[v6,26/34] cifs: Add some helper functions

Commit Message

David Howells Jan. 16, 2023, 11:11 p.m. UTC

Add some helper functions to manipulate the folio marks by iterating
through a list of folios held in an xarray rather than using a page list.

Signed-off-by: David Howells <[e-mail]>
cc: Steve French <[e-mail]>
cc: Shyam Prasad N <[e-mail]>
cc: Rohith Surabattula <[e-mail]>
cc: Jeff Layton <[e-mail]>
cc: [e-mail]

Link: https://lore.kernel.org/r/[e-mail]/ # v1
Link: https://lore.kernel.org/r/[e-mail]/ # v1
Link: https://lore.kernel.org/r/[e-mail]/ # v1
Link: https://lore.kernel.org/r/[e-mail]/ # v3
Link: https://lore.kernel.org/r/[e-mail]/ # v1
Link: https://lore.kernel.org/r/[e-mail]/ # rfc
Link: https://lore.kernel.org/r/[e-mail]/ # rfc
---

 fs/cifs/cifsfs.h |    3 ++
 fs/cifs/file.c   |   93 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 96 insertions(+)

Patch

diff --git a/fs/cifs/cifsfs.h b/fs/cifs/cifsfs.h
index 25decebbc478..ea628da503c6 100644
--- a/fs/cifs/cifsfs.h
+++ b/fs/cifs/cifsfs.h
@@ -113,6 +113,9 @@  extern int cifs_file_strict_mmap(struct file *file, struct vm_area_struct *vma);
 extern const struct file_operations cifs_dir_ops;
 extern int cifs_dir_open(struct inode *inode, struct file *file);
 extern int cifs_readdir(struct file *file, struct dir_context *ctx);
+extern void cifs_pages_written_back(struct inode *inode, loff_t start, unsigned int len);
+extern void cifs_pages_write_failed(struct inode *inode, loff_t start, unsigned int len);
+extern void cifs_pages_write_redirty(struct inode *inode, loff_t start, unsigned int len);
 
 /* Functions related to dir entries */
 extern const struct dentry_operations cifs_dentry_ops;
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index f1297386a185..2873f28bf388 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -36,6 +36,99 @@ 
 #include "cifs_ioctl.h"
 #include "cached_dir.h"
 
+/*
+ * Completion of write to server.
+ */
+void cifs_pages_written_back(struct inode *inode, loff_t start, unsigned int len)
+{
+	struct address_space *mapping = inode->i_mapping;
+	struct folio *folio;
+	pgoff_t end;
+
+	XA_STATE(xas, &mapping->i_pages, start / PAGE_SIZE);
+
+	if (!len)
+		return;
+
+	rcu_read_lock();
+
+	end = (start + len - 1) / PAGE_SIZE;
+	xas_for_each(&xas, folio, end) {
+		if (!folio_test_writeback(folio)) {
+			WARN_ONCE(1, "bad %x @%llx page %lx %lx\n",
+				  len, start, folio_index(folio), end);
+			continue;
+		}
+
+		folio_detach_private(folio);
+		folio_end_writeback(folio);
+	}
+
+	rcu_read_unlock();
+}
+
+/*
+ * Failure of write to server.
+ */
+void cifs_pages_write_failed(struct inode *inode, loff_t start, unsigned int len)
+{
+	struct address_space *mapping = inode->i_mapping;
+	struct folio *folio;
+	pgoff_t end;
+
+	XA_STATE(xas, &mapping->i_pages, start / PAGE_SIZE);
+
+	if (!len)
+		return;
+
+	rcu_read_lock();
+
+	end = (start + len - 1) / PAGE_SIZE;
+	xas_for_each(&xas, folio, end) {
+		if (!folio_test_writeback(folio)) {
+			WARN_ONCE(1, "bad %x @%llx page %lx %lx\n",
+				  len, start, folio_index(folio), end);
+			continue;
+		}
+
+		folio_set_error(folio);
+		folio_end_writeback(folio);
+	}
+
+	rcu_read_unlock();
+}
+
+/*
+ * Redirty pages after a temporary failure.
+ */
+void cifs_pages_write_redirty(struct inode *inode, loff_t start, unsigned int len)
+{
+	struct address_space *mapping = inode->i_mapping;
+	struct folio *folio;
+	pgoff_t end;
+
+	XA_STATE(xas, &mapping->i_pages, start / PAGE_SIZE);
+
+	if (!len)
+		return;
+
+	rcu_read_lock();
+
+	end = (start + len - 1) / PAGE_SIZE;
+	xas_for_each(&xas, folio, end) {
+		if (!folio_test_writeback(folio)) {
+			WARN_ONCE(1, "bad %x @%llx page %lx %lx\n",
+				  len, start, folio_index(folio), end);
+			continue;
+		}
+
+		filemap_dirty_folio(folio->mapping, folio);
+		folio_end_writeback(folio);
+	}
+
+	rcu_read_unlock();
+}
+
 /*
  * Mark as invalid, all open files on tree connections since they
  * were closed when session to server was lost.