[RFC PATCH 4/6] jffs2: Convert to fs_context

David Howells
2019-03-21T11:51:01Z

Signed-off-by: David Howells <dhowells@redhat.com>
cc: David Woodhouse <dwmw2@infradead.org>
cc: linux-mtd@lists.infradead.org
---

fs/jffs2/fs.c | 21 +++---
fs/jffs2/os-linux.h | 4 +
fs/jffs2/super.c | 172 +++++++++++++++++++++++++--------------------------
3 files changed, 96 insertions(+), 101 deletions(-)

diff --git a/fs/jffs2/fs.c b/fs/jffs2/fs.c
index eab04eca95a3..d79734bd7650 100644
--- a/fs/jffs2/fs.c
+++ b/fs/jffs2/fs.c
@@ -17,6 +17,7 @@
#include <linux/sched.h>
#include <linux/cred.h>
#include <linux/fs.h>
+#include <linux/fs_context.h>
#include <linux/list.h>
#include <linux/mtd/mtd.h>
#include <linux/pagemap.h>
@@ -184,7 +185,7 @@ int jffs2_do_setattr (struct inode *inode, struct iattr *iattr)
if (ivalid & ATTR_SIZE && inode->i_size > iattr->ia_size) {
truncate_setsize(inode, iattr->ia_size);
inode->i_blocks = (inode->i_size + 511) >> 9;
- }
+ }

return 0;
}
@@ -390,7 +391,7 @@ void jffs2_dirty_inode(struct inode *inode, int flags)
jffs2_do_setattr(inode, &iattr);
}

-int jffs2_do_remount_fs(struct super_block *sb, int *flags, char *data)
+int jffs2_do_remount_fs(struct super_block *sb, struct fs_context *fc)
{
struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);

@@ -408,10 +409,10 @@ int jffs2_do_remount_fs(struct super_block *sb, int *flags, char *data)
mutex_unlock(&c->alloc_sem);
}

- if (!(*flags & SB_RDONLY))
+ if (!(fc->sb_flags & SB_RDONLY))
jffs2_start_garbage_collect_thread(c);

- *flags |= SB_NOATIME;
+ fc->sb_flags |= SB_NOATIME;
return 0;
}

@@ -508,7 +509,7 @@ static int calculate_inocache_hashsize(uint32_t flash_size)
return hashsize;
}

-int jffs2_do_fill_super(struct super_block *sb, void *data, int silent)
+int jffs2_do_fill_super(struct super_block *sb, struct fs_context *fc)
{
struct jffs2_sb_info *c;
struct inode *root_i;
@@ -523,11 +524,11 @@ int jffs2_do_fill_super(struct super_block *sb, void *data, int silent)

#ifndef CONFIG_JFFS2_FS_WRITEBUFFER
if (c->mtd->type == MTD_NANDFLASH) {
- pr_err("Cannot operate on NAND flash unless jffs2 NAND support is compiled in\n");
+ errorf(fc, "Cannot operate on NAND flash unless jffs2 NAND support is compiled in");
return -EINVAL;
}
if (c->mtd->type == MTD_DATAFLASH) {
- pr_err("Cannot operate on DataFlash unless jffs2 DataFlash support is compiled in\n");
+ errorf(fc, "Cannot operate on DataFlash unless jffs2 DataFlash support is compiled in");
return -EINVAL;
}
#endif
@@ -541,12 +542,12 @@ int jffs2_do_fill_super(struct super_block *sb, void *data, int silent)
*/
if ((c->sector_size * blocks) != c->flash_size) {
c->flash_size = c->sector_size * blocks;
- pr_info("Flash size not aligned to erasesize, reducing to %dKiB\n",
- c->flash_size / 1024);
+ infof(fc, "Flash size not aligned to erasesize, reducing to %dKiB",
+ c->flash_size / 1024);
}

if (c->flash_size < 5*c->sector_size) {
- pr_err("Too few erase blocks (%d)\n",
+ errorf(fc, "Too few erase blocks (%d)",
c->flash_size / c->sector_size);
return -EINVAL;
}
diff --git a/fs/jffs2/os-linux.h b/fs/jffs2/os-linux.h
index a2dbbb3f4c74..ac23ae5cdb54 100644
--- a/fs/jffs2/os-linux.h
+++ b/fs/jffs2/os-linux.h
@@ -172,8 +172,8 @@ void jffs2_dirty_inode(struct inode *inode, int flags);
struct inode *jffs2_new_inode (struct inode *dir_i, umode_t mode,
struct jffs2_raw_inode *ri);
int jffs2_statfs (struct dentry *, struct kstatfs *);
-int jffs2_do_remount_fs(struct super_block *, int *, char *);
-int jffs2_do_fill_super(struct super_block *sb, void *data, int silent);
+int jffs2_do_remount_fs(struct super_block *sb, struct fs_context *fc);
+int jffs2_do_fill_super(struct super_block *sb, struct fs_context *fc);
void jffs2_gc_release_inode(struct jffs2_sb_info *c,
struct jffs2_inode_info *f);
struct jffs2_inode_info *jffs2_gc_fetch_inode(struct jffs2_sb_info *c,
diff --git a/fs/jffs2/super.c b/fs/jffs2/super.c
index bb6ae387469f..69dcc4e0b243 100644
--- a/fs/jffs2/super.c
+++ b/fs/jffs2/super.c
@@ -19,7 +19,8 @@
#include <linux/fs.h>
#include <linux/err.h>
#include <linux/mount.h>
-#include <linux/parser.h>
+#include <linux/fs_context.h>
+#include <linux/fs_parser.h>
#include <linux/jffs2.h>
#include <linux/pagemap.h>
#include <linux/mtd/super.h>
@@ -160,96 +161,77 @@ static const struct export_operations jffs2_export_ops = {
/*
* JFFS2 mount options.
*
+ * Opt_source: The source device
* Opt_override_compr: override default compressor
* Opt_rp_size: size of reserved pool in KiB
- * Opt_err: just end of array marker
*/
enum {
+ Opt_source,
Opt_override_compr,
Opt_rp_size,
- Opt_err,
};

-static const match_table_t tokens = {
- {Opt_override_compr, "compr=%s"},
- {Opt_rp_size, "rp_size=%u"},
- {Opt_err, NULL},
+static const struct fs_parameter_spec jffs2_param_specs[] = {
+ fsparam_string ("source", Opt_source),
+ fsparam_enum ("compr", Opt_override_compr),
+ fsparam_u32 ("rp_size", Opt_rp_size),
+ {}
};

-static int jffs2_parse_options(struct jffs2_sb_info *c, char *data)
-{
- substring_t args[MAX_OPT_ARGS];
- char *p, *name;
- unsigned int opt;
-
- if (!data)
- return 0;
-
- while ((p = strsep(&data, ","))) {
- int token;
-
- if (!*p)
- continue;
-
- token = match_token(p, tokens, args);
- switch (token) {
- case Opt_override_compr:
- name = match_strdup(&args[0]);
-
- if (!name)
- return -ENOMEM;
- if (!strcmp(name, "none"))
- c->mount_opts.compr = JFFS2_COMPR_MODE_NONE;
+static const struct fs_parameter_enum jffs2_param_enums[] = {
+ { Opt_override_compr, "none", JFFS2_COMPR_MODE_NONE },
#ifdef CONFIG_JFFS2_LZO
- else if (!strcmp(name, "lzo"))
- c->mount_opts.compr = JFFS2_COMPR_MODE_FORCELZO;
+ { Opt_override_compr, "lzo", JFFS2_COMPR_MODE_FORCELZO },
#endif
#ifdef CONFIG_JFFS2_ZLIB
- else if (!strcmp(name, "zlib"))
- c->mount_opts.compr =
- JFFS2_COMPR_MODE_FORCEZLIB;
+ { Opt_override_compr, "zlib", JFFS2_COMPR_MODE_FORCEZLIB },
#endif
- else {
- pr_err("Error: unknown compressor \"%s\"\n",
- name);
- kfree(name);
- return -EINVAL;
- }
- kfree(name);
- c->mount_opts.override_compr = true;
- break;
- case Opt_rp_size:
- if (match_int(&args[0], &opt))
- return -EINVAL;
- opt *= 1024;
- if (opt > c->mtd->size) {
- pr_warn("Too large reserve pool specified, max "
- "is %llu KB\n", c->mtd->size / 1024);
- return -EINVAL;
- }
- c->mount_opts.rp_size = opt;
- break;
- default:
- pr_err("Error: unrecognized mount option '%s' or missing value\n",
- p);
- return -EINVAL;
- }
+ {}
+};
+
+const struct fs_parameter_description jffs2_fs_parameters = {
+ .name = "jffs2",
+ .specs = jffs2_param_specs,
+ .enums = jffs2_param_enums,
+};
+
+static int jffs2_parse_param(struct fs_context *fc, struct fs_parameter *param)
+{
+ struct fs_parse_result result;
+ struct jffs2_sb_info *c = fc->s_fs_info;
+ int opt;
+
+ opt = fs_parse(fc, &jffs2_fs_parameters, param, &result);
+ if (opt < 0)
+ return opt;
+
+ switch (opt) {
+ case Opt_override_compr:
+ c->mount_opts.compr = result.uint_32;
+ c->mount_opts.override_compr = true;
+ break;
+ case Opt_rp_size:
+ if (result.uint_32 > UINT_MAX / 1024)
+ return invalf(fc, "jffs2: rp_size unrepresentable");
+ opt = result.uint_32 * 1024;
+ if (opt > c->mtd->size)
+ return invalf(fc, "jffs2: Too large reserve pool specified, max is %llu KB",
+ c->mtd->size / 1024);
+ c->mount_opts.rp_size = opt;
+ break;
+ default:
+ return -EINVAL;
}

return 0;
}

-static int jffs2_remount_fs(struct super_block *sb, int *flags, char *data)
+static int jffs2_reconfigure(struct fs_context *fc)
{
- struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
- int err;
+ struct super_block *sb = fc->root->d_sb;

sync_filesystem(sb);
- err = jffs2_parse_options(c, data);
- if (err)
- return -EINVAL;
-
- return jffs2_do_remount_fs(sb, flags, data);
+ return jffs2_do_remount_fs(sb, fc);
}

static const struct super_operations jffs2_super_operations =
@@ -258,7 +240,6 @@ static const struct super_operations jffs2_super_operations =
.destroy_inode =jffs2_destroy_inode,
.put_super = jffs2_put_super,
.statfs = jffs2_statfs,
- .remount_fs = jffs2_remount_fs,
.evict_inode = jffs2_evict_inode,
.dirty_inode = jffs2_dirty_inode,
.show_options = jffs2_show_options,
@@ -268,26 +249,16 @@ static const struct super_operations jffs2_super_operations =
/*
* fill in the superblock
*/
-static int jffs2_fill_super(struct super_block *sb, void *data, int silent)
+static int jffs2_fill_super(struct super_block *sb, struct fs_context *fc)
{
- struct jffs2_sb_info *c;
- int ret;
+ struct jffs2_sb_info *c = sb->s_fs_info;

jffs2_dbg(1, "jffs2_get_sb_mtd():"
" New superblock for device %d (\"%s\")\n",
sb->s_mtd->index, sb->s_mtd->name);

- c = kzalloc(sizeof(*c), GFP_KERNEL);
- if (!c)
- return -ENOMEM;
-
c->mtd = sb->s_mtd;
c->os_priv = sb;
- sb->s_fs_info = c;
-
- ret = jffs2_parse_options(c, data);
- if (ret)
- return -EINVAL;

/* Initialize JFFS2 superblock locks, the further initialization will
* be done later */
@@ -305,15 +276,37 @@ static int jffs2_fill_super(struct super_block *sb, void *data, int silent)
#ifdef CONFIG_JFFS2_FS_POSIX_ACL
sb->s_flags |= SB_POSIXACL;
#endif
- ret = jffs2_do_fill_super(sb, data, silent);
- return ret;
+ return jffs2_do_fill_super(sb, fc);
}

-static struct dentry *jffs2_mount(struct file_system_type *fs_type,
- int flags, const char *dev_name,
- void *data)
+static int jffs2_get_tree(struct fs_context *fc)
{
- return mount_mtd(fs_type, flags, dev_name, data, jffs2_fill_super);
+ return vfs_get_mtd_super(fc, jffs2_fill_super);
+}
+
+static void jffs2_free_fc(struct fs_context *fc)
+{
+ kfree(fc->s_fs_info);
+}
+
+static const struct fs_context_operations jffs2_context_ops = {
+ .free = jffs2_free_fc,
+ .parse_param = jffs2_parse_param,
+ .get_tree = jffs2_get_tree,
+ .reconfigure = jffs2_reconfigure,
+};
+
+static int jffs2_init_fs_context(struct fs_context *fc)
+{
+ struct jffs2_sb_info *ctx;
+
+ ctx = kzalloc(sizeof(struct jffs2_sb_info), GFP_KERNEL);
+ if (!ctx)
+ return -ENOMEM;
+
+ fc->s_fs_info = ctx;
+ fc->ops = &jffs2_context_ops;
+ return 0;
}

static void jffs2_put_super (struct super_block *sb)
@@ -350,7 +343,8 @@ static void jffs2_kill_sb(struct super_block *sb)
static struct file_system_type jffs2_fs_type = {
.owner = THIS_MODULE,
.name = "jffs2",
- .mount = jffs2_mount,
+ .init_fs_context = jffs2_init_fs_context,
+ .parameters = &jffs2_fs_parameters,
.kill_sb = jffs2_kill_sb,
};
MODULE_ALIAS_FS("jffs2");