From c3099e72bf4f5d31f0e0fc725fadcf9397e6aab3 Mon Sep 17 00:00:00 2001 From: Eric Sandeen Date: Mon, 16 Sep 2024 13:26:20 -0400 Subject: [PATCH] befs: convert befs to use the new mount api Convert the befs filesystem to use the new mount API. Tested by comparing random mount & remount options before and after the change. Cc: Luis de Bethencourt Cc: Salah Triki Signed-off-by: Eric Sandeen Link: https://lore.kernel.org/r/20240916172735.866916-4-sandeen@redhat.com Reviewed-by: Jan Kara Signed-off-by: Christian Brauner --- fs/befs/linuxvfs.c | 193 +++++++++++++++++++++++---------------------- 1 file changed, 99 insertions(+), 94 deletions(-) diff --git a/fs/befs/linuxvfs.c b/fs/befs/linuxvfs.c index f92f108840f5..8f430ff8e445 100644 --- a/fs/befs/linuxvfs.c +++ b/fs/befs/linuxvfs.c @@ -11,12 +11,13 @@ #include #include #include +#include +#include #include #include #include #include #include -#include #include #include #include @@ -54,22 +55,20 @@ static int befs_utf2nls(struct super_block *sb, const char *in, int in_len, static int befs_nls2utf(struct super_block *sb, const char *in, int in_len, char **out, int *out_len); static void befs_put_super(struct super_block *); -static int befs_remount(struct super_block *, int *, char *); static int befs_statfs(struct dentry *, struct kstatfs *); static int befs_show_options(struct seq_file *, struct dentry *); -static int parse_options(char *, struct befs_mount_options *); static struct dentry *befs_fh_to_dentry(struct super_block *sb, struct fid *fid, int fh_len, int fh_type); static struct dentry *befs_fh_to_parent(struct super_block *sb, struct fid *fid, int fh_len, int fh_type); static struct dentry *befs_get_parent(struct dentry *child); +static void befs_free_fc(struct fs_context *fc); static const struct super_operations befs_sops = { .alloc_inode = befs_alloc_inode, /* allocate a new inode */ .free_inode = befs_free_inode, /* deallocate an inode */ .put_super = befs_put_super, /* uninit super */ .statfs = befs_statfs, /* statfs */ - .remount_fs = befs_remount, .show_options = befs_show_options, }; @@ -672,92 +671,53 @@ static struct dentry *befs_get_parent(struct dentry *child) } enum { - Opt_uid, Opt_gid, Opt_charset, Opt_debug, Opt_err, + Opt_uid, Opt_gid, Opt_charset, Opt_debug, }; -static const match_table_t befs_tokens = { - {Opt_uid, "uid=%d"}, - {Opt_gid, "gid=%d"}, - {Opt_charset, "iocharset=%s"}, - {Opt_debug, "debug"}, - {Opt_err, NULL} +static const struct fs_parameter_spec befs_param_spec[] = { + fsparam_uid ("uid", Opt_uid), + fsparam_gid ("gid", Opt_gid), + fsparam_string ("iocharset", Opt_charset), + fsparam_flag ("debug", Opt_debug), + {} }; static int -parse_options(char *options, struct befs_mount_options *opts) +befs_parse_param(struct fs_context *fc, struct fs_parameter *param) { - char *p; - substring_t args[MAX_OPT_ARGS]; - int option; - kuid_t uid; - kgid_t gid; + struct befs_mount_options *opts = fc->fs_private; + int token; + struct fs_parse_result result; - /* Initialize options */ - opts->uid = GLOBAL_ROOT_UID; - opts->gid = GLOBAL_ROOT_GID; - opts->use_uid = 0; - opts->use_gid = 0; - opts->iocharset = NULL; - opts->debug = 0; + /* befs ignores all options on remount */ + if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) + return 0; - if (!options) - return 1; + token = fs_parse(fc, befs_param_spec, param, &result); + if (token < 0) + return token; - while ((p = strsep(&options, ",")) != NULL) { - int token; - - if (!*p) - continue; - - token = match_token(p, befs_tokens, args); - switch (token) { - case Opt_uid: - if (match_int(&args[0], &option)) - return 0; - uid = INVALID_UID; - if (option >= 0) - uid = make_kuid(current_user_ns(), option); - if (!uid_valid(uid)) { - pr_err("Invalid uid %d, " - "using default\n", option); - break; - } - opts->uid = uid; - opts->use_uid = 1; - break; - case Opt_gid: - if (match_int(&args[0], &option)) - return 0; - gid = INVALID_GID; - if (option >= 0) - gid = make_kgid(current_user_ns(), option); - if (!gid_valid(gid)) { - pr_err("Invalid gid %d, " - "using default\n", option); - break; - } - opts->gid = gid; - opts->use_gid = 1; - break; - case Opt_charset: - kfree(opts->iocharset); - opts->iocharset = match_strdup(&args[0]); - if (!opts->iocharset) { - pr_err("allocation failure for " - "iocharset string\n"); - return 0; - } - break; - case Opt_debug: - opts->debug = 1; - break; - default: - pr_err("Unrecognized mount option \"%s\" " - "or missing value\n", p); - return 0; - } + switch (token) { + case Opt_uid: + opts->uid = result.uid; + opts->use_uid = 1; + break; + case Opt_gid: + opts->gid = result.gid; + opts->use_gid = 1; + break; + case Opt_charset: + kfree(opts->iocharset); + opts->iocharset = param->string; + param->string = NULL; + break; + case Opt_debug: + opts->debug = 1; + break; + default: + return -EINVAL; } - return 1; + return 0; } static int befs_show_options(struct seq_file *m, struct dentry *root) @@ -793,6 +753,21 @@ befs_put_super(struct super_block *sb) sb->s_fs_info = NULL; } +/* + * Copy the parsed options into the sbi mount_options member + */ +static void +befs_set_options(struct befs_sb_info *sbi, struct befs_mount_options *opts) +{ + sbi->mount_opts.uid = opts->uid; + sbi->mount_opts.gid = opts->gid; + sbi->mount_opts.use_uid = opts->use_uid; + sbi->mount_opts.use_gid = opts->use_gid; + sbi->mount_opts.debug = opts->debug; + sbi->mount_opts.iocharset = opts->iocharset; + opts->iocharset = NULL; +} + /* Allocate private field of the superblock, fill it. * * Finish filling the public superblock fields @@ -800,7 +775,7 @@ befs_put_super(struct super_block *sb) * Load a set of NLS translations if needed. */ static int -befs_fill_super(struct super_block *sb, void *data, int silent) +befs_fill_super(struct super_block *sb, struct fs_context *fc) { struct buffer_head *bh; struct befs_sb_info *befs_sb; @@ -810,6 +785,8 @@ befs_fill_super(struct super_block *sb, void *data, int silent) const unsigned long sb_block = 0; const off_t x86_sb_off = 512; int blocksize; + struct befs_mount_options *parsed_opts = fc->fs_private; + int silent = fc->sb_flags & SB_SILENT; sb->s_fs_info = kzalloc(sizeof(*befs_sb), GFP_KERNEL); if (sb->s_fs_info == NULL) @@ -817,11 +794,7 @@ befs_fill_super(struct super_block *sb, void *data, int silent) befs_sb = BEFS_SB(sb); - if (!parse_options((char *) data, &befs_sb->mount_opts)) { - if (!silent) - befs_error(sb, "cannot parse mount options"); - goto unacquire_priv_sbp; - } + befs_set_options(befs_sb, parsed_opts); befs_debug(sb, "---> %s", __func__); @@ -934,10 +907,10 @@ unacquire_none: } static int -befs_remount(struct super_block *sb, int *flags, char *data) +befs_reconfigure(struct fs_context *fc) { - sync_filesystem(sb); - if (!(*flags & SB_RDONLY)) + sync_filesystem(fc->root->d_sb); + if (!(fc->sb_flags & SB_RDONLY)) return -EINVAL; return 0; } @@ -965,19 +938,51 @@ befs_statfs(struct dentry *dentry, struct kstatfs *buf) return 0; } -static struct dentry * -befs_mount(struct file_system_type *fs_type, int flags, const char *dev_name, - void *data) +static int befs_get_tree(struct fs_context *fc) { - return mount_bdev(fs_type, flags, dev_name, data, befs_fill_super); + return get_tree_bdev(fc, befs_fill_super); +} + +static const struct fs_context_operations befs_context_ops = { + .parse_param = befs_parse_param, + .get_tree = befs_get_tree, + .reconfigure = befs_reconfigure, + .free = befs_free_fc, +}; + +static int befs_init_fs_context(struct fs_context *fc) +{ + struct befs_mount_options *opts; + + opts = kzalloc(sizeof(*opts), GFP_KERNEL); + if (!opts) + return -ENOMEM; + + /* Initialize options */ + opts->uid = GLOBAL_ROOT_UID; + opts->gid = GLOBAL_ROOT_GID; + + fc->fs_private = opts; + fc->ops = &befs_context_ops; + + return 0; +} + +static void befs_free_fc(struct fs_context *fc) +{ + struct befs_mount_options *opts = fc->fs_private; + + kfree(opts->iocharset); + kfree(fc->fs_private); } static struct file_system_type befs_fs_type = { .owner = THIS_MODULE, .name = "befs", - .mount = befs_mount, .kill_sb = kill_block_super, .fs_flags = FS_REQUIRES_DEV, + .init_fs_context = befs_init_fs_context, + .parameters = befs_param_spec, }; MODULE_ALIAS_FS("befs");