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 error;
int done_trans = 0;
error = gfs2_writepage_common(page, wbc);
if (error <= 0)
return error;
if (PageChecked(page)) {
if (wbc->sync_mode != WB_SYNC_ALL)
goto out_ignore;
error = gfs2_trans_begin(sdp, RES_DINODE + 1, 0);
if (error)
goto out_ignore;
done_trans = 1;
}
error = __gfs2_jdata_writepage(page, wbc);
if (done_trans)
gfs2_trans_end(sdp);
return error;
out_ignore:
redirty_page_for_writepage(wbc, page);
unlock_page(page);
return 0;
}
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);
goto out;
}
return 1;
redirty:
redirty_page_for_writepage(wbc, page);
out:
unlock_page(page);
return 0;
}
static int gfs2_aspace_writepage(struct page *page, struct writeback_control *wbc)
{
int err;
struct buffer_head *bh, *head;
int nr_underway = 0;
int write_op = (1 << BIO_RW_META) | ((wbc->sync_mode == WB_SYNC_ALL ?
WRITE_SYNC_PLUG : WRITE));
BUG_ON(!PageLocked(page));
BUG_ON(!page_has_buffers(page));
head = page_buffers(page);
bh = head;
do {
if (!buffer_mapped(bh))
continue;
/*
* If it's a fully non-blocking write attempt and we cannot
* lock the buffer then redirty the page. Note that this can
* potentially cause a busy-wait loop from pdflush and kswapd
* activity, but those code paths have their own higher-level
* throttling.
*/
if (wbc->sync_mode != WB_SYNC_NONE || !wbc->nonblocking) {
lock_buffer(bh);
} else if (!trylock_buffer(bh)) {
redirty_page_for_writepage(wbc, page);
continue;
}
if (test_clear_buffer_dirty(bh)) {
mark_buffer_async_write(bh);
} else {
unlock_buffer(bh);
}
} while ((bh = bh->b_this_page) != head);
/*
* The page and its buffers are protected by PageWriteback(), so we can
* drop the bh refcounts early.
*/
BUG_ON(PageWriteback(page));
set_page_writeback(page);
do {
struct buffer_head *next = bh->b_this_page;
if (buffer_async_write(bh)) {
submit_bh(write_op, bh);
nr_underway++;
}
bh = next;
} while (bh != head);
unlock_page(page);
err = 0;
if (nr_underway == 0)
end_page_writeback(page);
return err;
}
/**
* ecryptfs_writepage
* @page: Page that is locked before this call is made
*
* Returns zero on success; non-zero otherwise
<<<<<<< HEAD
=======
<<<<<<< HEAD
>>>>>>> ae1773bb70f3d7cf73324ce8fba787e01d8fa9f2
*
* This is where we encrypt the data and pass the encrypted data to
* the lower filesystem. In OpenPGP-compatible mode, we operate on
* entire underlying packets.
<<<<<<< HEAD
=======
=======
>>>>>>> 58a75b6a81be54a8b491263ca1af243e9d8617b9
>>>>>>> ae1773bb70f3d7cf73324ce8fba787e01d8fa9f2
*/
static int ecryptfs_writepage(struct page *page, struct writeback_control *wbc)
{
int rc;
/*
* Refuse to write the page out if we are called from reclaim context
* since our writepage() path may potentially allocate memory when
* calling into the lower fs vfs_write() which may in turn invoke
* us again.
*/
if (current->flags & PF_MEMALLOC) {
redirty_page_for_writepage(wbc, page);
rc = 0;
goto out;
}
rc = ecryptfs_encrypt_page(page);
if (rc) {
ecryptfs_printk(KERN_WARNING, "Error encrypting "
"page (upper index [0x%.16lx])\n", page->index);
ClearPageUptodate(page);
goto out;
}
SetPageUptodate(page);
out:
unlock_page(page);
return rc;
}
static int nilfs_writepage(struct page *page, struct writeback_control *wbc)
{
struct inode *inode = page->mapping->host;
int err;
if (inode->i_sb->s_flags & MS_RDONLY) {
/*
* It means that filesystem was remounted in read-only
* mode because of error or metadata corruption. But we
* have dirty pages that try to be flushed in background.
* So, here we simply discard this dirty page.
*/
nilfs_clear_dirty_page(page, false);
unlock_page(page);
return -EROFS;
}
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;
}
/**
* ecryptfs_writepage
* @page: Page that is locked before this call is made
*
* Returns zero on success; non-zero otherwise
*
* This is where we encrypt the data and pass the encrypted data to
* the lower filesystem. In OpenPGP-compatible mode, we operate on
* entire underlying packets.
*/
static int ecryptfs_writepage(struct page *page, struct writeback_control *wbc)
{
int rc;
#if 1 // FEATURE_SDCARD_ENCRYPTION
struct inode *ecryptfs_inode;
struct ecryptfs_crypt_stat *crypt_stat =
&ecryptfs_inode_to_private(page->mapping->host)->crypt_stat;
ecryptfs_inode = page->mapping->host;
#endif
/*
* Refuse to write the page out if we are called from reclaim context
* since our writepage() path may potentially allocate memory when
* calling into the lower fs vfs_write() which may in turn invoke
* us again.
*/
if (current->flags & PF_MEMALLOC) {
redirty_page_for_writepage(wbc, page);
rc = 0;
goto out;
}
#if 1 // FEATURE_SDCARD_ENCRYPTION
if (!crypt_stat || !(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
ecryptfs_printk(KERN_DEBUG,
"Passing through unencrypted page\n");
rc = ecryptfs_write_lower_page_segment(ecryptfs_inode, page,
0, PAGE_CACHE_SIZE);
if (rc) {
ClearPageUptodate(page);
goto out;
}
SetPageUptodate(page);
} else {
rc = ecryptfs_encrypt_page(page);
if (rc) {
ecryptfs_printk(KERN_WARNING, "Error encrypting "
"page (upper index [0x%.16lx])\n", page->index);
ClearPageUptodate(page);
goto out;
}
SetPageUptodate(page);
}
#else
rc = ecryptfs_encrypt_page(page);
if (rc) {
ecryptfs_printk(KERN_WARNING, "Error encrypting "
"page (upper index [0x%.16lx])\n", page->index);
ClearPageUptodate(page);
goto out;
}
SetPageUptodate(page);
#endif
out:
unlock_page(page);
return rc;
}
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 nilfs_writepage(struct page *page, struct writeback_control *wbc)
{
struct inode *inode = page->mapping->host;
int err;
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_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 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);
int ret;
if (gfs2_assert_withdraw(sdp, gfs2_glock_is_held_excl(ip->i_gl)))
goto out;
if (PageChecked(page) || current->journal_info)
goto out_ignore;
ret = __gfs2_jdata_writepage(page, wbc);
return ret;
out_ignore:
redirty_page_for_writepage(wbc, page);
out:
unlock_page(page);
return 0;
}
static int ecryptfs_writepage(struct page *page, struct writeback_control *wbc)
{
int rc;
if (current->flags & PF_MEMALLOC) {
redirty_page_for_writepage(wbc, page);
rc = 0;
goto out;
}
rc = ecryptfs_encrypt_page(page);
if (rc) {
ecryptfs_printk(KERN_WARNING, "Error encrypting "
"page (upper index [0x%.16lx])\n", page->index);
ClearPageUptodate(page);
goto out;
}
SetPageUptodate(page);
out:
unlock_page(page);
return rc;
}
/*
* Redirty all the pages in a given range.
*/
static void afs_redirty_pages(struct writeback_control *wbc,
struct address_space *mapping,
pgoff_t first, pgoff_t last)
{
struct afs_vnode *vnode = AFS_FS_I(mapping->host);
struct pagevec pv;
unsigned count, loop;
_enter("{%x:%u},%lx-%lx",
vnode->fid.vid, vnode->fid.vnode, first, last);
pagevec_init(&pv);
do {
_debug("redirty %lx-%lx", first, last);
count = last - first + 1;
if (count > PAGEVEC_SIZE)
count = PAGEVEC_SIZE;
pv.nr = find_get_pages_contig(mapping, first, count, pv.pages);
ASSERTCMP(pv.nr, ==, count);
for (loop = 0; loop < count; loop++) {
struct page *page = pv.pages[loop];
redirty_page_for_writepage(wbc, page);
end_page_writeback(page);
if (page->index >= first)
first = page->index + 1;
}
__pagevec_release(&pv);
} while (first <= last);
_leave("");
}
static int f2fs_write_data_page(struct page *page,
struct writeback_control *wbc)
{
struct inode *inode = page->mapping->host;
struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
loff_t i_size = i_size_read(inode);
const pgoff_t end_index = ((unsigned long long) i_size)
>> PAGE_CACHE_SHIFT;
unsigned offset = 0;
bool need_balance_fs = false;
int err = 0;
struct f2fs_io_info fio = {
.sbi = sbi,
.type = DATA,
.rw = (wbc->sync_mode == WB_SYNC_ALL) ? WRITE_SYNC : WRITE,
.page = page,
.encrypted_page = NULL,
};
trace_f2fs_writepage(page, DATA);
if (page->index < end_index)
goto write;
/*
* If the offset is out-of-range of file size,
* this page does not have to be written to disk.
*/
offset = i_size & (PAGE_CACHE_SIZE - 1);
if ((page->index >= end_index + 1) || !offset)
goto out;
zero_user_segment(page, offset, PAGE_CACHE_SIZE);
write:
if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
goto redirty_out;
if (f2fs_is_drop_cache(inode))
goto out;
if (f2fs_is_volatile_file(inode) && !wbc->for_reclaim &&
available_free_memory(sbi, BASE_CHECK))
goto redirty_out;
/* Dentry blocks are controlled by checkpoint */
if (S_ISDIR(inode->i_mode)) {
if (unlikely(f2fs_cp_error(sbi)))
goto redirty_out;
err = do_write_data_page(&fio);
goto done;
}
/* we should bypass data pages to proceed the kworkder jobs */
if (unlikely(f2fs_cp_error(sbi))) {
SetPageError(page);
goto out;
}
if (!wbc->for_reclaim)
need_balance_fs = true;
else if (has_not_enough_free_secs(sbi, 0))
goto redirty_out;
err = -EAGAIN;
f2fs_lock_op(sbi);
if (f2fs_has_inline_data(inode))
err = f2fs_write_inline_data(inode, page);
if (err == -EAGAIN)
err = do_write_data_page(&fio);
f2fs_unlock_op(sbi);
done:
if (err && err != -ENOENT)
goto redirty_out;
clear_cold_data(page);
out:
inode_dec_dirty_pages(inode);
if (err)
ClearPageUptodate(page);
unlock_page(page);
if (need_balance_fs)
f2fs_balance_fs(sbi);
if (wbc->for_reclaim)
f2fs_submit_merged_bio(sbi, DATA, WRITE);
return 0;
redirty_out:
redirty_page_for_writepage(wbc, page);
return AOP_WRITEPAGE_ACTIVATE;
}
static int __f2fs_writepage(struct page *page, struct writeback_control *wbc,
void *data)
{
struct address_space *mapping = data;
int ret = mapping->a_ops->writepage(page, wbc);
mapping_set_error(mapping, ret);
return ret;
}
/*
* This function was copied from write_cche_pages from mm/page-writeback.c.
* The major change is making write step of cold data page separately from
* warm/hot data page.
*/
static int f2fs_write_cache_pages(struct address_space *mapping,
struct writeback_control *wbc, writepage_t writepage,
void *data)
{
int ret = 0;
int done = 0;
struct pagevec pvec;
int nr_pages;
pgoff_t uninitialized_var(writeback_index);
pgoff_t index;
pgoff_t end; /* Inclusive */
pgoff_t done_index;
int cycled;
int range_whole = 0;
int tag;
int step = 0;
pagevec_init(&pvec, 0);
next:
if (wbc->range_cyclic) {
writeback_index = mapping->writeback_index; /* prev offset */
index = writeback_index;
if (index == 0)
cycled = 1;
else
cycled = 0;
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;
cycled = 1; /* ignore range_cyclic tests */
}
if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
tag = PAGECACHE_TAG_TOWRITE;
else
tag = PAGECACHE_TAG_DIRTY;
retry:
if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
tag_pages_for_writeback(mapping, index, end);
done_index = index;
while (!done && (index <= end)) {
int i;
nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, tag,
min(end - index, (pgoff_t)PAGEVEC_SIZE - 1) + 1);
if (nr_pages == 0)
break;
for (i = 0; i < nr_pages; i++) {
struct page *page = pvec.pages[i];
if (page->index > end) {
done = 1;
break;
}
done_index = page->index;
lock_page(page);
if (unlikely(page->mapping != mapping)) {
continue_unlock:
unlock_page(page);
continue;
}
if (!PageDirty(page)) {
/* someone wrote it for us */
goto continue_unlock;
}
if (step == is_cold_data(page))
goto continue_unlock;
if (PageWriteback(page)) {
if (wbc->sync_mode != WB_SYNC_NONE)
f2fs_wait_on_page_writeback(page, DATA);
else
goto continue_unlock;
}
BUG_ON(PageWriteback(page));
if (!clear_page_dirty_for_io(page))
goto continue_unlock;
ret = (*writepage)(page, wbc, data);
if (unlikely(ret)) {
if (ret == AOP_WRITEPAGE_ACTIVATE) {
unlock_page(page);
ret = 0;
} else {
done_index = page->index + 1;
done = 1;
break;
}
}
if (--wbc->nr_to_write <= 0 &&
wbc->sync_mode == WB_SYNC_NONE) {
done = 1;
break;
}
}
pagevec_release(&pvec);
cond_resched();
}
if (step < 1) {
step++;
goto next;
}
if (!cycled && !done) {
cycled = 1;
index = 0;
end = writeback_index - 1;
goto retry;
}
if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
mapping->writeback_index = done_index;
return ret;
}
/**
* ecryptfs_writepage
* @page: Page that is locked before this call is made
*
* Returns zero on success; non-zero otherwise
*
* This is where we encrypt the data and pass the encrypted data to
* the lower filesystem. In OpenPGP-compatible mode, we operate on
* entire underlying packets.
*/
static int ecryptfs_writepage(struct page *page, struct writeback_control *wbc)
{
#ifndef CONFIG_CRYPTO_DEV_KFIPS
int rc;
#else
struct ecryptfs_page_crypt_req *page_crypt_req;
int rc = 0;
#endif
#if 1 // FEATURE_SDCARD_ENCRYPTION
struct inode *ecryptfs_inode;
struct ecryptfs_crypt_stat *crypt_stat =
&ecryptfs_inode_to_private(page->mapping->host)->crypt_stat;
ecryptfs_inode = page->mapping->host;
#endif
/*
* Refuse to write the page out if we are called from reclaim context
* since our writepage() path may potentially allocate memory when
* calling into the lower fs vfs_write() which may in turn invoke
* us again.
*/
if (current->flags & PF_MEMALLOC) {
redirty_page_for_writepage(wbc, page);
#ifndef CONFIG_CRYPTO_DEV_KFIPS
rc = 0;
#endif
goto out;
}
#if 1 // FEATURE_SDCARD_ENCRYPTION
if (!crypt_stat || !(crypt_stat->flags & ECRYPTFS_ENCRYPTED)) {
ecryptfs_printk(KERN_DEBUG,
"Passing through unencrypted page\n");
rc = ecryptfs_write_lower_page_segment(ecryptfs_inode, page,
0, PAGE_CACHE_SIZE);
if (rc) {
ClearPageUptodate(page);
goto out;
}
SetPageUptodate(page);
} else {
#ifndef CONFIG_CRYPTO_DEV_KFIPS
rc = ecryptfs_encrypt_page(page);
if (rc) {
ecryptfs_printk(KERN_WARNING, "Error encrypting "
"page (upper index [0x%.16lx])\n", page->index);
ClearPageUptodate(page);
#else
// rc = ecryptfs_encrypt_page(page);
// if (rc) {
// ecryptfs_printk(KERN_WARNING, "Error encrypting "
// "page (upper index [0x%.16lx])\n", page->index);
// ClearPageUptodate(page);
page_crypt_req = ecryptfs_alloc_page_crypt_req(
page, ecryptfs_writepage_complete);
if (unlikely(!page_crypt_req)) {
rc = -ENOMEM;
ecryptfs_printk(KERN_ERR,
"Failed to allocate page crypt request "
"for encryption\n");
#endif
goto out;
}
#ifndef CONFIG_CRYPTO_DEV_KFIPS
SetPageUptodate(page);
#else
// SetPageUptodate(page);
set_page_writeback(page);
ecryptfs_encrypt_page_async(page_crypt_req);
#endif
}
#else
rc = ecryptfs_encrypt_page(page);
if (rc) {
ecryptfs_printk(KERN_WARNING, "Error encrypting "
"page (upper index [0x%.16lx])\n", page->index);
ClearPageUptodate(page);
goto out;
}
SetPageUptodate(page);
#endif
out:
unlock_page(page);
return rc;
}
static void strip_xattr_flag(char *page_virt,
struct ecryptfs_crypt_stat *crypt_stat)
{
if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) {
size_t written;
crypt_stat->flags &= ~ECRYPTFS_METADATA_IN_XATTR;
ecryptfs_write_crypt_stat_flags(page_virt, crypt_stat,
&written);
crypt_stat->flags |= ECRYPTFS_METADATA_IN_XATTR;
}
}
/**
* Header Extent:
* Octets 0-7: Unencrypted file size (big-endian)
* Octets 8-15: eCryptfs special marker
* Octets 16-19: Flags
* Octet 16: File format version number (between 0 and 255)
* Octets 17-18: Reserved
* Octet 19: Bit 1 (lsb): Reserved
* Bit 2: Encrypted?
* Bits 3-8: Reserved
* Octets 20-23: Header extent size (big-endian)
* Octets 24-25: Number of header extents at front of file
* (big-endian)
* Octet 26: Begin RFC 2440 authentication token packet set
*/
/**
* ecryptfs_copy_up_encrypted_with_header
* @page: Sort of a ``virtual'' representation of the encrypted lower
* file. The actual lower file does not have the metadata in
* the header. This is locked.
* @crypt_stat: The eCryptfs inode's cryptographic context
*
* The ``view'' is the version of the file that userspace winds up
* seeing, with the header information inserted.
*/
static int
ecryptfs_copy_up_encrypted_with_header(struct page *page,
struct ecryptfs_crypt_stat *crypt_stat)
{
loff_t extent_num_in_page = 0;
loff_t num_extents_per_page = (PAGE_CACHE_SIZE
/ crypt_stat->extent_size);
int rc = 0;
while (extent_num_in_page < num_extents_per_page) {
loff_t view_extent_num = ((((loff_t)page->index)
* num_extents_per_page)
+ extent_num_in_page);
size_t num_header_extents_at_front =
(crypt_stat->metadata_size / crypt_stat->extent_size);
if (view_extent_num < num_header_extents_at_front) {
/* This is a header extent */
char *page_virt;
page_virt = kmap_atomic(page);
memset(page_virt, 0, PAGE_CACHE_SIZE);
/* TODO: Support more than one header extent */
if (view_extent_num == 0) {
size_t written;
rc = ecryptfs_read_xattr_region(
page_virt, page->mapping->host);
strip_xattr_flag(page_virt + 16, crypt_stat);
ecryptfs_write_header_metadata(page_virt + 20,
crypt_stat,
&written);
}
kunmap_atomic(page_virt);
flush_dcache_page(page);
if (rc) {
printk(KERN_ERR "%s: Error reading xattr "
"region; rc = [%d]\n", __func__, rc);
goto out;
}
} else {
/* This is an encrypted data extent */
loff_t lower_offset =
((view_extent_num * crypt_stat->extent_size)
- crypt_stat->metadata_size);
rc = ecryptfs_read_lower_page_segment(
page, (lower_offset >> PAGE_CACHE_SHIFT),
(lower_offset & ~PAGE_CACHE_MASK),
crypt_stat->extent_size, page->mapping->host);
if (rc) {
printk(KERN_ERR "%s: Error attempting to read "
"extent at offset [%lld] in the lower "
"file; rc = [%d]\n", __func__,
lower_offset, rc);
goto out;
}
}
extent_num_in_page++;
}
out:
return rc;
}
/**
* ntfs_mft_writepage - check if a metadata page contains dirty mft records
* @page: metadata page possibly containing dirty mft records
* @wbc: writeback control structure
*
* This is called from the VM when it wants to have a dirty $MFT/$DATA metadata
* page cache page cleaned. The VM has already locked the page and marked it
* clean. Instead of writing the page as a conventional ->writepage function
* would do, we check if the page still contains any dirty mft records (it must
* have done at some point in the past since the page was marked dirty) and if
* none are found, i.e. all mft records are clean, we unlock the page and
* return. The VM is then free to do with the page as it pleases. If on the
* other hand we do find any dirty mft records in the page, we redirty the page
* before unlocking it and returning so the VM knows that the page is still
* busy and cannot be thrown out.
*
* Note, we do not actually write any dirty mft records here because they are
* dirty inodes and hence will be written by the VFS inode dirty code paths.
* There is no need to write them from the VM page dirty code paths, too and in
* fact once we implement journalling it would be a complete nightmare having
* two code paths leading to mft record writeout.
*/
static int ntfs_mft_writepage(struct page *page, struct writeback_control *wbc)
{
struct inode *mft_vi = page->mapping->host;
struct super_block *sb = mft_vi->i_sb;
ntfs_volume *vol = NTFS_SB(sb);
u8 *maddr;
MFT_RECORD *m;
ntfs_inode **extent_nis;
unsigned long mft_no;
int nr, i, j;
BOOL is_dirty = FALSE;
BUG_ON(!PageLocked(page));
BUG_ON(PageWriteback(page));
BUG_ON(mft_vi != vol->mft_ino);
/* The first mft record number in the page. */
mft_no = page->index << (PAGE_CACHE_SHIFT - vol->mft_record_size_bits);
/* Number of mft records in the page. */
nr = PAGE_CACHE_SIZE >> vol->mft_record_size_bits;
BUG_ON(!nr);
ntfs_debug("Entering for %i inodes starting at 0x%lx.", nr, mft_no);
/* Iterate over the mft records in the page looking for a dirty one. */
maddr = (u8*)kmap(page);
for (i = 0; i < nr; ++i, ++mft_no, maddr += vol->mft_record_size) {
struct inode *vi;
ntfs_inode *ni, *eni;
ntfs_attr na;
na.mft_no = mft_no;
na.name = NULL;
na.name_len = 0;
na.type = AT_UNUSED;
/*
* Check if the inode corresponding to this mft record is in
* the VFS inode cache and obtain a reference to it if it is.
*/
ntfs_debug("Looking for inode 0x%lx in icache.", mft_no);
/*
* For inode 0, i.e. $MFT itself, we cannot use ilookup5() from
* here or we deadlock because the inode is already locked by
* the kernel (fs/fs-writeback.c::__sync_single_inode()) and
* ilookup5() waits until the inode is unlocked before
* returning it and it never gets unlocked because
* ntfs_mft_writepage() never returns. )-: Fortunately, we
* have inode 0 pinned in icache for the duration of the mount
* so we can access it directly.
*/
if (!mft_no) {
/* Balance the below iput(). */
vi = igrab(mft_vi);
BUG_ON(vi != mft_vi);
} else
vi = ilookup5(sb, mft_no, (test_t)ntfs_test_inode, &na);
if (vi) {
ntfs_debug("Inode 0x%lx is in icache.", mft_no);
/* The inode is in icache. Check if it is dirty. */
ni = NTFS_I(vi);
if (!NInoDirty(ni)) {
/* The inode is not dirty, skip this record. */
ntfs_debug("Inode 0x%lx is not dirty, "
"continuing search.", mft_no);
iput(vi);
continue;
}
ntfs_debug("Inode 0x%lx is dirty, aborting search.",
mft_no);
/* The inode is dirty, no need to search further. */
iput(vi);
is_dirty = TRUE;
break;
}
ntfs_debug("Inode 0x%lx is not in icache.", mft_no);
/* The inode is not in icache. */
/* Skip the record if it is not a mft record (type "FILE"). */
if (!ntfs_is_mft_recordp(maddr)) {
ntfs_debug("Mft record 0x%lx is not a FILE record, "
"continuing search.", mft_no);
continue;
}
m = (MFT_RECORD*)maddr;
/*
* Skip the mft record if it is not in use. FIXME: What about
* deleted/deallocated (extent) inodes? (AIA)
*/
if (!(m->flags & MFT_RECORD_IN_USE)) {
ntfs_debug("Mft record 0x%lx is not in use, "
"continuing search.", mft_no);
continue;
}
/* Skip the mft record if it is a base inode. */
if (!m->base_mft_record) {
ntfs_debug("Mft record 0x%lx is a base record, "
"continuing search.", mft_no);
continue;
}
/*
* This is an extent mft record. Check if the inode
* corresponding to its base mft record is in icache.
*/
na.mft_no = MREF_LE(m->base_mft_record);
ntfs_debug("Mft record 0x%lx is an extent record. Looking "
"for base inode 0x%lx in icache.", mft_no,
na.mft_no);
vi = ilookup5(sb, na.mft_no, (test_t)ntfs_test_inode,
&na);
if (!vi) {
/*
* The base inode is not in icache. Skip this extent
* mft record.
*/
ntfs_debug("Base inode 0x%lx is not in icache, "
"continuing search.", na.mft_no);
continue;
}
ntfs_debug("Base inode 0x%lx is in icache.", na.mft_no);
/*
* The base inode is in icache. Check if it has the extent
* inode corresponding to this extent mft record attached.
*/
ni = NTFS_I(vi);
down(&ni->extent_lock);
if (ni->nr_extents <= 0) {
/*
* The base inode has no attached extent inodes. Skip
* this extent mft record.
*/
up(&ni->extent_lock);
iput(vi);
continue;
}
/* Iterate over the attached extent inodes. */
extent_nis = ni->ext.extent_ntfs_inos;
for (eni = NULL, j = 0; j < ni->nr_extents; ++j) {
if (mft_no == extent_nis[j]->mft_no) {
/*
* Found the extent inode corresponding to this
* extent mft record.
*/
eni = extent_nis[j];
break;
}
}
/*
* If the extent inode was not attached to the base inode, skip
* this extent mft record.
*/
if (!eni) {
up(&ni->extent_lock);
iput(vi);
continue;
}
/*
* Found the extent inode corrsponding to this extent mft
* record. If it is dirty, no need to search further.
*/
if (NInoDirty(eni)) {
up(&ni->extent_lock);
iput(vi);
is_dirty = TRUE;
break;
}
/* The extent inode is not dirty, so do the next record. */
up(&ni->extent_lock);
iput(vi);
}
kunmap(page);
/* If a dirty mft record was found, redirty the page. */
if (is_dirty) {
ntfs_debug("Inode 0x%lx is dirty. Redirtying the page "
"starting at inode 0x%lx.", mft_no,
page->index << (PAGE_CACHE_SHIFT -
vol->mft_record_size_bits));
redirty_page_for_writepage(wbc, page);
unlock_page(page);
} else {
/*
* Keep the VM happy. This must be done otherwise the
* radix-tree tag PAGECACHE_TAG_DIRTY remains set even though
* the page is clean.
*/
BUG_ON(PageWriteback(page));
set_page_writeback(page);
unlock_page(page);
end_page_writeback(page);
}
ntfs_debug("Done.");
return 0;
}
