From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
[dhowells should be the author - it's carved out of his patch]
Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
kernel/cgroup/cgroup-internal.h | 3 -
kernel/cgroup/cgroup-v1.c | 192 ++++++++++++++++++++++-----------------
kernel/cgroup/cgroup.c | 20 +---
3 files changed, 117 insertions(+), 98 deletions(-)
diff --git a/kernel/cgroup/cgroup-internal.h b/kernel/cgroup/cgroup-internal.h
index e627ff193dba..a7b5a41f170c 100644
--- a/kernel/cgroup/cgroup-internal.h
+++ b/kernel/cgroup/cgroup-internal.h
@@ -257,14 +257,15 @@ extern const struct proc_ns_operations cgroupns_operations;
*/
extern struct cftype cgroup1_base_files[];
extern struct kernfs_syscall_ops cgroup1_kf_syscall_ops;
+extern const struct fs_parameter_description cgroup1_fs_parameters;
int proc_cgroupstats_show(struct seq_file *m, void *v);
bool cgroup1_ssid_disabled(int ssid);
void cgroup1_pidlist_destroy_all(struct cgroup *cgrp);
void cgroup1_release_agent(struct work_struct *work);
void cgroup1_check_for_release(struct cgroup *cgrp);
+int cgroup1_parse_param(struct fs_context *fc, struct fs_parameter *param);
int cgroup1_get_tree(struct fs_context *fc);
-int parse_cgroup1_options(char *data, struct cgroup_fs_context *ctx);
int cgroup1_reconfigure(struct fs_context *ctx);
#endif /* __CGROUP_INTERNAL_H */
diff --git a/kernel/cgroup/cgroup-v1.c b/kernel/cgroup/cgroup-v1.c
index 5c93643090e9..725e9f6fe80d 100644
--- a/kernel/cgroup/cgroup-v1.c
+++ b/kernel/cgroup/cgroup-v1.c
@@ -13,9 +13,12 @@
#include <linux/delayacct.h>
#include <linux/pid_namespace.h>
#include <linux/cgroupstats.h>
+#include <linux/fs_parser.h>
#include <trace/events/cgroup.h>
+#define cg_invalf(fc, fmt, ...) ({ pr_err(fmt, ## __VA_ARGS__); -EINVAL; })
+
/*
* pidlists linger the following amount before being destroyed. The goal
* is avoiding frequent destruction in the middle of consecutive read calls
@@ -906,94 +909,117 @@ static int cgroup1_show_options(struct seq_file *seq, struct kernfs_root *kf_roo
return 0;
}
-int parse_cgroup1_options(char *data, struct cgroup_fs_context *ctx)
-{
- char *token, *o = data;
- struct cgroup_subsys *ss;
- int i;
+enum cgroup1_param {
+ Opt_all,
+ Opt_clone_children,
+ Opt_cpuset_v2_mode,
+ Opt_name,
+ Opt_none,
+ Opt_noprefix,
+ Opt_release_agent,
+ Opt_xattr,
+};
- while ((token = strsep(&o, ",")) != NULL) {
- if (!*token)
- return -EINVAL;
- if (!strcmp(token, "none")) {
- /* Explicitly have no subsystems */
- ctx->none = true;
- continue;
- }
- if (!strcmp(token, "all")) {
- ctx->all_ss = true;
- continue;
- }
- if (!strcmp(token, "noprefix")) {
- ctx->flags |= CGRP_ROOT_NOPREFIX;
- continue;
- }
- if (!strcmp(token, "clone_children")) {
- ctx->cpuset_clone_children = true;
- continue;
- }
- if (!strcmp(token, "cpuset_v2_mode")) {
- ctx->flags |= CGRP_ROOT_CPUSET_V2_MODE;
- continue;
- }
- if (!strcmp(token, "xattr")) {
- ctx->flags |= CGRP_ROOT_XATTR;
- continue;
- }
- if (!strncmp(token, "release_agent=", 14)) {
- /* Specifying two release agents is forbidden */
- if (ctx->release_agent)
- return -EINVAL;
- ctx->release_agent =
- kstrndup(token + 14, PATH_MAX - 1, GFP_KERNEL);
- if (!ctx->release_agent)
- return -ENOMEM;
- continue;
- }
- if (!strncmp(token, "name=", 5)) {
- const char *name = token + 5;
-
- /* blocked by boot param? */
- if (cgroup_no_v1_named)
- return -ENOENT;
- /* Can't specify an empty name */
- if (!strlen(name))
- return -EINVAL;
- /* Must match [\w.-]+ */
- for (i = 0; i < strlen(name); i++) {
- char c = name[i];
- if (isalnum(c))
- continue;
- if ((c == '.') || (c == '-') || (c == '_'))
- continue;
- return -EINVAL;
- }
- /* Specifying two names is forbidden */
- if (ctx->name)
- return -EINVAL;
- ctx->name = kstrndup(name,
- MAX_CGROUP_ROOT_NAMELEN - 1,
- GFP_KERNEL);
- if (!ctx->name)
- return -ENOMEM;
+static const struct fs_parameter_spec cgroup1_param_specs[] = {
+ fsparam_flag ("all", Opt_all),
+ fsparam_flag ("clone_children", Opt_clone_children),
+ fsparam_flag ("cpuset_v2_mode", Opt_cpuset_v2_mode),
+ fsparam_string("name", Opt_name),
+ fsparam_flag ("none", Opt_none),
+ fsparam_flag ("noprefix", Opt_noprefix),
+ fsparam_string("release_agent", Opt_release_agent),
+ fsparam_flag ("xattr", Opt_xattr),
+ {}
+};
- continue;
- }
+const struct fs_parameter_description cgroup1_fs_parameters = {
+ .name = "cgroup1",
+ .specs = cgroup1_param_specs,
+};
+int cgroup1_parse_param(struct fs_context *fc, struct fs_parameter *param)
+{
+ struct cgroup_fs_context *ctx = cgroup_fc2context(fc);
+ struct cgroup_subsys *ss;
+ struct fs_parse_result result;
+ int opt, i;
+
+ opt = fs_parse(fc, &cgroup1_fs_parameters, param, &result);
+ if (opt == -ENOPARAM) {
+ if (strcmp(param->key, "source") == 0) {
+ fc->source = param->string;
+ param->string = NULL;
+ return 0;
+ }
for_each_subsys(ss, i) {
- if (strcmp(token, ss->legacy_name))
+ if (strcmp(param->key, ss->legacy_name))
continue;
ctx->subsys_mask |= (1 << i);
- break;
+ return 0;
}
- if (i == CGROUP_SUBSYS_COUNT)
+ return cg_invalf(fc, "cgroup1: Unknown subsys name '%s'", param->key);
+ }
+ if (opt < 0)
+ return opt;
+
+ switch (opt) {
+ case Opt_none:
+ /* Explicitly have no subsystems */
+ ctx->none = true;
+ break;
+ case Opt_all:
+ ctx->all_ss = true;
+ break;
+ case Opt_noprefix:
+ ctx->flags |= CGRP_ROOT_NOPREFIX;
+ break;
+ case Opt_clone_children:
+ ctx->cpuset_clone_children = true;
+ break;
+ case Opt_cpuset_v2_mode:
+ ctx->flags |= CGRP_ROOT_CPUSET_V2_MODE;
+ break;
+ case Opt_xattr:
+ ctx->flags |= CGRP_ROOT_XATTR;
+ break;
+ case Opt_release_agent:
+ /* Specifying two release agents is forbidden */
+ if (ctx->release_agent)
+ return cg_invalf(fc, "cgroup1: release_agent respecified");
+ ctx->release_agent = param->string;
+ param->string = NULL;
+ break;
+ case Opt_name:
+ /* blocked by boot param? */
+ if (cgroup_no_v1_named)
return -ENOENT;
+ /* Can't specify an empty name */
+ if (!param->size)
+ return cg_invalf(fc, "cgroup1: Empty name");
+ if (param->size > MAX_CGROUP_ROOT_NAMELEN - 1)
+ return cg_invalf(fc, "cgroup1: Name too long");
+ /* Must match [\w.-]+ */
+ for (i = 0; i < param->size; i++) {
+ char c = param->string[i];
+ if (isalnum(c))
+ continue;
+ if ((c == '.') || (c == '-') || (c == '_'))
+ continue;
+ return cg_invalf(fc, "cgroup1: Invalid name");
+ }
+ /* Specifying two names is forbidden */
+ if (ctx->name)
+ return cg_invalf(fc, "cgroup1: name respecified");
+ ctx->name = param->string;
+ param->string = NULL;
+ break;
}
return 0;
}
-static int check_cgroupfs_options(struct cgroup_fs_context *ctx)
+static int check_cgroupfs_options(struct fs_context *fc)
{
+ struct cgroup_fs_context *ctx = cgroup_fc2context(fc);
u16 mask = U16_MAX;
u16 enabled = 0;
struct cgroup_subsys *ss;
@@ -1018,7 +1044,7 @@ static int check_cgroupfs_options(struct cgroup_fs_context *ctx)
if (ctx->all_ss) {
/* Mutually exclusive option 'all' + subsystem name */
if (ctx->subsys_mask)
- return -EINVAL;
+ return cg_invalf(fc, "cgroup1: subsys name conflicts with all");
/* 'all' => select all the subsystems */
ctx->subsys_mask = enabled;
}
@@ -1028,7 +1054,7 @@ static int check_cgroupfs_options(struct cgroup_fs_context *ctx)
* empty hierarchies must have a name).
*/
if (!ctx->subsys_mask && !ctx->name)
- return -EINVAL;
+ return cg_invalf(fc, "cgroup1: Need name or subsystem set");
/*
* Option noprefix was introduced just for backward compatibility
@@ -1036,11 +1062,11 @@ static int check_cgroupfs_options(struct cgroup_fs_context *ctx)
* the cpuset subsystem.
*/
if ((ctx->flags & CGRP_ROOT_NOPREFIX) && (ctx->subsys_mask & mask))
- return -EINVAL;
+ return cg_invalf(fc, "cgroup1: noprefix used incorrectly");
/* Can't specify "none" and some subsystems */
if (ctx->subsys_mask && ctx->none)
- return -EINVAL;
+ return cg_invalf(fc, "cgroup1: none used incorrectly");
return 0;
}
@@ -1056,7 +1082,7 @@ int cgroup1_reconfigure(struct fs_context *fc)
cgroup_lock_and_drain_offline(&cgrp_dfl_root.cgrp);
/* See what subsystems are wanted */
- ret = check_cgroupfs_options(ctx);
+ ret = check_cgroupfs_options(fc);
if (ret)
goto out_unlock;
@@ -1070,7 +1096,7 @@ int cgroup1_reconfigure(struct fs_context *fc)
/* Don't allow flags or name to change at remount */
if ((ctx->flags ^ root->flags) ||
(ctx->name && strcmp(ctx->name, root->name))) {
- pr_err("option or name mismatch, new: 0x%x \"%s\", old: 0x%x \"%s\"\n",
+ cg_invalf(fc, "option or name mismatch, new: 0x%x \"%s\", old: 0x%x \"%s\"",
ctx->flags, ctx->name ?: "", root->flags, root->name);
ret = -EINVAL;
goto out_unlock;
@@ -1125,7 +1151,7 @@ int cgroup1_get_tree(struct fs_context *fc)
cgroup_lock_and_drain_offline(&cgrp_dfl_root.cgrp);
/* First find the desired set of subsystems */
- ret = check_cgroupfs_options(ctx);
+ ret = check_cgroupfs_options(fc);
if (ret)
goto out_unlock;
@@ -1192,7 +1218,7 @@ int cgroup1_get_tree(struct fs_context *fc)
* can't create new one without subsys specification.
*/
if (!ctx->subsys_mask && !ctx->none) {
- ret = -EINVAL;
+ ret = cg_invalf(fc, "cgroup1: No subsys list or none specified");
goto out_unlock;
}
diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index 33da9eef3ef4..faba00caa197 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -2083,15 +2083,6 @@ static int cgroup_parse_monolithic(struct fs_context *fc, void *data)
return parse_cgroup_root_flags(data, &ctx->flags);
}
-static int cgroup1_parse_monolithic(struct fs_context *fc, void *data)
-{
- struct cgroup_fs_context *ctx = cgroup_fc2context(fc);
-
- if (data)
- security_sb_eat_lsm_opts(data, &fc->security);
- return parse_cgroup1_options(data, ctx);
-}
-
static int cgroup_get_tree(struct fs_context *fc)
{
struct cgroup_namespace *ns = current->nsproxy->cgroup_ns;
@@ -2124,7 +2115,7 @@ static const struct fs_context_operations cgroup_fs_context_ops = {
static const struct fs_context_operations cgroup1_fs_context_ops = {
.free = cgroup_fs_context_free,
- .parse_monolithic = cgroup1_parse_monolithic,
+ .parse_param = cgroup1_parse_param,
.get_tree = cgroup1_get_tree,
.reconfigure = cgroup1_reconfigure,
};
@@ -2175,10 +2166,11 @@ static void cgroup_kill_sb(struct super_block *sb)
}
struct file_system_type cgroup_fs_type = {
- .name = "cgroup",
- .init_fs_context = cgroup_init_fs_context,
- .kill_sb = cgroup_kill_sb,
- .fs_flags = FS_USERNS_MOUNT,
+ .name = "cgroup",
+ .init_fs_context = cgroup_init_fs_context,
+ .parameters = &cgroup1_fs_parameters,
+ .kill_sb = cgroup_kill_sb,
+ .fs_flags = FS_USERNS_MOUNT,
};
static struct file_system_type cgroup2_fs_type = {
