1 files changed, 100 insertions, 34 deletions

diff --git a/fs/afs/write.c b/fs/afs/write.c
index ca4909baf5e6..9ebdd36eaf2f 100644
--- a/fs/afs/write.c
+++ b/fs/afs/write.c
@@ -12,23 +12,37 @@
 #include <linux/writeback.h>
 #include <linux/pagevec.h>
 #include <linux/netfs.h>
-#include <linux/fscache.h>
 #include "internal.h"
 
+static void afs_write_to_cache(struct afs_vnode *vnode, loff_t start, size_t len,
+			       loff_t i_size, bool caching);
+
+#ifdef CONFIG_AFS_FSCACHE
 /*
- * mark a page as having been made dirty and thus needing writeback
+ * Mark a page as having been made dirty and thus needing writeback.  We also
+ * need to pin the cache object to write back to.
  */
-int afs_set_page_dirty(struct page *page)
+bool afs_dirty_folio(struct address_space *mapping, struct folio *folio)
+{
+	return fscache_dirty_folio(mapping, folio,
+				afs_vnode_cache(AFS_FS_I(mapping->host)));
+}
+static void afs_folio_start_fscache(bool caching, struct folio *folio)
+{
+	if (caching)
+		folio_start_fscache(folio);
+}
+#else
+static void afs_folio_start_fscache(bool caching, struct folio *folio)
 {
-	_enter("");
-	return __set_page_dirty_nobuffers(page);
 }
+#endif
 
 /*
  * prepare to perform part of a write to a page
  */
 int afs_write_begin(struct file *file, struct address_space *mapping,
-		    loff_t pos, unsigned len, unsigned flags,
+		    loff_t pos, unsigned len,
 		    struct page **_page, void **fsdata)
 {
 	struct afs_vnode *vnode = AFS_FS_I(file_inode(file));
@@ -46,8 +60,7 @@ int afs_write_begin(struct file *file, struct address_space *mapping,
 	 * file.  We need to do this before we get a lock on the page in case
 	 * there's more than one writer competing for the same cache block.
 	 */
-	ret = netfs_write_begin(file, mapping, pos, len, flags, &folio, fsdata,
-				&afs_req_ops, NULL);
+	ret = netfs_write_begin(&vnode->netfs, file, mapping, pos, len, &folio, fsdata);
 	if (ret < 0)
 		return ret;
 
@@ -78,7 +91,7 @@ try_again:
 			goto flush_conflicting_write;
 	}
 
-	*_page = &folio->page;
+	*_page = folio_file_page(folio, pos / PAGE_SIZE);
 	_leave(" = 0");
 	return 0;
 
@@ -114,7 +127,7 @@ int afs_write_end(struct file *file, struct address_space *mapping,
 	unsigned long priv;
 	unsigned int f, from = offset_in_folio(folio, pos);
 	unsigned int t, to = from + copied;
-	loff_t i_size, maybe_i_size;
+	loff_t i_size, write_end_pos;
 
 	_enter("{%llx:%llu},{%lx}",
 	       vnode->fid.vid, vnode->fid.vnode, folio_index(folio));
@@ -131,15 +144,16 @@ int afs_write_end(struct file *file, struct address_space *mapping,
 	if (copied == 0)
 		goto out;
 
-	maybe_i_size = pos + copied;
+	write_end_pos = pos + copied;
 
-	i_size = i_size_read(&vnode->vfs_inode);
-	if (maybe_i_size > i_size) {
+	i_size = i_size_read(&vnode->netfs.inode);
+	if (write_end_pos > i_size) {
 		write_seqlock(&vnode->cb_lock);
-		i_size = i_size_read(&vnode->vfs_inode);
-		if (maybe_i_size > i_size)
-			afs_set_i_size(vnode, maybe_i_size);
+		i_size = i_size_read(&vnode->netfs.inode);
+		if (write_end_pos > i_size)
+			afs_set_i_size(vnode, write_end_pos);
 		write_sequnlock(&vnode->cb_lock);
+		fscache_update_cookie(afs_vnode_cache(vnode), NULL, &write_end_pos);
 	}
 
 	if (folio_test_private(folio)) {
@@ -243,7 +257,7 @@ static void afs_redirty_pages(struct writeback_control *wbc,
  */
 static void afs_pages_written_back(struct afs_vnode *vnode, loff_t start, unsigned int len)
 {
-	struct address_space *mapping = vnode->vfs_inode.i_mapping;
+	struct address_space *mapping = vnode->netfs.inode.i_mapping;
 	struct folio *folio;
 	pgoff_t end;
 
@@ -342,7 +356,7 @@ static int afs_store_data(struct afs_vnode *vnode, struct iov_iter *iter, loff_t
 {
 	struct afs_operation *op;
 	struct afs_wb_key *wbk = NULL;
-	loff_t size = iov_iter_count(iter), i_size;
+	loff_t size = iov_iter_count(iter);
 	int ret = -ENOKEY;
 
 	_enter("%s{%llx:%llu.%u},%llx,%llx",
@@ -364,17 +378,15 @@ static int afs_store_data(struct afs_vnode *vnode, struct iov_iter *iter, loff_t
 		return -ENOMEM;
 	}
 
-	i_size = i_size_read(&vnode->vfs_inode);
-
 	afs_op_set_vnode(op, 0, vnode);
 	op->file[0].dv_delta = 1;
 	op->file[0].modification = true;
 	op->store.write_iter = iter;
 	op->store.pos = pos;
 	op->store.size = size;
-	op->store.i_size = max(pos + size, i_size);
+	op->store.i_size = max(pos + size, vnode->netfs.remote_i_size);
 	op->store.laundering = laundering;
-	op->mtime = vnode->vfs_inode.i_mtime;
+	op->mtime = vnode->netfs.inode.i_mtime;
 	op->flags |= AFS_OPERATION_UNINTR;
 	op->ops = &afs_store_data_operation;
 
@@ -418,6 +430,7 @@ static void afs_extend_writeback(struct address_space *mapping,
 				 loff_t start,
 				 loff_t max_len,
 				 bool new_content,
+				 bool caching,
 				 unsigned int *_len)
 {
 	struct pagevec pvec;
@@ -464,7 +477,9 @@ static void afs_extend_writeback(struct address_space *mapping,
 				folio_put(folio);
 				break;
 			}
-			if (!folio_test_dirty(folio) || folio_test_writeback(folio)) {
+			if (!folio_test_dirty(folio) ||
+			    folio_test_writeback(folio) ||
+			    folio_test_fscache(folio)) {
 				folio_unlock(folio);
 				folio_put(folio);
 				break;
@@ -512,6 +527,7 @@ static void afs_extend_writeback(struct address_space *mapping,
 				BUG();
 			if (folio_start_writeback(folio))
 				BUG();
+			afs_folio_start_fscache(caching, folio);
 
 			*_count -= folio_nr_pages(folio);
 			folio_unlock(folio);
@@ -537,8 +553,9 @@ static ssize_t afs_write_back_from_locked_folio(struct address_space *mapping,
 	struct iov_iter iter;
 	unsigned long priv;
 	unsigned int offset, to, len, max_len;
-	loff_t i_size = i_size_read(&vnode->vfs_inode);
+	loff_t i_size = i_size_read(&vnode->netfs.inode);
 	bool new_content = test_bit(AFS_VNODE_NEW_CONTENT, &vnode->flags);
+	bool caching = fscache_cookie_enabled(afs_vnode_cache(vnode));
 	long count = wbc->nr_to_write;
 	int ret;
 
@@ -546,6 +563,7 @@ static ssize_t afs_write_back_from_locked_folio(struct address_space *mapping,
 
 	if (folio_start_writeback(folio))
 		BUG();
+	afs_folio_start_fscache(caching, folio);
 
 	count -= folio_nr_pages(folio);
 
@@ -572,7 +590,8 @@ static ssize_t afs_write_back_from_locked_folio(struct address_space *mapping,
 		if (len < max_len &&
 		    (to == folio_size(folio) || new_content))
 			afs_extend_writeback(mapping, vnode, &count,
-					     start, max_len, new_content, &len);
+					     start, max_len, new_content,
+					     caching, &len);
 		len = min_t(loff_t, len, max_len);
 	}
 
@@ -585,12 +604,18 @@ static ssize_t afs_write_back_from_locked_folio(struct address_space *mapping,
 	if (start < i_size) {
 		_debug("write back %x @%llx [%llx]", len, start, i_size);
 
+		/* Speculatively write to the cache.  We have to fix this up
+		 * later if the store fails.
+		 */
+		afs_write_to_cache(vnode, start, len, i_size, caching);
+
 		iov_iter_xarray(&iter, WRITE, &mapping->i_pages, start, len);
 		ret = afs_store_data(vnode, &iter, start, false);
 	} else {
 		_debug("write discard %x @%llx [%llx]", len, start, i_size);
 
 		/* The dirty region was entirely beyond the EOF. */
+		fscache_clear_page_bits(mapping, start, len, caching);
 		afs_pages_written_back(vnode, start, len);
 		ret = 0;
 	}
@@ -610,6 +635,7 @@ static ssize_t afs_write_back_from_locked_folio(struct address_space *mapping,
 	case -EKEYEXPIRED:
 	case -EKEYREJECTED:
 	case -EKEYREVOKED:
+	case -ENETRESET:
 		afs_redirty_pages(wbc, mapping, start, len);
 		mapping_set_error(mapping, ret);
 		break;
@@ -649,6 +675,10 @@ int afs_writepage(struct page *subpage, struct writeback_control *wbc)
 
 	_enter("{%lx},", folio_index(folio));
 
+#ifdef CONFIG_AFS_FSCACHE
+	folio_wait_fscache(folio);
+#endif
+
 	start = folio_index(folio) * PAGE_SIZE;
 	ret = afs_write_back_from_locked_folio(folio_mapping(folio), wbc,
 					       folio, start, LLONG_MAX - start);
@@ -671,7 +701,7 @@ static int afs_writepages_region(struct address_space *mapping,
 	struct folio *folio;
 	struct page *head_page;
 	ssize_t ret;
-	int n;
+	int n, skips = 0;
 
 	_enter("%llx,%llx,", start, end);
 
@@ -714,11 +744,23 @@ static int afs_writepages_region(struct address_space *mapping,
 			continue;
 		}
 
-		if (folio_test_writeback(folio)) {
+		if (folio_test_writeback(folio) ||
+		    folio_test_fscache(folio)) {
 			folio_unlock(folio);
-			if (wbc->sync_mode != WB_SYNC_NONE)
+			if (wbc->sync_mode != WB_SYNC_NONE) {
 				folio_wait_writeback(folio);
+#ifdef CONFIG_AFS_FSCACHE
+				folio_wait_fscache(folio);
+#endif
+			} else {
+				start += folio_size(folio);
+			}
 			folio_put(folio);
+			if (wbc->sync_mode == WB_SYNC_NONE) {
+				if (skips >= 5 || need_resched())
+					break;
+				skips++;
+			}
 			continue;
 		}
 
@@ -802,7 +844,7 @@ ssize_t afs_file_write(struct kiocb *iocb, struct iov_iter *from)
 	_enter("{%llx:%llu},{%zu},",
 	       vnode->fid.vid, vnode->fid.vnode, count);
 
-	if (IS_SWAPFILE(&vnode->vfs_inode)) {
+	if (IS_SWAPFILE(&vnode->netfs.inode)) {
 		printk(KERN_INFO
 		       "AFS: Attempt to write to active swap file!\n");
 		return -EBUSY;
@@ -915,8 +957,8 @@ void afs_prune_wb_keys(struct afs_vnode *vnode)
 	/* Discard unused keys */
 	spin_lock(&vnode->wb_lock);
 
-	if (!mapping_tagged(&vnode->vfs_inode.i_data, PAGECACHE_TAG_WRITEBACK) &&
-	    !mapping_tagged(&vnode->vfs_inode.i_data, PAGECACHE_TAG_DIRTY)) {
+	if (!mapping_tagged(&vnode->netfs.inode.i_data, PAGECACHE_TAG_WRITEBACK) &&
+	    !mapping_tagged(&vnode->netfs.inode.i_data, PAGECACHE_TAG_DIRTY)) {
 		list_for_each_entry_safe(wbk, tmp, &vnode->wb_keys, vnode_link) {
 			if (refcount_read(&wbk->usage) == 1)
 				list_move(&wbk->vnode_link, &graveyard);
@@ -935,9 +977,8 @@ void afs_prune_wb_keys(struct afs_vnode *vnode)
 /*
  * Clean up a page during invalidation.
  */
-int afs_launder_page(struct page *subpage)
+int afs_launder_folio(struct folio *folio)
 {
-	struct folio *folio = page_folio(subpage);
 	struct afs_vnode *vnode = AFS_FS_I(folio_inode(folio));
 	struct iov_iter iter;
 	struct bio_vec bv[1];
@@ -945,7 +986,7 @@ int afs_launder_page(struct page *subpage)
 	unsigned int f, t;
 	int ret = 0;
 
-	_enter("{%lx}", folio_index(folio));
+	_enter("{%lx}", folio->index);
 
 	priv = (unsigned long)folio_get_private(folio);
 	if (folio_clear_dirty_for_io(folio)) {
@@ -970,3 +1011,28 @@ int afs_launder_page(struct page *subpage)
 	folio_wait_fscache(folio);
 	return ret;
 }
+
+/*
+ * Deal with the completion of writing the data to the cache.
+ */
+static void afs_write_to_cache_done(void *priv, ssize_t transferred_or_error,
+				    bool was_async)
+{
+	struct afs_vnode *vnode = priv;
+
+	if (IS_ERR_VALUE(transferred_or_error) &&
+	    transferred_or_error != -ENOBUFS)
+		afs_invalidate_cache(vnode, 0);
+}
+
+/*
+ * Save the write to the cache also.
+ */
+static void afs_write_to_cache(struct afs_vnode *vnode,
+			       loff_t start, size_t len, loff_t i_size,
+			       bool caching)
+{
+	fscache_write_to_cache(afs_vnode_cache(vnode),
+			       vnode->netfs.inode.i_mapping, start, len, i_size,
+			       afs_write_to_cache_done, vnode, caching);
+}