NFS: Always enable NFS direct I/O (ecfc555a) · Commits · 戴 / test

fs/Kconfig

+0 −24

Original line number	Diff line number	Diff line
		@@ -1637,30 +1637,6 @@ config NFS_V4

		If unsure, say N.

		config NFS_DIRECTIO
		bool "Allow direct I/O on NFS files"
		depends on NFS_FS
		help
		This option enables applications to perform uncached I/O on files
		in NFS file systems using the O_DIRECT open() flag. When O_DIRECT
		is set for a file, its data is not cached in the system's page
		cache. Data is moved to and from user-level application buffers
		directly. Unlike local disk-based file systems, NFS O_DIRECT has
		no alignment restrictions.

		Unless your program is designed to use O_DIRECT properly, you are
		much better off allowing the NFS client to manage data caching for
		you. Misusing O_DIRECT can cause poor server performance or network
		storms. This kernel build option defaults OFF to avoid exposing
		system administrators unwittingly to a potentially hazardous
		feature.

		For more details on NFS O_DIRECT, see fs/nfs/direct.c.

		If unsure, say N. This reduces the size of the NFS client, and
		causes open() to return EINVAL if a file residing in NFS is
		opened with the O_DIRECT flag.

		config NFSD
		tristate "NFS server support"
		depends on INET

+1 −2

Original line number	Diff line number	Diff line
		@@ -5,7 +5,7 @@
		obj-$(CONFIG_NFS_FS) += nfs.o

		nfs-y := client.o dir.o file.o getroot.o inode.o super.o nfs2xdr.o \
		pagelist.o proc.o read.o symlink.o unlink.o \
		direct.o pagelist.o proc.o read.o symlink.o unlink.o \
		write.o namespace.o mount_clnt.o
		nfs-$(CONFIG_ROOT_NFS) += nfsroot.o
		nfs-$(CONFIG_NFS_V3) += nfs3proc.o nfs3xdr.o
		@@ -14,5 +14,4 @@ nfs-$(CONFIG_NFS_V4) += nfs4proc.o nfs4xdr.o nfs4state.o nfs4renewd.o \
		delegation.o idmap.o \
		callback.o callback_xdr.o callback_proc.o \
		nfs4namespace.o
		nfs-$(CONFIG_NFS_DIRECTIO) += direct.o
		nfs-$(CONFIG_SYSCTL) += sysctl.o

+0 −6

Original line number	Diff line number	Diff line
		@@ -234,10 +234,8 @@ nfs_file_read(struct kiocb iocb, const struct iovec iov,
		ssize_t result;
		size_t count = iov_length(iov, nr_segs);

		#ifdef CONFIG_NFS_DIRECTIO
		if (iocb->ki_filp->f_flags & O_DIRECT)
		return nfs_file_direct_read(iocb, iov, nr_segs, pos);
		#endif

		dfprintk(VFS, "nfs: read(%s/%s, %lu@%lu)\n",
		dentry->d_parent->d_name.name, dentry->d_name.name,
		@@ -383,9 +381,7 @@ const struct address_space_operations nfs_file_aops = {
		.write_end = nfs_write_end,
		.invalidatepage = nfs_invalidate_page,
		.releasepage = nfs_release_page,
		#ifdef CONFIG_NFS_DIRECTIO
		.direct_IO = nfs_direct_IO,
		#endif
		.launder_page = nfs_launder_page,
		};

		@@ -443,10 +439,8 @@ static ssize_t nfs_file_write(struct kiocb iocb, const struct iovec iov,
		ssize_t result;
		size_t count = iov_length(iov, nr_segs);

		#ifdef CONFIG_NFS_DIRECTIO
		if (iocb->ki_filp->f_flags & O_DIRECT)
		return nfs_file_direct_write(iocb, iov, nr_segs, pos);
		#endif

		dfprintk(VFS, "nfs: write(%s/%s(%ld), %lu@%Ld)\n",
		dentry->d_parent->d_name.name, dentry->d_name.name,

+0 −5

Original line number	Diff line number	Diff line
		@@ -116,13 +116,8 @@ extern void nfs_destroy_readpagecache(void);
		extern int __init nfs_init_writepagecache(void);
		extern void nfs_destroy_writepagecache(void);

		#ifdef CONFIG_NFS_DIRECTIO
		extern int __init nfs_init_directcache(void);
		extern void nfs_destroy_directcache(void);
		#else
		#define nfs_init_directcache() (0)
		#define nfs_destroy_directcache() do {} while(0)
		#endif

		/* nfs2xdr.c */
		extern int nfs_stat_to_errno(int);