diff mbox series

[13/21] btrfs: Perform memory faults under locked extent

Message ID 1f8fe6c93e54b3bbf42c48c55884f3c7a56f1e94.1677793433.git.rgoldwyn@suse.com (mailing list archive)
State New, archived
Headers show
Series Lock extents before pages | expand

Commit Message

Goldwyn Rodrigues March 2, 2023, 10:24 p.m. UTC 
From: Goldwyn Rodrigues <rgoldwyn@suse.com>

As a part of locking extents before pages, lock entire memfault region
while servicing faults.

Remove extent locking from page_mkwrite(), since it is part of the
fault.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
---
 fs/btrfs/file.c  | 18 +++++++++++++++++-
 fs/btrfs/inode.c |  6 ------
 2 files changed, 17 insertions(+), 7 deletions(-)
diff mbox series

Patch

diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 2e835096e3ce..fe1f63456142 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -1973,8 +1973,24 @@  int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
 	goto out;
 }
 
+static vm_fault_t btrfs_fault(struct vm_fault *vmf)
+{
+	struct extent_state *cached_state = NULL;
+	struct inode *inode = file_inode(vmf->vma->vm_file);
+	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
+	u64 page_start = round_down(vmf->pgoff, PAGE_SIZE);
+	u64 page_end = page_start + PAGE_SIZE - 1;
+	vm_fault_t ret;
+
+	lock_extent(io_tree, page_start, page_end, &cached_state);
+	ret = filemap_fault(vmf);
+	unlock_extent(io_tree, page_start, page_end, &cached_state);
+
+	return ret;
+}
+
 static const struct vm_operations_struct btrfs_file_vm_ops = {
-	.fault		= filemap_fault,
+	.fault		= btrfs_fault,
 	.map_pages	= filemap_map_pages,
 	.page_mkwrite	= btrfs_page_mkwrite,
 };
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index fb02b2b3ac2e..ed3553ff2c31 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -8132,7 +8132,6 @@  vm_fault_t btrfs_page_mkwrite(struct vm_fault *vmf)
 	struct page *page = vmf->page;
 	struct inode *inode = file_inode(vmf->vma->vm_file);
 	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
-	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 	struct btrfs_ordered_extent *ordered;
 	struct extent_state *cached_state = NULL;
 	struct extent_changeset *data_reserved = NULL;
@@ -8187,11 +8186,9 @@  vm_fault_t btrfs_page_mkwrite(struct vm_fault *vmf)
 	}
 	wait_on_page_writeback(page);
 
-	lock_extent(io_tree, page_start, page_end, &cached_state);
 	ret2 = set_page_extent_mapped(page);
 	if (ret2 < 0) {
 		ret = vmf_error(ret2);
-		unlock_extent(io_tree, page_start, page_end, &cached_state);
 		goto out_unlock;
 	}
 
@@ -8202,7 +8199,6 @@  vm_fault_t btrfs_page_mkwrite(struct vm_fault *vmf)
 	ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), page_start,
 			PAGE_SIZE);
 	if (ordered) {
-		unlock_extent(io_tree, page_start, page_end, &cached_state);
 		unlock_page(page);
 		up_read(&BTRFS_I(inode)->i_mmap_lock);
 		btrfs_start_ordered_extent(ordered);
@@ -8235,7 +8231,6 @@  vm_fault_t btrfs_page_mkwrite(struct vm_fault *vmf)
 	ret2 = btrfs_set_extent_delalloc(BTRFS_I(inode), page_start, end, 0,
 					&cached_state);
 	if (ret2) {
-		unlock_extent(io_tree, page_start, page_end, &cached_state);
 		ret = VM_FAULT_SIGBUS;
 		goto out_unlock;
 	}
@@ -8255,7 +8250,6 @@  vm_fault_t btrfs_page_mkwrite(struct vm_fault *vmf)
 
 	btrfs_set_inode_last_sub_trans(BTRFS_I(inode));
 
-	unlock_extent(io_tree, page_start, page_end, &cached_state);
 	up_read(&BTRFS_I(inode)->i_mmap_lock);
 
 	btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE);