android_kernel_xiaomi_sm8350/fs/gfs2/ops_address.c
Steven Whitehouse 48516ced21 [GFS2] Remove uneeded endian conversion
In many places GFS2 was calling the endian conversion routines
for an inode even when only a single field, or a few fields might
have changed. As a result we were copying lots of data needlessly.

This patch replaces those calls with conversion of just the
required fields in each case. This should be faster and easier
to understand. There are still other places which suffer from this
problem, but this is a start in the right direction.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2006-10-02 12:39:19 -04:00

791 lines
19 KiB
C

/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2006 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/gfs2_ondisk.h>
#include <linux/lm_interface.h>
#include "gfs2.h"
#include "incore.h"
#include "bmap.h"
#include "glock.h"
#include "inode.h"
#include "log.h"
#include "meta_io.h"
#include "ops_address.h"
#include "quota.h"
#include "trans.h"
#include "rgrp.h"
#include "ops_file.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;
gfs2_trans_add_bh(ip->i_gl, bh, 0);
}
}
/**
* gfs2_get_block - 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
*/
int gfs2_get_block(struct inode *inode, sector_t lblock,
struct buffer_head *bh_result, int create)
{
return gfs2_block_map(inode, lblock, create, bh_result, 32);
}
/**
* 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, 0, bh_result, 1);
if (error)
return error;
if (bh_result->b_blocknr == 0)
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, 0, bh_result, 32);
}
/**
* gfs2_writepage - Write complete page
* @page: Page to write
*
* Returns: errno
*
* Some of this is copied from block_write_full_page() although we still
* call it to do most of the work.
*/
static int gfs2_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);
loff_t i_size = i_size_read(inode);
pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
unsigned offset;
int error;
int done_trans = 0;
if (gfs2_assert_withdraw(sdp, gfs2_glock_is_held_excl(ip->i_gl))) {
unlock_page(page);
return -EIO;
}
if (current->journal_info)
goto out_ignore;
/* 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);
unlock_page(page);
return 0; /* don't care */
}
if (sdp->sd_args.ar_data == GFS2_DATA_ORDERED || gfs2_is_jdata(ip)) {
error = gfs2_trans_begin(sdp, RES_DINODE + 1, 0);
if (error)
goto out_ignore;
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);
done_trans = 1;
}
error = block_write_full_page(page, gfs2_get_block_noalloc, wbc);
if (done_trans)
gfs2_trans_end(sdp);
gfs2_meta_cache_flush(ip);
return error;
out_ignore:
redirty_page_for_writepage(wbc, page);
unlock_page(page);
return 0;
}
static int zero_readpage(struct page *page)
{
void *kaddr;
kaddr = kmap_atomic(page, KM_USER0);
memset(kaddr, 0, PAGE_CACHE_SIZE);
kunmap_atomic(page, KM_USER0);
SetPageUptodate(page);
return 0;
}
/**
* 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;
void *kaddr;
int error;
/* Only the first page of a stuffed file might contain data */
if (unlikely(page->index))
return zero_readpage(page);
error = gfs2_meta_inode_buffer(ip, &dibh);
if (error)
return error;
kaddr = kmap_atomic(page, KM_USER0);
memcpy(kaddr, dibh->b_data + sizeof(struct gfs2_dinode),
ip->i_di.di_size);
memset(kaddr + ip->i_di.di_size, 0, PAGE_CACHE_SIZE - ip->i_di.di_size);
kunmap_atomic(page, KM_USER0);
brelse(dibh);
SetPageUptodate(page);
return 0;
}
/**
* gfs2_readpage - readpage with locking
* @file: The file to read a page for. N.B. This may be NULL if we are
* reading an internal file.
* @page: The page to read
*
* Returns: errno
*/
static int gfs2_readpage(struct file *file, struct page *page)
{
struct gfs2_inode *ip = GFS2_I(page->mapping->host);
struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host);
struct gfs2_file *gf = NULL;
struct gfs2_holder gh;
int error;
int do_unlock = 0;
if (likely(file != &gfs2_internal_file_sentinel)) {
if (file) {
gf = file->private_data;
if (test_bit(GFF_EXLOCK, &gf->f_flags))
/* gfs2_sharewrite_nopage has grabbed the ip->i_gl already */
goto skip_lock;
}
gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME|GL_AOP, &gh);
do_unlock = 1;
error = gfs2_glock_nq_m_atime(1, &gh);
if (unlikely(error))
goto out_unlock;
}
skip_lock:
if (gfs2_is_stuffed(ip)) {
error = stuffed_readpage(ip, page);
unlock_page(page);
} else
error = mpage_readpage(page, gfs2_get_block);
if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
error = -EIO;
if (do_unlock) {
gfs2_glock_dq_m(1, &gh);
gfs2_holder_uninit(&gh);
}
out:
return error;
out_unlock:
unlock_page(page);
if (do_unlock)
gfs2_holder_uninit(&gh);
goto out;
}
/**
* 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 have to handle stuffed files here too.
* 3. mpage_readpages() does most of the heavy lifting in the common case.
* 4. gfs2_get_block() is relied upon to set BH_Boundary in the right places.
* 5. We use LM_FLAG_TRY_1CB here, effectively we then have lock-ahead as
* well as read-ahead.
*/
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;
unsigned page_idx;
int ret;
int do_unlock = 0;
if (likely(file != &gfs2_internal_file_sentinel)) {
if (file) {
struct gfs2_file *gf = file->private_data;
if (test_bit(GFF_EXLOCK, &gf->f_flags))
goto skip_lock;
}
gfs2_holder_init(ip->i_gl, LM_ST_SHARED,
LM_FLAG_TRY_1CB|GL_ATIME|GL_AOP, &gh);
do_unlock = 1;
ret = gfs2_glock_nq_m_atime(1, &gh);
if (ret == GLR_TRYFAILED)
goto out_noerror;
if (unlikely(ret))
goto out_unlock;
}
skip_lock:
if (gfs2_is_stuffed(ip)) {
struct pagevec lru_pvec;
pagevec_init(&lru_pvec, 0);
for (page_idx = 0; page_idx < nr_pages; page_idx++) {
struct page *page = list_entry(pages->prev, struct page, lru);
prefetchw(&page->flags);
list_del(&page->lru);
if (!add_to_page_cache(page, mapping,
page->index, GFP_KERNEL)) {
ret = stuffed_readpage(ip, page);
unlock_page(page);
if (!pagevec_add(&lru_pvec, page))
__pagevec_lru_add(&lru_pvec);
} else {
page_cache_release(page);
}
}
pagevec_lru_add(&lru_pvec);
ret = 0;
} else {
/* What we really want to do .... */
ret = mpage_readpages(mapping, pages, nr_pages, gfs2_get_block);
}
if (do_unlock) {
gfs2_glock_dq_m(1, &gh);
gfs2_holder_uninit(&gh);
}
out:
if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
ret = -EIO;
return ret;
out_noerror:
ret = 0;
out_unlock:
/* unlock all pages, we can't do any I/O right now */
for (page_idx = 0; page_idx < nr_pages; page_idx++) {
struct page *page = list_entry(pages->prev, struct page, lru);
list_del(&page->lru);
unlock_page(page);
page_cache_release(page);
}
if (do_unlock)
gfs2_holder_uninit(&gh);
goto out;
}
/**
* gfs2_prepare_write - Prepare to write a page to a file
* @file: The file to write to
* @page: The page which is to be prepared for writing
* @from: From (byte range within page)
* @to: To (byte range within page)
*
* Returns: errno
*/
static int gfs2_prepare_write(struct file *file, struct page *page,
unsigned from, unsigned to)
{
struct gfs2_inode *ip = GFS2_I(page->mapping->host);
struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host);
unsigned int data_blocks, ind_blocks, rblocks;
int alloc_required;
int error = 0;
loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + from;
loff_t end = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
struct gfs2_alloc *al;
gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_ATIME|GL_AOP, &ip->i_gh);
error = gfs2_glock_nq_m_atime(1, &ip->i_gh);
if (error)
goto out_uninit;
gfs2_write_calc_reserv(ip, to - from, &data_blocks, &ind_blocks);
error = gfs2_write_alloc_required(ip, pos, from - to, &alloc_required);
if (error)
goto out_unlock;
if (alloc_required) {
al = gfs2_alloc_get(ip);
error = gfs2_quota_lock(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
if (error)
goto out_alloc_put;
error = gfs2_quota_check(ip, ip->i_di.di_uid, ip->i_di.di_gid);
if (error)
goto out_qunlock;
al->al_requested = data_blocks + ind_blocks;
error = gfs2_inplace_reserve(ip);
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;
error = gfs2_trans_begin(sdp, rblocks, 0);
if (error)
goto out;
if (gfs2_is_stuffed(ip)) {
if (end > 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_prepare_write(page, from, to, gfs2_get_block);
out:
if (error) {
gfs2_trans_end(sdp);
if (alloc_required) {
gfs2_inplace_release(ip);
out_qunlock:
gfs2_quota_unlock(ip);
out_alloc_put:
gfs2_alloc_put(ip);
}
out_unlock:
gfs2_glock_dq_m(1, &ip->i_gh);
out_uninit:
gfs2_holder_uninit(&ip->i_gh);
}
return error;
}
/**
* gfs2_commit_write - Commit write to a file
* @file: The file to write to
* @page: The page containing the data
* @from: From (byte range within page)
* @to: To (byte range within page)
*
* Returns: errno
*/
static int gfs2_commit_write(struct file *file, struct page *page,
unsigned from, unsigned to)
{
struct inode *inode = page->mapping->host;
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_sbd *sdp = GFS2_SB(inode);
int error = -EOPNOTSUPP;
struct buffer_head *dibh;
struct gfs2_alloc *al = &ip->i_alloc;
struct gfs2_dinode *di;
if (gfs2_assert_withdraw(sdp, gfs2_glock_is_locked_by_me(ip->i_gl)))
goto fail_nounlock;
error = gfs2_meta_inode_buffer(ip, &dibh);
if (error)
goto fail_endtrans;
gfs2_trans_add_bh(ip->i_gl, dibh, 1);
di = (struct gfs2_dinode *)dibh->b_data;
if (gfs2_is_stuffed(ip)) {
u64 file_size;
void *kaddr;
file_size = ((u64)page->index << PAGE_CACHE_SHIFT) + to;
kaddr = kmap_atomic(page, KM_USER0);
memcpy(dibh->b_data + sizeof(struct gfs2_dinode) + from,
kaddr + from, to - from);
kunmap_atomic(page, KM_USER0);
SetPageUptodate(page);
if (inode->i_size < file_size)
i_size_write(inode, file_size);
} else {
if (sdp->sd_args.ar_data == GFS2_DATA_ORDERED ||
gfs2_is_jdata(ip))
gfs2_page_add_databufs(ip, page, from, to);
error = generic_commit_write(file, page, from, to);
if (error)
goto fail;
}
if (ip->i_di.di_size < inode->i_size) {
ip->i_di.di_size = inode->i_size;
di->di_size = cpu_to_be64(inode->i_size);
}
di->di_mode = cpu_to_be32(inode->i_mode);
di->di_atime = cpu_to_be64(inode->i_atime.tv_sec);
di->di_mtime = cpu_to_be64(inode->i_mtime.tv_sec);
di->di_ctime = cpu_to_be64(inode->i_ctime.tv_sec);
brelse(dibh);
gfs2_trans_end(sdp);
if (al->al_requested) {
gfs2_inplace_release(ip);
gfs2_quota_unlock(ip);
gfs2_alloc_put(ip);
}
gfs2_glock_dq_m(1, &ip->i_gh);
gfs2_holder_uninit(&ip->i_gh);
return 0;
fail:
brelse(dibh);
fail_endtrans:
gfs2_trans_end(sdp);
if (al->al_requested) {
gfs2_inplace_release(ip);
gfs2_quota_unlock(ip);
gfs2_alloc_put(ip);
}
gfs2_glock_dq_m(1, &ip->i_gh);
gfs2_holder_uninit(&ip->i_gh);
fail_nounlock:
ClearPageUptodate(page);
return error;
}
/**
* 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_get_block);
gfs2_glock_dq_uninit(&i_gh);
return dblock;
}
static void discard_buffer(struct gfs2_sbd *sdp, struct buffer_head *bh)
{
struct gfs2_bufdata *bd;
gfs2_log_lock(sdp);
bd = bh->b_private;
if (bd) {
bd->bd_bh = NULL;
bh->b_private = NULL;
}
gfs2_log_unlock(sdp);
lock_buffer(bh);
clear_buffer_dirty(bh);
bh->b_bdev = NULL;
clear_buffer_mapped(bh);
clear_buffer_req(bh);
clear_buffer_new(bh);
clear_buffer_delay(bh);
unlock_buffer(bh);
}
static void gfs2_invalidatepage(struct page *page, unsigned long offset)
{
struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host);
struct buffer_head *head, *bh, *next;
unsigned int curr_off = 0;
BUG_ON(!PageLocked(page));
if (!page_has_buffers(page))
return;
bh = head = page_buffers(page);
do {
unsigned int next_off = curr_off + bh->b_size;
next = bh->b_this_page;
if (offset <= curr_off)
discard_buffer(sdp, bh);
curr_off = next_off;
bh = next;
} while (bh != head);
if (!offset)
try_to_release_page(page, 0);
return;
}
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 gfs2_inode *ip = GFS2_I(inode);
struct gfs2_holder gh;
int rv;
if (rw == READ)
mutex_lock(&inode->i_mutex);
/*
* Shared lock, even if its a write, since we do no allocation
* on this path. All we need change is atime.
*/
gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &gh);
rv = gfs2_glock_nq_m_atime(1, &gh);
if (rv)
goto out;
if (offset > i_size_read(inode))
goto out;
/*
* Should we return an error here? I can't see that O_DIRECT for
* a journaled file makes any sense. For now we'll silently fall
* back to buffered I/O, likewise we do the same for stuffed
* files since they are (a) small and (b) unaligned.
*/
if (gfs2_is_jdata(ip))
goto out;
if (gfs2_is_stuffed(ip))
goto out;
rv = blockdev_direct_IO_own_locking(rw, iocb, inode,
inode->i_sb->s_bdev,
iov, offset, nr_segs,
gfs2_get_block_direct, NULL);
out:
gfs2_glock_dq_m(1, &gh);
gfs2_holder_uninit(&gh);
if (rw == READ)
mutex_unlock(&inode->i_mutex);
return rv;
}
/**
* stuck_releasepage - We're stuck in gfs2_releasepage(). Print stuff out.
* @bh: the buffer we're stuck on
*
*/
static void stuck_releasepage(struct buffer_head *bh)
{
struct inode *inode = bh->b_page->mapping->host;
struct gfs2_sbd *sdp = inode->i_sb->s_fs_info;
struct gfs2_bufdata *bd = bh->b_private;
struct gfs2_glock *gl;
static unsigned limit = 0;
if (limit > 3)
return;
limit++;
fs_warn(sdp, "stuck in gfs2_releasepage() %p\n", inode);
fs_warn(sdp, "blkno = %llu, bh->b_count = %d\n",
(unsigned long long)bh->b_blocknr, atomic_read(&bh->b_count));
fs_warn(sdp, "pinned = %u\n", buffer_pinned(bh));
fs_warn(sdp, "bh->b_private = %s\n", (bd) ? "!NULL" : "NULL");
if (!bd)
return;
gl = bd->bd_gl;
fs_warn(sdp, "gl = (%u, %llu)\n",
gl->gl_name.ln_type, (unsigned long long)gl->gl_name.ln_number);
fs_warn(sdp, "bd_list_tr = %s, bd_le.le_list = %s\n",
(list_empty(&bd->bd_list_tr)) ? "no" : "yes",
(list_empty(&bd->bd_le.le_list)) ? "no" : "yes");
if (gl->gl_ops == &gfs2_inode_glops) {
struct gfs2_inode *ip = gl->gl_object;
unsigned int x;
if (!ip)
return;
fs_warn(sdp, "ip = %llu %llu\n",
(unsigned long long)ip->i_num.no_formal_ino,
(unsigned long long)ip->i_num.no_addr);
for (x = 0; x < GFS2_MAX_META_HEIGHT; x++)
fs_warn(sdp, "ip->i_cache[%u] = %s\n",
x, (ip->i_cache[x]) ? "!NULL" : "NULL");
}
}
/**
* 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 inode *aspace = page->mapping->host;
struct gfs2_sbd *sdp = aspace->i_sb->s_fs_info;
struct buffer_head *bh, *head;
struct gfs2_bufdata *bd;
unsigned long t = jiffies + gfs2_tune_get(sdp, gt_stall_secs) * HZ;
if (!page_has_buffers(page))
goto out;
head = bh = page_buffers(page);
do {
while (atomic_read(&bh->b_count)) {
if (!atomic_read(&aspace->i_writecount))
return 0;
if (time_after_eq(jiffies, t)) {
stuck_releasepage(bh);
/* should we withdraw here? */
return 0;
}
yield();
}
gfs2_assert_warn(sdp, !buffer_pinned(bh));
gfs2_assert_warn(sdp, !buffer_dirty(bh));
gfs2_log_lock(sdp);
bd = bh->b_private;
if (bd) {
gfs2_assert_warn(sdp, bd->bd_bh == bh);
gfs2_assert_warn(sdp, list_empty(&bd->bd_list_tr));
gfs2_assert_warn(sdp, !bd->bd_ail);
bd->bd_bh = NULL;
if (!list_empty(&bd->bd_le.le_list))
bd = NULL;
bh->b_private = NULL;
}
gfs2_log_unlock(sdp);
if (bd)
kmem_cache_free(gfs2_bufdata_cachep, bd);
bh = bh->b_this_page;
} while (bh != head);
out:
return try_to_free_buffers(page);
}
const struct address_space_operations gfs2_file_aops = {
.writepage = gfs2_writepage,
.readpage = gfs2_readpage,
.readpages = gfs2_readpages,
.sync_page = block_sync_page,
.prepare_write = gfs2_prepare_write,
.commit_write = gfs2_commit_write,
.bmap = gfs2_bmap,
.invalidatepage = gfs2_invalidatepage,
.releasepage = gfs2_releasepage,
.direct_IO = gfs2_direct_IO,
};