*/
#include <linux/export.h>
#include <linux/compiler.h>
+#include <linux/dax.h>
#include <linux/fs.h>
#include <linux/uaccess.h>
#include <linux/capability.h>
__radix_tree_lookup(&mapping->page_tree, page->index, &node, &slot);
if (shadow) {
- mapping->nrshadows++;
+ mapping->nrexceptional++;
/*
- * Make sure the nrshadows update is committed before
+ * Make sure the nrexceptional update is committed before
* the nrpages update so that final truncate racing
* with reclaim does not see both counters 0 at the
* same time and miss a shadow entry.
else
cleancache_invalidate_page(mapping, page);
+ VM_BUG_ON_PAGE(page_mapped(page), page);
+ if (!IS_ENABLED(CONFIG_DEBUG_VM) && unlikely(page_mapped(page))) {
+ int mapcount;
+
+ pr_alert("BUG: Bad page cache in process %s pfn:%05lx\n",
+ current->comm, page_to_pfn(page));
+ dump_page(page, "still mapped when deleted");
+ dump_stack();
+ add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE);
+
+ mapcount = page_mapcount(page);
+ if (mapping_exiting(mapping) &&
+ page_count(page) >= mapcount + 2) {
+ /*
+ * All vmas have already been torn down, so it's
+ * a good bet that actually the page is unmapped,
+ * and we'd prefer not to leak it: if we're wrong,
+ * some other bad page check should catch it later.
+ */
+ page_mapcount_reset(page);
+ atomic_sub(mapcount, &page->_count);
+ }
+ }
+
page_cache_tree_delete(mapping, page, shadow);
page->mapping = NULL;
__dec_zone_page_state(page, NR_FILE_PAGES);
if (PageSwapBacked(page))
__dec_zone_page_state(page, NR_SHMEM);
- VM_BUG_ON_PAGE(page_mapped(page), page);
/*
* At this point page must be either written or cleaned by truncate.
{
int err = 0;
- if (mapping->nrpages) {
+ if ((!dax_mapping(mapping) && mapping->nrpages) ||
+ (dax_mapping(mapping) && mapping->nrexceptional)) {
err = filemap_fdatawrite(mapping);
/*
* Even if the above returned error, the pages may be
{
int err = 0;
- if (mapping->nrpages) {
+ if ((!dax_mapping(mapping) && mapping->nrpages) ||
+ (dax_mapping(mapping) && mapping->nrexceptional)) {
err = __filemap_fdatawrite_range(mapping, lstart, lend,
WB_SYNC_ALL);
/* See comment of filemap_write_and_wait() */
p = radix_tree_deref_slot_protected(slot, &mapping->tree_lock);
if (!radix_tree_exceptional_entry(p))
return -EEXIST;
+
+ if (WARN_ON(dax_mapping(mapping)))
+ return -EINVAL;
+
if (shadowp)
*shadowp = p;
- mapping->nrshadows--;
+ mapping->nrexceptional--;
if (node)
workingset_node_shadows_dec(node);
}
if (radix_tree_deref_retry(page))
goto restart;
/*
- * A shadow entry of a recently evicted page,
- * or a swap entry from shmem/tmpfs. Return
- * it without attempting to raise page count.
+ * A shadow entry of a recently evicted page, a swap
+ * entry from shmem/tmpfs or a DAX entry. Return it
+ * without attempting to raise page count.
*/
goto export;
}
}
EXPORT_SYMBOL(find_get_pages_tag);
+/**
+ * find_get_entries_tag - find and return entries that match @tag
+ * @mapping: the address_space to search
+ * @start: the starting page cache index
+ * @tag: the tag index
+ * @nr_entries: the maximum number of entries
+ * @entries: where the resulting entries are placed
+ * @indices: the cache indices corresponding to the entries in @entries
+ *
+ * Like find_get_entries, except we only return entries which are tagged with
+ * @tag.
+ */
+unsigned find_get_entries_tag(struct address_space *mapping, pgoff_t start,
+ int tag, unsigned int nr_entries,
+ struct page **entries, pgoff_t *indices)
+{
+ void **slot;
+ unsigned int ret = 0;
+ struct radix_tree_iter iter;
+
+ if (!nr_entries)
+ return 0;
+
+ rcu_read_lock();
+restart:
+ radix_tree_for_each_tagged(slot, &mapping->page_tree,
+ &iter, start, tag) {
+ struct page *page;
+repeat:
+ page = radix_tree_deref_slot(slot);
+ if (unlikely(!page))
+ continue;
+ if (radix_tree_exception(page)) {
+ if (radix_tree_deref_retry(page)) {
+ /*
+ * Transient condition which can only trigger
+ * when entry at index 0 moves out of or back
+ * to root: none yet gotten, safe to restart.
+ */
+ goto restart;
+ }
+
+ /*
+ * A shadow entry of a recently evicted page, a swap
+ * entry from shmem/tmpfs or a DAX entry. Return it
+ * without attempting to raise page count.
+ */
+ goto export;
+ }
+ if (!page_cache_get_speculative(page))
+ goto repeat;
+
+ /* Has the page moved? */
+ if (unlikely(page != *slot)) {
+ page_cache_release(page);
+ goto repeat;
+ }
+export:
+ indices[ret] = iter.index;
+ entries[ret] = page;
+ if (++ret == nr_entries)
+ break;
+ }
+ rcu_read_unlock();
+ return ret;
+}
+EXPORT_SYMBOL(find_get_entries_tag);
+
/*
* CD/DVDs are error prone. When a medium error occurs, the driver may fail
* a _large_ part of the i/o request. Imagine the worst scenario:
* page_cache_read - adds requested page to the page cache if not already there
* @file: file to read
* @offset: page index
+ * @gfp_mask: memory allocation flags
*
* This adds the requested page to the page cache if it isn't already there,
* and schedules an I/O to read in its contents from disk.
struct inode *inode = file->f_mapping->host;
ssize_t ret;
- mutex_lock(&inode->i_mutex);
+ inode_lock(inode);
ret = generic_write_checks(iocb, from);
if (ret > 0)
ret = __generic_file_write_iter(iocb, from);
- mutex_unlock(&inode->i_mutex);
+ inode_unlock(inode);
if (ret > 0) {
ssize_t err;
projects / deliverable / linux.git / blobdiff