diff options
| -rw-r--r-- | drivers/firmware/efi/efi.c | 6 | ||||
| -rw-r--r-- | drivers/firmware/efi/vars.c | 8 | ||||
| -rw-r--r-- | fs/efivarfs/internal.h | 2 | ||||
| -rw-r--r-- | fs/efivarfs/super.c | 27 | ||||
| -rw-r--r-- | include/linux/efi.h | 8 |
5 files changed, 51 insertions, 0 deletions
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 32a67c61c3b8..4fcda50acfa4 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -32,6 +32,7 @@ #include <linux/ucs2_string.h> #include <linux/memblock.h> #include <linux/security.h> +#include <linux/notifier.h> #include <asm/early_ioremap.h> @@ -187,6 +188,9 @@ static const struct attribute_group efi_subsys_attr_group = { .is_visible = efi_attr_is_visible, }; +struct blocking_notifier_head efivar_ops_nh; +EXPORT_SYMBOL_GPL(efivar_ops_nh); + static struct efivars generic_efivars; static struct efivar_operations generic_ops; @@ -431,6 +435,8 @@ static int __init efisubsys_init(void) platform_device_register_simple("efivars", 0, NULL, 0); } + BLOCKING_INIT_NOTIFIER_HEAD(&efivar_ops_nh); + error = sysfs_create_group(efi_kobj, &efi_subsys_attr_group); if (error) { pr_err("efi: Sysfs attribute export failed with error %d.\n", diff --git a/drivers/firmware/efi/vars.c b/drivers/firmware/efi/vars.c index e9dc7116daf1..f654e6f6af87 100644 --- a/drivers/firmware/efi/vars.c +++ b/drivers/firmware/efi/vars.c @@ -63,6 +63,7 @@ int efivars_register(struct efivars *efivars, const struct efivar_operations *ops) { int rv; + int event; if (down_interruptible(&efivars_lock)) return -EINTR; @@ -77,6 +78,13 @@ int efivars_register(struct efivars *efivars, __efivars = efivars; + if (efivar_supports_writes()) + event = EFIVAR_OPS_RDWR; + else + event = EFIVAR_OPS_RDONLY; + + blocking_notifier_call_chain(&efivar_ops_nh, event, NULL); + pr_info("Registered efivars operations\n"); rv = 0; out: diff --git a/fs/efivarfs/internal.h b/fs/efivarfs/internal.h index 1dc0ccce3cc3..169252e6dc46 100644 --- a/fs/efivarfs/internal.h +++ b/fs/efivarfs/internal.h @@ -17,6 +17,8 @@ struct efivarfs_mount_opts { struct efivarfs_fs_info { struct efivarfs_mount_opts mount_opts; struct list_head efivarfs_list; + struct super_block *sb; + struct notifier_block nb; }; struct efi_variable { diff --git a/fs/efivarfs/super.c b/fs/efivarfs/super.c index cee325b5bbdd..6038dd39367a 100644 --- a/fs/efivarfs/super.c +++ b/fs/efivarfs/super.c @@ -15,10 +15,30 @@ #include <linux/slab.h> #include <linux/magic.h> #include <linux/statfs.h> +#include <linux/notifier.h> #include <linux/printk.h> #include "internal.h" +static int efivarfs_ops_notifier(struct notifier_block *nb, unsigned long event, + void *data) +{ + struct efivarfs_fs_info *sfi = container_of(nb, struct efivarfs_fs_info, nb); + + switch (event) { + case EFIVAR_OPS_RDONLY: + sfi->sb->s_flags |= SB_RDONLY; + break; + case EFIVAR_OPS_RDWR: + sfi->sb->s_flags &= ~SB_RDONLY; + break; + default: + return NOTIFY_DONE; + } + + return NOTIFY_OK; +} + static void efivarfs_evict_inode(struct inode *inode) { clear_inode(inode); @@ -317,6 +337,12 @@ static int efivarfs_fill_super(struct super_block *sb, struct fs_context *fc) if (!root) return -ENOMEM; + sfi->sb = sb; + sfi->nb.notifier_call = efivarfs_ops_notifier; + err = blocking_notifier_chain_register(&efivar_ops_nh, &sfi->nb); + if (err) + return err; + err = efivar_init(efivarfs_callback, (void *)sb, true, &sfi->efivarfs_list); if (err) @@ -371,6 +397,7 @@ static void efivarfs_kill_sb(struct super_block *sb) { struct efivarfs_fs_info *sfi = sb->s_fs_info; + blocking_notifier_chain_unregister(&efivar_ops_nh, &sfi->nb); kill_litter_super(sb); /* Remove all entries and destroy */ diff --git a/include/linux/efi.h b/include/linux/efi.h index 3668aa204c47..c74f47711f0b 100644 --- a/include/linux/efi.h +++ b/include/linux/efi.h @@ -1349,6 +1349,14 @@ bool efi_config_table_is_usable(const efi_guid_t *guid, unsigned long table) umode_t efi_attr_is_visible(struct kobject *kobj, struct attribute *attr, int n); +/* + * efivar ops event type + */ +#define EFIVAR_OPS_RDONLY 0 +#define EFIVAR_OPS_RDWR 1 + +extern struct blocking_notifier_head efivar_ops_nh; + void efivars_generic_ops_register(void); void efivars_generic_ops_unregister(void); |