[PATCH v6 25/27] NFS: Add fs_context support.

From: Scott Mayhew
Date: Tue Dec 10 2019 - 07:31:45 EST


From: David Howells <dhowells@xxxxxxxxxx>

Add filesystem context support to NFS, parsing the options in advance and
attaching the information to struct nfs_fs_context. The highlights are:

(*) Merge nfs_mount_info and nfs_clone_mount into nfs_fs_context. This
structure represents NFS's superblock config.

(*) Make use of the VFS's parsing support to split comma-separated lists

(*) Pin the NFS protocol module in the nfs_fs_context.

(*) Attach supplementary error information to fs_context. This has the
downside that these strings must be static and can't be formatted.

(*) Remove the auxiliary file_system_type structs since the information
necessary can be conveyed in the nfs_fs_context struct instead.

(*) Root mounts are made by duplicating the config for the requested mount
so as to have the same parameters. Submounts pick up their parameters
from the parent superblock.

[AV -- retrans is u32, not string]
[SM -- Renamed cfg to ctx in a few functions in an earlier patch]
[SM -- Moved fs_context mount option parsing to an earlier patch]
[SM -- Moved fs_context error logging to a later patch]
[SM -- Fixed printks in nfs4_try_get_tree() and nfs4_get_referral_tree()]
[SM -- Added is_remount_fc() helper]
[SM -- Deferred some refactoring to a later patch]
[SM -- Fixed referral mounts, which were broken in the original patch]
[SM -- Fixed leak of nfs_fattr when fs_context is freed]

Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Scott Mayhew <smayhew@xxxxxxxxxx>
---
fs/nfs/fs_context.c | 470 +++++++++++++++++++++++++++-------------
fs/nfs/internal.h | 74 +++----
fs/nfs/namespace.c | 136 +++++++-----
fs/nfs/nfs3proc.c | 2 +-
fs/nfs/nfs4_fs.h | 9 +-
fs/nfs/nfs4file.c | 1 +
fs/nfs/nfs4namespace.c | 293 ++++++++++++++-----------
fs/nfs/nfs4proc.c | 2 +-
fs/nfs/nfs4super.c | 151 +++++++------
fs/nfs/proc.c | 2 +-
fs/nfs/super.c | 286 +++++++-----------------
include/linux/nfs_xdr.h | 6 +-
12 files changed, 773 insertions(+), 659 deletions(-)

diff --git a/fs/nfs/fs_context.c b/fs/nfs/fs_context.c
index 9a3162055d5d..ac1a8d7d7393 100644
--- a/fs/nfs/fs_context.c
+++ b/fs/nfs/fs_context.c
@@ -3,6 +3,7 @@
* linux/fs/nfs/fs_context.c
*
* Copyright (C) 1992 Rick Sladkey
+ * Conversion to new mount api Copyright (C) David Howells
*
* NFS mount handling.
*
@@ -467,21 +468,31 @@ static int nfs_parse_version_string(struct nfs_fs_context *ctx,
/*
* Parse a single mount parameter.
*/
-static int nfs_fs_context_parse_param(struct nfs_fs_context *ctx,
+static int nfs_fs_context_parse_param(struct fs_context *fc,
struct fs_parameter *param)
{
struct fs_parse_result result;
+ struct nfs_fs_context *ctx = nfs_fc2context(fc);
unsigned short protofamily, mountfamily;
unsigned int len;
int ret, opt;

dfprintk(MOUNT, "NFS: parsing nfs mount option '%s'\n", param->key);

- opt = fs_parse(NULL, &nfs_fs_parameters, param, &result);
+ opt = fs_parse(fc, &nfs_fs_parameters, param, &result);
if (opt < 0)
return ctx->sloppy ? 1 : opt;

switch (opt) {
+ case Opt_source:
+ if (fc->source) {
+ dfprintk(MOUNT, "NFS: Multiple sources not supported\n");
+ return -EINVAL;
+ }
+ fc->source = param->string;
+ param->string = NULL;
+ break;
+
/*
* boolean options: foo/nofoo
*/
@@ -807,112 +818,6 @@ static int nfs_fs_context_parse_param(struct nfs_fs_context *ctx,
return -ERANGE;
}

-/* cribbed from generic_parse_monolithic and vfs_parse_fs_string */
-static int nfs_fs_context_parse_option(struct nfs_fs_context *ctx, char *p)
-{
- int ret;
- char *key = p, *value;
- size_t v_size = 0;
- struct fs_parameter param;
-
- memset(&param, 0, sizeof(param));
- value = strchr(key, '=');
- if (value && value != key) {
- *value++ = 0;
- v_size = strlen(value);
- }
- param.key = key;
- param.type = fs_value_is_flag;
- param.size = v_size;
- if (v_size > 0) {
- param.type = fs_value_is_string;
- param.string = kmemdup_nul(value, v_size, GFP_KERNEL);
- if (!param.string)
- return -ENOMEM;
- }
- ret = nfs_fs_context_parse_param(ctx, &param);
- kfree(param.string);
- return ret;
-}
-
-/*
- * Error-check and convert a string of mount options from user space into
- * a data structure. The whole mount string is processed; bad options are
- * skipped as they are encountered. If there were no errors, return 1;
- * otherwise return 0 (zero).
- */
-int nfs_parse_mount_options(char *raw, struct nfs_fs_context *ctx)
-{
- char *p;
- int rc, sloppy = 0, invalid_option = 0;
-
- if (!raw) {
- dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
- return 1;
- }
- dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
-
- rc = security_sb_eat_lsm_opts(raw, &ctx->lsm_opts);
- if (rc)
- goto out_security_failure;
-
- while ((p = strsep(&raw, ",")) != NULL) {
- if (!*p)
- continue;
- if (nfs_fs_context_parse_option(ctx, p) < 0)
- invalid_option = true;
- }
-
- if (!sloppy && invalid_option)
- return 0;
-
- if (ctx->minorversion && ctx->version != 4)
- goto out_minorversion_mismatch;
-
- if (ctx->options & NFS_OPTION_MIGRATION &&
- (ctx->version != 4 || ctx->minorversion != 0))
- goto out_migration_misuse;
-
- /*
- * verify that any proto=/mountproto= options match the address
- * families in the addr=/mountaddr= options.
- */
- if (ctx->protofamily != AF_UNSPEC &&
- ctx->protofamily != ctx->nfs_server.address.sa_family)
- goto out_proto_mismatch;
-
- if (ctx->mountfamily != AF_UNSPEC) {
- if (ctx->mount_server.addrlen) {
- if (ctx->mountfamily != ctx->mount_server.address.sa_family)
- goto out_mountproto_mismatch;
- } else {
- if (ctx->mountfamily != ctx->nfs_server.address.sa_family)
- goto out_mountproto_mismatch;
- }
- }
-
- return 1;
-
-out_minorversion_mismatch:
- printk(KERN_INFO "NFS: mount option vers=%u does not support "
- "minorversion=%u\n", ctx->version, ctx->minorversion);
- return 0;
-out_mountproto_mismatch:
- printk(KERN_INFO "NFS: mount server address does not match mountproto= "
- "option\n");
- return 0;
-out_proto_mismatch:
- printk(KERN_INFO "NFS: server address does not match proto= option\n");
- return 0;
-out_migration_misuse:
- printk(KERN_INFO
- "NFS: 'migration' not supported for this NFS version\n");
- return -EINVAL;
-out_security_failure:
- printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
- return 0;
-}
-
/*
* Split "dev_name" into "hostname:export_path".
*
@@ -990,6 +895,11 @@ static int nfs_parse_devname(struct nfs_fs_context *ctx,
return -ENAMETOOLONG;
}

+static inline bool is_remount_fc(struct fs_context *fc)
+{
+ return fc->root != NULL;
+}
+
/*
* Parse monolithic NFS2/NFS3 mount data
* - fills in the mount root filehandle
@@ -1006,12 +916,11 @@ static int nfs_parse_devname(struct nfs_fs_context *ctx,
* + breaking back: trying proto=udp after proto=tcp, v2 after v3,
* mountproto=tcp after mountproto=udp, and so on
*/
-static int nfs23_validate_mount_data(void *options,
- struct nfs_fs_context *ctx,
- struct nfs_fh *mntfh,
- const char *dev_name)
+static int nfs23_parse_monolithic(struct fs_context *fc,
+ struct nfs_mount_data *data)
{
- struct nfs_mount_data *data = (struct nfs_mount_data *)options;
+ struct nfs_fs_context *ctx = nfs_fc2context(fc);
+ struct nfs_fh *mntfh = ctx->mount_info.mntfh;
struct sockaddr *sap = (struct sockaddr *)&ctx->nfs_server.address;
int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;

@@ -1083,6 +992,9 @@ static int nfs23_validate_mount_data(void *options,
ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
/* N.B. caller will free nfs_server.hostname in all cases */
ctx->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
+ if (!ctx->nfs_server.hostname)
+ goto out_nomem;
+
ctx->namlen = data->namlen;
ctx->bsize = data->bsize;

@@ -1090,8 +1002,6 @@ static int nfs23_validate_mount_data(void *options,
ctx->selected_flavor = data->pseudoflavor;
else
ctx->selected_flavor = RPC_AUTH_UNIX;
- if (!ctx->nfs_server.hostname)
- goto out_nomem;

if (!(data->flags & NFS_MOUNT_NONLM))
ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
@@ -1109,12 +1019,13 @@ static int nfs23_validate_mount_data(void *options,
*/
if (data->context[0]){
#ifdef CONFIG_SECURITY_SELINUX
- int rc;
+ int ret;
+
data->context[NFS_MAX_CONTEXT_LEN] = '\0';
- rc = security_add_mnt_opt("context", data->context,
- strlen(data->context), ctx->lsm_opts);
- if (rc)
- return rc;
+ ret = vfs_parse_fs_string(fc, "context",
+ data->context, strlen(data->context));
+ if (ret < 0)
+ return ret;
#else
return -EINVAL;
#endif
@@ -1122,12 +1033,20 @@ static int nfs23_validate_mount_data(void *options,

break;
default:
- return NFS_TEXT_DATA;
+ goto generic;
}

+ ctx->skip_reconfig_option_check = true;
return 0;

+generic:
+ return generic_parse_monolithic(fc, data);
+
out_no_data:
+ if (is_remount_fc(fc)) {
+ ctx->skip_reconfig_option_check = true;
+ return 0;
+ }
dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
return -EINVAL;

@@ -1163,12 +1082,11 @@ static void nfs4_validate_mount_flags(struct nfs_fs_context *ctx)
/*
* Validate NFSv4 mount options
*/
-static int nfs4_validate_mount_data(void *options,
- struct nfs_fs_context *ctx,
- const char *dev_name)
+static int nfs4_parse_monolithic(struct fs_context *fc,
+ struct nfs4_mount_data *data)
{
+ struct nfs_fs_context *ctx = nfs_fc2context(fc);
struct sockaddr *sap = (struct sockaddr *)&ctx->nfs_server.address;
- struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
char *c;

if (data == NULL)
@@ -1218,7 +1136,7 @@ static int nfs4_validate_mount_data(void *options,
ctx->client_address = c;

/*
- * Translate to nfs_fs_context, which nfs4_fill_super
+ * Translate to nfs_fs_context, which nfs_fill_super
* can deal with.
*/

@@ -1238,12 +1156,20 @@ static int nfs4_validate_mount_data(void *options,

break;
default:
- return NFS_TEXT_DATA;
+ goto generic;
}

+ ctx->skip_reconfig_option_check = true;
return 0;

+generic:
+ return generic_parse_monolithic(fc, data);
+
out_no_data:
+ if (is_remount_fc(fc)) {
+ ctx->skip_reconfig_option_check = true;
+ return 0;
+ }
dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
return -EINVAL;

@@ -1260,39 +1186,66 @@ static int nfs4_validate_mount_data(void *options,
dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
return -EINVAL;
}
+#endif

-int nfs_validate_mount_data(struct file_system_type *fs_type,
- void *options,
- struct nfs_fs_context *ctx,
- struct nfs_fh *mntfh,
- const char *dev_name)
-{
- if (fs_type == &nfs_fs_type)
- return nfs23_validate_mount_data(options, ctx, mntfh, dev_name);
- return nfs4_validate_mount_data(options, ctx, dev_name);
-}
-#else
-int nfs_validate_mount_data(struct file_system_type *fs_type,
- void *options,
- struct nfs_fs_context *ctx,
- struct nfs_fh *mntfh,
- const char *dev_name)
+/*
+ * Parse a monolithic block of data from sys_mount().
+ */
+static int nfs_fs_context_parse_monolithic(struct fs_context *fc,
+ void *data)
{
- return nfs23_validate_mount_data(options, ctx, mntfh, dev_name);
-}
+ if (fc->fs_type == &nfs_fs_type)
+ return nfs23_parse_monolithic(fc, data);
+
+#if IS_ENABLED(CONFIG_NFS_V4)
+ if (fc->fs_type == &nfs4_fs_type)
+ return nfs4_parse_monolithic(fc, data);
#endif

-int nfs_validate_text_mount_data(void *options,
- struct nfs_fs_context *ctx,
- const char *dev_name)
+ dfprintk(MOUNT, "NFS: Unsupported monolithic data version\n");
+ return -EINVAL;
+}
+
+/*
+ * Validate the preparsed information in the config.
+ */
+static int nfs_fs_context_validate(struct fs_context *fc)
{
- int port = 0;
+ struct nfs_fs_context *ctx = nfs_fc2context(fc);
+ struct nfs_subversion *nfs_mod;
+ struct sockaddr *sap = (struct sockaddr *)&ctx->nfs_server.address;
int max_namelen = PAGE_SIZE;
int max_pathlen = NFS_MAXPATHLEN;
- struct sockaddr *sap = (struct sockaddr *)&ctx->nfs_server.address;
+ int port = 0;
+ int ret;

- if (nfs_parse_mount_options((char *)options, ctx) == 0)
- return -EINVAL;
+ if (!fc->source)
+ goto out_no_device_name;
+
+ /* Check for sanity first. */
+ if (ctx->minorversion && ctx->version != 4)
+ goto out_minorversion_mismatch;
+
+ if (ctx->options & NFS_OPTION_MIGRATION &&
+ (ctx->version != 4 || ctx->minorversion != 0))
+ goto out_migration_misuse;
+
+ /* Verify that any proto=/mountproto= options match the address
+ * families in the addr=/mountaddr= options.
+ */
+ if (ctx->protofamily != AF_UNSPEC &&
+ ctx->protofamily != ctx->nfs_server.address.sa_family)
+ goto out_proto_mismatch;
+
+ if (ctx->mountfamily != AF_UNSPEC) {
+ if (ctx->mount_server.addrlen) {
+ if (ctx->mountfamily != ctx->mount_server.address.sa_family)
+ goto out_mountproto_mismatch;
+ } else {
+ if (ctx->mountfamily != ctx->nfs_server.address.sa_family)
+ goto out_mountproto_mismatch;
+ }
+ }

if (!nfs_verify_server_address(sap))
goto out_no_address;
@@ -1320,8 +1273,24 @@ int nfs_validate_text_mount_data(void *options,

nfs_set_port(sap, &ctx->nfs_server.port, port);

- return nfs_parse_devname(ctx, dev_name, max_namelen, max_pathlen);
+ ret = nfs_parse_devname(ctx, fc->source, max_namelen, max_pathlen);
+ if (ret < 0)
+ return ret;
+
+ /* Load the NFS protocol module if we haven't done so yet */
+ if (!ctx->mount_info.nfs_mod) {
+ nfs_mod = get_nfs_version(ctx->version);
+ if (IS_ERR(nfs_mod)) {
+ ret = PTR_ERR(nfs_mod);
+ goto out_version_unavailable;
+ }
+ ctx->mount_info.nfs_mod = nfs_mod;
+ }
+ return 0;

+out_no_device_name:
+ dfprintk(MOUNT, "NFS: Device name not specified\n");
+ return -EINVAL;
#if !IS_ENABLED(CONFIG_NFS_V4)
out_v4_not_compiled:
dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
@@ -1331,8 +1300,201 @@ int nfs_validate_text_mount_data(void *options,
dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
return -EINVAL;
#endif /* !CONFIG_NFS_V4 */
-
out_no_address:
dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
return -EINVAL;
+out_mountproto_mismatch:
+ dfprintk(MOUNT, "NFS: Mount server address does not match mountproto= option\n");
+ return -EINVAL;
+out_proto_mismatch:
+ dfprintk(MOUNT, "NFS: Server address does not match proto= option\n");
+ return -EINVAL;
+out_minorversion_mismatch:
+ dfprintk(MOUNT, "NFS: Mount option vers=%u does not support minorversion=%u\n",
+ ctx->version, ctx->minorversion);
+ return -EINVAL;
+out_migration_misuse:
+ dfprintk(MOUNT, "NFS: 'Migration' not supported for this NFS version\n");
+ return -EINVAL;
+out_version_unavailable:
+ dfprintk(MOUNT, "NFS: Version unavailable\n");
+ return ret;
+}
+
+/*
+ * Create an NFS superblock by the appropriate method.
+ */
+static int nfs_get_tree(struct fs_context *fc)
+{
+ struct nfs_fs_context *ctx = nfs_fc2context(fc);
+ int err = nfs_fs_context_validate(fc);
+
+ if (err)
+ return err;
+ if (!ctx->internal)
+ return ctx->mount_info.nfs_mod->rpc_ops->try_get_tree(fc);
+ else
+ return nfs_get_tree_common(fc);
}
+
+/*
+ * Handle duplication of a configuration. The caller copied *src into *sc, but
+ * it can't deal with resource pointers in the filesystem context, so we have
+ * to do that. We need to clear pointers, copy data or get extra refs as
+ * appropriate.
+ */
+static int nfs_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc)
+{
+ struct nfs_fs_context *src = nfs_fc2context(src_fc), *ctx;
+
+ ctx = kmemdup(src, sizeof(struct nfs_fs_context), GFP_KERNEL);
+ if (!ctx)
+ return -ENOMEM;
+
+ ctx->mount_info.mntfh = nfs_alloc_fhandle();
+ if (!ctx->mount_info.mntfh) {
+ kfree(ctx);
+ return -ENOMEM;
+ }
+ nfs_copy_fh(ctx->mount_info.mntfh, src->mount_info.mntfh);
+
+ __module_get(ctx->mount_info.nfs_mod->owner);
+ ctx->client_address = NULL;
+ ctx->mount_server.hostname = NULL;
+ ctx->nfs_server.export_path = NULL;
+ ctx->nfs_server.hostname = NULL;
+ ctx->fscache_uniq = NULL;
+ ctx->clone_data.addr = NULL;
+ ctx->clone_data.fattr = NULL;
+ fc->fs_private = ctx;
+ return 0;
+}
+
+static void nfs_fs_context_free(struct fs_context *fc)
+{
+ struct nfs_fs_context *ctx = nfs_fc2context(fc);
+
+ if (ctx) {
+ if (ctx->mount_info.server)
+ nfs_free_server(ctx->mount_info.server);
+ if (ctx->mount_info.nfs_mod)
+ put_nfs_version(ctx->mount_info.nfs_mod);
+ kfree(ctx->client_address);
+ kfree(ctx->mount_server.hostname);
+ kfree(ctx->nfs_server.export_path);
+ kfree(ctx->nfs_server.hostname);
+ kfree(ctx->fscache_uniq);
+ nfs_free_fhandle(ctx->mount_info.mntfh);
+ kfree(ctx->clone_data.addr);
+ nfs_free_fattr(ctx->clone_data.fattr);
+ kfree(ctx);
+ }
+}
+
+static const struct fs_context_operations nfs_fs_context_ops = {
+ .free = nfs_fs_context_free,
+ .dup = nfs_fs_context_dup,
+ .parse_param = nfs_fs_context_parse_param,
+ .parse_monolithic = nfs_fs_context_parse_monolithic,
+ .get_tree = nfs_get_tree,
+ .reconfigure = nfs_reconfigure,
+};
+
+/*
+ * Prepare superblock configuration. We use the namespaces attached to the
+ * context. This may be the current process's namespaces, or it may be a
+ * container's namespaces.
+ */
+static int nfs_init_fs_context(struct fs_context *fc)
+{
+ struct nfs_fs_context *ctx;
+
+ ctx = kzalloc(sizeof(struct nfs_fs_context), GFP_KERNEL);
+ if (unlikely(!ctx))
+ return -ENOMEM;
+
+ ctx->mount_info.ctx = ctx;
+ ctx->mount_info.mntfh = nfs_alloc_fhandle();
+ if (unlikely(!ctx->mount_info.mntfh)) {
+ kfree(ctx);
+ return -ENOMEM;
+ }
+
+ ctx->protofamily = AF_UNSPEC;
+ ctx->mountfamily = AF_UNSPEC;
+ ctx->mount_server.port = NFS_UNSPEC_PORT;
+
+ if (fc->root) {
+ /* reconfigure, start with the current config */
+ struct nfs_server *nfss = fc->root->d_sb->s_fs_info;
+ struct net *net = nfss->nfs_client->cl_net;
+
+ ctx->flags = nfss->flags;
+ ctx->rsize = nfss->rsize;
+ ctx->wsize = nfss->wsize;
+ ctx->retrans = nfss->client->cl_timeout->to_retries;
+ ctx->selected_flavor = nfss->client->cl_auth->au_flavor;
+ ctx->acregmin = nfss->acregmin / HZ;
+ ctx->acregmax = nfss->acregmax / HZ;
+ ctx->acdirmin = nfss->acdirmin / HZ;
+ ctx->acdirmax = nfss->acdirmax / HZ;
+ ctx->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
+ ctx->nfs_server.port = nfss->port;
+ ctx->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
+ ctx->version = nfss->nfs_client->rpc_ops->version;
+ ctx->minorversion = nfss->nfs_client->cl_minorversion;
+
+ memcpy(&ctx->nfs_server.address, &nfss->nfs_client->cl_addr,
+ ctx->nfs_server.addrlen);
+
+ if (fc->net_ns != net) {
+ put_net(fc->net_ns);
+ fc->net_ns = get_net(net);
+ }
+
+ ctx->mount_info.nfs_mod = nfss->nfs_client->cl_nfs_mod;
+ __module_get(ctx->mount_info.nfs_mod->owner);
+ } else {
+ /* defaults */
+ ctx->timeo = NFS_UNSPEC_TIMEO;
+ ctx->retrans = NFS_UNSPEC_RETRANS;
+ ctx->acregmin = NFS_DEF_ACREGMIN;
+ ctx->acregmax = NFS_DEF_ACREGMAX;
+ ctx->acdirmin = NFS_DEF_ACDIRMIN;
+ ctx->acdirmax = NFS_DEF_ACDIRMAX;
+ ctx->nfs_server.port = NFS_UNSPEC_PORT;
+ ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
+ ctx->selected_flavor = RPC_AUTH_MAXFLAVOR;
+ ctx->minorversion = 0;
+ ctx->need_mount = true;
+ }
+ ctx->net = fc->net_ns;
+ fc->fs_private = ctx;
+ fc->ops = &nfs_fs_context_ops;
+ return 0;
+}
+
+struct file_system_type nfs_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "nfs",
+ .init_fs_context = nfs_init_fs_context,
+ .parameters = &nfs_fs_parameters,
+ .kill_sb = nfs_kill_super,
+ .fs_flags = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
+};
+MODULE_ALIAS_FS("nfs");
+EXPORT_SYMBOL_GPL(nfs_fs_type);
+
+#if IS_ENABLED(CONFIG_NFS_V4)
+struct file_system_type nfs4_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "nfs4",
+ .init_fs_context = nfs_init_fs_context,
+ .parameters = &nfs_fs_parameters,
+ .kill_sb = nfs_kill_super,
+ .fs_flags = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
+};
+MODULE_ALIAS_FS("nfs4");
+MODULE_ALIAS("nfs4");
+EXPORT_SYMBOL_GPL(nfs4_fs_type);
+#endif /* CONFIG_NFS_V4 */
diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 003c2b8eb1e6..1cd09df9e0b5 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -4,7 +4,7 @@
*/

#include "nfs4_fs.h"
-#include <linux/mount.h>
+#include <linux/fs_context.h>
#include <linux/security.h>
#include <linux/crc32.h>
#include <linux/sunrpc/addr.h>
@@ -16,6 +16,7 @@
extern const struct export_operations nfs_export_ops;

struct nfs_string;
+struct nfs_pageio_descriptor;

static inline void nfs_attr_check_mountpoint(struct super_block *parent, struct nfs_fattr *fattr)
{
@@ -34,12 +35,13 @@ static inline int nfs_attr_use_mounted_on_fileid(struct nfs_fattr *fattr)

struct nfs_clone_mount {
const struct super_block *sb;
- const struct dentry *dentry;
+ struct dentry *dentry;
char *hostname;
char *mnt_path;
struct sockaddr *addr;
size_t addrlen;
rpc_authflavor_t authflavor;
+ struct nfs_fattr *fattr;
};

/*
@@ -78,10 +80,23 @@ struct nfs_client_initdata {
const struct cred *cred;
};

+struct nfs_mount_info {
+ unsigned int inherited_bsize;
+ struct nfs_fs_context *ctx;
+ struct nfs_clone_mount *cloned;
+ struct nfs_server *server;
+ struct nfs_fh *mntfh;
+ struct nfs_subversion *nfs_mod;
+};
+
/*
* In-kernel mount arguments
*/
struct nfs_fs_context {
+ bool internal;
+ bool skip_reconfig_option_check;
+ bool need_mount;
+ bool sloppy;
unsigned int flags; /* NFS{,4}_MOUNT_* flags */
unsigned int rsize, wsize;
unsigned int timeo, retrans;
@@ -98,8 +113,6 @@ struct nfs_fs_context {
char *fscache_uniq;
unsigned short protofamily;
unsigned short mountfamily;
- bool need_mount;
- bool sloppy;

struct {
union {
@@ -124,14 +137,23 @@ struct nfs_fs_context {
int port;
unsigned short protocol;
unsigned short nconnect;
+ unsigned short export_path_len;
} nfs_server;

void *lsm_opts;
struct net *net;

char buf[32]; /* Parse buffer */
+
+ struct nfs_mount_info mount_info;
+ struct nfs_clone_mount clone_data;
};

+static inline struct nfs_fs_context *nfs_fc2context(const struct fs_context *fc)
+{
+ return fc->fs_private;
+}
+
/* mount_clnt.c */
struct nfs_mount_request {
struct sockaddr *sap;
@@ -147,15 +169,6 @@ struct nfs_mount_request {
struct net *net;
};

-struct nfs_mount_info {
- unsigned int inherited_bsize;
- struct nfs_fs_context *ctx;
- struct nfs_clone_mount *cloned;
- struct nfs_server *server;
- struct nfs_fh *mntfh;
- struct nfs_subversion *nfs_mod;
-};
-
extern int nfs_mount(struct nfs_mount_request *info);
extern void nfs_umount(const struct nfs_mount_request *info);

@@ -235,22 +248,8 @@ static inline void nfs_fs_proc_exit(void)
extern const struct svc_version nfs4_callback_version1;
extern const struct svc_version nfs4_callback_version4;

-struct nfs_pageio_descriptor;
-
-/* mount.c */
-#define NFS_TEXT_DATA 1
-
-extern struct nfs_fs_context *nfs_alloc_parsed_mount_data(void);
-extern void nfs_free_parsed_mount_data(struct nfs_fs_context *ctx);
-extern int nfs_parse_mount_options(char *raw, struct nfs_fs_context *ctx);
-extern int nfs_validate_mount_data(struct file_system_type *fs_type,
- void *options,
- struct nfs_fs_context *ctx,
- struct nfs_fh *mntfh,
- const char *dev_name);
-extern int nfs_validate_text_mount_data(void *options,
- struct nfs_fs_context *ctx,
- const char *dev_name);
+/* fs_context.c */
+extern struct file_system_type nfs_fs_type;

/* pagelist.c */
extern int __init nfs_init_nfspagecache(void);
@@ -411,14 +410,9 @@ extern int nfs_wait_atomic_killable(atomic_t *p, unsigned int mode);

/* super.c */
extern const struct super_operations nfs_sops;
-extern struct file_system_type nfs_fs_type;
-extern struct file_system_type nfs_prepared_fs_type;
-#if IS_ENABLED(CONFIG_NFS_V4)
-extern struct file_system_type nfs4_referral_fs_type;
-#endif
bool nfs_auth_info_match(const struct nfs_auth_info *, rpc_authflavor_t);
-struct dentry *nfs_try_mount(int, const char *, struct nfs_mount_info *);
-struct dentry *nfs_fs_mount(struct file_system_type *, int, const char *, void *);
+int nfs_try_get_tree(struct fs_context *);
+int nfs_get_tree_common(struct fs_context *);
void nfs_kill_super(struct super_block *);

extern struct rpc_stat nfs_rpcstat;
@@ -446,10 +440,8 @@ static inline bool nfs_file_io_is_buffered(struct nfs_inode *nfsi)
extern char *nfs_path(char **p, struct dentry *dentry,
char *buffer, ssize_t buflen, unsigned flags);
extern struct vfsmount *nfs_d_automount(struct path *path);
-struct vfsmount *nfs_submount(struct nfs_server *, struct dentry *,
- struct nfs_fh *, struct nfs_fattr *);
-struct vfsmount *nfs_do_submount(struct dentry *, struct nfs_fh *,
- struct nfs_fattr *, rpc_authflavor_t);
+int nfs_submount(struct fs_context *, struct nfs_server *);
+int nfs_do_submount(struct fs_context *);

/* getroot.c */
extern struct dentry *nfs_get_root(struct super_block *, struct nfs_fh *,
@@ -476,7 +468,7 @@ int nfs_show_options(struct seq_file *, struct dentry *);
int nfs_show_devname(struct seq_file *, struct dentry *);
int nfs_show_path(struct seq_file *, struct dentry *);
int nfs_show_stats(struct seq_file *, struct dentry *);
-int nfs_remount(struct super_block *sb, int *flags, char *raw_data);
+int nfs_reconfigure(struct fs_context *);

/* write.c */
extern void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio,
diff --git a/fs/nfs/namespace.c b/fs/nfs/namespace.c
index bfe607374feb..9b344fcd23b0 100644
--- a/fs/nfs/namespace.c
+++ b/fs/nfs/namespace.c
@@ -140,34 +140,65 @@ EXPORT_SYMBOL_GPL(nfs_path);
*/
struct vfsmount *nfs_d_automount(struct path *path)
{
- struct vfsmount *mnt;
+ struct nfs_fs_context *ctx;
+ struct fs_context *fc;
+ struct vfsmount *mnt = ERR_PTR(-ENOMEM);
struct nfs_server *server = NFS_SERVER(d_inode(path->dentry));
- struct nfs_fh *fh = NULL;
- struct nfs_fattr *fattr = NULL;
+ struct nfs_client *client = server->nfs_client;
+ int ret;

if (IS_ROOT(path->dentry))
return ERR_PTR(-ESTALE);

- mnt = ERR_PTR(-ENOMEM);
- fh = nfs_alloc_fhandle();
- fattr = nfs_alloc_fattr();
- if (fh == NULL || fattr == NULL)
- goto out;
+ /* Open a new filesystem context, transferring parameters from the
+ * parent superblock, including the network namespace.
+ */
+ fc = fs_context_for_submount(&nfs_fs_type, path->dentry);
+ if (IS_ERR(fc))
+ return ERR_CAST(fc);

- mnt = server->nfs_client->rpc_ops->submount(server, path->dentry, fh, fattr);
+ ctx = nfs_fc2context(fc);
+ ctx->clone_data.dentry = path->dentry;
+ ctx->clone_data.sb = path->dentry->d_sb;
+ ctx->clone_data.fattr = nfs_alloc_fattr();
+ if (!ctx->clone_data.fattr)
+ goto out_fc;
+
+ if (fc->net_ns != client->cl_net) {
+ put_net(fc->net_ns);
+ fc->net_ns = get_net(client->cl_net);
+ }
+
+ /* for submounts we want the same server; referrals will reassign */
+ memcpy(&ctx->nfs_server.address, &client->cl_addr, client->cl_addrlen);
+ ctx->nfs_server.addrlen = client->cl_addrlen;
+ ctx->nfs_server.port = server->port;
+
+ ctx->version = client->rpc_ops->version;
+ ctx->minorversion = client->cl_minorversion;
+ ctx->mount_info.nfs_mod = client->cl_nfs_mod;
+ __module_get(ctx->mount_info.nfs_mod->owner);
+
+ ret = client->rpc_ops->submount(fc, server);
+ if (ret < 0) {
+ mnt = ERR_PTR(ret);
+ goto out_fc;
+ }
+
+ up_write(&fc->root->d_sb->s_umount);
+ mnt = vfs_create_mount(fc);
if (IS_ERR(mnt))
- goto out;
+ goto out_fc;

if (nfs_mountpoint_expiry_timeout < 0)
- goto out;
+ goto out_fc;

mntget(mnt); /* prevent immediate expiration */
mnt_set_expiry(mnt, &nfs_automount_list);
schedule_delayed_work(&nfs_automount_task, nfs_mountpoint_expiry_timeout);

-out:
- nfs_free_fattr(fattr);
- nfs_free_fhandle(fh);
+out_fc:
+ put_fs_context(fc);
return mnt;
}

@@ -222,61 +253,62 @@ void nfs_release_automount_timer(void)
* @authflavor: security flavor to use when performing the mount
*
*/
-struct vfsmount *nfs_do_submount(struct dentry *dentry, struct nfs_fh *fh,
- struct nfs_fattr *fattr, rpc_authflavor_t authflavor)
+int nfs_do_submount(struct fs_context *fc)
{
- struct super_block *sb = dentry->d_sb;
- struct nfs_clone_mount mountdata = {
- .sb = sb,
- .dentry = dentry,
- .authflavor = authflavor,
- };
- struct nfs_mount_info mount_info = {
- .inherited_bsize = sb->s_blocksize_bits,
- .cloned = &mountdata,
- .mntfh = fh,
- .nfs_mod = NFS_SB(sb)->nfs_client->cl_nfs_mod,
- };
+ struct nfs_fs_context *ctx = nfs_fc2context(fc);
+ struct dentry *dentry = ctx->clone_data.dentry;
struct nfs_server *server;
- struct vfsmount *mnt;
- char *page = (char *) __get_free_page(GFP_USER);
- char *devname;
+ char *buffer, *p;
+ int ret;

- if (page == NULL)
- return ERR_PTR(-ENOMEM);
+ /* create a new volume representation */
+ server = ctx->mount_info.nfs_mod->rpc_ops->clone_server(NFS_SB(ctx->clone_data.sb),
+ ctx->mount_info.mntfh,
+ ctx->clone_data.fattr,
+ ctx->selected_flavor);

- server = mount_info.nfs_mod->rpc_ops->clone_server(NFS_SB(sb), fh,
- fattr, authflavor);
if (IS_ERR(server))
- return ERR_CAST(server);
+ return PTR_ERR(server);

- mount_info.server = server;
+ ctx->mount_info.server = server;

- devname = nfs_devname(dentry, page, PAGE_SIZE);
- if (IS_ERR(devname))
- mnt = ERR_CAST(devname);
- else
- mnt = vfs_submount(dentry, &nfs_prepared_fs_type, devname, &mount_info);
+ buffer = kmalloc(4096, GFP_USER);
+ if (!buffer)
+ return -ENOMEM;

- if (mount_info.server)
- nfs_free_server(mount_info.server);
- free_page((unsigned long)page);
- return mnt;
+ ctx->internal = true;
+ ctx->mount_info.inherited_bsize = ctx->clone_data.sb->s_blocksize_bits;
+
+ p = nfs_devname(dentry, buffer, 4096);
+ if (IS_ERR(p)) {
+ dprintk("NFS: Couldn't determine submount pathname\n");
+ ret = PTR_ERR(p);
+ } else {
+ ret = vfs_parse_fs_string(fc, "source", p, buffer + 4096 - p);
+ if (!ret)
+ ret = vfs_get_tree(fc);
+ }
+ kfree(buffer);
+ return ret;
}
EXPORT_SYMBOL_GPL(nfs_do_submount);

-struct vfsmount *nfs_submount(struct nfs_server *server, struct dentry *dentry,
- struct nfs_fh *fh, struct nfs_fattr *fattr)
+int nfs_submount(struct fs_context *fc, struct nfs_server *server)
{
- int err;
+ struct nfs_fs_context *ctx = nfs_fc2context(fc);
+ struct dentry *dentry = ctx->clone_data.dentry;
struct dentry *parent = dget_parent(dentry);
+ int err;

/* Look it up again to get its attributes */
- err = server->nfs_client->rpc_ops->lookup(d_inode(parent), &dentry->d_name, fh, fattr, NULL);
+ err = server->nfs_client->rpc_ops->lookup(d_inode(parent), &dentry->d_name,
+ ctx->mount_info.mntfh, ctx->clone_data.fattr,
+ NULL);
dput(parent);
if (err != 0)
- return ERR_PTR(err);
+ return err;

- return nfs_do_submount(dentry, fh, fattr, server->client->cl_auth->au_flavor);
+ ctx->selected_flavor = server->client->cl_auth->au_flavor;
+ return nfs_do_submount(fc);
}
EXPORT_SYMBOL_GPL(nfs_submount);
diff --git a/fs/nfs/nfs3proc.c b/fs/nfs/nfs3proc.c
index 9eb2f1a503ab..657041c3a03f 100644
--- a/fs/nfs/nfs3proc.c
+++ b/fs/nfs/nfs3proc.c
@@ -990,7 +990,7 @@ const struct nfs_rpc_ops nfs_v3_clientops = {
.nlmclnt_ops = &nlmclnt_fl_close_lock_ops,
.getroot = nfs3_proc_get_root,
.submount = nfs_submount,
- .try_mount = nfs_try_mount,
+ .try_get_tree = nfs_try_get_tree,
.getattr = nfs3_proc_getattr,
.setattr = nfs3_proc_setattr,
.lookup = nfs3_proc_lookup,
diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
index 5d539dce9cef..9c136d53987d 100644
--- a/fs/nfs/nfs4_fs.h
+++ b/fs/nfs/nfs4_fs.h
@@ -268,14 +268,13 @@ extern const struct dentry_operations nfs4_dentry_operations;
int nfs_atomic_open(struct inode *, struct dentry *, struct file *,
unsigned, umode_t);

-/* super.c */
+/* fs_context.c */
extern struct file_system_type nfs4_fs_type;

/* nfs4namespace.c */
struct rpc_clnt *nfs4_negotiate_security(struct rpc_clnt *, struct inode *,
const struct qstr *);
-struct vfsmount *nfs4_submount(struct nfs_server *, struct dentry *,
- struct nfs_fh *, struct nfs_fattr *);
+int nfs4_submount(struct fs_context *, struct nfs_server *);
int nfs4_replace_transport(struct nfs_server *server,
const struct nfs4_fs_locations *locations);

@@ -526,7 +525,6 @@ extern const nfs4_stateid invalid_stateid;
/* nfs4super.c */
struct nfs_mount_info;
extern struct nfs_subversion nfs_v4;
-struct dentry *nfs4_try_mount(int, const char *, struct nfs_mount_info *);
extern bool nfs4_disable_idmapping;
extern unsigned short max_session_slots;
extern unsigned short max_session_cb_slots;
@@ -536,6 +534,9 @@ extern bool recover_lost_locks;
#define NFS4_CLIENT_ID_UNIQ_LEN (64)
extern char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN];

+extern int nfs4_try_get_tree(struct fs_context *);
+extern int nfs4_get_referral_tree(struct fs_context *);
+
/* nfs4sysctl.c */
#ifdef CONFIG_SYSCTL
int nfs4_register_sysctl(void);
diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c
index 620de905cba9..be4eb720d5b6 100644
--- a/fs/nfs/nfs4file.c
+++ b/fs/nfs/nfs4file.c
@@ -7,6 +7,7 @@
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/falloc.h>
+#include <linux/mount.h>
#include <linux/nfs_fs.h>
#include "delegation.h"
#include "internal.h"
diff --git a/fs/nfs/nfs4namespace.c b/fs/nfs/nfs4namespace.c
index 2e460c33ae48..a1a0c4c53ce1 100644
--- a/fs/nfs/nfs4namespace.c
+++ b/fs/nfs/nfs4namespace.c
@@ -8,6 +8,7 @@
* NFSv4 namespace
*/

+#include <linux/module.h>
#include <linux/dcache.h>
#include <linux/mount.h>
#include <linux/namei.h>
@@ -21,37 +22,64 @@
#include <linux/inet.h>
#include "internal.h"
#include "nfs4_fs.h"
+#include "nfs.h"
#include "dns_resolve.h"

#define NFSDBG_FACILITY NFSDBG_VFS

+/*
+ * Work out the length that an NFSv4 path would render to as a standard posix
+ * path, with a leading slash but no terminating slash.
+ */
+static ssize_t nfs4_pathname_len(const struct nfs4_pathname *pathname)
+{
+ ssize_t len = 0;
+ int i;
+
+ for (i = 0; i < pathname->ncomponents; i++) {
+ const struct nfs4_string *component = &pathname->components[i];
+
+ if (component->len > NAME_MAX)
+ goto too_long;
+ len += 1 + component->len; /* Adding "/foo" */
+ if (len > PATH_MAX)
+ goto too_long;
+ }
+ return len;
+
+too_long:
+ return -ENAMETOOLONG;
+}
+
/*
* Convert the NFSv4 pathname components into a standard posix path.
- *
- * Note that the resulting string will be placed at the end of the buffer
*/
-static inline char *nfs4_pathname_string(const struct nfs4_pathname *pathname,
- char *buffer, ssize_t buflen)
+static char *nfs4_pathname_string(const struct nfs4_pathname *pathname,
+ unsigned short *_len)
{
- char *end = buffer + buflen;
- int n;
+ ssize_t len;
+ char *buf, *p;
+ int i;
+
+ len = nfs4_pathname_len(pathname);
+ if (len < 0)
+ return ERR_PTR(len);
+ *_len = len;
+
+ p = buf = kmalloc(len + 1, GFP_KERNEL);
+ if (!buf)
+ return ERR_PTR(-ENOMEM);
+
+ for (i = 0; i < pathname->ncomponents; i++) {
+ const struct nfs4_string *component = &pathname->components[i];

- *--end = '\0';
- buflen--;
-
- n = pathname->ncomponents;
- while (--n >= 0) {
- const struct nfs4_string *component = &pathname->components[n];
- buflen -= component->len + 1;
- if (buflen < 0)
- goto Elong;
- end -= component->len;
- memcpy(end, component->data, component->len);
- *--end = '/';
+ *p++ = '/';
+ memcpy(p, component->data, component->len);
+ p += component->len;
}
- return end;
-Elong:
- return ERR_PTR(-ENAMETOOLONG);
+
+ *p = 0;
+ return buf;
}

/*
@@ -100,21 +128,32 @@ static char *nfs4_path(struct dentry *dentry, char *buffer, ssize_t buflen)
*/
static int nfs4_validate_fspath(struct dentry *dentry,
const struct nfs4_fs_locations *locations,
- char *page, char *page2)
+ struct nfs_fs_context *ctx)
{
const char *path, *fs_path;
+ char *buf;
+ unsigned short len;
+ int n;

- path = nfs4_path(dentry, page, PAGE_SIZE);
- if (IS_ERR(path))
+ buf = kmalloc(4096, GFP_KERNEL);
+ path = nfs4_path(dentry, buf, 4096);
+ if (IS_ERR(path)) {
+ kfree(buf);
return PTR_ERR(path);
+ }

- fs_path = nfs4_pathname_string(&locations->fs_path, page2, PAGE_SIZE);
- if (IS_ERR(fs_path))
+ fs_path = nfs4_pathname_string(&locations->fs_path, &len);
+ if (IS_ERR(fs_path)) {
+ kfree(buf);
return PTR_ERR(fs_path);
+ }

- if (strncmp(path, fs_path, strlen(fs_path)) != 0) {
+ n = strncmp(path, fs_path, len);
+ kfree(buf);
+ kfree(fs_path);
+ if (n != 0) {
dprintk("%s: path %s does not begin with fsroot %s\n",
- __func__, path, fs_path);
+ __func__, path, ctx->nfs_server.export_path);
return -ENOENT;
}

@@ -236,55 +275,83 @@ nfs4_negotiate_security(struct rpc_clnt *clnt, struct inode *inode,
return new;
}

-static struct vfsmount *try_location(struct nfs_clone_mount *mountdata,
- char *page, char *page2,
- const struct nfs4_fs_location *location)
+static int try_location(struct fs_context *fc,
+ const struct nfs4_fs_location *location)
{
const size_t addr_bufsize = sizeof(struct sockaddr_storage);
- struct net *net = rpc_net_ns(NFS_SB(mountdata->sb)->client);
- struct vfsmount *mnt = ERR_PTR(-ENOENT);
- char *mnt_path;
- unsigned int maxbuflen;
- unsigned int s;
+ struct nfs_fs_context *ctx = nfs_fc2context(fc);
+ unsigned int len, s;
+ char *export_path, *source, *p;
+ int ret = -ENOENT;
+
+ /* Allocate a buffer big enough to hold any of the hostnames plus a
+ * terminating char and also a buffer big enough to hold the hostname
+ * plus a colon plus the path.
+ */
+ len = 0;
+ for (s = 0; s < location->nservers; s++) {
+ const struct nfs4_string *buf = &location->servers[s];
+ if (buf->len > len)
+ len = buf->len;
+ }

- mnt_path = nfs4_pathname_string(&location->rootpath, page2, PAGE_SIZE);
- if (IS_ERR(mnt_path))
- return ERR_CAST(mnt_path);
- mountdata->mnt_path = mnt_path;
- maxbuflen = mnt_path - 1 - page2;
+ kfree(ctx->nfs_server.hostname);
+ ctx->nfs_server.hostname = kmalloc(len + 1, GFP_KERNEL);
+ if (!ctx->nfs_server.hostname)
+ return -ENOMEM;

- mountdata->addr = kmalloc(addr_bufsize, GFP_KERNEL);
- if (mountdata->addr == NULL)
- return ERR_PTR(-ENOMEM);
+ export_path = nfs4_pathname_string(&location->rootpath,
+ &ctx->nfs_server.export_path_len);
+ if (IS_ERR(export_path))
+ return PTR_ERR(export_path);

+ ctx->nfs_server.export_path = export_path;
+
+ source = kmalloc(len + 1 + ctx->nfs_server.export_path_len + 1,
+ GFP_KERNEL);
+ if (!source)
+ return -ENOMEM;
+
+ kfree(fc->source);
+ fc->source = source;
+
+ ctx->clone_data.addr = kmalloc(addr_bufsize, GFP_KERNEL);
+ if (ctx->clone_data.addr == NULL)
+ return -ENOMEM;
for (s = 0; s < location->nservers; s++) {
const struct nfs4_string *buf = &location->servers[s];

- if (buf->len <= 0 || buf->len >= maxbuflen)
- continue;
-
if (memchr(buf->data, IPV6_SCOPE_DELIMITER, buf->len))
continue;

- mountdata->addrlen = nfs_parse_server_name(buf->data, buf->len,
- mountdata->addr, addr_bufsize, net);
- if (mountdata->addrlen == 0)
+ ctx->clone_data.addrlen =
+ nfs_parse_server_name(buf->data, buf->len,
+ ctx->clone_data.addr,
+ addr_bufsize,
+ fc->net_ns);
+ if (ctx->clone_data.addrlen == 0)
continue;

- memcpy(page2, buf->data, buf->len);
- page2[buf->len] = '\0';
- mountdata->hostname = page2;
+ rpc_set_port(ctx->clone_data.addr, NFS_PORT);

- snprintf(page, PAGE_SIZE, "%s:%s",
- mountdata->hostname,
- mountdata->mnt_path);
+ memcpy(ctx->nfs_server.hostname, buf->data, buf->len);
+ ctx->nfs_server.hostname[buf->len] = '\0';
+ ctx->clone_data.hostname = ctx->nfs_server.hostname;

- mnt = vfs_submount(mountdata->dentry, &nfs4_referral_fs_type, page, mountdata);
- if (!IS_ERR(mnt))
- break;
+ p = source;
+ memcpy(p, buf->data, buf->len);
+ p += buf->len;
+ *p++ = ':';
+ memcpy(p, ctx->nfs_server.export_path, ctx->nfs_server.export_path_len);
+ p += ctx->nfs_server.export_path_len;
+ *p = 0;
+
+ ret = nfs4_get_referral_tree(fc);
+ if (ret == 0)
+ return 0;
}
- kfree(mountdata->addr);
- return mnt;
+
+ return ret;
}

/**
@@ -293,38 +360,23 @@ static struct vfsmount *try_location(struct nfs_clone_mount *mountdata,
* @locations: array of NFSv4 server location information
*
*/
-static struct vfsmount *nfs_follow_referral(struct dentry *dentry,
- const struct nfs4_fs_locations *locations)
+static int nfs_follow_referral(struct fs_context *fc,
+ const struct nfs4_fs_locations *locations)
{
- struct vfsmount *mnt = ERR_PTR(-ENOENT);
- struct nfs_clone_mount mountdata = {
- .sb = dentry->d_sb,
- .dentry = dentry,
- .authflavor = NFS_SB(dentry->d_sb)->client->cl_auth->au_flavor,
- };
- char *page = NULL, *page2 = NULL;
+ struct nfs_fs_context *ctx = nfs_fc2context(fc);
int loc, error;

if (locations == NULL || locations->nlocations <= 0)
- goto out;
-
- dprintk("%s: referral at %pd2\n", __func__, dentry);
-
- page = (char *) __get_free_page(GFP_USER);
- if (!page)
- goto out;
+ return -ENOENT;

- page2 = (char *) __get_free_page(GFP_USER);
- if (!page2)
- goto out;
+ dprintk("%s: referral at %pd2\n", __func__, ctx->clone_data.dentry);

/* Ensure fs path is a prefix of current dentry path */
- error = nfs4_validate_fspath(dentry, locations, page, page2);
- if (error < 0) {
- mnt = ERR_PTR(error);
- goto out;
- }
+ error = nfs4_validate_fspath(ctx->clone_data.dentry, locations, ctx);
+ if (error < 0)
+ return error;

+ error = -ENOENT;
for (loc = 0; loc < locations->nlocations; loc++) {
const struct nfs4_fs_location *location = &locations->locations[loc];

@@ -332,15 +384,12 @@ static struct vfsmount *nfs_follow_referral(struct dentry *dentry,
location->rootpath.ncomponents == 0)
continue;

- mnt = try_location(&mountdata, page, page2, location);
- if (!IS_ERR(mnt))
- break;
+ error = try_location(fc, location);
+ if (error == 0)
+ return 0;
}

-out:
- free_page((unsigned long) page);
- free_page((unsigned long) page2);
- return mnt;
+ return error;
}

/*
@@ -348,71 +397,73 @@ static struct vfsmount *nfs_follow_referral(struct dentry *dentry,
* @dentry - dentry of referral
*
*/
-static struct vfsmount *nfs_do_refmount(struct rpc_clnt *client, struct dentry *dentry)
+static int nfs_do_refmount(struct fs_context *fc, struct rpc_clnt *client)
{
- struct vfsmount *mnt = ERR_PTR(-ENOMEM);
- struct dentry *parent;
+ struct nfs_fs_context *ctx = nfs_fc2context(fc);
+ struct dentry *dentry, *parent;
struct nfs4_fs_locations *fs_locations = NULL;
struct page *page;
- int err;
+ int err = -ENOMEM;

/* BUG_ON(IS_ROOT(dentry)); */
page = alloc_page(GFP_KERNEL);
- if (page == NULL)
- return mnt;
+ if (!page)
+ return -ENOMEM;

fs_locations = kmalloc(sizeof(struct nfs4_fs_locations), GFP_KERNEL);
- if (fs_locations == NULL)
+ if (!fs_locations)
goto out_free;

/* Get locations */
- mnt = ERR_PTR(-ENOENT);
-
+ dentry = ctx->clone_data.dentry;
parent = dget_parent(dentry);
dprintk("%s: getting locations for %pd2\n",
__func__, dentry);

err = nfs4_proc_fs_locations(client, d_inode(parent), &dentry->d_name, fs_locations, page);
dput(parent);
- if (err != 0 ||
- fs_locations->nlocations <= 0 ||
+ if (err != 0)
+ goto out_free_2;
+
+ err = -ENOENT;
+ if (fs_locations->nlocations <= 0 ||
fs_locations->fs_path.ncomponents <= 0)
- goto out_free;
+ goto out_free_2;

- mnt = nfs_follow_referral(dentry, fs_locations);
+ err = nfs_follow_referral(fc, fs_locations);
+out_free_2:
+ kfree(fs_locations);
out_free:
__free_page(page);
- kfree(fs_locations);
- return mnt;
+ return err;
}

-struct vfsmount *nfs4_submount(struct nfs_server *server, struct dentry *dentry,
- struct nfs_fh *fh, struct nfs_fattr *fattr)
+int nfs4_submount(struct fs_context *fc, struct nfs_server *server)
{
- rpc_authflavor_t flavor = server->client->cl_auth->au_flavor;
+ struct nfs_fs_context *ctx = nfs_fc2context(fc);
+ struct dentry *dentry = ctx->clone_data.dentry;
struct dentry *parent = dget_parent(dentry);
struct inode *dir = d_inode(parent);
const struct qstr *name = &dentry->d_name;
struct rpc_clnt *client;
- struct vfsmount *mnt;
+ int ret;

/* Look it up again to get its attributes and sec flavor */
- client = nfs4_proc_lookup_mountpoint(dir, name, fh, fattr);
+ client = nfs4_proc_lookup_mountpoint(dir, name, ctx->mount_info.mntfh,
+ ctx->clone_data.fattr);
dput(parent);
if (IS_ERR(client))
- return ERR_CAST(client);
+ return PTR_ERR(client);

- if (fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL) {
- mnt = nfs_do_refmount(client, dentry);
- goto out;
+ ctx->selected_flavor = client->cl_auth->au_flavor;
+ if (ctx->clone_data.fattr->valid & NFS_ATTR_FATTR_V4_REFERRAL) {
+ ret = nfs_do_refmount(fc, client);
+ } else {
+ ret = nfs_do_submount(fc);
}

- if (client->cl_auth->au_flavor != flavor)
- flavor = client->cl_auth->au_flavor;
- mnt = nfs_do_submount(dentry, fh, fattr, flavor);
-out:
rpc_shutdown_client(client);
- return mnt;
+ return ret;
}

/*
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 76d37161409a..5f51f62b0652 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -10001,7 +10001,7 @@ const struct nfs_rpc_ops nfs_v4_clientops = {
.file_ops = &nfs4_file_operations,
.getroot = nfs4_proc_get_root,
.submount = nfs4_submount,
- .try_mount = nfs4_try_mount,
+ .try_get_tree = nfs4_try_get_tree,
.getattr = nfs4_proc_getattr,
.setattr = nfs4_proc_setattr,
.lookup = nfs4_proc_lookup,
diff --git a/fs/nfs/nfs4super.c b/fs/nfs/nfs4super.c
index f931e8f49b05..469726410c5c 100644
--- a/fs/nfs/nfs4super.c
+++ b/fs/nfs/nfs4super.c
@@ -4,6 +4,7 @@
*/
#include <linux/init.h>
#include <linux/module.h>
+#include <linux/mount.h>
#include <linux/nfs4_mount.h>
#include <linux/nfs_fs.h>
#include "delegation.h"
@@ -18,16 +19,6 @@

static int nfs4_write_inode(struct inode *inode, struct writeback_control *wbc);
static void nfs4_evict_inode(struct inode *inode);
-static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
- int flags, const char *dev_name, void *raw_data);
-
-struct file_system_type nfs4_referral_fs_type = {
- .owner = THIS_MODULE,
- .name = "nfs4",
- .mount = nfs4_referral_mount,
- .kill_sb = nfs_kill_super,
- .fs_flags = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
-};

static const struct super_operations nfs4_sops = {
.alloc_inode = nfs_alloc_inode,
@@ -41,7 +32,6 @@ static const struct super_operations nfs4_sops = {
.show_devname = nfs_show_devname,
.show_path = nfs_show_path,
.show_stats = nfs_show_stats,
- .remount_fs = nfs_remount,
};

struct nfs_subversion nfs_v4 = {
@@ -147,102 +137,121 @@ static void nfs_referral_loop_unprotect(void)
kfree(p);
}

-static struct dentry *do_nfs4_mount(struct nfs_server *server, int flags,
- struct nfs_mount_info *info,
- const char *hostname,
- const char *export_path)
+static int do_nfs4_mount(struct nfs_server *server,
+ struct fs_context *fc,
+ const char *hostname,
+ const char *export_path)
{
+ struct nfs_fs_context *root_ctx;
+ struct fs_context *root_fc;
struct vfsmount *root_mnt;
struct dentry *dentry;
- char *root_devname;
- int err;
size_t len;
+ int ret;
+
+ struct fs_parameter param = {
+ .key = "source",
+ .type = fs_value_is_string,
+ .dirfd = -1,
+ };

if (IS_ERR(server))
- return ERR_CAST(server);
+ return PTR_ERR(server);

- len = strlen(hostname) + 5;
- root_devname = kmalloc(len, GFP_KERNEL);
- if (root_devname == NULL) {
+ root_fc = vfs_dup_fs_context(fc);
+ if (IS_ERR(root_fc)) {
nfs_free_server(server);
- return ERR_PTR(-ENOMEM);
+ return PTR_ERR(root_fc);
+ }
+ kfree(root_fc->source);
+ root_fc->source = NULL;
+
+ root_ctx = nfs_fc2context(root_fc);
+ root_ctx->internal = true;
+ root_ctx->mount_info.server = server;
+ /* We leave export_path unset as it's not used to find the root. */
+
+ len = strlen(hostname) + 5;
+ param.string = kmalloc(len, GFP_KERNEL);
+ if (param.string == NULL) {
+ put_fs_context(root_fc);
+ return -ENOMEM;
}

/* Does hostname needs to be enclosed in brackets? */
if (strchr(hostname, ':'))
- snprintf(root_devname, len, "[%s]:/", hostname);
+ param.size = snprintf(param.string, len, "[%s]:/", hostname);
else
- snprintf(root_devname, len, "%s:/", hostname);
- info->server = server;
- root_mnt = vfs_kern_mount(&nfs_prepared_fs_type, flags, root_devname, info);
- if (info->server)
- nfs_free_server(info->server);
- info->server = NULL;
- kfree(root_devname);
+ param.size = snprintf(param.string, len, "%s:/", hostname);
+ ret = vfs_parse_fs_param(root_fc, &param);
+ kfree(param.string);
+ if (ret < 0) {
+ put_fs_context(root_fc);
+ return ret;
+ }
+ root_mnt = fc_mount(root_fc);
+ put_fs_context(root_fc);

if (IS_ERR(root_mnt))
- return ERR_CAST(root_mnt);
+ return PTR_ERR(root_mnt);

- err = nfs_referral_loop_protect();
- if (err) {
+ ret = nfs_referral_loop_protect();
+ if (ret) {
mntput(root_mnt);
- return ERR_PTR(err);
+ return ret;
}

dentry = mount_subtree(root_mnt, export_path);
nfs_referral_loop_unprotect();

- return dentry;
+ if (IS_ERR(dentry))
+ return PTR_ERR(dentry);
+
+ fc->root = dentry;
+ return 0;
}

-struct dentry *nfs4_try_mount(int flags, const char *dev_name,
- struct nfs_mount_info *mount_info)
+int nfs4_try_get_tree(struct fs_context *fc)
{
- struct nfs_fs_context *ctx = mount_info->ctx;
- struct dentry *res;
-
- dfprintk(MOUNT, "--> nfs4_try_mount()\n");
+ struct nfs_fs_context *ctx = nfs_fc2context(fc);
+ int err;

- res = do_nfs4_mount(nfs4_create_server(mount_info),
- flags, mount_info,
- ctx->nfs_server.hostname,
- ctx->nfs_server.export_path);
+ dfprintk(MOUNT, "--> nfs4_try_get_tree()\n");

- dfprintk(MOUNT, "<-- nfs4_try_mount() = %d%s\n",
- PTR_ERR_OR_ZERO(res),
- IS_ERR(res) ? " [error]" : "");
- return res;
+ /* We create a mount for the server's root, walk to the requested
+ * location and then create another mount for that.
+ */
+ err= do_nfs4_mount(nfs4_create_server(&ctx->mount_info),
+ fc, ctx->nfs_server.hostname,
+ ctx->nfs_server.export_path);
+ if (err) {
+ dfprintk(MOUNT, "<-- nfs4_try_get_tree() = %d [error]\n", err);
+ } else {
+ dfprintk(MOUNT, "<-- nfs4_try_get_tree() = 0\n");
+ }
+ return err;
}

/*
* Create an NFS4 server record on referral traversal
*/
-static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
- int flags, const char *dev_name, void *raw_data)
+int nfs4_get_referral_tree(struct fs_context *fc)
{
- struct nfs_clone_mount *data = raw_data;
- struct nfs_mount_info mount_info = {
- .cloned = data,
- .nfs_mod = &nfs_v4,
- };
- struct dentry *res;
+ struct nfs_fs_context *ctx = nfs_fc2context(fc);
+ int err;

dprintk("--> nfs4_referral_mount()\n");

- mount_info.mntfh = nfs_alloc_fhandle();
- if (!mount_info.mntfh)
- return ERR_PTR(-ENOMEM);
-
- res = do_nfs4_mount(nfs4_create_referral_server(mount_info.cloned,
- mount_info.mntfh),
- flags, &mount_info, data->hostname, data->mnt_path);
-
- dprintk("<-- nfs4_referral_mount() = %d%s\n",
- PTR_ERR_OR_ZERO(res),
- IS_ERR(res) ? " [error]" : "");
-
- nfs_free_fhandle(mount_info.mntfh);
- return res;
+ /* create a new volume representation */
+ err = do_nfs4_mount(nfs4_create_referral_server(&ctx->clone_data, ctx->mount_info.mntfh),
+ fc, ctx->nfs_server.hostname,
+ ctx->nfs_server.export_path);
+ if (err) {
+ dfprintk(MOUNT, "<-- nfs4_get_referral_tree() = %d [error]\n", err);
+ } else {
+ dfprintk(MOUNT, "<-- nfs4_get_referral_tree() = 0\n");
+ }
+ return err;
}


diff --git a/fs/nfs/proc.c b/fs/nfs/proc.c
index 0f7288b94633..44a15523bf40 100644
--- a/fs/nfs/proc.c
+++ b/fs/nfs/proc.c
@@ -710,7 +710,7 @@ const struct nfs_rpc_ops nfs_v2_clientops = {
.file_ops = &nfs_file_operations,
.getroot = nfs_proc_get_root,
.submount = nfs_submount,
- .try_mount = nfs_try_mount,
+ .try_get_tree = nfs_try_get_tree,
.getattr = nfs_proc_getattr,
.setattr = nfs_proc_setattr,
.lookup = nfs_proc_lookup,
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 6c9573a32a69..6ff99da978a8 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -70,28 +70,6 @@

#define NFSDBG_FACILITY NFSDBG_VFS

-static struct dentry *nfs_prepared_mount(struct file_system_type *fs_type,
- int flags, const char *dev_name, void *raw_data);
-
-struct file_system_type nfs_fs_type = {
- .owner = THIS_MODULE,
- .name = "nfs",
- .mount = nfs_fs_mount,
- .kill_sb = nfs_kill_super,
- .fs_flags = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
-};
-MODULE_ALIAS_FS("nfs");
-EXPORT_SYMBOL_GPL(nfs_fs_type);
-
-struct file_system_type nfs_prepared_fs_type = {
- .owner = THIS_MODULE,
- .name = "nfs",
- .mount = nfs_prepared_mount,
- .kill_sb = nfs_kill_super,
- .fs_flags = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
-};
-EXPORT_SYMBOL_GPL(nfs_prepared_fs_type);
-
const struct super_operations nfs_sops = {
.alloc_inode = nfs_alloc_inode,
.free_inode = nfs_free_inode,
@@ -104,22 +82,10 @@ const struct super_operations nfs_sops = {
.show_devname = nfs_show_devname,
.show_path = nfs_show_path,
.show_stats = nfs_show_stats,
- .remount_fs = nfs_remount,
};
EXPORT_SYMBOL_GPL(nfs_sops);

#if IS_ENABLED(CONFIG_NFS_V4)
-struct file_system_type nfs4_fs_type = {
- .owner = THIS_MODULE,
- .name = "nfs4",
- .mount = nfs_fs_mount,
- .kill_sb = nfs_kill_super,
- .fs_flags = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
-};
-MODULE_ALIAS_FS("nfs4");
-MODULE_ALIAS("nfs4");
-EXPORT_SYMBOL_GPL(nfs4_fs_type);
-
static int __init register_nfs4_fs(void)
{
return register_filesystem(&nfs4_fs_type);
@@ -911,20 +877,19 @@ static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_inf
return nfs_mod->rpc_ops->create_server(mount_info);
}

-static struct dentry *nfs_fs_mount_common(int, const char *, struct nfs_mount_info *);
-
-struct dentry *nfs_try_mount(int flags, const char *dev_name,
- struct nfs_mount_info *mount_info)
+int nfs_try_get_tree(struct fs_context *fc)
{
- struct nfs_subversion *nfs_mod = mount_info->nfs_mod;
- if (mount_info->ctx->need_mount)
- mount_info->server = nfs_try_mount_request(mount_info);
+ struct nfs_fs_context *ctx = nfs_fc2context(fc);
+
+ if (ctx->need_mount)
+ ctx->mount_info.server = nfs_try_mount_request(&ctx->mount_info);
else
- mount_info->server = nfs_mod->rpc_ops->create_server(mount_info);
+ ctx->mount_info.server = ctx->mount_info.nfs_mod->rpc_ops->create_server(&ctx->mount_info);

- return nfs_fs_mount_common(flags, dev_name, mount_info);
+ return nfs_get_tree_common(fc);
}
-EXPORT_SYMBOL_GPL(nfs_try_mount);
+EXPORT_SYMBOL_GPL(nfs_try_get_tree);
+

#define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
| NFS_MOUNT_SECURE \
@@ -965,15 +930,11 @@ nfs_compare_remount_data(struct nfs_server *nfss,
return 0;
}

-int
-nfs_remount(struct super_block *sb, int *flags, char *raw_data)
+int nfs_reconfigure(struct fs_context *fc)
{
- int error;
+ struct nfs_fs_context *ctx = nfs_fc2context(fc);
+ struct super_block *sb = fc->root->d_sb;
struct nfs_server *nfss = sb->s_fs_info;
- struct nfs_fs_context *ctx;
- struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
- struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
- u32 nfsvers = nfss->nfs_client->rpc_ops->version;

sync_filesystem(sb);

@@ -983,57 +944,24 @@ nfs_remount(struct super_block *sb, int *flags, char *raw_data)
* ones were explicitly specified. Fall back to legacy behavior and
* just return success.
*/
- if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
- (nfsvers <= 3 && (!options || (options->version >= 1 &&
- options->version <= 6))))
+ if (ctx->skip_reconfig_option_check)
return 0;

- ctx = nfs_alloc_parsed_mount_data();
- if (ctx == NULL)
- return -ENOMEM;
-
- /* fill out struct with values from existing mount */
- ctx->flags = nfss->flags;
- ctx->rsize = nfss->rsize;
- ctx->wsize = nfss->wsize;
- ctx->retrans = nfss->client->cl_timeout->to_retries;
- ctx->selected_flavor = nfss->client->cl_auth->au_flavor;
- ctx->acregmin = nfss->acregmin / HZ;
- ctx->acregmax = nfss->acregmax / HZ;
- ctx->acdirmin = nfss->acdirmin / HZ;
- ctx->acdirmax = nfss->acdirmax / HZ;
- ctx->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
- ctx->nfs_server.port = nfss->port;
- ctx->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
- ctx->version = nfsvers;
- ctx->minorversion = nfss->nfs_client->cl_minorversion;
- ctx->net = current->nsproxy->net_ns;
- memcpy(&ctx->nfs_server.address, &nfss->nfs_client->cl_addr,
- ctx->nfs_server.addrlen);
-
- /* overwrite those values with any that were specified */
- error = -EINVAL;
- if (!nfs_parse_mount_options((char *)options, ctx))
- goto out;
-
/*
* noac is a special case. It implies -o sync, but that's not
- * necessarily reflected in the mtab options. do_remount_sb
+ * necessarily reflected in the mtab options. reconfigure_super
* will clear SB_SYNCHRONOUS if -o sync wasn't specified in the
* remount options, so we have to explicitly reset it.
*/
- if (ctx->flags & NFS_MOUNT_NOAC)
- *flags |= SB_SYNCHRONOUS;
+ if (ctx->flags & NFS_MOUNT_NOAC) {
+ fc->sb_flags |= SB_SYNCHRONOUS;
+ fc->sb_flags_mask |= SB_SYNCHRONOUS;
+ }

/* compare new mount options with old ones */
- error = nfs_compare_remount_data(nfss, ctx);
- if (!error)
- error = security_sb_remount(sb, ctx->lsm_opts);
-out:
- nfs_free_parsed_mount_data(ctx);
- return error;
+ return nfs_compare_remount_data(nfss, ctx);
}
-EXPORT_SYMBOL_GPL(nfs_remount);
+EXPORT_SYMBOL_GPL(nfs_reconfigure);

/*
* Finish setting up an NFS superblock
@@ -1112,19 +1040,11 @@ static int nfs_compare_mount_options(const struct super_block *s, const struct n
return 0;
}

-struct nfs_sb_mountdata {
- struct nfs_server *server;
- int mntflags;
-};
-
-static int nfs_set_super(struct super_block *s, void *data)
+static int nfs_set_super(struct super_block *s, struct fs_context *fc)
{
- struct nfs_sb_mountdata *sb_mntdata = data;
- struct nfs_server *server = sb_mntdata->server;
+ struct nfs_server *server = fc->s_fs_info;
int ret;

- s->s_flags = sb_mntdata->mntflags;
- s->s_fs_info = server;
s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
ret = set_anon_super(s, server);
if (ret == 0)
@@ -1189,11 +1109,9 @@ static int nfs_compare_userns(const struct nfs_server *old,
return 1;
}

-static int nfs_compare_super(struct super_block *sb, void *data)
+static int nfs_compare_super(struct super_block *sb, struct fs_context *fc)
{
- struct nfs_sb_mountdata *sb_mntdata = data;
- struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
- int mntflags = sb_mntdata->mntflags;
+ struct nfs_server *server = fc->s_fs_info, *old = NFS_SB(sb);

if (!nfs_compare_super_address(old, server))
return 0;
@@ -1204,13 +1122,12 @@ static int nfs_compare_super(struct super_block *sb, void *data)
return 0;
if (!nfs_compare_userns(old, server))
return 0;
- return nfs_compare_mount_options(sb, server, mntflags);
+ return nfs_compare_mount_options(sb, server, fc->sb_flags);
}

#ifdef CONFIG_NFS_FSCACHE
static void nfs_get_cache_cookie(struct super_block *sb,
- struct nfs_fs_context *ctx,
- struct nfs_clone_mount *cloned)
+ struct nfs_fs_context *ctx)
{
struct nfs_server *nfss = NFS_SB(sb);
char *uniq = NULL;
@@ -1219,30 +1136,32 @@ static void nfs_get_cache_cookie(struct super_block *sb,
nfss->fscache_key = NULL;
nfss->fscache = NULL;

- if (ctx) {
- if (!(ctx->options & NFS_OPTION_FSCACHE))
- return;
- if (ctx->fscache_uniq) {
- uniq = ctx->fscache_uniq;
- ulen = strlen(ctx->fscache_uniq);
- }
- } else if (cloned) {
- struct nfs_server *mnt_s = NFS_SB(cloned->sb);
+ if (!ctx)
+ return;
+
+ if (ctx->clone_data.sb) {
+ struct nfs_server *mnt_s = NFS_SB(ctx->clone_data.sb);
if (!(mnt_s->options & NFS_OPTION_FSCACHE))
return;
if (mnt_s->fscache_key) {
uniq = mnt_s->fscache_key->key.uniquifier;
ulen = mnt_s->fscache_key->key.uniq_len;
}
- } else
+ } else {
+ if (!(ctx->options & NFS_OPTION_FSCACHE))
+ return;
+ if (ctx->fscache_uniq) {
+ uniq = ctx->fscache_uniq;
+ ulen = strlen(ctx->fscache_uniq);
+ }
return;
+ }

nfs_fscache_get_super_cookie(sb, uniq, ulen);
}
#else
static void nfs_get_cache_cookie(struct super_block *sb,
- struct nfs_fs_context *parsed,
- struct nfs_clone_mount *cloned)
+ struct nfs_fs_context *ctx)
{
}
#endif
@@ -1254,40 +1173,41 @@ static void nfs_set_readahead(struct backing_dev_info *bdi,
bdi->io_pages = iomax_pages;
}

-static struct dentry *nfs_fs_mount_common(int flags, const char *dev_name,
- struct nfs_mount_info *mount_info)
+int nfs_get_tree_common(struct fs_context *fc)
{
+ struct nfs_fs_context *ctx = nfs_fc2context(fc);
struct super_block *s;
struct dentry *mntroot = ERR_PTR(-ENOMEM);
- int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
- struct nfs_server *server = mount_info->server;
+ int (*compare_super)(struct super_block *, struct fs_context *) = nfs_compare_super;
+ struct nfs_server *server = ctx->mount_info.server;
unsigned long kflags = 0, kflags_out = 0;
- struct nfs_sb_mountdata sb_mntdata = {
- .mntflags = flags,
- .server = server,
- };
int error;

- mount_info->server = NULL;
+ ctx->mount_info.server = NULL;
if (IS_ERR(server))
- return ERR_CAST(server);
+ return PTR_ERR(server);

if (server->flags & NFS_MOUNT_UNSHARED)
compare_super = NULL;

/* -o noac implies -o sync */
if (server->flags & NFS_MOUNT_NOAC)
- sb_mntdata.mntflags |= SB_SYNCHRONOUS;
+ fc->sb_flags |= SB_SYNCHRONOUS;
+
+ if (ctx->clone_data.sb)
+ if (ctx->clone_data.sb->s_flags & SB_SYNCHRONOUS)
+ fc->sb_flags |= SB_SYNCHRONOUS;

- if (mount_info->cloned != NULL && mount_info->cloned->sb != NULL)
- if (mount_info->cloned->sb->s_flags & SB_SYNCHRONOUS)
- sb_mntdata.mntflags |= SB_SYNCHRONOUS;
+ if (server->caps & NFS_CAP_SECURITY_LABEL)
+ fc->lsm_flags |= SECURITY_LSM_NATIVE_LABELS;

/* Get a superblock - note that we may end up sharing one that already exists */
- s = sget(mount_info->nfs_mod->nfs_fs, compare_super, nfs_set_super,
- flags, &sb_mntdata);
+ fc->s_fs_info = server;
+ s = sget_fc(fc, compare_super, nfs_set_super);
+ fc->s_fs_info = NULL;
if (IS_ERR(s)) {
- mntroot = ERR_CAST(s);
+ error = PTR_ERR(s);
+ dfprintk(MOUNT, "NFS: Couldn't get superblock\n");
goto out_err_nosb;
}

@@ -1297,44 +1217,43 @@ static struct dentry *nfs_fs_mount_common(int flags, const char *dev_name,
} else {
error = super_setup_bdi_name(s, "%u:%u", MAJOR(server->s_dev),
MINOR(server->s_dev));
- if (error) {
- mntroot = ERR_PTR(error);
+ if (error)
goto error_splat_super;
- }
nfs_set_readahead(s->s_bdi, server->rpages);
server->super = s;
}

if (!s->s_root) {
- unsigned bsize = mount_info->inherited_bsize;
+ unsigned bsize = ctx->mount_info.inherited_bsize;
/* initial superblock/root creation */
- nfs_fill_super(s, mount_info);
+ nfs_fill_super(s, &ctx->mount_info);
if (bsize) {
s->s_blocksize_bits = bsize;
s->s_blocksize = 1U << bsize;
}
- nfs_get_cache_cookie(s, mount_info->ctx, mount_info->cloned);
- if (!(server->flags & NFS_MOUNT_UNSHARED))
- s->s_iflags |= SB_I_MULTIROOT;
+ nfs_get_cache_cookie(s, ctx);
}

- mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
- if (IS_ERR(mntroot))
+ mntroot = nfs_get_root(s, ctx->mount_info.mntfh, fc->source);
+ if (IS_ERR(mntroot)) {
+ error = PTR_ERR(mntroot);
+ dfprintk(MOUNT, "NFS: Couldn't get root dentry\n");
goto error_splat_super;
-
+ }
+ fc->root = mntroot;

if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
kflags |= SECURITY_LSM_NATIVE_LABELS;
- if (mount_info->cloned) {
- if (d_inode(mntroot)->i_fop != &nfs_dir_operations) {
+ if (ctx->clone_data.sb) {
+ if (d_inode(fc->root)->i_fop != &nfs_dir_operations) {
error = -ESTALE;
goto error_splat_root;
}
/* clone any lsm security options from the parent to the new sb */
- error = security_sb_clone_mnt_opts(mount_info->cloned->sb, s, kflags,
+ error = security_sb_clone_mnt_opts(ctx->clone_data.sb, s, kflags,
&kflags_out);
} else {
- error = security_sb_set_mnt_opts(s, mount_info->ctx->lsm_opts,
+ error = security_sb_set_mnt_opts(s, fc->security,
kflags, &kflags_out);
}
if (error)
@@ -1342,67 +1261,25 @@ static struct dentry *nfs_fs_mount_common(int flags, const char *dev_name,
if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
!(kflags_out & SECURITY_LSM_NATIVE_LABELS))
NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
- if (error)
- goto error_splat_root;

s->s_flags |= SB_ACTIVE;
+ error = 0;

out:
- return mntroot;
+ return error;

out_err_nosb:
nfs_free_server(server);
goto out;

error_splat_root:
- dput(mntroot);
- mntroot = ERR_PTR(error);
+ dput(fc->root);
+ fc->root = NULL;
error_splat_super:
deactivate_locked_super(s);
goto out;
}

-struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
- int flags, const char *dev_name, void *raw_data)
-{
- struct nfs_mount_info mount_info = {
- };
- struct dentry *mntroot = ERR_PTR(-ENOMEM);
- struct nfs_subversion *nfs_mod;
- int error;
-
- mount_info.ctx = nfs_alloc_parsed_mount_data();
- mount_info.mntfh = nfs_alloc_fhandle();
- if (mount_info.ctx == NULL || mount_info.mntfh == NULL)
- goto out;
-
- /* Validate the mount data */
- error = nfs_validate_mount_data(fs_type, raw_data, mount_info.ctx, mount_info.mntfh, dev_name);
- if (error == NFS_TEXT_DATA)
- error = nfs_validate_text_mount_data(raw_data,
- mount_info.ctx, dev_name);
- if (error < 0) {
- mntroot = ERR_PTR(error);
- goto out;
- }
-
- nfs_mod = get_nfs_version(mount_info.ctx->version);
- if (IS_ERR(nfs_mod)) {
- mntroot = ERR_CAST(nfs_mod);
- goto out;
- }
- mount_info.nfs_mod = nfs_mod;
-
- mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info);
-
- put_nfs_version(nfs_mod);
-out:
- nfs_free_parsed_mount_data(mount_info.ctx);
- nfs_free_fhandle(mount_info.mntfh);
- return mntroot;
-}
-EXPORT_SYMBOL_GPL(nfs_fs_mount);
-
/*
* Destroy an NFS2/3 superblock
*/
@@ -1420,17 +1297,6 @@ void nfs_kill_super(struct super_block *s)
}
EXPORT_SYMBOL_GPL(nfs_kill_super);

-/*
- * Internal use only: mount_info is already set up by caller.
- * Used for mountpoint crossings and for nfs4 root.
- */
-static struct dentry *
-nfs_prepared_mount(struct file_system_type *fs_type, int flags,
- const char *dev_name, void *raw_data)
-{
- return nfs_fs_mount_common(flags, dev_name, raw_data);
-}
-
#if IS_ENABLED(CONFIG_NFS_V4)

/*
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 17527f6e6360..574741d5418d 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -1639,6 +1639,7 @@ struct nfs_subversion;
struct nfs_mount_info;
struct nfs_client_initdata;
struct nfs_pageio_descriptor;
+struct fs_context;

/*
* RPC procedure vector for NFSv2/NFSv3 demuxing
@@ -1653,9 +1654,8 @@ struct nfs_rpc_ops {

int (*getroot) (struct nfs_server *, struct nfs_fh *,
struct nfs_fsinfo *);
- struct vfsmount *(*submount) (struct nfs_server *, struct dentry *,
- struct nfs_fh *, struct nfs_fattr *);
- struct dentry *(*try_mount) (int, const char *, struct nfs_mount_info *);
+ int (*submount) (struct fs_context *, struct nfs_server *);
+ int (*try_get_tree) (struct fs_context *);
int (*getattr) (struct nfs_server *, struct nfs_fh *,
struct nfs_fattr *, struct nfs4_label *,
struct inode *);
--
2.17.2