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ovl: move all parameter handling into params.{c,h}
While initially I thought that we couldn't move all new mount api
handling into params.{c,h} it turns out it is possible. So this just
moves a good chunk of code out of super.c and into params.{c,h}.
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
This commit is contained in:
Christian Brauner
Amir Goldstein
parent
a901a3568f
commit
7fb7998b59
@ -70,14 +70,6 @@ enum {
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OVL_XINO_ON,
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};
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/* The set of options that user requested explicitly via mount options */
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struct ovl_opt_set {
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bool metacopy;
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bool redirect;
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bool nfs_export;
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bool index;
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};
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/*
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* The tuple (fh,uuid) is a universal unique identifier for a copy up origin,
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* where:
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@ -368,30 +360,6 @@ static inline bool ovl_open_flags_need_copy_up(int flags)
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return ((OPEN_FMODE(flags) & FMODE_WRITE) || (flags & O_TRUNC));
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}
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/* params.c */
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#define OVL_MAX_STACK 500
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struct ovl_fs_context_layer {
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char *name;
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struct path path;
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};
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struct ovl_fs_context {
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struct path upper;
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struct path work;
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size_t capacity;
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size_t nr; /* includes nr_data */
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size_t nr_data;
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struct ovl_opt_set set;
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struct ovl_fs_context_layer *lower;
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};
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int ovl_parse_param_upperdir(const char *name, struct fs_context *fc,
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bool workdir);
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int ovl_parse_param_lowerdir(const char *name, struct fs_context *fc);
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void ovl_parse_param_drop_lowerdir(struct ovl_fs_context *ctx);
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/* util.c */
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int ovl_want_write(struct dentry *dentry);
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void ovl_drop_write(struct dentry *dentry);
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@ -791,3 +759,12 @@ int ovl_set_origin(struct ovl_fs *ofs, struct dentry *lower,
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/* export.c */
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extern const struct export_operations ovl_export_operations;
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/* super.c */
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int ovl_fill_super(struct super_block *sb, struct fs_context *fc);
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/* Will this overlay be forced to mount/remount ro? */
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static inline bool ovl_force_readonly(struct ovl_fs *ofs)
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{
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return (!ovl_upper_mnt(ofs) || !ofs->workdir);
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}
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@ -1,12 +1,124 @@
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// SPDX-License-Identifier: GPL-2.0-only
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#include <linux/fs.h>
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#include <linux/module.h>
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#include <linux/namei.h>
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#include <linux/fs_context.h>
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#include <linux/fs_parser.h>
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#include <linux/posix_acl_xattr.h>
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#include <linux/seq_file.h>
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#include <linux/xattr.h>
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#include "overlayfs.h"
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#include "params.h"
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static bool ovl_redirect_dir_def = IS_ENABLED(CONFIG_OVERLAY_FS_REDIRECT_DIR);
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module_param_named(redirect_dir, ovl_redirect_dir_def, bool, 0644);
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MODULE_PARM_DESC(redirect_dir,
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"Default to on or off for the redirect_dir feature");
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static bool ovl_redirect_always_follow =
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IS_ENABLED(CONFIG_OVERLAY_FS_REDIRECT_ALWAYS_FOLLOW);
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module_param_named(redirect_always_follow, ovl_redirect_always_follow,
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bool, 0644);
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MODULE_PARM_DESC(redirect_always_follow,
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"Follow redirects even if redirect_dir feature is turned off");
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static bool ovl_xino_auto_def = IS_ENABLED(CONFIG_OVERLAY_FS_XINO_AUTO);
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module_param_named(xino_auto, ovl_xino_auto_def, bool, 0644);
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MODULE_PARM_DESC(xino_auto,
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"Auto enable xino feature");
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static bool ovl_index_def = IS_ENABLED(CONFIG_OVERLAY_FS_INDEX);
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module_param_named(index, ovl_index_def, bool, 0644);
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MODULE_PARM_DESC(index,
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"Default to on or off for the inodes index feature");
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static bool ovl_nfs_export_def = IS_ENABLED(CONFIG_OVERLAY_FS_NFS_EXPORT);
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module_param_named(nfs_export, ovl_nfs_export_def, bool, 0644);
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MODULE_PARM_DESC(nfs_export,
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"Default to on or off for the NFS export feature");
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static bool ovl_metacopy_def = IS_ENABLED(CONFIG_OVERLAY_FS_METACOPY);
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module_param_named(metacopy, ovl_metacopy_def, bool, 0644);
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MODULE_PARM_DESC(metacopy,
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"Default to on or off for the metadata only copy up feature");
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enum {
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Opt_lowerdir,
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Opt_upperdir,
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Opt_workdir,
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Opt_default_permissions,
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Opt_redirect_dir,
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Opt_index,
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Opt_uuid,
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Opt_nfs_export,
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Opt_userxattr,
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Opt_xino,
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Opt_metacopy,
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Opt_volatile,
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};
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static const struct constant_table ovl_parameter_bool[] = {
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{ "on", true },
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{ "off", false },
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{}
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};
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static const struct constant_table ovl_parameter_xino[] = {
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{ "off", OVL_XINO_OFF },
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{ "auto", OVL_XINO_AUTO },
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{ "on", OVL_XINO_ON },
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{}
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};
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const char *ovl_xino_mode(struct ovl_config *config)
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{
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return ovl_parameter_xino[config->xino].name;
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}
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static int ovl_xino_def(void)
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{
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return ovl_xino_auto_def ? OVL_XINO_AUTO : OVL_XINO_OFF;
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}
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const struct constant_table ovl_parameter_redirect_dir[] = {
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{ "off", OVL_REDIRECT_OFF },
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{ "follow", OVL_REDIRECT_FOLLOW },
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{ "nofollow", OVL_REDIRECT_NOFOLLOW },
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{ "on", OVL_REDIRECT_ON },
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{}
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};
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static const char *ovl_redirect_mode(struct ovl_config *config)
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{
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return ovl_parameter_redirect_dir[config->redirect_mode].name;
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}
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static int ovl_redirect_mode_def(void)
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{
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return ovl_redirect_dir_def ? OVL_REDIRECT_ON :
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ovl_redirect_always_follow ? OVL_REDIRECT_FOLLOW :
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OVL_REDIRECT_NOFOLLOW;
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}
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#define fsparam_string_empty(NAME, OPT) \
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__fsparam(fs_param_is_string, NAME, OPT, fs_param_can_be_empty, NULL)
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const struct fs_parameter_spec ovl_parameter_spec[] = {
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fsparam_string_empty("lowerdir", Opt_lowerdir),
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fsparam_string("upperdir", Opt_upperdir),
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fsparam_string("workdir", Opt_workdir),
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fsparam_flag("default_permissions", Opt_default_permissions),
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fsparam_enum("redirect_dir", Opt_redirect_dir, ovl_parameter_redirect_dir),
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fsparam_enum("index", Opt_index, ovl_parameter_bool),
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fsparam_enum("uuid", Opt_uuid, ovl_parameter_bool),
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fsparam_enum("nfs_export", Opt_nfs_export, ovl_parameter_bool),
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fsparam_flag("userxattr", Opt_userxattr),
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fsparam_enum("xino", Opt_xino, ovl_parameter_xino),
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fsparam_enum("metacopy", Opt_metacopy, ovl_parameter_bool),
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fsparam_flag("volatile", Opt_volatile),
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{}
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};
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static ssize_t ovl_parse_param_split_lowerdirs(char *str)
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{
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@ -110,8 +222,8 @@ static int ovl_mount_dir(const char *name, struct path *path)
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return err;
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}
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int ovl_parse_param_upperdir(const char *name, struct fs_context *fc,
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bool workdir)
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static int ovl_parse_param_upperdir(const char *name, struct fs_context *fc,
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bool workdir)
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{
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int err;
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struct ovl_fs *ofs = fc->s_fs_info;
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@ -154,7 +266,7 @@ int ovl_parse_param_upperdir(const char *name, struct fs_context *fc,
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return 0;
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}
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void ovl_parse_param_drop_lowerdir(struct ovl_fs_context *ctx)
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static void ovl_parse_param_drop_lowerdir(struct ovl_fs_context *ctx)
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{
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for (size_t nr = 0; nr < ctx->nr; nr++) {
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path_put(&ctx->lower[nr].path);
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@ -179,7 +291,7 @@ void ovl_parse_param_drop_lowerdir(struct ovl_fs_context *ctx)
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* Append data "/lower5" as data lower layer. This requires that
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* there's at least one regular lower layer present.
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*/
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int ovl_parse_param_lowerdir(const char *name, struct fs_context *fc)
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static int ovl_parse_param_lowerdir(const char *name, struct fs_context *fc)
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{
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int err;
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struct ovl_fs_context *ctx = fc->fs_private;
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@ -387,3 +499,415 @@ out_err:
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/* Intentionally don't realloc to a smaller size. */
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return err;
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}
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static int ovl_parse_param(struct fs_context *fc, struct fs_parameter *param)
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{
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int err = 0;
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struct fs_parse_result result;
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struct ovl_fs *ofs = fc->s_fs_info;
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struct ovl_config *config = &ofs->config;
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struct ovl_fs_context *ctx = fc->fs_private;
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int opt;
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if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
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/*
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* On remount overlayfs has always ignored all mount
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* options no matter if malformed or not so for
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* backwards compatibility we do the same here.
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*/
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if (fc->oldapi)
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return 0;
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/*
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* Give us the freedom to allow changing mount options
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* with the new mount api in the future. So instead of
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* silently ignoring everything we report a proper
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* error. This is only visible for users of the new
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* mount api.
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*/
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return invalfc(fc, "No changes allowed in reconfigure");
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}
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opt = fs_parse(fc, ovl_parameter_spec, param, &result);
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if (opt < 0)
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return opt;
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switch (opt) {
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case Opt_lowerdir:
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err = ovl_parse_param_lowerdir(param->string, fc);
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break;
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case Opt_upperdir:
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fallthrough;
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case Opt_workdir:
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err = ovl_parse_param_upperdir(param->string, fc,
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(Opt_workdir == opt));
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break;
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case Opt_default_permissions:
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config->default_permissions = true;
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break;
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case Opt_redirect_dir:
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config->redirect_mode = result.uint_32;
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if (config->redirect_mode == OVL_REDIRECT_OFF) {
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config->redirect_mode = ovl_redirect_always_follow ?
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OVL_REDIRECT_FOLLOW :
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OVL_REDIRECT_NOFOLLOW;
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}
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ctx->set.redirect = true;
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break;
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case Opt_index:
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config->index = result.uint_32;
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ctx->set.index = true;
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break;
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case Opt_uuid:
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config->uuid = result.uint_32;
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break;
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case Opt_nfs_export:
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config->nfs_export = result.uint_32;
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ctx->set.nfs_export = true;
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break;
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case Opt_xino:
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config->xino = result.uint_32;
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break;
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case Opt_metacopy:
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config->metacopy = result.uint_32;
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ctx->set.metacopy = true;
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break;
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case Opt_volatile:
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config->ovl_volatile = true;
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break;
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case Opt_userxattr:
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config->userxattr = true;
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break;
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default:
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pr_err("unrecognized mount option \"%s\" or missing value\n",
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param->key);
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return -EINVAL;
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}
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return err;
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}
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static int ovl_get_tree(struct fs_context *fc)
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{
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return get_tree_nodev(fc, ovl_fill_super);
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}
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static inline void ovl_fs_context_free(struct ovl_fs_context *ctx)
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{
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ovl_parse_param_drop_lowerdir(ctx);
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path_put(&ctx->upper);
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path_put(&ctx->work);
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kfree(ctx->lower);
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kfree(ctx);
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}
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static void ovl_free(struct fs_context *fc)
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{
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struct ovl_fs *ofs = fc->s_fs_info;
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struct ovl_fs_context *ctx = fc->fs_private;
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/*
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* ofs is stored in the fs_context when it is initialized.
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* ofs is transferred to the superblock on a successful mount,
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* but if an error occurs before the transfer we have to free
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* it here.
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*/
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if (ofs)
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ovl_free_fs(ofs);
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if (ctx)
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ovl_fs_context_free(ctx);
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}
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static int ovl_reconfigure(struct fs_context *fc)
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{
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struct super_block *sb = fc->root->d_sb;
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struct ovl_fs *ofs = sb->s_fs_info;
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struct super_block *upper_sb;
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int ret = 0;
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if (!(fc->sb_flags & SB_RDONLY) && ovl_force_readonly(ofs))
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return -EROFS;
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if (fc->sb_flags & SB_RDONLY && !sb_rdonly(sb)) {
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upper_sb = ovl_upper_mnt(ofs)->mnt_sb;
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if (ovl_should_sync(ofs)) {
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down_read(&upper_sb->s_umount);
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ret = sync_filesystem(upper_sb);
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up_read(&upper_sb->s_umount);
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}
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}
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return ret;
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}
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static const struct fs_context_operations ovl_context_ops = {
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.parse_param = ovl_parse_param,
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.get_tree = ovl_get_tree,
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.reconfigure = ovl_reconfigure,
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.free = ovl_free,
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};
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/*
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* This is called during fsopen() and will record the user namespace of
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* the caller in fc->user_ns since we've raised FS_USERNS_MOUNT. We'll
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* need it when we actually create the superblock to verify that the
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* process creating the superblock is in the same user namespace as
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* process that called fsopen().
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*/
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int ovl_init_fs_context(struct fs_context *fc)
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{
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struct ovl_fs_context *ctx;
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struct ovl_fs *ofs;
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ctx = kzalloc(sizeof(*ctx), GFP_KERNEL_ACCOUNT);
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if (!ctx)
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return -ENOMEM;
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/*
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* By default we allocate for three lower layers. It's likely
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* that it'll cover most users.
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*/
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ctx->lower = kmalloc_array(3, sizeof(*ctx->lower), GFP_KERNEL_ACCOUNT);
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if (!ctx->lower)
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goto out_err;
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ctx->capacity = 3;
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ofs = kzalloc(sizeof(struct ovl_fs), GFP_KERNEL);
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if (!ofs)
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goto out_err;
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ofs->config.redirect_mode = ovl_redirect_mode_def();
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ofs->config.index = ovl_index_def;
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ofs->config.uuid = true;
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ofs->config.nfs_export = ovl_nfs_export_def;
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ofs->config.xino = ovl_xino_def();
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ofs->config.metacopy = ovl_metacopy_def;
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fc->s_fs_info = ofs;
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fc->fs_private = ctx;
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fc->ops = &ovl_context_ops;
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return 0;
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out_err:
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ovl_fs_context_free(ctx);
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return -ENOMEM;
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}
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void ovl_free_fs(struct ovl_fs *ofs)
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{
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struct vfsmount **mounts;
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unsigned i;
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iput(ofs->workbasedir_trap);
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iput(ofs->indexdir_trap);
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iput(ofs->workdir_trap);
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dput(ofs->whiteout);
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dput(ofs->indexdir);
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dput(ofs->workdir);
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if (ofs->workdir_locked)
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ovl_inuse_unlock(ofs->workbasedir);
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dput(ofs->workbasedir);
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if (ofs->upperdir_locked)
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ovl_inuse_unlock(ovl_upper_mnt(ofs)->mnt_root);
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/* Hack! Reuse ofs->layers as a vfsmount array before freeing it */
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mounts = (struct vfsmount **) ofs->layers;
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for (i = 0; i < ofs->numlayer; i++) {
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iput(ofs->layers[i].trap);
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mounts[i] = ofs->layers[i].mnt;
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kfree(ofs->layers[i].name);
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}
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kern_unmount_array(mounts, ofs->numlayer);
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kfree(ofs->layers);
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for (i = 0; i < ofs->numfs; i++)
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free_anon_bdev(ofs->fs[i].pseudo_dev);
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kfree(ofs->fs);
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kfree(ofs->config.upperdir);
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kfree(ofs->config.workdir);
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if (ofs->creator_cred)
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put_cred(ofs->creator_cred);
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kfree(ofs);
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}
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int ovl_fs_params_verify(const struct ovl_fs_context *ctx,
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struct ovl_config *config)
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{
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||||
struct ovl_opt_set set = ctx->set;
|
||||
|
||||
if (ctx->nr_data > 0 && !config->metacopy) {
|
||||
pr_err("lower data-only dirs require metacopy support.\n");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
/* Workdir/index are useless in non-upper mount */
|
||||
if (!config->upperdir) {
|
||||
if (config->workdir) {
|
||||
pr_info("option \"workdir=%s\" is useless in a non-upper mount, ignore\n",
|
||||
config->workdir);
|
||||
kfree(config->workdir);
|
||||
config->workdir = NULL;
|
||||
}
|
||||
if (config->index && set.index) {
|
||||
pr_info("option \"index=on\" is useless in a non-upper mount, ignore\n");
|
||||
set.index = false;
|
||||
}
|
||||
config->index = false;
|
||||
}
|
||||
|
||||
if (!config->upperdir && config->ovl_volatile) {
|
||||
pr_info("option \"volatile\" is meaningless in a non-upper mount, ignoring it.\n");
|
||||
config->ovl_volatile = false;
|
||||
}
|
||||
|
||||
/*
|
||||
* This is to make the logic below simpler. It doesn't make any other
|
||||
* difference, since redirect_dir=on is only used for upper.
|
||||
*/
|
||||
if (!config->upperdir && config->redirect_mode == OVL_REDIRECT_FOLLOW)
|
||||
config->redirect_mode = OVL_REDIRECT_ON;
|
||||
|
||||
/* Resolve metacopy -> redirect_dir dependency */
|
||||
if (config->metacopy && config->redirect_mode != OVL_REDIRECT_ON) {
|
||||
if (set.metacopy && set.redirect) {
|
||||
pr_err("conflicting options: metacopy=on,redirect_dir=%s\n",
|
||||
ovl_redirect_mode(config));
|
||||
return -EINVAL;
|
||||
}
|
||||
if (set.redirect) {
|
||||
/*
|
||||
* There was an explicit redirect_dir=... that resulted
|
||||
* in this conflict.
|
||||
*/
|
||||
pr_info("disabling metacopy due to redirect_dir=%s\n",
|
||||
ovl_redirect_mode(config));
|
||||
config->metacopy = false;
|
||||
} else {
|
||||
/* Automatically enable redirect otherwise. */
|
||||
config->redirect_mode = OVL_REDIRECT_ON;
|
||||
}
|
||||
}
|
||||
|
||||
/* Resolve nfs_export -> index dependency */
|
||||
if (config->nfs_export && !config->index) {
|
||||
if (!config->upperdir &&
|
||||
config->redirect_mode != OVL_REDIRECT_NOFOLLOW) {
|
||||
pr_info("NFS export requires \"redirect_dir=nofollow\" on non-upper mount, falling back to nfs_export=off.\n");
|
||||
config->nfs_export = false;
|
||||
} else if (set.nfs_export && set.index) {
|
||||
pr_err("conflicting options: nfs_export=on,index=off\n");
|
||||
return -EINVAL;
|
||||
} else if (set.index) {
|
||||
/*
|
||||
* There was an explicit index=off that resulted
|
||||
* in this conflict.
|
||||
*/
|
||||
pr_info("disabling nfs_export due to index=off\n");
|
||||
config->nfs_export = false;
|
||||
} else {
|
||||
/* Automatically enable index otherwise. */
|
||||
config->index = true;
|
||||
}
|
||||
}
|
||||
|
||||
/* Resolve nfs_export -> !metacopy dependency */
|
||||
if (config->nfs_export && config->metacopy) {
|
||||
if (set.nfs_export && set.metacopy) {
|
||||
pr_err("conflicting options: nfs_export=on,metacopy=on\n");
|
||||
return -EINVAL;
|
||||
}
|
||||
if (set.metacopy) {
|
||||
/*
|
||||
* There was an explicit metacopy=on that resulted
|
||||
* in this conflict.
|
||||
*/
|
||||
pr_info("disabling nfs_export due to metacopy=on\n");
|
||||
config->nfs_export = false;
|
||||
} else {
|
||||
/*
|
||||
* There was an explicit nfs_export=on that resulted
|
||||
* in this conflict.
|
||||
*/
|
||||
pr_info("disabling metacopy due to nfs_export=on\n");
|
||||
config->metacopy = false;
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
/* Resolve userxattr -> !redirect && !metacopy dependency */
|
||||
if (config->userxattr) {
|
||||
if (set.redirect &&
|
||||
config->redirect_mode != OVL_REDIRECT_NOFOLLOW) {
|
||||
pr_err("conflicting options: userxattr,redirect_dir=%s\n",
|
||||
ovl_redirect_mode(config));
|
||||
return -EINVAL;
|
||||
}
|
||||
if (config->metacopy && set.metacopy) {
|
||||
pr_err("conflicting options: userxattr,metacopy=on\n");
|
||||
return -EINVAL;
|
||||
}
|
||||
/*
|
||||
* Silently disable default setting of redirect and metacopy.
|
||||
* This shall be the default in the future as well: these
|
||||
* options must be explicitly enabled if used together with
|
||||
* userxattr.
|
||||
*/
|
||||
config->redirect_mode = OVL_REDIRECT_NOFOLLOW;
|
||||
config->metacopy = false;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* ovl_show_options
|
||||
* @m: the seq_file handle
|
||||
* @dentry: The dentry to query
|
||||
*
|
||||
* Prints the mount options for a given superblock.
|
||||
* Returns zero; does not fail.
|
||||
*/
|
||||
int ovl_show_options(struct seq_file *m, struct dentry *dentry)
|
||||
{
|
||||
struct super_block *sb = dentry->d_sb;
|
||||
struct ovl_fs *ofs = sb->s_fs_info;
|
||||
size_t nr, nr_merged_lower = ofs->numlayer - ofs->numdatalayer;
|
||||
const struct ovl_layer *data_layers = &ofs->layers[nr_merged_lower];
|
||||
|
||||
/* ofs->layers[0] is the upper layer */
|
||||
seq_printf(m, ",lowerdir=%s", ofs->layers[1].name);
|
||||
/* dump regular lower layers */
|
||||
for (nr = 2; nr < nr_merged_lower; nr++)
|
||||
seq_printf(m, ":%s", ofs->layers[nr].name);
|
||||
/* dump data lower layers */
|
||||
for (nr = 0; nr < ofs->numdatalayer; nr++)
|
||||
seq_printf(m, "::%s", data_layers[nr].name);
|
||||
if (ofs->config.upperdir) {
|
||||
seq_show_option(m, "upperdir", ofs->config.upperdir);
|
||||
seq_show_option(m, "workdir", ofs->config.workdir);
|
||||
}
|
||||
if (ofs->config.default_permissions)
|
||||
seq_puts(m, ",default_permissions");
|
||||
if (ofs->config.redirect_mode != ovl_redirect_mode_def())
|
||||
seq_printf(m, ",redirect_dir=%s",
|
||||
ovl_redirect_mode(&ofs->config));
|
||||
if (ofs->config.index != ovl_index_def)
|
||||
seq_printf(m, ",index=%s", ofs->config.index ? "on" : "off");
|
||||
if (!ofs->config.uuid)
|
||||
seq_puts(m, ",uuid=off");
|
||||
if (ofs->config.nfs_export != ovl_nfs_export_def)
|
||||
seq_printf(m, ",nfs_export=%s", ofs->config.nfs_export ?
|
||||
"on" : "off");
|
||||
if (ofs->config.xino != ovl_xino_def() && !ovl_same_fs(ofs))
|
||||
seq_printf(m, ",xino=%s", ovl_xino_mode(&ofs->config));
|
||||
if (ofs->config.metacopy != ovl_metacopy_def)
|
||||
seq_printf(m, ",metacopy=%s",
|
||||
ofs->config.metacopy ? "on" : "off");
|
||||
if (ofs->config.ovl_volatile)
|
||||
seq_puts(m, ",volatile");
|
||||
if (ofs->config.userxattr)
|
||||
seq_puts(m, ",userxattr");
|
||||
return 0;
|
||||
}
|
||||
|
||||
42
fs/overlayfs/params.h
Normal file
42
fs/overlayfs/params.h
Normal file
@ -0,0 +1,42 @@
|
||||
/* SPDX-License-Identifier: GPL-2.0-only */
|
||||
|
||||
#include <linux/fs_context.h>
|
||||
#include <linux/fs_parser.h>
|
||||
|
||||
struct ovl_fs;
|
||||
struct ovl_config;
|
||||
|
||||
extern const struct fs_parameter_spec ovl_parameter_spec[];
|
||||
extern const struct constant_table ovl_parameter_redirect_dir[];
|
||||
|
||||
/* The set of options that user requested explicitly via mount options */
|
||||
struct ovl_opt_set {
|
||||
bool metacopy;
|
||||
bool redirect;
|
||||
bool nfs_export;
|
||||
bool index;
|
||||
};
|
||||
|
||||
#define OVL_MAX_STACK 500
|
||||
|
||||
struct ovl_fs_context_layer {
|
||||
char *name;
|
||||
struct path path;
|
||||
};
|
||||
|
||||
struct ovl_fs_context {
|
||||
struct path upper;
|
||||
struct path work;
|
||||
size_t capacity;
|
||||
size_t nr; /* includes nr_data */
|
||||
size_t nr_data;
|
||||
struct ovl_opt_set set;
|
||||
struct ovl_fs_context_layer *lower;
|
||||
};
|
||||
|
||||
int ovl_init_fs_context(struct fs_context *fc);
|
||||
void ovl_free_fs(struct ovl_fs *ofs);
|
||||
int ovl_fs_params_verify(const struct ovl_fs_context *ctx,
|
||||
struct ovl_config *config);
|
||||
int ovl_show_options(struct seq_file *m, struct dentry *dentry);
|
||||
const char *ovl_xino_mode(struct ovl_config *config);
|
||||
@ -19,6 +19,7 @@
|
||||
#include <linux/fs_context.h>
|
||||
#include <linux/fs_parser.h>
|
||||
#include "overlayfs.h"
|
||||
#include "params.h"
|
||||
|
||||
MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>");
|
||||
MODULE_DESCRIPTION("Overlay filesystem");
|
||||
@ -27,38 +28,6 @@ MODULE_LICENSE("GPL");
|
||||
|
||||
struct ovl_dir_cache;
|
||||
|
||||
static bool ovl_redirect_dir_def = IS_ENABLED(CONFIG_OVERLAY_FS_REDIRECT_DIR);
|
||||
module_param_named(redirect_dir, ovl_redirect_dir_def, bool, 0644);
|
||||
MODULE_PARM_DESC(redirect_dir,
|
||||
"Default to on or off for the redirect_dir feature");
|
||||
|
||||
static bool ovl_redirect_always_follow =
|
||||
IS_ENABLED(CONFIG_OVERLAY_FS_REDIRECT_ALWAYS_FOLLOW);
|
||||
module_param_named(redirect_always_follow, ovl_redirect_always_follow,
|
||||
bool, 0644);
|
||||
MODULE_PARM_DESC(redirect_always_follow,
|
||||
"Follow redirects even if redirect_dir feature is turned off");
|
||||
|
||||
static bool ovl_index_def = IS_ENABLED(CONFIG_OVERLAY_FS_INDEX);
|
||||
module_param_named(index, ovl_index_def, bool, 0644);
|
||||
MODULE_PARM_DESC(index,
|
||||
"Default to on or off for the inodes index feature");
|
||||
|
||||
static bool ovl_nfs_export_def = IS_ENABLED(CONFIG_OVERLAY_FS_NFS_EXPORT);
|
||||
module_param_named(nfs_export, ovl_nfs_export_def, bool, 0644);
|
||||
MODULE_PARM_DESC(nfs_export,
|
||||
"Default to on or off for the NFS export feature");
|
||||
|
||||
static bool ovl_xino_auto_def = IS_ENABLED(CONFIG_OVERLAY_FS_XINO_AUTO);
|
||||
module_param_named(xino_auto, ovl_xino_auto_def, bool, 0644);
|
||||
MODULE_PARM_DESC(xino_auto,
|
||||
"Auto enable xino feature");
|
||||
|
||||
static bool ovl_metacopy_def = IS_ENABLED(CONFIG_OVERLAY_FS_METACOPY);
|
||||
module_param_named(metacopy, ovl_metacopy_def, bool, 0644);
|
||||
MODULE_PARM_DESC(metacopy,
|
||||
"Default to on or off for the metadata only copy up feature");
|
||||
|
||||
static struct dentry *ovl_d_real(struct dentry *dentry,
|
||||
const struct inode *inode)
|
||||
{
|
||||
@ -211,43 +180,6 @@ static void ovl_destroy_inode(struct inode *inode)
|
||||
kfree(oi->lowerdata_redirect);
|
||||
}
|
||||
|
||||
static void ovl_free_fs(struct ovl_fs *ofs)
|
||||
{
|
||||
struct vfsmount **mounts;
|
||||
unsigned i;
|
||||
|
||||
iput(ofs->workbasedir_trap);
|
||||
iput(ofs->indexdir_trap);
|
||||
iput(ofs->workdir_trap);
|
||||
dput(ofs->whiteout);
|
||||
dput(ofs->indexdir);
|
||||
dput(ofs->workdir);
|
||||
if (ofs->workdir_locked)
|
||||
ovl_inuse_unlock(ofs->workbasedir);
|
||||
dput(ofs->workbasedir);
|
||||
if (ofs->upperdir_locked)
|
||||
ovl_inuse_unlock(ovl_upper_mnt(ofs)->mnt_root);
|
||||
|
||||
/* Hack! Reuse ofs->layers as a vfsmount array before freeing it */
|
||||
mounts = (struct vfsmount **) ofs->layers;
|
||||
for (i = 0; i < ofs->numlayer; i++) {
|
||||
iput(ofs->layers[i].trap);
|
||||
mounts[i] = ofs->layers[i].mnt;
|
||||
kfree(ofs->layers[i].name);
|
||||
}
|
||||
kern_unmount_array(mounts, ofs->numlayer);
|
||||
kfree(ofs->layers);
|
||||
for (i = 0; i < ofs->numfs; i++)
|
||||
free_anon_bdev(ofs->fs[i].pseudo_dev);
|
||||
kfree(ofs->fs);
|
||||
|
||||
kfree(ofs->config.upperdir);
|
||||
kfree(ofs->config.workdir);
|
||||
if (ofs->creator_cred)
|
||||
put_cred(ofs->creator_cred);
|
||||
kfree(ofs);
|
||||
}
|
||||
|
||||
static void ovl_put_super(struct super_block *sb)
|
||||
{
|
||||
struct ovl_fs *ofs = sb->s_fs_info;
|
||||
@ -323,122 +255,6 @@ static int ovl_statfs(struct dentry *dentry, struct kstatfs *buf)
|
||||
return err;
|
||||
}
|
||||
|
||||
/* Will this overlay be forced to mount/remount ro? */
|
||||
static bool ovl_force_readonly(struct ovl_fs *ofs)
|
||||
{
|
||||
return (!ovl_upper_mnt(ofs) || !ofs->workdir);
|
||||
}
|
||||
|
||||
static const struct constant_table ovl_parameter_redirect_dir[] = {
|
||||
{ "off", OVL_REDIRECT_OFF },
|
||||
{ "follow", OVL_REDIRECT_FOLLOW },
|
||||
{ "nofollow", OVL_REDIRECT_NOFOLLOW },
|
||||
{ "on", OVL_REDIRECT_ON },
|
||||
{}
|
||||
};
|
||||
|
||||
static const char *ovl_redirect_mode(struct ovl_config *config)
|
||||
{
|
||||
return ovl_parameter_redirect_dir[config->redirect_mode].name;
|
||||
}
|
||||
|
||||
static int ovl_redirect_mode_def(void)
|
||||
{
|
||||
return ovl_redirect_dir_def ? OVL_REDIRECT_ON :
|
||||
ovl_redirect_always_follow ? OVL_REDIRECT_FOLLOW :
|
||||
OVL_REDIRECT_NOFOLLOW;
|
||||
}
|
||||
|
||||
static const struct constant_table ovl_parameter_xino[] = {
|
||||
{ "off", OVL_XINO_OFF },
|
||||
{ "auto", OVL_XINO_AUTO },
|
||||
{ "on", OVL_XINO_ON },
|
||||
{}
|
||||
};
|
||||
|
||||
static const char *ovl_xino_mode(struct ovl_config *config)
|
||||
{
|
||||
return ovl_parameter_xino[config->xino].name;
|
||||
}
|
||||
|
||||
static inline int ovl_xino_def(void)
|
||||
{
|
||||
return ovl_xino_auto_def ? OVL_XINO_AUTO : OVL_XINO_OFF;
|
||||
}
|
||||
|
||||
/**
|
||||
* ovl_show_options
|
||||
* @m: the seq_file handle
|
||||
* @dentry: The dentry to query
|
||||
*
|
||||
* Prints the mount options for a given superblock.
|
||||
* Returns zero; does not fail.
|
||||
*/
|
||||
static int ovl_show_options(struct seq_file *m, struct dentry *dentry)
|
||||
{
|
||||
struct super_block *sb = dentry->d_sb;
|
||||
struct ovl_fs *ofs = sb->s_fs_info;
|
||||
size_t nr, nr_merged_lower = ofs->numlayer - ofs->numdatalayer;
|
||||
const struct ovl_layer *data_layers = &ofs->layers[nr_merged_lower];
|
||||
|
||||
/* ofs->layers[0] is the upper layer */
|
||||
seq_printf(m, ",lowerdir=%s", ofs->layers[1].name);
|
||||
/* dump regular lower layers */
|
||||
for (nr = 2; nr < nr_merged_lower; nr++)
|
||||
seq_printf(m, ":%s", ofs->layers[nr].name);
|
||||
/* dump data lower layers */
|
||||
for (nr = 0; nr < ofs->numdatalayer; nr++)
|
||||
seq_printf(m, "::%s", data_layers[nr].name);
|
||||
if (ofs->config.upperdir) {
|
||||
seq_show_option(m, "upperdir", ofs->config.upperdir);
|
||||
seq_show_option(m, "workdir", ofs->config.workdir);
|
||||
}
|
||||
if (ofs->config.default_permissions)
|
||||
seq_puts(m, ",default_permissions");
|
||||
if (ofs->config.redirect_mode != ovl_redirect_mode_def())
|
||||
seq_printf(m, ",redirect_dir=%s",
|
||||
ovl_redirect_mode(&ofs->config));
|
||||
if (ofs->config.index != ovl_index_def)
|
||||
seq_printf(m, ",index=%s", ofs->config.index ? "on" : "off");
|
||||
if (!ofs->config.uuid)
|
||||
seq_puts(m, ",uuid=off");
|
||||
if (ofs->config.nfs_export != ovl_nfs_export_def)
|
||||
seq_printf(m, ",nfs_export=%s", ofs->config.nfs_export ?
|
||||
"on" : "off");
|
||||
if (ofs->config.xino != ovl_xino_def() && !ovl_same_fs(ofs))
|
||||
seq_printf(m, ",xino=%s", ovl_xino_mode(&ofs->config));
|
||||
if (ofs->config.metacopy != ovl_metacopy_def)
|
||||
seq_printf(m, ",metacopy=%s",
|
||||
ofs->config.metacopy ? "on" : "off");
|
||||
if (ofs->config.ovl_volatile)
|
||||
seq_puts(m, ",volatile");
|
||||
if (ofs->config.userxattr)
|
||||
seq_puts(m, ",userxattr");
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int ovl_reconfigure(struct fs_context *fc)
|
||||
{
|
||||
struct super_block *sb = fc->root->d_sb;
|
||||
struct ovl_fs *ofs = sb->s_fs_info;
|
||||
struct super_block *upper_sb;
|
||||
int ret = 0;
|
||||
|
||||
if (!(fc->sb_flags & SB_RDONLY) && ovl_force_readonly(ofs))
|
||||
return -EROFS;
|
||||
|
||||
if (fc->sb_flags & SB_RDONLY && !sb_rdonly(sb)) {
|
||||
upper_sb = ovl_upper_mnt(ofs)->mnt_sb;
|
||||
if (ovl_should_sync(ofs)) {
|
||||
down_read(&upper_sb->s_umount);
|
||||
ret = sync_filesystem(upper_sb);
|
||||
up_read(&upper_sb->s_umount);
|
||||
}
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static const struct super_operations ovl_super_operations = {
|
||||
.alloc_inode = ovl_alloc_inode,
|
||||
.free_inode = ovl_free_inode,
|
||||
@ -450,262 +266,6 @@ static const struct super_operations ovl_super_operations = {
|
||||
.show_options = ovl_show_options,
|
||||
};
|
||||
|
||||
enum {
|
||||
Opt_lowerdir,
|
||||
Opt_upperdir,
|
||||
Opt_workdir,
|
||||
Opt_default_permissions,
|
||||
Opt_redirect_dir,
|
||||
Opt_index,
|
||||
Opt_uuid,
|
||||
Opt_nfs_export,
|
||||
Opt_userxattr,
|
||||
Opt_xino,
|
||||
Opt_metacopy,
|
||||
Opt_volatile,
|
||||
};
|
||||
|
||||
static const struct constant_table ovl_parameter_bool[] = {
|
||||
{ "on", true },
|
||||
{ "off", false },
|
||||
{}
|
||||
};
|
||||
|
||||
#define fsparam_string_empty(NAME, OPT) \
|
||||
__fsparam(fs_param_is_string, NAME, OPT, fs_param_can_be_empty, NULL)
|
||||
|
||||
static const struct fs_parameter_spec ovl_parameter_spec[] = {
|
||||
fsparam_string_empty("lowerdir", Opt_lowerdir),
|
||||
fsparam_string("upperdir", Opt_upperdir),
|
||||
fsparam_string("workdir", Opt_workdir),
|
||||
fsparam_flag("default_permissions", Opt_default_permissions),
|
||||
fsparam_enum("redirect_dir", Opt_redirect_dir, ovl_parameter_redirect_dir),
|
||||
fsparam_enum("index", Opt_index, ovl_parameter_bool),
|
||||
fsparam_enum("uuid", Opt_uuid, ovl_parameter_bool),
|
||||
fsparam_enum("nfs_export", Opt_nfs_export, ovl_parameter_bool),
|
||||
fsparam_flag("userxattr", Opt_userxattr),
|
||||
fsparam_enum("xino", Opt_xino, ovl_parameter_xino),
|
||||
fsparam_enum("metacopy", Opt_metacopy, ovl_parameter_bool),
|
||||
fsparam_flag("volatile", Opt_volatile),
|
||||
{}
|
||||
};
|
||||
|
||||
static int ovl_parse_param(struct fs_context *fc, struct fs_parameter *param)
|
||||
{
|
||||
int err = 0;
|
||||
struct fs_parse_result result;
|
||||
struct ovl_fs *ofs = fc->s_fs_info;
|
||||
struct ovl_config *config = &ofs->config;
|
||||
struct ovl_fs_context *ctx = fc->fs_private;
|
||||
int opt;
|
||||
|
||||
if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
|
||||
/*
|
||||
* On remount overlayfs has always ignored all mount
|
||||
* options no matter if malformed or not so for
|
||||
* backwards compatibility we do the same here.
|
||||
*/
|
||||
if (fc->oldapi)
|
||||
return 0;
|
||||
|
||||
/*
|
||||
* Give us the freedom to allow changing mount options
|
||||
* with the new mount api in the future. So instead of
|
||||
* silently ignoring everything we report a proper
|
||||
* error. This is only visible for users of the new
|
||||
* mount api.
|
||||
*/
|
||||
return invalfc(fc, "No changes allowed in reconfigure");
|
||||
}
|
||||
|
||||
opt = fs_parse(fc, ovl_parameter_spec, param, &result);
|
||||
if (opt < 0)
|
||||
return opt;
|
||||
|
||||
switch (opt) {
|
||||
case Opt_lowerdir:
|
||||
err = ovl_parse_param_lowerdir(param->string, fc);
|
||||
break;
|
||||
case Opt_upperdir:
|
||||
fallthrough;
|
||||
case Opt_workdir:
|
||||
err = ovl_parse_param_upperdir(param->string, fc,
|
||||
(Opt_workdir == opt));
|
||||
break;
|
||||
case Opt_default_permissions:
|
||||
config->default_permissions = true;
|
||||
break;
|
||||
case Opt_redirect_dir:
|
||||
config->redirect_mode = result.uint_32;
|
||||
if (config->redirect_mode == OVL_REDIRECT_OFF) {
|
||||
config->redirect_mode = ovl_redirect_always_follow ?
|
||||
OVL_REDIRECT_FOLLOW :
|
||||
OVL_REDIRECT_NOFOLLOW;
|
||||
}
|
||||
ctx->set.redirect = true;
|
||||
break;
|
||||
case Opt_index:
|
||||
config->index = result.uint_32;
|
||||
ctx->set.index = true;
|
||||
break;
|
||||
case Opt_uuid:
|
||||
config->uuid = result.uint_32;
|
||||
break;
|
||||
case Opt_nfs_export:
|
||||
config->nfs_export = result.uint_32;
|
||||
ctx->set.nfs_export = true;
|
||||
break;
|
||||
case Opt_xino:
|
||||
config->xino = result.uint_32;
|
||||
break;
|
||||
case Opt_metacopy:
|
||||
config->metacopy = result.uint_32;
|
||||
ctx->set.metacopy = true;
|
||||
break;
|
||||
case Opt_volatile:
|
||||
config->ovl_volatile = true;
|
||||
break;
|
||||
case Opt_userxattr:
|
||||
config->userxattr = true;
|
||||
break;
|
||||
default:
|
||||
pr_err("unrecognized mount option \"%s\" or missing value\n",
|
||||
param->key);
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
return err;
|
||||
}
|
||||
|
||||
static int ovl_fs_params_verify(const struct ovl_fs_context *ctx,
|
||||
struct ovl_config *config)
|
||||
{
|
||||
struct ovl_opt_set set = ctx->set;
|
||||
|
||||
if (ctx->nr_data > 0 && !config->metacopy) {
|
||||
pr_err("lower data-only dirs require metacopy support.\n");
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
/* Workdir/index are useless in non-upper mount */
|
||||
if (!config->upperdir) {
|
||||
if (config->workdir) {
|
||||
pr_info("option \"workdir=%s\" is useless in a non-upper mount, ignore\n",
|
||||
config->workdir);
|
||||
kfree(config->workdir);
|
||||
config->workdir = NULL;
|
||||
}
|
||||
if (config->index && set.index) {
|
||||
pr_info("option \"index=on\" is useless in a non-upper mount, ignore\n");
|
||||
set.index = false;
|
||||
}
|
||||
config->index = false;
|
||||
}
|
||||
|
||||
if (!config->upperdir && config->ovl_volatile) {
|
||||
pr_info("option \"volatile\" is meaningless in a non-upper mount, ignoring it.\n");
|
||||
config->ovl_volatile = false;
|
||||
}
|
||||
|
||||
/*
|
||||
* This is to make the logic below simpler. It doesn't make any other
|
||||
* difference, since redirect_dir=on is only used for upper.
|
||||
*/
|
||||
if (!config->upperdir && config->redirect_mode == OVL_REDIRECT_FOLLOW)
|
||||
config->redirect_mode = OVL_REDIRECT_ON;
|
||||
|
||||
/* Resolve metacopy -> redirect_dir dependency */
|
||||
if (config->metacopy && config->redirect_mode != OVL_REDIRECT_ON) {
|
||||
if (set.metacopy && set.redirect) {
|
||||
pr_err("conflicting options: metacopy=on,redirect_dir=%s\n",
|
||||
ovl_redirect_mode(config));
|
||||
return -EINVAL;
|
||||
}
|
||||
if (set.redirect) {
|
||||
/*
|
||||
* There was an explicit redirect_dir=... that resulted
|
||||
* in this conflict.
|
||||
*/
|
||||
pr_info("disabling metacopy due to redirect_dir=%s\n",
|
||||
ovl_redirect_mode(config));
|
||||
config->metacopy = false;
|
||||
} else {
|
||||
/* Automatically enable redirect otherwise. */
|
||||
config->redirect_mode = OVL_REDIRECT_ON;
|
||||
}
|
||||
}
|
||||
|
||||
/* Resolve nfs_export -> index dependency */
|
||||
if (config->nfs_export && !config->index) {
|
||||
if (!config->upperdir &&
|
||||
config->redirect_mode != OVL_REDIRECT_NOFOLLOW) {
|
||||
pr_info("NFS export requires \"redirect_dir=nofollow\" on non-upper mount, falling back to nfs_export=off.\n");
|
||||
config->nfs_export = false;
|
||||
} else if (set.nfs_export && set.index) {
|
||||
pr_err("conflicting options: nfs_export=on,index=off\n");
|
||||
return -EINVAL;
|
||||
} else if (set.index) {
|
||||
/*
|
||||
* There was an explicit index=off that resulted
|
||||
* in this conflict.
|
||||
*/
|
||||
pr_info("disabling nfs_export due to index=off\n");
|
||||
config->nfs_export = false;
|
||||
} else {
|
||||
/* Automatically enable index otherwise. */
|
||||
config->index = true;
|
||||
}
|
||||
}
|
||||
|
||||
/* Resolve nfs_export -> !metacopy dependency */
|
||||
if (config->nfs_export && config->metacopy) {
|
||||
if (set.nfs_export && set.metacopy) {
|
||||
pr_err("conflicting options: nfs_export=on,metacopy=on\n");
|
||||
return -EINVAL;
|
||||
}
|
||||
if (set.metacopy) {
|
||||
/*
|
||||
* There was an explicit metacopy=on that resulted
|
||||
* in this conflict.
|
||||
*/
|
||||
pr_info("disabling nfs_export due to metacopy=on\n");
|
||||
config->nfs_export = false;
|
||||
} else {
|
||||
/*
|
||||
* There was an explicit nfs_export=on that resulted
|
||||
* in this conflict.
|
||||
*/
|
||||
pr_info("disabling metacopy due to nfs_export=on\n");
|
||||
config->metacopy = false;
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
/* Resolve userxattr -> !redirect && !metacopy dependency */
|
||||
if (config->userxattr) {
|
||||
if (set.redirect &&
|
||||
config->redirect_mode != OVL_REDIRECT_NOFOLLOW) {
|
||||
pr_err("conflicting options: userxattr,redirect_dir=%s\n",
|
||||
ovl_redirect_mode(config));
|
||||
return -EINVAL;
|
||||
}
|
||||
if (config->metacopy && set.metacopy) {
|
||||
pr_err("conflicting options: userxattr,metacopy=on\n");
|
||||
return -EINVAL;
|
||||
}
|
||||
/*
|
||||
* Silently disable default setting of redirect and metacopy.
|
||||
* This shall be the default in the future as well: these
|
||||
* options must be explicitly enabled if used together with
|
||||
* userxattr.
|
||||
*/
|
||||
config->redirect_mode = OVL_REDIRECT_NOFOLLOW;
|
||||
config->metacopy = false;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
#define OVL_WORKDIR_NAME "work"
|
||||
#define OVL_INDEXDIR_NAME "index"
|
||||
|
||||
@ -1758,7 +1318,7 @@ static struct dentry *ovl_get_root(struct super_block *sb,
|
||||
return root;
|
||||
}
|
||||
|
||||
static int ovl_fill_super(struct super_block *sb, struct fs_context *fc)
|
||||
int ovl_fill_super(struct super_block *sb, struct fs_context *fc)
|
||||
{
|
||||
struct ovl_fs *ofs = sb->s_fs_info;
|
||||
struct ovl_fs_context *ctx = fc->fs_private;
|
||||
@ -1919,92 +1479,6 @@ out_err:
|
||||
return err;
|
||||
}
|
||||
|
||||
static int ovl_get_tree(struct fs_context *fc)
|
||||
{
|
||||
return get_tree_nodev(fc, ovl_fill_super);
|
||||
}
|
||||
|
||||
static inline void ovl_fs_context_free(struct ovl_fs_context *ctx)
|
||||
{
|
||||
ovl_parse_param_drop_lowerdir(ctx);
|
||||
path_put(&ctx->upper);
|
||||
path_put(&ctx->work);
|
||||
kfree(ctx->lower);
|
||||
kfree(ctx);
|
||||
}
|
||||
|
||||
static void ovl_free(struct fs_context *fc)
|
||||
{
|
||||
struct ovl_fs *ofs = fc->s_fs_info;
|
||||
struct ovl_fs_context *ctx = fc->fs_private;
|
||||
|
||||
/*
|
||||
* ofs is stored in the fs_context when it is initialized.
|
||||
* ofs is transferred to the superblock on a successful mount,
|
||||
* but if an error occurs before the transfer we have to free
|
||||
* it here.
|
||||
*/
|
||||
if (ofs)
|
||||
ovl_free_fs(ofs);
|
||||
|
||||
if (ctx)
|
||||
ovl_fs_context_free(ctx);
|
||||
}
|
||||
|
||||
static const struct fs_context_operations ovl_context_ops = {
|
||||
.parse_param = ovl_parse_param,
|
||||
.get_tree = ovl_get_tree,
|
||||
.reconfigure = ovl_reconfigure,
|
||||
.free = ovl_free,
|
||||
};
|
||||
|
||||
/*
|
||||
* This is called during fsopen() and will record the user namespace of
|
||||
* the caller in fc->user_ns since we've raised FS_USERNS_MOUNT. We'll
|
||||
* need it when we actually create the superblock to verify that the
|
||||
* process creating the superblock is in the same user namespace as
|
||||
* process that called fsopen().
|
||||
*/
|
||||
static int ovl_init_fs_context(struct fs_context *fc)
|
||||
{
|
||||
struct ovl_fs_context *ctx;
|
||||
struct ovl_fs *ofs;
|
||||
|
||||
ctx = kzalloc(sizeof(*ctx), GFP_KERNEL_ACCOUNT);
|
||||
if (!ctx)
|
||||
return -ENOMEM;
|
||||
|
||||
/*
|
||||
* By default we allocate for three lower layers. It's likely
|
||||
* that it'll cover most users.
|
||||
*/
|
||||
ctx->lower = kmalloc_array(3, sizeof(*ctx->lower), GFP_KERNEL_ACCOUNT);
|
||||
if (!ctx->lower)
|
||||
goto out_err;
|
||||
ctx->capacity = 3;
|
||||
|
||||
ofs = kzalloc(sizeof(struct ovl_fs), GFP_KERNEL);
|
||||
if (!ofs)
|
||||
goto out_err;
|
||||
|
||||
ofs->config.redirect_mode = ovl_redirect_mode_def();
|
||||
ofs->config.index = ovl_index_def;
|
||||
ofs->config.uuid = true;
|
||||
ofs->config.nfs_export = ovl_nfs_export_def;
|
||||
ofs->config.xino = ovl_xino_def();
|
||||
ofs->config.metacopy = ovl_metacopy_def;
|
||||
|
||||
fc->s_fs_info = ofs;
|
||||
fc->fs_private = ctx;
|
||||
fc->ops = &ovl_context_ops;
|
||||
return 0;
|
||||
|
||||
out_err:
|
||||
ovl_fs_context_free(ctx);
|
||||
return -ENOMEM;
|
||||
|
||||
}
|
||||
|
||||
static struct file_system_type ovl_fs_type = {
|
||||
.owner = THIS_MODULE,
|
||||
.name = "overlay",
|
||||
|
||||
Loading…
Reference in New Issue
Block a user