Commit bbf0d006 authored by Jens Axboe's avatar Jens Axboe Committed by Chris Mason
Browse files

Btrfs: KM_IRQ0 usage in end_io handling 



endio handling is typically called with interrupts disabled, but can
also be called with it enabled. So save interrupts before using KM_IRQ0
to be completely safe.

Signed-off-by: default avatarChris Mason <chris.mason@oracle.com>
parent 0a2118df

fs/btrfs/inode.c

+4 −0
Original line number Diff line number Diff line
@@ -168,8 +168,10 @@ int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end) 
	int ret;

	struct btrfs_root *root = BTRFS_I(inode)->root;

	u32 csum = ~(u32)0;

	unsigned long flags;



	ret = get_state_private(em_tree, start, &private);

	local_irq_save(flags);

	kaddr = kmap_atomic(page, KM_IRQ0);

	if (ret) {

		goto zeroit;
@@ -180,6 +182,7 @@ int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end) 
		goto zeroit;

	}

	kunmap_atomic(kaddr, KM_IRQ0);

	local_irq_restore(flags);

	return 0;



zeroit:
@@ -188,6 +191,7 @@ int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end) 
	memset(kaddr + offset, 1, end - start + 1);

	flush_dcache_page(page);

	kunmap_atomic(kaddr, KM_IRQ0);

	local_irq_restore(flags);

	return 0;

}