lkml.org 
[lkml]   [2019]   [Mar]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Subject[RFC PATCH 4/8] vfs: Convert pstore to fs_context
From
Date
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Kees Cook <keescook@chromium.org>
cc: Anton Vorontsov <anton@enomsg.org>
cc: Colin Cross <ccross@android.com>
cc: Tony Luck <tony.luck@intel.com>
---

fs/pstore/inode.c | 110 ++++++++++++++++++++++++++++++++++-------------------
1 file changed, 71 insertions(+), 39 deletions(-)

diff --git a/fs/pstore/inode.c b/fs/pstore/inode.c
index c60ee46f3e39..4625246fa992 100644
--- a/fs/pstore/inode.c
+++ b/fs/pstore/inode.c
@@ -19,6 +19,8 @@

#include <linux/module.h>
#include <linux/fs.h>
+#include <linux/fs_context.h>
+#include <linux/fs_parser.h>
#include <linux/fsnotify.h>
#include <linux/pagemap.h>
#include <linux/highmem.h>
@@ -26,10 +28,8 @@
#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/sched.h>
#include <linux/magic.h>
#include <linux/pstore.h>
@@ -227,38 +227,48 @@ static struct inode *pstore_get_inode(struct super_block *sb)
return inode;
}

+struct pstore_fs_context {
+ unsigned int kmsg_bytes;
+};
+
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_specs[] = {
+ fsparam_u32 ("kmsg_bytes", Opt_kmsg_bytes),
+ {}
};

-static void parse_options(char *options)
-{
- char *p;
- substring_t args[MAX_OPT_ARGS];
- int option;
+static const struct fs_parameter_description pstore_fs_parameters = {
+ .name = "pstore",
+ .specs = pstore_param_specs,
+};

- if (!options)
- return;
+static int pstore_parse_param(struct fs_context *fc, struct fs_parameter *param)
+{
+ struct pstore_fs_context *ctx = fc->fs_private;
+ struct fs_parse_result result;
+ int opt;
+
+ opt = fs_parse(fc, &pstore_fs_parameters, param, &result);
+ if (opt < 0)
+ return opt;
+
+ switch (opt) {
+ case Opt_kmsg_bytes:
+ ctx->kmsg_bytes = result.uint_32;
+ break;
+ }

- while ((p = strsep(&options, ",")) != NULL) {
- int token;
+ return 0;
+}

- if (!*p)
- continue;
+static void pstore_apply_param(struct fs_context *fc)
+{
+ struct pstore_fs_context *ctx = fc->fs_private;

- token = match_token(p, tokens, args);
- switch (token) {
- case Opt_kmsg_bytes:
- if (!match_int(&args[0], &option))
- pstore_set_kmsg_bytes(option);
- break;
- }
- }
+ pstore_set_kmsg_bytes(ctx->kmsg_bytes);
}

/*
@@ -271,11 +281,10 @@ 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);
-
+ sync_filesystem(fc->root->d_sb);
+ pstore_apply_param(fc);
return 0;
}

@@ -283,7 +292,6 @@ 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,
};

@@ -389,12 +397,10 @@ 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 inode *inode;

- pstore_sb = sb;
-
sb->s_maxbytes = MAX_LFS_FILESIZE;
sb->s_blocksize = PAGE_SIZE;
sb->s_blocksize_bits = PAGE_SHIFT;
@@ -402,7 +408,8 @@ 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_sb = sb;
+ pstore_apply_param(fc);

inode = pstore_get_inode(sb);
if (inode) {
@@ -416,14 +423,38 @@ static int pstore_fill_super(struct super_block *sb, void *data, int silent)
return -ENOMEM;

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)
+{
+ return vfs_get_super(fc, vfs_get_single_reconf_super,
+ 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 = {
+ .free = pstore_free_fc,
+ .parse_param = pstore_parse_param,
+ .get_tree = pstore_get_tree,
+ .reconfigure = pstore_reconfigure,
+};
+
+static int pstore_init_fs_context(struct fs_context *fc)
+{
+ struct pstore_fs_context *ctx;
+
+ ctx = kzalloc(sizeof(struct pstore_fs_context), GFP_KERNEL);
+ if (!ctx)
+ return -ENOMEM;
+
+ fc->fs_private = ctx;
+ fc->ops = &pstore_context_ops;
+ return 0;
}

static void pstore_kill_sb(struct super_block *sb)
@@ -435,7 +466,8 @@ static void pstore_kill_sb(struct super_block *sb)
static struct file_system_type pstore_fs_type = {
.owner = THIS_MODULE,
.name = "pstore",
- .mount = pstore_mount,
+ .init_fs_context = pstore_init_fs_context,
+ .parameters = &pstore_fs_parameters,
.kill_sb = pstore_kill_sb,
};

\
 
 \ /
  Last update: 2019-03-21 12:48    [W:0.100 / U:2.512 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site