|
if (unlikely(ret)) {
|
|
unlock_page(page);
|
|
page_cache_release(page);
|
|
goto failed;
|
|
}
|
|
|
|
if (gfs2_is_stuffed(ip))
|
|
return gfs2_stuffed_write_end(inode, dibh, pos, len, copied, page);
|
|
|
|
if (!gfs2_is_writeback(ip))
|
|
gfs2_page_add_databufs(ip, page, from, to);
|
|
|
|
ret = generic_write_end(file, mapping, pos, len, copied, page, fsdata);
|
|
if (tr->tr_num_buf_new)
|
|
__mark_inode_dirty(inode, I_DIRTY_DATASYNC);
|
|
else
|
|
gfs2_trans_add_meta(ip->i_gl, dibh);
|
|
|
|
|
|
if (inode == sdp->sd_rindex) {
|
|
adjust_fs_space(inode);
|
|
sdp->sd_rindex_uptodate = 0;
|
|
}
|
|
|
|
brelse(dibh);
|
|
failed:
|
|
gfs2_trans_end(sdp);
|
|
gfs2_inplace_release(ip);
|
|
if (ip->i_res->rs_qa_qd_num)
|
|
gfs2_quota_unlock(ip);
|
|
if (inode == sdp->sd_rindex) {
|
|
gfs2_glock_dq(&m_ip->i_gh);
|
|
gfs2_holder_uninit(&m_ip->i_gh);
|
|
}
|
|
gfs2_glock_dq(&ip->i_gh);
|
|
gfs2_holder_uninit(&ip->i_gh);
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* gfs2_set_page_dirty - Page dirtying function
|
|
* @page: The page to dirty
|
|
*
|
|
* Returns: 1 if it dirtyed the page, or 0 otherwise
|
|
*/
|
|
|
|
static int gfs2_set_page_dirty(struct page *page)
|
|
{
|
|
SetPageChecked(page);
|
|
return __set_page_dirty_buffers(page);
|
|
}
|
|
|
|
/**
|
|
* gfs2_bmap - Block map function
|
|
* @mapping: Address space info
|
|
* @lblock: The block to map
|
|
*
|
|
* Returns: The disk address for the block or 0 on hole or error
|
|
*/
|
|
|
|
static sector_t gfs2_bmap(struct address_space *mapping, sector_t lblock)
|
|
{
|
|
struct gfs2_inode *ip = GFS2_I(mapping->host);
|
|
struct gfs2_holder i_gh;
|
|
sector_t dblock = 0;
|
|
int error;
|
|
|
|
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
|
|
if (error)
|
|
return 0;
|
|
|
|
if (!gfs2_is_stuffed(ip))
|
|
dblock = generic_block_bmap(mapping, lblock, gfs2_block_map);
|
|
|
|
gfs2_glock_dq_uninit(&i_gh);
|
|
|
|
return dblock;
|
|
}
|
|
|
|
static void gfs2_discard(struct gfs2_sbd *sdp, struct buffer_head *bh)
|
|
{
|
|
struct gfs2_bufdata *bd;
|
|
|
|
lock_buffer(bh);
|
|
gfs2_log_lock(sdp);
|
|
clear_buffer_dirty(bh);
|
|
bd = bh->b_private;
|
|
if (bd) {
|
|
if (!list_empty(&bd->bd_list) && !buffer_pinned(bh))
|
|
list_del_init(&bd->bd_list);
|
|
else
|
|
gfs2_remove_from_journal(bh, current->journal_info, 0);
|
|
}
|
|
bh->b_bdev = NULL;
|
|
clear_buffer_mapped(bh);
|
|
clear_buffer_req(bh);
|
|
clear_buffer_new(bh);
|
|
gfs2_log_unlock(sdp);
|
|
unlock_buffer(bh);
|
|
}
|
|
|
|
static void gfs2_invalidatepage(struct page *page, unsigned int offset,
|
|
unsigned int length)
|
|
{
|
|
struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host);
|
|
unsigned int stop = offset + length;
|
|
int partial_page = (offset || length < PAGE_CACHE_SIZE);
|
|
struct buffer_head *bh, *head;
|
|
unsigned long pos = 0;
|
|
|
|
BUG_ON(!PageLocked(page));
|
|
if (!partial_page)
|
|
ClearPageChecked(page);
|
|
if (!page_has_buffers(page))
|
|
goto out;
|
|
|
|
bh = head = page_buffers(page);
|
|
do {
|
|
if (pos + bh->b_size > stop)
|
|
return;
|
|
|
|
if (offset <= pos)
|
|
gfs2_discard(sdp, bh);
|
|
pos += bh->b_size;
|
|
bh = bh->b_this_page;
|
|
} while (bh != head);
|
|
out:
|
|
if (!partial_page)
|
|
try_to_release_page(page, 0);
|
|
}
|
|
|
|
/**
|
|
* gfs2_ok_for_dio - check that dio is valid on this file
|
|
* @ip: The inode
|
|
* @rw: READ or WRITE
|
|
* @offset: The offset at which we are reading or writing
|
|
*
|
|
* Returns: 0 (to ignore the i/o request and thus fall back to buffered i/o)
|
|
* 1 (to accept the i/o request)
|
|
*/
|
|
static int gfs2_ok_for_dio(struct gfs2_inode *ip, int rw, loff_t offset)
|
|
{
|
|
/*
|
|
* Should we return an error here? I can't see that O_DIRECT for
|
|
* a stuffed file makes any sense. For now we'll silently fall
|
|
* back to buffered I/O
|
|
*/
|
|
if (gfs2_is_stuffed(ip))
|
|
return 0;
|
|
|
|
if (offset >= i_size_read(&ip->i_inode))
|
|
return 0;
|
|
return 1;
|
|
}
|
|
|
|
|
|
|
|
static ssize_t gfs2_direct_IO(int rw, struct kiocb *iocb,
|
|
const struct iovec *iov, loff_t offset,
|
|
unsigned long nr_segs)
|
|
{
|
|
struct file *file = iocb->ki_filp;
|
|
struct inode *inode = file->f_mapping->host;
|
|
struct address_space *mapping = inode->i_mapping;
|
|
struct gfs2_inode *ip = GFS2_I(inode);
|
|
struct gfs2_holder gh;
|
|
int rv;
|
|
|
|
/*
|
|
* Deferred lock, even if its a write, since we do no allocation
|
|
* on this path. All we need change is atime, and this lock mode
|
|
* ensures that other nodes have flushed their buffered read caches
|
|
* (i.e. their page cache entries for this inode). We do not,
|
|
* unfortunately have the option of only flushing a range like
|
|
* the VFS does.
|
|
*/
|
|
gfs2_holder_init(ip->i_gl, LM_ST_DEFERRED, 0, &gh);
|
|
rv = gfs2_glock_nq(&gh);
|
|
if (rv)
|
|
return rv;
|
|
rv = gfs2_ok_for_dio(ip, rw, offset);
|
|
if (rv != 1)
|
|
goto out; /* dio not valid, fall back to buffered i/o */
|
|
|
|
/*
|
|
* Now since we are holding a deferred (CW) lock at this point, you
|
|
* might be wondering why this is ever needed. There is a case however
|
|
* where we've granted a deferred local lock against a cached exclusive
|
|
* glock. That is ok provided all granted local locks are deferred, but
|
|
* it also means that it is possible to encounter pages which are
|
|
* cached and possibly also mapped. So here we check for that and sort
|
|
* them out ahead of the dio. The glock state machine will take care of
|
|
* everything else.
|
|
*
|
|
* If in fact the cached glock state (gl->gl_state) is deferred (CW) in
|
|
* the first place, mapping->nr_pages will always be zero.
|
|
*/
|
|
if (mapping->nrpages) {
|
|
loff_t lstart = offset & (PAGE_CACHE_SIZE - 1);
|
|
loff_t len = iov_length(iov, nr_segs);
|
|
loff_t end = PAGE_ALIGN(offset + len) - 1;
|
|
|
|
rv = 0;
|
|
if (len == 0)
|
|
goto out;
|
|
if (test_and_clear_bit(GIF_SW_PAGED, &ip->i_flags))
|
|
unmap_shared_mapping_range(ip->i_inode.i_mapping, offset, len);
|
|
rv = filemap_write_and_wait_range(mapping, lstart, end);
|
|
if (rv)
|
|
goto out;
|
|
if (rw == WRITE)
|
|
truncate_inode_pages_range(mapping, lstart, end);
|
|
}
|
|
|
|
rv = __blockdev_direct_IO(rw, iocb, inode, inode->i_sb->s_bdev, iov,
|
|
offset, nr_segs, gfs2_get_block_direct,
|
|
NULL, NULL, 0);
|
|
out:
|
|
gfs2_glock_dq(&gh);
|
|
gfs2_holder_uninit(&gh);
|
|
return rv;
|
|
}
|
|
|
|
/**
|
|
* gfs2_releasepage - free the metadata associated with a page
|
|
* @page: the page that's being released
|
|
* @gfp_mask: passed from Linux VFS, ignored by us
|
|
*
|
|
* Call try_to_free_buffers() if the buffers in this page can be
|
|
* released.
|
|
*
|
|
* Returns: 0
|
|
*/
|
|
|
|
int gfs2_releasepage(struct page *page, gfp_t gfp_mask)
|
|
{
|
|
struct address_space *mapping = page->mapping;
|
|
struct gfs2_sbd *sdp = gfs2_mapping2sbd(mapping);
|
|
struct buffer_head *bh, *head;
|
|
struct gfs2_bufdata *bd;
|
|
|
|
if (!page_has_buffers(page))
|
|
return 0;
|
|
|
|
gfs2_log_lock(sdp);
|
|
spin_lock(&sdp->sd_ail_lock);
|
|
head = bh = page_buffers(page);
|
|
do {
|
|
if (atomic_read(&bh->b_count))
|
|
goto cannot_release;
|
|
bd = bh->b_private;
|
|
if (bd && bd->bd_tr)
|
|
goto cannot_release;
|
|
if (buffer_pinned(bh) || buffer_dirty(bh))
|
|
goto not_possible;
|
|
bh = bh->b_this_page;
|
|
} while(bh != head);
|
|
spin_unlock(&sdp->sd_ail_lock);
|
|
|
|
head = bh = page_buffers(page);
|
|
do {
|
|
bd = bh->b_private;
|
|
if (bd) {
|
|
gfs2_assert_warn(sdp, bd->bd_bh == bh);
|
|
if (!list_empty(&bd->bd_list))
|
|
list_del_init(&bd->bd_list);
|
|
bd->bd_bh = NULL;
|
|
bh->b_private = NULL;
|
|
kmem_cache_free(gfs2_bufdata_cachep, bd);
|
|
}
|
|
|
|
bh = bh->b_this_page;
|
|
} while (bh != head);
|
|
gfs2_log_unlock(sdp);
|
|
|
|
return try_to_free_buffers(page);
|
|
|
|
not_possible: /* Should never happen */
|
|
WARN_ON(buffer_dirty(bh));
|
|
WARN_ON(buffer_pinned(bh));
|
|
cannot_release:
|
|
spin_unlock(&sdp->sd_ail_lock);
|
|
gfs2_log_unlock(sdp);
|
|
return 0;
|
|
}
|
|
|
|
static const struct address_space_operations gfs2_writeback_aops = {
|
|
.writepage = gfs2_writepage,
|
|
.writepages = gfs2_writepages,
|
|
.readpage = gfs2_readpage,
|
|
.readpages = gfs2_readpages,
|
|
.write_begin = gfs2_write_begin,
|
|
.write_end = gfs2_write_end,
|
|
.bmap = gfs2_bmap,
|
|
.invalidatepage = gfs2_invalidatepage,
|
|
.releasepage = gfs2_releasepage,
|
|
.direct_IO = gfs2_direct_IO,
|
|
.migratepage = buffer_migrate_page,
|
|
.is_partially_uptodate = block_is_partially_uptodate,
|
|
.error_remove_page = generic_error_remove_page,
|
|
};
|
|
|
|
static const struct address_space_operations gfs2_ordered_aops = {
|
|
.writepage = gfs2_writepage,
|
|
.writepages = gfs2_writepages,
|
|
.readpage = gfs2_readpage,
|
|
.readpages = gfs2_readpages,
|
|
.write_begin = gfs2_write_begin,
|
|
.write_end = gfs2_write_end,
|
|
.set_page_dirty = gfs2_set_page_dirty,
|
|
.bmap = gfs2_bmap,
|
|
.invalidatepage = gfs2_invalidatepage,
|
|
.releasepage = gfs2_releasepage,
|
|
.direct_IO = gfs2_direct_IO,
|
|
.migratepage = buffer_migrate_page,
|
|
.is_partially_uptodate = block_is_partially_uptodate,
|
|
.error_remove_page = generic_error_remove_page,
|
|
};
|
|
|
|
static const struct address_space_operations gfs2_jdata_aops = {
|
|
.writepage = gfs2_jdata_writepage,
|
|
.writepages = gfs2_jdata_writepages,
|
|
.readpage = gfs2_readpage,
|
|
.readpages = gfs2_readpages,
|
|
.write_begin = gfs2_write_begin,
|
|
.write_end = gfs2_write_end,
|
|
.set_page_dirty = gfs2_set_page_dirty,
|
|
.bmap = gfs2_bmap,
|
|
.invalidatepage = gfs2_invalidatepage,
|
|
.releasepage = gfs2_releasepage,
|
|
.is_partially_uptodate = block_is_partially_uptodate,
|
|
.error_remove_page = generic_error_remove_page,
|
|
};
|
|
|
|
void gfs2_set_aops(struct inode *inode)
|
|
{
|
|
struct gfs2_inode *ip = GFS2_I(inode);
|
|
|
|
if (gfs2_is_writeback(ip))
|
|
inode->i_mapping->a_ops = &gfs2_writeback_aops;
|
|
else if (gfs2_is_ordered(ip))
|
|
inode->i_mapping->a_ops = &gfs2_ordered_aops;
|
|
else if (gfs2_is_jdata(ip))
|
|
inode->i_mapping->a_ops = &gfs2_jdata_aops;
|
|
else
|
|
BUG();
|
|
}
|
|
|