/**
* nilfs_readpages() - implement readpages() method of nilfs_aops {}
* address_space_operations.
* @file - file struct of the file to be read
* @mapping - address_space struct used for reading multiple pages
* @pages - the pages to be read
* @nr_pages - number of pages to be read
*/
static int nilfs_readpages(struct file *file, struct address_space *mapping,
struct list_head *pages, unsigned nr_pages)
{
return mpage_readpages(mapping, pages, nr_pages, nilfs_get_block);
}
static int nilfs_writepages(struct address_space *mapping,
struct writeback_control *wbc)
{
struct inode *inode = mapping->host;
int err = 0;
#if NEED_WB_SYNC_NONE_CHECK_FOR_DO_SYNC_MAPPING_RANGE
if (wbc->sync_mode == WB_SYNC_ALL ||
(wbc->sync_mode == WB_SYNC_NONE && !current_is_pdflush()))
#else
if (wbc->sync_mode == WB_SYNC_ALL)
#endif
err = nilfs_construct_dsync_segment(inode->i_sb, inode,
wbc->range_start,
wbc->range_end);
return err;
}
static int nilfs_writepage(struct page *page, struct writeback_control *wbc)
{
struct inode *inode = page->mapping->host;
int err;
page_debug(3, "called (page=%p, index=%lu, wbc nonblocking %d, "
"wbc for_reclaim %d)\n",
page, page->index, wbc->nonblocking, wbc->for_reclaim);
redirty_page_for_writepage(wbc, page);
unlock_page(page);
if (wbc->sync_mode == WB_SYNC_ALL) {
err = nilfs_construct_segment(inode->i_sb);
if (unlikely(err))
return err;
} else if (wbc->for_reclaim)
nilfs_flush_segment(inode->i_sb, inode->i_ino);
return 0;
}
static int nilfs_set_page_dirty(struct page *page)
{
int ret = __set_page_dirty_buffers(page);
page_debug(3, "called (page=%p)\n", page);
if (ret) {
struct inode *inode = page->mapping->host;
struct nilfs_sb_info *sbi = NILFS_SB(inode->i_sb);
unsigned nr_dirty = 1 << (PAGE_SHIFT - inode->i_blkbits);
nilfs_set_file_dirty(sbi, inode, nr_dirty);
}
page_debug(3, "done (ret=%d, page=%p)\n", ret, page);
return ret;
}
#if HAVE_WRITE_BEGIN_WRITE_END
static int nilfs_write_begin(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len, unsigned flags,
struct page **pagep, void **fsdata)
{
struct inode *inode = mapping->host;
int err = nilfs_transaction_begin(inode->i_sb, NULL, 1);
if (unlikely(err))
return err;
*pagep = NULL;
err = block_write_begin(file, mapping, pos, len, flags, pagep,
fsdata, nilfs_get_block);
if (unlikely(err))
nilfs_transaction_abort(inode->i_sb);
return err;
}
static int nilfs_write_end(struct file *file, struct address_space *mapping,
loff_t pos, unsigned len, unsigned copied,
struct page *page, void *fsdata)
{
struct inode *inode = mapping->host;
unsigned start = pos & (PAGE_CACHE_SIZE - 1);
unsigned nr_dirty;
int err;
nr_dirty = nilfs_page_count_clean_buffers(page, start,
start + copied);
copied = generic_write_end(file, mapping, pos, len, copied, page,
fsdata);
nilfs_set_file_dirty(NILFS_SB(inode->i_sb), inode, nr_dirty);
err = nilfs_transaction_commit(inode->i_sb);
return err ? : copied;
}
#else /* HAVE_WRITE_BEGIN_WRITE_END */
static int nilfs_prepare_write(struct file *file, struct page *page,
unsigned from, unsigned to)
{
struct address_space *mapping = page->mapping;
pgoff_t offset = page->index;
struct inode *inode = mapping->host;
int err;
unlock_page(page);
err = nilfs_transaction_begin(inode->i_sb, NULL, 1);
lock_page(page);
if (unlikely(page->mapping != mapping || page->index != offset)) {
unlock_page(page);
if (likely(!err))
nilfs_transaction_abort(inode->i_sb);
return AOP_TRUNCATED_PAGE;
}
if (unlikely(err))
return err;
err = block_prepare_write(page, from, to, nilfs_get_block);
if (unlikely(err))
nilfs_transaction_abort(inode->i_sb);
return err;
}
/*
* This is called from ocfs2_write_zero_page() which has handled it's
* own cluster locking and has ensured allocation exists for those
* blocks to be written.
*/
int ocfs2_prepare_write_nolock(struct inode *inode, struct page *page,
unsigned from, unsigned to)
{
int ret;
ret = block_prepare_write(page, from, to, ocfs2_get_block);
return ret;
}
/*
* This is called from ocfs2_write_zero_page() which has handled it's
* own cluster locking and has ensured allocation exists for those
* blocks to be written.
*/
int ocfs2_prepare_write_nolock(struct inode *inode, struct page *page,
unsigned from, unsigned to)
{
int ret;
down_read(&OCFS2_I(inode)->ip_alloc_sem);
ret = block_prepare_write(page, from, to, ocfs2_get_block);
up_read(&OCFS2_I(inode)->ip_alloc_sem);
return ret;
}
/*
* Try to make the page cache and handle ready for the inline data case.
* We can call this function in 2 cases:
* 1. The inode is created and the first write exceeds inline size. We can
* clear the inode state safely.
* 2. The inode has inline data, then we need to read the data, make it
* update and dirty so that ext4_da_writepages can handle it. We don't
* need to start the journal since the file's metatdata isn't changed now.
*/
static int ext4_da_convert_inline_data_to_extent(struct address_space *mapping,
struct inode *inode,
unsigned flags,
void **fsdata)
{
int ret = 0, inline_size;
struct page *page;
page = grab_cache_page_write_begin(mapping, 0, flags);
if (!page)
return -ENOMEM;
down_read(&EXT4_I(inode)->xattr_sem);
if (!ext4_has_inline_data(inode)) {
ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
goto out;
}
inline_size = ext4_get_inline_size(inode);
if (!PageUptodate(page)) {
ret = ext4_read_inline_page(inode, page);
if (ret < 0)
goto out;
}
ret = block_prepare_write(page, 0, inline_size,
ext4_da_get_block_prep);
if (ret) {
ext4_truncate_failed_write(inode);
goto out;
}
SetPageDirty(page);
SetPageUptodate(page);
ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
*fsdata = (void *)CONVERT_INLINE_DATA;
out:
up_read(&EXT4_I(inode)->xattr_sem);
if (page) {
unlock_page(page);
page_cache_release(page);
}
return ret;
}
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);
unsigned int data_blocks, ind_blocks, rblocks;
int alloc_required;
int error = 0;
struct gfs2_alloc *al;
pgoff_t index = pos >> PAGE_CACHE_SHIFT;
unsigned from = pos & (PAGE_CACHE_SIZE - 1);
unsigned to = from + len;
struct page *page;
gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_ATIME, &ip->i_gh);
error = gfs2_glock_nq_atime(&ip->i_gh);
if (unlikely(error))
goto out_uninit;
gfs2_write_calc_reserv(ip, len, &data_blocks, &ind_blocks);
error = gfs2_write_alloc_required(ip, pos, len, &alloc_required);
if (error)
goto out_unlock;
if (alloc_required) {
al = gfs2_alloc_get(ip);
if (!al) {
error = -ENOMEM;
goto out_unlock;
}
error = gfs2_quota_lock_check(ip);
if (error)
goto out_alloc_put;
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,
PAGE_CACHE_SIZE/sdp->sd_sb.sb_bsize);
if (error)
goto out_trans_fail;
error = -ENOMEM;
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_prepare_write(page, from, to, gfs2_block_map);
out:
if (error == 0)
return 0;
page_cache_release(page);
if (pos + len > ip->i_inode.i_size)
vmtruncate(&ip->i_inode, ip->i_inode.i_size);
out_endtrans:
gfs2_trans_end(sdp);
out_trans_fail:
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(&ip->i_gh);
out_uninit:
gfs2_holder_uninit(&ip->i_gh);
return error;
}
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;
unsigned int write_len = to - from;
gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_ATIME|LM_FLAG_TRY_1CB, &ip->i_gh);
error = gfs2_glock_nq_atime(&ip->i_gh);
if (unlikely(error)) {
if (error == GLR_TRYFAILED) {
unlock_page(page);
error = AOP_TRUNCATED_PAGE;
yield();
}
goto out_uninit;
}
gfs2_write_calc_reserv(ip, write_len, &data_blocks, &ind_blocks);
error = gfs2_write_alloc_required(ip, pos, write_len, &alloc_required);
if (error)
goto out_unlock;
ip->i_alloc.al_requested = 0;
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_inode.i_uid, ip->i_inode.i_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;
}
static int blkdev_prepare_write(struct file *file, struct page *page, unsigned from, unsigned to)
{
return block_prepare_write(page, from, to, blkdev_get_block);
}
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;
int alloc_required;
int error = 0;
struct gfs2_alloc *al;
pgoff_t index = pos >> PAGE_CACHE_SHIFT;
unsigned from = pos & (PAGE_CACHE_SIZE - 1);
unsigned to = from + len;
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;
}
}
error = gfs2_write_alloc_required(ip, pos, len, &alloc_required);
if (error)
goto out_unlock;
if (alloc_required || gfs2_is_jdata(ip))
gfs2_write_calc_reserv(ip, len, &data_blocks, &ind_blocks);
if (alloc_required) {
al = gfs2_alloc_get(ip);
if (!al) {
error = -ENOMEM;
goto out_unlock;
}
error = gfs2_quota_lock_check(ip);
if (error)
goto out_alloc_put;
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;
if (&ip->i_inode == sdp->sd_rindex)
rblocks += 2 * RES_STATFS;
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_prepare_write(page, from, to, gfs2_block_map);
out:
if (error == 0)
return 0;
page_cache_release(page);
/*
* XXX(hch): the call below should probably be replaced with
* a call to the gfs2-specific truncate blocks helper to actually
* release disk blocks..
*/
if (pos + len > ip->i_inode.i_size)
simple_setsize(&ip->i_inode, ip->i_inode.i_size);
out_endtrans:
gfs2_trans_end(sdp);
out_trans_fail:
if (alloc_required) {
gfs2_inplace_release(ip);
out_qunlock:
gfs2_quota_unlock(ip);
out_alloc_put:
gfs2_alloc_put(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;
}
static int ext4_convert_inline_data_to_extent(struct address_space *mapping,
struct inode *inode,
unsigned flags)
{
int ret, needed_blocks;
handle_t *handle = NULL;
int retries = 0, sem_held = 0;
struct page *page = NULL;
unsigned from, to;
struct ext4_iloc iloc;
if (!ext4_has_inline_data(inode)) {
/*
* clear the flag so that no new write
* will trap here again.
*/
ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
return 0;
}
needed_blocks = ext4_writepage_trans_blocks(inode);
ret = ext4_get_inode_loc(inode, &iloc);
if (ret)
return ret;
retry:
handle = ext4_journal_start(inode, needed_blocks);
if (IS_ERR(handle)) {
ret = PTR_ERR(handle);
handle = NULL;
goto out;
}
/* We cannot recurse into the filesystem as the transaction is already
* started */
flags |= AOP_FLAG_NOFS;
page = grab_cache_page_write_begin(mapping, 0, flags);
if (!page) {
ret = -ENOMEM;
goto out;
}
down_write(&EXT4_I(inode)->xattr_sem);
sem_held = 1;
/* If some one has already done this for us, just exit. */
if (!ext4_has_inline_data(inode)) {
ret = 0;
goto out;
}
from = 0;
to = ext4_get_inline_size(inode);
if (!PageUptodate(page)) {
ret = ext4_read_inline_page(inode, page);
if (ret < 0)
goto out;
}
ret = ext4_destroy_inline_data_nolock(handle, inode);
if (ret)
goto out;
ret = block_prepare_write(page, from & (PAGE_CACHE_SIZE - 1), to, ext4_get_block);
if (!ret && ext4_should_journal_data(inode)) {
ret = walk_page_buffers(handle, page_buffers(page),
from, to, NULL, do_journal_get_write_access);
}
if (ret) {
unlock_page(page);
page_cache_release(page);
ext4_orphan_add(handle, inode);
up_write(&EXT4_I(inode)->xattr_sem);
sem_held = 0;
ext4_journal_stop(handle);
handle = NULL;
ext4_truncate_failed_write(inode);
/*
* If truncate failed early the inode might
* still be on the orphan list; we need to
* make sure the inode is removed from the
* orphan list in that case.
*/
if (inode->i_nlink)
ext4_orphan_del(NULL, inode);
}
if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
goto retry;
block_commit_write(page, from, to);
out:
if (page) {
unlock_page(page);
page_cache_release(page);
}
if (sem_held)
up_write(&EXT4_I(inode)->xattr_sem);
if (handle)
ext4_journal_stop(handle);
brelse(iloc.bh);
return ret;
}
int
ux_prepare_write(struct file *file, struct page *page,
unsigned from, unsigned to)
{
return block_prepare_write(page, from, to, ux_get_block);
}