On Mon, Feb 19, 2024 at 06:33:18PM -0600, Bill O'Donnell wrote:
> Convert the efs filesystem to use the new mount API.
>
> Signed-off-by: Bill O'Donnell <bodonnel@xxxxxxxxxx>
> ---
Thanks for doing this. One question below.
> fs/efs/super.c | 114 ++++++++++++++++++++++++++++++++++++-------------
> 1 file changed, 84 insertions(+), 30 deletions(-)
>
> diff --git a/fs/efs/super.c b/fs/efs/super.c
> index f17fdac76b2e..c837ac89b384 100644
> --- a/fs/efs/super.c
> +++ b/fs/efs/super.c
> @@ -14,19 +14,14 @@
> #include <linux/buffer_head.h>
> #include <linux/vfs.h>
> #include <linux/blkdev.h>
> -
> +#include <linux/fs_context.h>
> +#include <linux/fs_parser.h>
> #include "efs.h"
> #include <linux/efs_vh.h>
> #include <linux/efs_fs_sb.h>
>
> static int efs_statfs(struct dentry *dentry, struct kstatfs *buf);
> -static int efs_fill_super(struct super_block *s, void *d, int silent);
> -
> -static struct dentry *efs_mount(struct file_system_type *fs_type,
> - int flags, const char *dev_name, void *data)
> -{
> - return mount_bdev(fs_type, flags, dev_name, data, efs_fill_super);
> -}
> +static int efs_init_fs_context(struct fs_context *fc);
>
> static void efs_kill_sb(struct super_block *s)
> {
> @@ -35,15 +30,6 @@ static void efs_kill_sb(struct super_block *s)
> kfree(sbi);
> }
>
> -static struct file_system_type efs_fs_type = {
> - .owner = THIS_MODULE,
> - .name = "efs",
> - .mount = efs_mount,
> - .kill_sb = efs_kill_sb,
> - .fs_flags = FS_REQUIRES_DEV,
> -};
> -MODULE_ALIAS_FS("efs");
> -
> static struct pt_types sgi_pt_types[] = {
> {0x00, "SGI vh"},
> {0x01, "SGI trkrepl"},
> @@ -63,6 +49,27 @@ static struct pt_types sgi_pt_types[] = {
> {0, NULL}
> };
>
> +enum {
> + Opt_explicit_open,
> +};
> +
> +static const struct fs_parameter_spec efs_param_spec[] = {
> + fsparam_flag ("explicit-open", Opt_explicit_open),
> + {}
> +};
That looks like it is copy-pasted from zonefs?
> +
> +/*
> + * File system definition and registration.
> + */
> +static struct file_system_type efs_fs_type = {
> + .owner = THIS_MODULE,
> + .name = "efs",
> + .kill_sb = efs_kill_sb,
> + .fs_flags = FS_REQUIRES_DEV,
> + .init_fs_context = efs_init_fs_context,
> + .parameters = efs_param_spec,
> +};
> +MODULE_ALIAS_FS("efs");
>
> static struct kmem_cache * efs_inode_cachep;
>
> @@ -108,18 +115,10 @@ static void destroy_inodecache(void)
> kmem_cache_destroy(efs_inode_cachep);
> }
>
> -static int efs_remount(struct super_block *sb, int *flags, char *data)
> -{
> - sync_filesystem(sb);
> - *flags |= SB_RDONLY;
> - return 0;
> -}
> -
> static const struct super_operations efs_superblock_operations = {
> .alloc_inode = efs_alloc_inode,
> .free_inode = efs_free_inode,
> .statfs = efs_statfs,
> - .remount_fs = efs_remount,
> };
>
> static const struct export_operations efs_export_ops = {
> @@ -249,26 +248,26 @@ static int efs_validate_super(struct efs_sb_info *sb, struct efs_super *super) {
> return 0;
> }
>
> -static int efs_fill_super(struct super_block *s, void *d, int silent)
> +static int efs_fill_super(struct super_block *s, struct fs_context *fc)
> {
> struct efs_sb_info *sb;
> struct buffer_head *bh;
> struct inode *root;
>
> - sb = kzalloc(sizeof(struct efs_sb_info), GFP_KERNEL);
> + sb = kzalloc(sizeof(struct efs_sb_info), GFP_KERNEL);
> if (!sb)
> return -ENOMEM;
> s->s_fs_info = sb;
> s->s_time_min = 0;
> s->s_time_max = U32_MAX;
> -
> +
> s->s_magic = EFS_SUPER_MAGIC;
> if (!sb_set_blocksize(s, EFS_BLOCKSIZE)) {
> pr_err("device does not support %d byte blocks\n",
> EFS_BLOCKSIZE);
> return -EINVAL;
> }
> -
> +
> /* read the vh (volume header) block */
> bh = sb_bread(s, 0);
>
> @@ -294,7 +293,7 @@ static int efs_fill_super(struct super_block *s, void *d, int silent)
> pr_err("cannot read superblock\n");
> return -EIO;
> }
> -
> +
> if (efs_validate_super(sb, (struct efs_super *) bh->b_data)) {
> #ifdef DEBUG
> pr_warn("invalid superblock at block %u\n",
> @@ -328,6 +327,61 @@ static int efs_fill_super(struct super_block *s, void *d, int silent)
> return 0;
> }
>
> +static void efs_free_fc(struct fs_context *fc)
> +{
> + kfree(fc->fs_private);
> +}
> +
> +static int efs_get_tree(struct fs_context *fc)
> +{
> + return get_tree_bdev(fc, efs_fill_super);
> +}
> +
> +static int efs_parse_param(struct fs_context *fc, struct fs_parameter *param)
> +{
> + int token;
> + struct fs_parse_result result;
> +
> + token = fs_parse(fc, efs_param_spec, param, &result);
> + if (token < 0)
> + return token;
Any mount option here is completely ignored, no? Why even have any mount
options then? It's not required to implement ->parse_param.
> + return 0;
> +}
> +
> +static int efs_reconfigure(struct fs_context *fc)
> +{
> + sync_filesystem(fc->root->d_sb);
> +
> + return 0;
> +}
> +
> +struct efs_context {
> + unsigned long s_mount_opts;
> +};
> +
> +static const struct fs_context_operations efs_context_opts = {
> + .parse_param = efs_parse_param,
> + .get_tree = efs_get_tree,
> + .reconfigure = efs_reconfigure,
> + .free = efs_free_fc,
> +};
> +
> +/*
> + * Set up the filesystem mount context.
> + */
> +static int efs_init_fs_context(struct fs_context *fc)
> +{
> + struct efs_context *ctx;
> +
> + ctx = kzalloc(sizeof(struct efs_context), GFP_KERNEL);
> + if (!ctx)
> + return -ENOMEM;
> + fc->fs_private = ctx;
> + fc->ops = &efs_context_opts;
> +
> + return 0;
> +}
> +
> static int efs_statfs(struct dentry *dentry, struct kstatfs *buf) {
> struct super_block *sb = dentry->d_sb;
> struct efs_sb_info *sbi = SUPER_INFO(sb);
> --
> 2.43.2
>
