1 files changed, 58 insertions, 34 deletions

diff --git a/kernel/bpf/inode.c b/kernel/bpf/inode.c
index cc0d0cf114e3..a70f7209cda3 100644
--- a/kernel/bpf/inode.c
+++ b/kernel/bpf/inode.c
@@ -14,8 +14,9 @@
 #include <linux/mount.h>
 #include <linux/namei.h>
 #include <linux/fs.h>
+#include <linux/fs_context.h>
+#include <linux/fs_parser.h>
 #include <linux/kdev_t.h>
-#include <linux/parser.h>
 #include <linux/filter.h>
 #include <linux/bpf.h>
 #include <linux/bpf_trace.h>
@@ -583,58 +584,52 @@ static const struct super_operations bpf_super_ops = {
 
 enum {
         OPT_MODE,
-        OPT_ERR,
 };
 
-static const match_table_t bpf_mount_tokens = {
-        { OPT_MODE, "mode=%o" },
-        { OPT_ERR, NULL },
+static const struct fs_parameter_spec bpf_param_specs[] = {
+        fsparam_u32oct  ("mode",                        OPT_MODE),
+        {}
+};
+
+static const struct fs_parameter_description bpf_fs_parameters = {
+        .name           = "bpf",
+        .specs          = bpf_param_specs,
 };
 
 struct bpf_mount_opts {
         umode_t mode;
 };
 
-static int bpf_parse_options(char *data, struct bpf_mount_opts *opts)
+static int bpf_parse_param(struct fs_context *fc, struct fs_parameter *param)
 {
-        substring_t args[MAX_OPT_ARGS];
-        int option, token;
-        char *ptr;
+        struct bpf_mount_opts *opts = fc->fs_private;
+        struct fs_parse_result result;
+        int opt;
 
-        opts->mode = S_IRWXUGO;
-
-        while ((ptr = strsep(&data, ",")) != NULL) {
-                if (!*ptr)
-                        continue;
-
-                token = match_token(ptr, bpf_mount_tokens, args);
-                switch (token) {
-                case OPT_MODE:
-                        if (match_octal(&args[0], &option))
-                                return -EINVAL;
-                        opts->mode = option & S_IALLUGO;
-                        break;
+        opt = fs_parse(fc, &bpf_fs_parameters, param, &result);
+        if (opt < 0)
                 /* We might like to report bad mount options here, but
                  * traditionally we've ignored all mount options, so we'd
                  * better continue to ignore non-existing options for bpf.
                  */
-                }
+                return opt == -ENOPARAM ? 0 : opt;
+
+        switch (opt) {
+        case OPT_MODE:
+                opts->mode = result.uint_32 & S_IALLUGO;
+                break;
         }
 
         return 0;
 }
 
-static int bpf_fill_super(struct super_block *sb, void *data, int silent)
+static int bpf_fill_super(struct super_block *sb, struct fs_context *fc)
 {
         static const struct tree_descr bpf_rfiles[] = { { "" } };
-        struct bpf_mount_opts opts;
+        struct bpf_mount_opts *opts = fc->fs_private;
         struct inode *inode;
         int ret;
 
-        ret = bpf_parse_options(data, &opts);
-        if (ret)
-                return ret;
-
         ret = simple_fill_super(sb, BPF_FS_MAGIC, bpf_rfiles);
         if (ret)
                 return ret;
@@ -644,21 +639,50 @@ static int bpf_fill_super(struct super_block *sb, void *data, int silent)
         inode = sb->s_root->d_inode;
         inode->i_op = &bpf_dir_iops;
         inode->i_mode &= ~S_IALLUGO;
-        inode->i_mode |= S_ISVTX | opts.mode;
+        inode->i_mode |= S_ISVTX | opts->mode;
 
         return 0;
 }
 
-static struct dentry *bpf_mount(struct file_system_type *type, int flags,
-                                const char *dev_name, void *data)
+static int bpf_get_tree(struct fs_context *fc)
+{
+        return get_tree_nodev(fc, bpf_fill_super);
+}
+
+static void bpf_free_fc(struct fs_context *fc)
 {
-        return mount_nodev(type, flags, data, bpf_fill_super);
+        kfree(fc->fs_private);
+}
+
+static const struct fs_context_operations bpf_context_ops = {
+        .free           = bpf_free_fc,
+        .parse_param    = bpf_parse_param,
+        .get_tree       = bpf_get_tree,
+};
+
+/*
+ * Set up the filesystem mount context.
+ */
+static int bpf_init_fs_context(struct fs_context *fc)
+{
+        struct bpf_mount_opts *opts;
+
+        opts = kzalloc(sizeof(struct bpf_mount_opts), GFP_KERNEL);
+        if (!opts)
+                return -ENOMEM;
+
+        opts->mode = S_IRWXUGO;
+
+        fc->fs_private = opts;
+        fc->ops = &bpf_context_ops;
+        return 0;
 }
 
 static struct file_system_type bpf_fs_type = {
         .owner          = THIS_MODULE,
         .name           = "bpf",
-        .mount          = bpf_mount,
+        .init_fs_context = bpf_init_fs_context,
+        .parameters     = &bpf_fs_parameters,
         .kill_sb        = kill_litter_super,
 };