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-rw-r--r--fs/nfs/Makefile2
-rw-r--r--fs/nfs/export.c177
-rw-r--r--fs/nfs/internal.h2
-rw-r--r--fs/nfs/super.c2
4 files changed, 182 insertions, 1 deletions
diff --git a/fs/nfs/Makefile b/fs/nfs/Makefile
index 98f4e5728a67..1fb118902d57 100644
--- a/fs/nfs/Makefile
+++ b/fs/nfs/Makefile
@@ -7,7 +7,7 @@ obj-$(CONFIG_NFS_FS) += nfs.o
CFLAGS_nfstrace.o += -I$(src)
nfs-y := client.o dir.o file.o getroot.o inode.o super.o \
io.o direct.o pagelist.o read.o symlink.o unlink.o \
- write.o namespace.o mount_clnt.o nfstrace.o
+ write.o namespace.o mount_clnt.o nfstrace.o export.o
nfs-$(CONFIG_ROOT_NFS) += nfsroot.o
nfs-$(CONFIG_SYSCTL) += sysctl.o
nfs-$(CONFIG_NFS_FSCACHE) += fscache.o fscache-index.o
diff --git a/fs/nfs/export.c b/fs/nfs/export.c
new file mode 100644
index 000000000000..249cb96cc5b5
--- /dev/null
+++ b/fs/nfs/export.c
@@ -0,0 +1,177 @@
+/*
+ * Copyright (c) 2015, Primary Data, Inc. All rights reserved.
+ *
+ * Tao Peng <bergwolf@primarydata.com>
+ */
+#include <linux/dcache.h>
+#include <linux/exportfs.h>
+#include <linux/nfs.h>
+#include <linux/nfs_fs.h>
+
+#include "internal.h"
+#include "nfstrace.h"
+
+#define NFSDBG_FACILITY NFSDBG_VFS
+
+enum {
+ FILEID_HIGH_OFF = 0, /* inode fileid high */
+ FILEID_LOW_OFF, /* inode fileid low */
+ FILE_I_TYPE_OFF, /* inode type */
+ EMBED_FH_OFF /* embeded server fh */
+};
+
+
+static struct nfs_fh *nfs_exp_embedfh(__u32 *p)
+{
+ return (struct nfs_fh *)(p + EMBED_FH_OFF);
+}
+
+/*
+ * Let's break subtree checking for now... otherwise we'll have to embed parent fh
+ * but there might not be enough space.
+ */
+static int
+nfs_encode_fh(struct inode *inode, __u32 *p, int *max_len, struct inode *parent)
+{
+ struct nfs_fh *server_fh = NFS_FH(inode);
+ struct nfs_fh *clnt_fh = nfs_exp_embedfh(p);
+ size_t fh_size = offsetof(struct nfs_fh, data) + server_fh->size;
+ int len = EMBED_FH_OFF + XDR_QUADLEN(fh_size);
+
+ dprintk("%s: max fh len %d inode %p parent %p",
+ __func__, *max_len, inode, parent);
+
+ if (*max_len < len || IS_AUTOMOUNT(inode)) {
+ dprintk("%s: fh len %d too small, required %d\n",
+ __func__, *max_len, len);
+ *max_len = len;
+ return FILEID_INVALID;
+ }
+ if (IS_AUTOMOUNT(inode)) {
+ *max_len = FILEID_INVALID;
+ goto out;
+ }
+
+ p[FILEID_HIGH_OFF] = NFS_FILEID(inode) >> 32;
+ p[FILEID_LOW_OFF] = NFS_FILEID(inode);
+ p[FILE_I_TYPE_OFF] = inode->i_mode & S_IFMT;
+ p[len - 1] = 0; /* Padding */
+ nfs_copy_fh(clnt_fh, server_fh);
+ *max_len = len;
+out:
+ dprintk("%s: result fh fileid %llu mode %u size %d\n",
+ __func__, NFS_FILEID(inode), inode->i_mode, *max_len);
+ return *max_len;
+}
+
+static struct dentry *
+nfs_fh_to_dentry(struct super_block *sb, struct fid *fid,
+ int fh_len, int fh_type)
+{
+ struct nfs4_label *label = NULL;
+ struct nfs_fattr *fattr = NULL;
+ struct nfs_fh *server_fh = nfs_exp_embedfh(fid->raw);
+ size_t fh_size = offsetof(struct nfs_fh, data) + server_fh->size;
+ const struct nfs_rpc_ops *rpc_ops;
+ struct dentry *dentry;
+ struct inode *inode;
+ int len = EMBED_FH_OFF + XDR_QUADLEN(fh_size);
+ u32 *p = fid->raw;
+ int ret;
+
+ /* NULL translates to ESTALE */
+ if (fh_len < len || fh_type != len)
+ return NULL;
+
+ fattr = nfs_alloc_fattr();
+ if (fattr == NULL) {
+ dentry = ERR_PTR(-ENOMEM);
+ goto out;
+ }
+
+ fattr->fileid = ((u64)p[FILEID_HIGH_OFF] << 32) + p[FILEID_LOW_OFF];
+ fattr->mode = p[FILE_I_TYPE_OFF];
+ fattr->valid |= NFS_ATTR_FATTR_FILEID | NFS_ATTR_FATTR_TYPE;
+
+ dprintk("%s: fileid %llu mode %d\n", __func__, fattr->fileid, fattr->mode);
+
+ inode = nfs_ilookup(sb, fattr, server_fh);
+ if (inode)
+ goto out_found;
+
+ label = nfs4_label_alloc(NFS_SB(sb), GFP_KERNEL);
+ if (IS_ERR(label)) {
+ dentry = ERR_CAST(label);
+ goto out_free_fattr;
+ }
+
+ rpc_ops = NFS_SB(sb)->nfs_client->rpc_ops;
+ ret = rpc_ops->getattr(NFS_SB(sb), server_fh, fattr, label);
+ if (ret) {
+ dprintk("%s: getattr failed %d\n", __func__, ret);
+ dentry = ERR_PTR(ret);
+ goto out_free_label;
+ }
+
+ inode = nfs_fhget(sb, server_fh, fattr, label);
+
+out_found:
+ dentry = d_obtain_alias(inode);
+
+out_free_label:
+ nfs4_label_free(label);
+out_free_fattr:
+ nfs_free_fattr(fattr);
+out:
+ return dentry;
+}
+
+static struct dentry *
+nfs_get_parent(struct dentry *dentry)
+{
+ int ret;
+ struct inode *inode = d_inode(dentry), *pinode;
+ struct super_block *sb = inode->i_sb;
+ struct nfs_server *server = NFS_SB(sb);
+ struct nfs_fattr *fattr = NULL;
+ struct nfs4_label *label = NULL;
+ struct dentry *parent;
+ struct nfs_rpc_ops const *ops = server->nfs_client->rpc_ops;
+ struct nfs_fh fh;
+
+ if (!ops->lookupp)
+ return ERR_PTR(-EACCES);
+
+ fattr = nfs_alloc_fattr();
+ if (fattr == NULL) {
+ parent = ERR_PTR(-ENOMEM);
+ goto out;
+ }
+
+ label = nfs4_label_alloc(server, GFP_KERNEL);
+ if (IS_ERR(label)) {
+ parent = ERR_CAST(label);
+ goto out_free_fattr;
+ }
+
+ ret = ops->lookupp(inode, &fh, fattr, label);
+ if (ret) {
+ parent = ERR_PTR(ret);
+ goto out_free_label;
+ }
+
+ pinode = nfs_fhget(sb, &fh, fattr, label);
+ parent = d_obtain_alias(pinode);
+out_free_label:
+ nfs4_label_free(label);
+out_free_fattr:
+ nfs_free_fattr(fattr);
+out:
+ return parent;
+}
+
+const struct export_operations nfs_export_ops = {
+ .encode_fh = nfs_encode_fh,
+ .fh_to_dentry = nfs_fh_to_dentry,
+ .get_parent = nfs_get_parent,
+};
diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index c5054edb0157..2ebd57498986 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -10,6 +10,8 @@
#define NFS_MS_MASK (MS_RDONLY|MS_NOSUID|MS_NODEV|MS_NOEXEC|MS_SYNCHRONOUS)
+extern const struct export_operations nfs_export_ops;
+
struct nfs_string;
/* Maximum number of readahead requests
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index b4176393f049..b5271644b472 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -2339,6 +2339,7 @@ void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
*/
sb->s_flags |= MS_POSIXACL;
sb->s_time_gran = 1;
+ sb->s_export_op = &nfs_export_ops;
}
nfs_initialise_sb(sb);
@@ -2360,6 +2361,7 @@ static void nfs_clone_super(struct super_block *sb,
sb->s_xattr = old_sb->s_xattr;
sb->s_op = old_sb->s_op;
sb->s_time_gran = 1;
+ sb->s_export_op = old_sb->s_export_op;
if (server->nfs_client->rpc_ops->version != 2) {
/* The VFS shouldn't apply the umask to mode bits. We will do