Commit 5fe0fc9f authored by Peng Hao's avatar Peng Hao Committed by Miklos Szeredi
Browse files

fuse: use kmap_local_page() 

Due to the introduction of kmap_local_*, the storage of slots used for
short-term mapping has changed from per-CPU to per-thread.  kmap_atomic()
disable preemption, while kmap_local_*() only disable migration.

There is no need to disable preemption in several kamp_atomic places used
in fuse.

Link: https://lwn.net/Articles/836144/


Signed-off-by: default avatarPeng Hao <flyingpeng@tencent.com>
Signed-off-by: default avatarMiklos Szeredi <mszeredi@redhat.com>
parent bda9a719

fs/fuse/dev.c

+4 −4
Original line number Diff line number Diff line
@@ -756,7 +756,7 @@ static int fuse_copy_do(struct fuse_copy_state *cs, void **val, unsigned *size) 
{

	unsigned ncpy = min(*size, cs->len);

	if (val) {

		void *pgaddr = kmap_atomic(cs->pg);

		void *pgaddr = kmap_local_page(cs->pg);

		void *buf = pgaddr + cs->offset;



		if (cs->write)
@@ -764,7 +764,7 @@ static int fuse_copy_do(struct fuse_copy_state *cs, void **val, unsigned *size) 
		else

			memcpy(*val, buf, ncpy);



		kunmap_atomic(pgaddr);

		kunmap_local(pgaddr);

		*val += ncpy;

	}

	*size -= ncpy;
@@ -949,10 +949,10 @@ static int fuse_copy_page(struct fuse_copy_state *cs, struct page **pagep, 
			}

		}

		if (page) {

			void *mapaddr = kmap_atomic(page);

			void *mapaddr = kmap_local_page(page);

			void *buf = mapaddr + offset;

			offset += fuse_copy_do(cs, &buf, &count);

			kunmap_atomic(mapaddr);

			kunmap_local(mapaddr);

		} else

			offset += fuse_copy_do(cs, NULL, &count);

	}

fs/fuse/ioctl.c

+2 −2
Original line number Diff line number Diff line
@@ -286,11 +286,11 @@ long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg, 
		    in_iovs + out_iovs > FUSE_IOCTL_MAX_IOV)

			goto out;



		vaddr = kmap_atomic(ap.pages[0]);

		vaddr = kmap_local_page(ap.pages[0]);

		err = fuse_copy_ioctl_iovec(fm->fc, iov_page, vaddr,

					    transferred, in_iovs + out_iovs,

					    (flags & FUSE_IOCTL_COMPAT) != 0);

		kunmap_atomic(vaddr);

		kunmap_local(vaddr);

		if (err)

			goto out;

fs/fuse/readdir.c

+2 −2
Original line number Diff line number Diff line
@@ -76,11 +76,11 @@ static void fuse_add_dirent_to_cache(struct file *file, 
	    WARN_ON(fi->rdc.pos != pos))

		goto unlock;



	addr = kmap_atomic(page);

	addr = kmap_local_page(page);

	if (!offset)

		clear_page(addr);

	memcpy(addr + offset, dirent, reclen);

	kunmap_atomic(addr);

	kunmap_local(addr);

	fi->rdc.size = (index << PAGE_SHIFT) + offset + reclen;

	fi->rdc.pos = dirent->off;

unlock: