Convert the pstore filesystem to the new mount API.
Cc: Kees Cook <kees@xxxxxxxxxx>
Cc: Tony Luck <tony.luck@xxxxxxxxx>
Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxx>
---
fs/pstore/inode.c | 111 +++++++++++++++++++++++++++++++---------------
1 file changed, 75 insertions(+), 36 deletions(-)
diff --git a/fs/pstore/inode.c b/fs/pstore/inode.c
index 56815799ce79..3a4582b79c75 100644
--- a/fs/pstore/inode.c
+++ b/fs/pstore/inode.c
@@ -14,10 +14,10 @@
#include <linux/init.h>
#include <linux/list.h>
#include <linux/string.h>
-#include <linux/mount.h>
#include <linux/seq_file.h>
#include <linux/ramfs.h>
-#include <linux/parser.h>
+#include <linux/fs_parser.h>
+#include <linux/fs_context.h>
#include <linux/sched.h>
#include <linux/magic.h>
#include <linux/pstore.h>
@@ -226,37 +226,38 @@ static struct inode *pstore_get_inode(struct super_block *sb)
}
enum {
- Opt_kmsg_bytes, Opt_err
+ Opt_kmsg_bytes
};
-static const match_table_t tokens = {
- {Opt_kmsg_bytes, "kmsg_bytes=%u"},
- {Opt_err, NULL}
+static const struct fs_parameter_spec pstore_param_spec[] = {
+ fsparam_u32 ("kmsg_bytes", Opt_kmsg_bytes),
+ {}
};
-static void parse_options(char *options)
-{
- char *p;
- substring_t args[MAX_OPT_ARGS];
- int option;
-
- if (!options)
- return;
+struct pstore_context {
+ unsigned int kmsg_bytes;
+};
- while ((p = strsep(&options, ",")) != NULL) {
- int token;
+static int pstore_parse_param(struct fs_context *fc, struct fs_parameter *param)
+{
+ struct pstore_context *ctx = fc->fs_private;
+ struct fs_parse_result result;
+ int opt;
- if (!*p)
- continue;
+ opt = fs_parse(fc, pstore_param_spec, param, &result);
+ /* pstore has historically ignored invalid kmsg_bytes param */
+ if (opt < 0)
+ return 0;
- token = match_token(p, tokens, args);
- switch (token) {
- case Opt_kmsg_bytes:
- if (!match_int(&args[0], &option))
- pstore_set_kmsg_bytes(option);
- break;
- }
+ switch (opt) {
+ case Opt_kmsg_bytes:
+ ctx->kmsg_bytes = result.uint_32;
+ break;
+ default:
+ return -EINVAL;
}
+
+ return 0;
}
/*
@@ -269,10 +270,12 @@ static int pstore_show_options(struct seq_file *m, struct dentry *root)
return 0;
}
-static int pstore_remount(struct super_block *sb, int *flags, char *data)
+static int pstore_reconfigure(struct fs_context *fc)
{
- sync_filesystem(sb);
- parse_options(data);
+ struct pstore_context *ctx = fc->fs_private;
+
+ sync_filesystem(fc->root->d_sb);
+ pstore_set_kmsg_bytes(ctx->kmsg_bytes);
return 0;
}
@@ -281,7 +284,6 @@ static const struct super_operations pstore_ops = {
.statfs = simple_statfs,
.drop_inode = generic_delete_inode,
.evict_inode = pstore_evict_inode,
- .remount_fs = pstore_remount,
.show_options = pstore_show_options,
};
@@ -406,8 +408,9 @@ void pstore_get_records(int quiet)
inode_unlock(d_inode(root));
}
-static int pstore_fill_super(struct super_block *sb, void *data, int silent)
+static int pstore_fill_super(struct super_block *sb, struct fs_context *fc)
{
+ struct pstore_context *ctx = fc->fs_private;
struct inode *inode;
sb->s_maxbytes = MAX_LFS_FILESIZE;
@@ -417,7 +420,7 @@ static int pstore_fill_super(struct super_block *sb, void *data, int silent)
sb->s_op = &pstore_ops;
sb->s_time_gran = 1;
- parse_options(data);
+ pstore_set_kmsg_bytes(ctx->kmsg_bytes);
inode = pstore_get_inode(sb);
if (inode) {
@@ -431,19 +434,33 @@ static int pstore_fill_super(struct super_block *sb, void *data, int silent)
return -ENOMEM;
scoped_guard(mutex, &pstore_sb_lock)
- pstore_sb = sb;
+ pstore_sb = sb;
pstore_get_records(0);
return 0;
}
-static struct dentry *pstore_mount(struct file_system_type *fs_type,
- int flags, const char *dev_name, void *data)
+static int pstore_get_tree(struct fs_context *fc)
+{
+ if (fc->root)
+ return pstore_reconfigure(fc);
+
+ return get_tree_single(fc, pstore_fill_super);
+}
+
+static void pstore_free_fc(struct fs_context *fc)
{
- return mount_single(fs_type, flags, data, pstore_fill_super);
+ kfree(fc->fs_private);
}
+static const struct fs_context_operations pstore_context_ops = {
+ .parse_param = pstore_parse_param,
+ .get_tree = pstore_get_tree,
+ .reconfigure = pstore_reconfigure,
+ .free = pstore_free_fc,
+};
+
static void pstore_kill_sb(struct super_block *sb)
{
guard(mutex)(&pstore_sb_lock);
@@ -456,11 +473,33 @@ static void pstore_kill_sb(struct super_block *sb)
INIT_LIST_HEAD(&records_list);
}
+static int pstore_init_fs_context(struct fs_context *fc)
+{
+ struct pstore_context *ctx;
+
+ ctx = kzalloc(sizeof(struct pstore_context), GFP_KERNEL);
+ if (!ctx)
+ return -ENOMEM;
+
+ /*
+ * Global kmsg_bytes is initialized to default, and updated
+ * every time we (re)mount the single-sb filesystem with the
+ * option specified.
+ */
+ ctx->kmsg_bytes = kmsg_bytes;
+
+ fc->fs_private = ctx;
+ fc->ops = &pstore_context_ops;
+
+ return 0;
+}
+
static struct file_system_type pstore_fs_type = {
.owner = THIS_MODULE,
.name = "pstore",
- .mount = pstore_mount,
.kill_sb = pstore_kill_sb,
+ .init_fs_context = pstore_init_fs_context,
+ .parameters = pstore_param_spec,
};
int __init pstore_init_fs(void)
--
2.48.0
