static void cifs_fscache_inode_now_uncached(void *cookie_netfs_data)
{
struct cifsInodeInfo *cifsi = cookie_netfs_data;
struct pagevec pvec;
pgoff_t first;
int loop, nr_pages;
pagevec_init(&pvec, 0);
first = 0;
cFYI(1, "cifs inode 0x%p now uncached", cifsi);
for (;;) {
nr_pages = pagevec_lookup(&pvec,
cifsi->vfs_inode.i_mapping, first,
PAGEVEC_SIZE - pagevec_count(&pvec));
if (!nr_pages)
break;
for (loop = 0; loop < nr_pages; loop++)
ClearPageFsCache(pvec.pages[loop]);
first = pvec.pages[nr_pages - 1]->index + 1;
pvec.nr = nr_pages;
pagevec_release(&pvec);
cond_resched();
}
}
/**
* nilfs_copy_back_pages -- copy back pages to original cache from shadow cache
* @dmap: destination page cache
* @smap: source page cache
*
* No pages must no be added to the cache during this process.
* This must be ensured by the caller.
*/
void nilfs_copy_back_pages(struct address_space *dmap,
struct address_space *smap)
{
struct pagevec pvec;
unsigned int i, n;
pgoff_t index = 0;
int err;
pagevec_init(&pvec);
repeat:
n = pagevec_lookup(&pvec, smap, &index);
if (!n)
return;
for (i = 0; i < pagevec_count(&pvec); i++) {
struct page *page = pvec.pages[i], *dpage;
pgoff_t offset = page->index;
lock_page(page);
dpage = find_lock_page(dmap, offset);
if (dpage) {
/* override existing page on the destination cache */
WARN_ON(PageDirty(dpage));
nilfs_copy_page(dpage, page, 0);
unlock_page(dpage);
put_page(dpage);
} else {
struct page *page2;
/* move the page to the destination cache */
spin_lock_irq(&smap->tree_lock);
page2 = radix_tree_delete(&smap->page_tree, offset);
WARN_ON(page2 != page);
smap->nrpages--;
spin_unlock_irq(&smap->tree_lock);
spin_lock_irq(&dmap->tree_lock);
err = radix_tree_insert(&dmap->page_tree, offset, page);
if (unlikely(err < 0)) {
WARN_ON(err == -EEXIST);
page->mapping = NULL;
put_page(page); /* for cache */
} else {
page->mapping = dmap;
dmap->nrpages++;
if (PageDirty(page))
radix_tree_tag_set(&dmap->page_tree,
offset,
PAGECACHE_TAG_DIRTY);
}
spin_unlock_irq(&dmap->tree_lock);
}
unlock_page(page);
}
pagevec_release(&pvec);
cond_resched();
goto repeat;
}
/**
* invalidate_inode_pages2 - remove all unmapped pages from an address_space
* @mapping - the address_space
*
* invalidate_inode_pages2() is like truncate_inode_pages(), except for the case
* where the page is seen to be mapped into process pagetables. In that case,
* the page is marked clean but is left attached to its address_space.
*
* The page is also marked not uptodate so that a subsequent pagefault will
* perform I/O to bringthe page's contents back into sync with its backing
* store.
*
* FIXME: invalidate_inode_pages2() is probably trivially livelockable.
*/
void invalidate_inode_pages2(struct address_space *mapping)
{
struct pagevec pvec;
pgoff_t next = 0;
int i;
pagevec_init(&pvec, 0);
while (pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) {
for (i = 0; i < pagevec_count(&pvec); i++) {
struct page *page = pvec.pages[i];
lock_page(page);
if (page->mapping == mapping) { /* truncate race? */
wait_on_page_writeback(page);
next = page->index + 1;
if (page_mapped(page)) {
clear_page_dirty(page);
ClearPageUptodate(page);
} else {
if (!invalidate_complete_page(mapping,
page)) {
clear_page_dirty(page);
ClearPageUptodate(page);
}
}
}
unlock_page(page);
}
pagevec_release(&pvec);
cond_resched();
}
}
///////////////////////////////////////////////////////////
// trace_pages
//
//
///////////////////////////////////////////////////////////
unsigned
trace_pages(
IN struct address_space* mapping
)
{
struct pagevec pvec;
pgoff_t next = 0;
unsigned Ret = 0;
int i;
pagevec_init( &pvec, 0 );
while ( pagevec_lookup( &pvec, mapping, next, PAGEVEC_SIZE ) ) {
for ( i = 0; i < pvec.nr; i++ ) {
struct page *page = pvec.pages[i];
void* d = kmap_atomic( page, KM_USER0 );
DebugTrace( 0, UFSD_LEVEL_VFS, ("p=%p o=%llx f=%lx%s\n", page, (UINT64)page->index << PAGE_CACHE_SHIFT, page->flags, IsZero( d, PAGE_CACHE_SIZE )?", zero" : "" ));
TracePageBuffers( page, 0 );
kunmap_atomic( d, KM_USER0 );
if ( page->index > next )
next = page->index;
Ret += 1;
next += 1;
}
pagevec_release(&pvec);
}
if ( 0 == next )
DebugTrace( 0, UFSD_LEVEL_VFS, ("no pages\n"));
return Ret;
}
/*
* indication the cookie is no longer uncached
* - this function is called when the backing store currently caching a cookie
* is removed
* - the netfs should use this to clean up any markers indicating cached pages
* - this is mandatory for any object that may have data
*/
static void afs_vnode_cache_now_uncached(void *cookie_netfs_data)
{
struct afs_vnode *vnode = cookie_netfs_data;
struct pagevec pvec;
pgoff_t first;
int loop, nr_pages;
_enter("{%x,%x,%Lx}",
vnode->fid.vnode, vnode->fid.unique, vnode->status.data_version);
pagevec_init(&pvec, 0);
first = 0;
for (;;) {
/* grab a bunch of pages to clean */
nr_pages = pagevec_lookup(&pvec, vnode->vfs_inode.i_mapping,
first,
PAGEVEC_SIZE - pagevec_count(&pvec));
if (!nr_pages)
break;
for (loop = 0; loop < nr_pages; loop++)
ClearPageFsCache(pvec.pages[loop]);
first = pvec.pages[nr_pages - 1]->index + 1;
pvec.nr = nr_pages;
pagevec_release(&pvec);
cond_resched();
}
_leave("");
}
/*
* Indication from FS-Cache that the cookie is no longer cached
* - This function is called when the backing store currently caching a cookie
* is removed
* - The netfs should use this to clean up any markers indicating cached pages
* - This is mandatory for any object that may have data
*/
static void nfs_fscache_inode_now_uncached(void *cookie_netfs_data)
{
struct nfs_inode *nfsi = cookie_netfs_data;
struct pagevec pvec;
pgoff_t first;
int loop, nr_pages;
pagevec_init(&pvec, 0);
first = 0;
dprintk("NFS: nfs_inode_now_uncached: nfs_inode 0x%p\n", nfsi);
for (;;) {
/* grab a bunch of pages to unmark */
nr_pages = pagevec_lookup(&pvec,
nfsi->vfs_inode.i_mapping,
first,
PAGEVEC_SIZE - pagevec_count(&pvec));
if (!nr_pages)
break;
for (loop = 0; loop < nr_pages; loop++)
ClearPageFsCache(pvec.pages[loop]);
first = pvec.pages[nr_pages - 1]->index + 1;
pvec.nr = nr_pages;
pagevec_release(&pvec);
cond_resched();
}
}
static void v9fs_cache_inode_now_uncached(void *cookie_netfs_data)
{
struct v9fs_inode *v9inode = cookie_netfs_data;
struct pagevec pvec;
pgoff_t first;
int loop, nr_pages;
pagevec_init(&pvec, 0);
first = 0;
for (;;) {
nr_pages = pagevec_lookup(&pvec, v9inode->vfs_inode.i_mapping,
first,
PAGEVEC_SIZE - pagevec_count(&pvec));
if (!nr_pages)
break;
for (loop = 0; loop < nr_pages; loop++)
ClearPageFsCache(pvec.pages[loop]);
first = pvec.pages[nr_pages - 1]->index + 1;
pvec.nr = nr_pages;
pagevec_release(&pvec);
cond_resched();
}
}
/**
* invalidate_mapping_pages - Invalidate all the unlocked pages of one inode
* @mapping: the address_space which holds the pages to invalidate
* @start: the offset 'from' which to invalidate
* @end: the offset 'to' which to invalidate (inclusive)
*
* This function only removes the unlocked pages, if you want to
* remove all the pages of one inode, you must call truncate_inode_pages.
*
* invalidate_mapping_pages() will not block on IO activity. It will not
* invalidate pages which are dirty, locked, under writeback or mapped into
* pagetables.
*/
unsigned long invalidate_mapping_pages(struct address_space *mapping,
pgoff_t start, pgoff_t end)
{
struct pagevec pvec;
pgoff_t index = start;
unsigned long ret;
unsigned long count = 0;
int i;
/*
* Note: this function may get called on a shmem/tmpfs mapping:
* pagevec_lookup() might then return 0 prematurely (because it
* got a gangful of swap entries); but it's hardly worth worrying
* about - it can rarely have anything to free from such a mapping
* (most pages are dirty), and already skips over any difficulties.
*/
pagevec_init(&pvec, 0);
while (index <= end && pagevec_lookup(&pvec, mapping, index,
min(end - index, (pgoff_t)PAGEVEC_SIZE - 1) + 1)) {
mem_cgroup_uncharge_start();
for (i = 0; i < pagevec_count(&pvec); i++) {
struct page *page = pvec.pages[i];
/* We rely upon deletion not changing page->index */
index = page->index;
if (index > end)
break;
if (!trylock_page(page))
continue;
WARN_ON(page->index != index);
ret = invalidate_inode_page(page);
unlock_page(page);
/*
* Invalidation is a hint that the page is no longer
* of interest and try to speed up its reclaim.
*/
if (!ret)
deactivate_page(page);
count += ret;
}
pagevec_release(&pvec);
mem_cgroup_uncharge_end();
cond_resched();
index++;
}
return count;
}
/*
* Radix-tree checker
*/
void nilfs_check_radix_tree(const char *fname, int line,
struct address_space *mapping, int tag)
{
struct pagevec pvec;
unsigned int i, n;
pgoff_t index = 0;
char *page_type;
int nr_found = 0;
if (tag == PAGECACHE_TAG_DIRTY)
page_type = "dirty";
else if (tag == PAGECACHE_TAG_WRITEBACK)
page_type = "writeback";
else
page_type = "leaking";
pagevec_init(&pvec, 0);
repeat:
if (tag < 0) {
n = pagevec_lookup(&pvec, mapping, index, PAGEVEC_SIZE);
if (n)
index = pvec.pages[n - 1]->index + 1;
} else
n = pagevec_lookup_tag(&pvec, mapping, &index, tag,
PAGEVEC_SIZE);
if (!n) {
if (nr_found)
printk(KERN_WARNING "%s: found %d %s pages\n",
fname, nr_found, page_type);
return;
}
for (i = 0; i < n; i++) {
nilfs_page_debug(fname, line, pvec.pages[i], "%s page",
page_type);
nr_found++;
}
pagevec_release(&pvec);
cond_resched();
goto repeat;
}
/**
* invalidate_mapping_pages - Invalidate all the unlocked pages of one inode
* @mapping: the address_space which holds the pages to invalidate
* @start: the offset 'from' which to invalidate
* @end: the offset 'to' which to invalidate (inclusive)
*
* This function only removes the unlocked pages, if you want to
* remove all the pages of one inode, you must call truncate_inode_pages.
*
* invalidate_mapping_pages() will not block on IO activity. It will not
* invalidate pages which are dirty, locked, under writeback or mapped into
* pagetables.
*/
unsigned long invalidate_mapping_pages(struct address_space *mapping,
pgoff_t start, pgoff_t end)
{
struct pagevec pvec;
pgoff_t next = start;
unsigned long ret = 0;
int i;
pagevec_init(&pvec, 0);
while (next <= end &&
pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) {
for (i = 0; i < pagevec_count(&pvec); i++) {
struct page *page = pvec.pages[i];
if (TestSetPageLocked(page)) {
next++;
continue;
}
if (page->index > next)
next = page->index;
next++;
if (PageDirty(page) || PageWriteback(page))
goto unlock;
if (page_mapped(page))
goto unlock;
ret += invalidate_complete_page(mapping, page);
unlock:
unlock_page(page);
if (next > end)
break;
}
pagevec_release(&pvec);
cond_resched();
}
return ret;
}
/**
* truncate_inode_pages - truncate *all* the pages from an offset
* @mapping: mapping to truncate
* @lstart: offset from which to truncate
*
* Truncate the page cache at a set offset, removing the pages that are beyond
* that offset (and zeroing out partial pages).
*
* Truncate takes two passes - the first pass is nonblocking. It will not
* block on page locks and it will not block on writeback. The second pass
* will wait. This is to prevent as much IO as possible in the affected region.
* The first pass will remove most pages, so the search cost of the second pass
* is low.
*
* When looking at page->index outside the page lock we need to be careful to
* copy it into a local to avoid races (it could change at any time).
*
* We pass down the cache-hot hint to the page freeing code. Even if the
* mapping is large, it is probably the case that the final pages are the most
* recently touched, and freeing happens in ascending file offset order.
*
* Called under (and serialised by) inode->i_sem.
*/
void truncate_inode_pages(struct address_space *mapping, loff_t lstart)
{
const pgoff_t start = (lstart + PAGE_CACHE_SIZE-1) >> PAGE_CACHE_SHIFT;
const unsigned partial = lstart & (PAGE_CACHE_SIZE - 1);
struct pagevec pvec;
pgoff_t next;
int i;
if (mapping->nrpages == 0)
return;
pagevec_init(&pvec, 0);
next = start;
while (pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) {
for (i = 0; i < pagevec_count(&pvec); i++) {
struct page *page = pvec.pages[i];
pgoff_t page_index = page->index;
if (page_index > next)
next = page_index;
next++;
if (TestSetPageLocked(page))
continue;
if (PageWriteback(page)) {
unlock_page(page);
continue;
}
truncate_complete_page(mapping, page);
unlock_page(page);
}
pagevec_release(&pvec);
cond_resched();
}
if (partial) {
struct page *page = find_lock_page(mapping, start - 1);
if (page) {
wait_on_page_writeback(page);
truncate_partial_page(page, partial);
unlock_page(page);
page_cache_release(page);
}
}
next = start;
for ( ; ; ) {
cond_resched();
if (!pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) {
if (next == start)
break;
next = start;
continue;
}
for (i = 0; i < pagevec_count(&pvec); i++) {
struct page *page = pvec.pages[i];
lock_page(page);
wait_on_page_writeback(page);
if (page->index > next)
next = page->index;
next++;
truncate_complete_page(mapping, page);
unlock_page(page);
}
pagevec_release(&pvec);
}
}
/**
* invalidate_inode_pages2_range - remove range of pages from an address_space
* @mapping: the address_space
* @start: the page offset 'from' which to invalidate
* @end: the page offset 'to' which to invalidate (inclusive)
*
* Any pages which are found to be mapped into pagetables are unmapped prior to
* invalidation.
*
* Returns -EBUSY if any pages could not be invalidated.
*/
int invalidate_inode_pages2_range(struct address_space *mapping,
pgoff_t start, pgoff_t end)
{
struct pagevec pvec;
pgoff_t index;
int i;
int ret = 0;
int ret2 = 0;
int did_range_unmap = 0;
cleancache_invalidate_inode(mapping);
pagevec_init(&pvec, 0);
index = start;
while (index <= end && pagevec_lookup(&pvec, mapping, index,
min(end - index, (pgoff_t)PAGEVEC_SIZE - 1) + 1)) {
mem_cgroup_uncharge_start();
for (i = 0; i < pagevec_count(&pvec); i++) {
struct page *page = pvec.pages[i];
/* We rely upon deletion not changing page->index */
index = page->index;
if (index > end)
break;
lock_page(page);
WARN_ON(page->index != index);
if (page->mapping != mapping) {
unlock_page(page);
continue;
}
wait_on_page_writeback(page);
if (page_mapped(page)) {
if (!did_range_unmap) {
/*
* Zap the rest of the file in one hit.
*/
unmap_mapping_range(mapping,
(loff_t)index << PAGE_CACHE_SHIFT,
(loff_t)(1 + end - index)
<< PAGE_CACHE_SHIFT,
0);
did_range_unmap = 1;
} else {
/*
* Just zap this page
*/
unmap_mapping_range(mapping,
(loff_t)index << PAGE_CACHE_SHIFT,
PAGE_CACHE_SIZE, 0);
}
}
BUG_ON(page_mapped(page));
ret2 = do_launder_page(mapping, page);
if (ret2 == 0) {
if (!invalidate_complete_page2(mapping, page))
ret2 = -EBUSY;
}
if (ret2 < 0)
ret = ret2;
unlock_page(page);
}
pagevec_release(&pvec);
mem_cgroup_uncharge_end();
cond_resched();
index++;
}
cleancache_invalidate_inode(mapping);
return ret;
}
/**
* truncate_inode_pages_range - truncate range of pages specified by start & end byte offsets
* @mapping: mapping to truncate
* @lstart: offset from which to truncate
* @lend: offset to which to truncate (inclusive)
*
* Truncate the page cache, removing the pages that are between
* specified offsets (and zeroing out partial pages
* if lstart or lend + 1 is not page aligned).
*
* Truncate takes two passes - the first pass is nonblocking. It will not
* block on page locks and it will not block on writeback. The second pass
* will wait. This is to prevent as much IO as possible in the affected region.
* The first pass will remove most pages, so the search cost of the second pass
* is low.
*
* We pass down the cache-hot hint to the page freeing code. Even if the
* mapping is large, it is probably the case that the final pages are the most
* recently touched, and freeing happens in ascending file offset order.
*
* Note that since ->invalidatepage() accepts range to invalidate
* truncate_inode_pages_range is able to handle cases where lend + 1 is not
* page aligned properly.
*/
void truncate_inode_pages_range(struct address_space *mapping,
loff_t lstart, loff_t lend)
{
pgoff_t start; /* inclusive */
pgoff_t end; /* exclusive */
unsigned int partial_start; /* inclusive */
unsigned int partial_end; /* exclusive */
struct pagevec pvec;
pgoff_t index;
int i;
cleancache_invalidate_inode(mapping);
if (mapping->nrpages == 0)
return;
/* Offsets within partial pages */
partial_start = lstart & (PAGE_CACHE_SIZE - 1);
partial_end = (lend + 1) & (PAGE_CACHE_SIZE - 1);
/*
* 'start' and 'end' always covers the range of pages to be fully
* truncated. Partial pages are covered with 'partial_start' at the
* start of the range and 'partial_end' at the end of the range.
* Note that 'end' is exclusive while 'lend' is inclusive.
*/
start = (lstart + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
if (lend == -1)
/*
* lend == -1 indicates end-of-file so we have to set 'end'
* to the highest possible pgoff_t and since the type is
* unsigned we're using -1.
*/
end = -1;
else
end = (lend + 1) >> PAGE_CACHE_SHIFT;
pagevec_init(&pvec, 0);
index = start;
while (index < end && pagevec_lookup(&pvec, mapping, index,
min(end - index, (pgoff_t)PAGEVEC_SIZE))) {
mem_cgroup_uncharge_start();
for (i = 0; i < pagevec_count(&pvec); i++) {
struct page *page = pvec.pages[i];
/* We rely upon deletion not changing page->index */
index = page->index;
if (index >= end)
break;
if (!trylock_page(page))
continue;
WARN_ON(page->index != index);
if (PageWriteback(page)) {
unlock_page(page);
continue;
}
truncate_inode_page(mapping, page);
unlock_page(page);
}
pagevec_release(&pvec);
mem_cgroup_uncharge_end();
cond_resched();
index++;
}
if (partial_start) {
struct page *page = find_lock_page(mapping, start - 1);
if (page) {
unsigned int top = PAGE_CACHE_SIZE;
if (start > end) {
/* Truncation within a single page */
top = partial_end;
partial_end = 0;
}
wait_on_page_writeback(page);
zero_user_segment(page, partial_start, top);
cleancache_invalidate_page(mapping, page);
if (page_has_private(page))
do_invalidatepage(page, partial_start,
top - partial_start);
unlock_page(page);
page_cache_release(page);
}
}
if (partial_end) {
struct page *page = find_lock_page(mapping, end);
if (page) {
wait_on_page_writeback(page);
zero_user_segment(page, 0, partial_end);
cleancache_invalidate_page(mapping, page);
if (page_has_private(page))
do_invalidatepage(page, 0,
partial_end);
unlock_page(page);
page_cache_release(page);
}
}
/*
* If the truncation happened within a single page no pages
* will be released, just zeroed, so we can bail out now.
*/
if (start >= end)
return;
index = start;
for ( ; ; ) {
cond_resched();
if (!pagevec_lookup(&pvec, mapping, index,
min(end - index, (pgoff_t)PAGEVEC_SIZE))) {
if (index == start)
break;
index = start;
continue;
}
if (index == start && pvec.pages[0]->index >= end) {
pagevec_release(&pvec);
break;
}
mem_cgroup_uncharge_start();
for (i = 0; i < pagevec_count(&pvec); i++) {
struct page *page = pvec.pages[i];
/* We rely upon deletion not changing page->index */
index = page->index;
if (index >= end)
break;
lock_page(page);
WARN_ON(page->index != index);
wait_on_page_writeback(page);
truncate_inode_page(mapping, page);
unlock_page(page);
}
pagevec_release(&pvec);
mem_cgroup_uncharge_end();
index++;
}
cleancache_invalidate_inode(mapping);
}
/*
* This routine is called to find out and return a data or hole offset
* from the page cache for unwritten extents according to the desired
* type for xfs_seek_data() or xfs_seek_hole().
*
* The argument offset is used to tell where we start to search from the
* page cache. Map is used to figure out the end points of the range to
* lookup pages.
*
* Return true if the desired type of offset was found, and the argument
* offset is filled with that address. Otherwise, return false and keep
* offset unchanged.
*/
STATIC bool
xfs_find_get_desired_pgoff(
struct inode *inode,
struct xfs_bmbt_irec *map,
unsigned int type,
loff_t *offset)
{
struct xfs_inode *ip = XFS_I(inode);
struct xfs_mount *mp = ip->i_mount;
struct pagevec pvec;
pgoff_t index;
pgoff_t end;
loff_t endoff;
loff_t startoff = *offset;
loff_t lastoff = startoff;
bool found = false;
pagevec_init(&pvec, 0);
index = startoff >> PAGE_CACHE_SHIFT;
endoff = XFS_FSB_TO_B(mp, map->br_startoff + map->br_blockcount);
end = endoff >> PAGE_CACHE_SHIFT;
do {
int want;
unsigned nr_pages;
unsigned int i;
want = min_t(pgoff_t, end - index, PAGEVEC_SIZE);
nr_pages = pagevec_lookup(&pvec, inode->i_mapping, index,
want);
/*
* No page mapped into given range. If we are searching holes
* and if this is the first time we got into the loop, it means
* that the given offset is landed in a hole, return it.
*
* If we have already stepped through some block buffers to find
* holes but they all contains data. In this case, the last
* offset is already updated and pointed to the end of the last
* mapped page, if it does not reach the endpoint to search,
* that means there should be a hole between them.
*/
if (nr_pages == 0) {
/* Data search found nothing */
if (type == DATA_OFF)
break;
ASSERT(type == HOLE_OFF);
if (lastoff == startoff || lastoff < endoff) {
found = true;
*offset = lastoff;
}
break;
}
/*
* At lease we found one page. If this is the first time we
* step into the loop, and if the first page index offset is
* greater than the given search offset, a hole was found.
*/
if (type == HOLE_OFF && lastoff == startoff &&
lastoff < page_offset(pvec.pages[0])) {
found = true;
break;
}
for (i = 0; i < nr_pages; i++) {
struct page *page = pvec.pages[i];
loff_t b_offset;
/*
* At this point, the page may be truncated or
* invalidated (changing page->mapping to NULL),
* or even swizzled back from swapper_space to tmpfs
* file mapping. However, page->index will not change
* because we have a reference on the page.
*
* Searching done if the page index is out of range.
* If the current offset is not reaches the end of
* the specified search range, there should be a hole
* between them.
*/
if (page->index > end) {
if (type == HOLE_OFF && lastoff < endoff) {
*offset = lastoff;
found = true;
}
goto out;
}
lock_page(page);
/*
* Page truncated or invalidated(page->mapping == NULL).
* We can freely skip it and proceed to check the next
* page.
*/
if (unlikely(page->mapping != inode->i_mapping)) {
unlock_page(page);
continue;
}
if (!page_has_buffers(page)) {
unlock_page(page);
continue;
}
found = xfs_lookup_buffer_offset(page, &b_offset, type);
if (found) {
/*
* The found offset may be less than the start
* point to search if this is the first time to
* come here.
*/
*offset = max_t(loff_t, startoff, b_offset);
unlock_page(page);
goto out;
}
/*
* We either searching data but nothing was found, or
* searching hole but found a data buffer. In either
* case, probably the next page contains the desired
* things, update the last offset to it so.
*/
lastoff = page_offset(page) + PAGE_SIZE;
unlock_page(page);
}
/*
* The number of returned pages less than our desired, search
* done. In this case, nothing was found for searching data,
* but we found a hole behind the last offset.
*/
if (nr_pages < want) {
if (type == HOLE_OFF) {
*offset = lastoff;
found = true;
}
break;
}
index = pvec.pages[i - 1]->index + 1;
pagevec_release(&pvec);
} while (index <= end);
out:
pagevec_release(&pvec);
return found;
}
