X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=kernel%2Fuser.c;h=bc1c48d35cb32726623b37b47a09d4325aaf4074;hb=acf63867ae06ef95eea7bf445ded2f05528a81b1;hp=e91331c457e270e8ca7aaa7f91a2f45ecde2dcc8;hpb=e6d5a11dad44b8ae18ca8fc4ecb72ccccfa0a2d2;p=firefly-linux-kernel-4.4.55.git diff --git a/kernel/user.c b/kernel/user.c index e91331c457e2..bc1c48d35cb3 100644 --- a/kernel/user.c +++ b/kernel/user.c @@ -115,7 +115,7 @@ static void sched_switch_user(struct task_struct *p) { } #if defined(CONFIG_FAIR_USER_SCHED) && defined(CONFIG_SYSFS) -static struct kobject uids_kobject; /* represents /sys/kernel/uids directory */ +static struct kset *uids_kset; /* represents the /sys/kernel/uids/ directory */ static DEFINE_MUTEX(uids_mutex); static inline void uids_mutex_lock(void) @@ -128,85 +128,83 @@ static inline void uids_mutex_unlock(void) mutex_unlock(&uids_mutex); } -/* return cpu shares held by the user */ -ssize_t cpu_shares_show(struct kset *kset, char *buffer) +/* uid directory attributes */ +static ssize_t cpu_shares_show(struct kobject *kobj, + struct kobj_attribute *attr, + char *buf) { - struct user_struct *up = container_of(kset, struct user_struct, kset); + struct user_struct *up = container_of(kobj, struct user_struct, kobj); - return sprintf(buffer, "%lu\n", sched_group_shares(up->tg)); + return sprintf(buf, "%lu\n", sched_group_shares(up->tg)); } -/* modify cpu shares held by the user */ -ssize_t cpu_shares_store(struct kset *kset, const char *buffer, size_t size) +static ssize_t cpu_shares_store(struct kobject *kobj, + struct kobj_attribute *attr, + const char *buf, size_t size) { - struct user_struct *up = container_of(kset, struct user_struct, kset); + struct user_struct *up = container_of(kobj, struct user_struct, kobj); unsigned long shares; int rc; - sscanf(buffer, "%lu", &shares); + sscanf(buf, "%lu", &shares); rc = sched_group_set_shares(up->tg, shares); return (rc ? rc : size); } -static void user_attr_init(struct subsys_attribute *sa, char *name, int mode) +static struct kobj_attribute cpu_share_attr = + __ATTR(cpu_share, 0644, cpu_shares_show, cpu_shares_store); + +/* default attributes per uid directory */ +static struct attribute *uids_attributes[] = { + &cpu_share_attr.attr, + NULL +}; + +/* the lifetime of user_struct is not managed by the core (now) */ +static void uids_release(struct kobject *kobj) { - sa->attr.name = name; - sa->attr.mode = mode; - sa->show = cpu_shares_show; - sa->store = cpu_shares_store; + return; } -/* Create "/sys/kernel/uids/" directory and - * "/sys/kernel/uids//cpu_share" file for this user. - */ -static int user_kobject_create(struct user_struct *up) +static struct kobj_type uids_ktype = { + .sysfs_ops = &kobj_sysfs_ops, + .default_attrs = uids_attributes, + .release = uids_release, +}; + +/* create /sys/kernel/uids//cpu_share file for this user */ +static int uids_user_create(struct user_struct *up) { - struct kset *kset = &up->kset; - struct kobject *kobj = &kset->kobj; + struct kobject *kobj = &up->kobj; int error; - memset(kset, 0, sizeof(struct kset)); - kobj->parent = &uids_kobject; /* create under /sys/kernel/uids dir */ - kobject_set_name(kobj, "%d", up->uid); - kset_init(kset); - user_attr_init(&up->user_attr, "cpu_share", 0644); - - error = kobject_add(kobj); - if (error) + memset(kobj, 0, sizeof(struct kobject)); + kobj->kset = uids_kset; + error = kobject_init_and_add(kobj, &uids_ktype, NULL, "%d", up->uid); + if (error) { + kobject_put(kobj); goto done; - - error = sysfs_create_file(kobj, &up->user_attr.attr); - if (error) - kobject_del(kobj); + } kobject_uevent(kobj, KOBJ_ADD); - done: return error; } -/* create these in sysfs filesystem: +/* create these entries in sysfs: * "/sys/kernel/uids" directory * "/sys/kernel/uids/0" directory (for root user) * "/sys/kernel/uids/0/cpu_share" file (for root user) */ -int __init uids_kobject_init(void) +int __init uids_sysfs_init(void) { - int error; - - /* create under /sys/kernel dir */ - uids_kobject.parent = &kernel_subsys.kobj; - uids_kobject.kset = &kernel_subsys; - kobject_set_name(&uids_kobject, "uids"); - kobject_init(&uids_kobject); + uids_kset = kset_create_and_add("uids", NULL, kernel_kobj); + if (!uids_kset) + return -ENOMEM; - error = kobject_add(&uids_kobject); - if (!error) - error = user_kobject_create(&root_user); - - return error; + return uids_user_create(&root_user); } /* work function to remove sysfs directory for a user and free up @@ -215,7 +213,6 @@ int __init uids_kobject_init(void) static void remove_user_sysfs_dir(struct work_struct *w) { struct user_struct *up = container_of(w, struct user_struct, work); - struct kobject *kobj = &up->kset.kobj; unsigned long flags; int remove_user = 0; @@ -237,9 +234,9 @@ static void remove_user_sysfs_dir(struct work_struct *w) if (!remove_user) goto done; - sysfs_remove_file(kobj, &up->user_attr.attr); - kobject_uevent(kobj, KOBJ_REMOVE); - kobject_del(kobj); + kobject_uevent(&up->kobj, KOBJ_REMOVE); + kobject_del(&up->kobj); + kobject_put(&up->kobj); sched_destroy_user(up); key_put(up->uid_keyring); @@ -266,7 +263,8 @@ static inline void free_user(struct user_struct *up, unsigned long flags) #else /* CONFIG_FAIR_USER_SCHED && CONFIG_SYSFS */ -static inline int user_kobject_create(struct user_struct *up) { return 0; } +int uids_sysfs_init(void) { return 0; } +static inline int uids_user_create(struct user_struct *up) { return 0; } static inline void uids_mutex_lock(void) { } static inline void uids_mutex_unlock(void) { } @@ -321,9 +319,9 @@ void free_uid(struct user_struct *up) struct user_struct * alloc_uid(struct user_namespace *ns, uid_t uid) { struct hlist_head *hashent = uidhashentry(ns, uid); - struct user_struct *up; + struct user_struct *up, *new; - /* Make uid_hash_find() + user_kobject_create() + uid_hash_insert() + /* Make uid_hash_find() + uids_user_create() + uid_hash_insert() * atomic. */ uids_mutex_lock(); @@ -333,11 +331,10 @@ struct user_struct * alloc_uid(struct user_namespace *ns, uid_t uid) spin_unlock_irq(&uidhash_lock); if (!up) { - struct user_struct *new; - new = kmem_cache_alloc(uid_cachep, GFP_KERNEL); if (!new) - return NULL; + goto out_unlock; + new->uid = uid; atomic_set(&new->__count, 1); atomic_set(&new->processes, 0); @@ -352,26 +349,14 @@ struct user_struct * alloc_uid(struct user_namespace *ns, uid_t uid) #endif new->locked_shm = 0; - if (alloc_uid_keyring(new, current) < 0) { - kmem_cache_free(uid_cachep, new); - return NULL; - } + if (alloc_uid_keyring(new, current) < 0) + goto out_free_user; - if (sched_create_user(new) < 0) { - key_put(new->uid_keyring); - key_put(new->session_keyring); - kmem_cache_free(uid_cachep, new); - return NULL; - } + if (sched_create_user(new) < 0) + goto out_put_keys; - if (user_kobject_create(new)) { - sched_destroy_user(new); - key_put(new->uid_keyring); - key_put(new->session_keyring); - kmem_cache_free(uid_cachep, new); - uids_mutex_unlock(); - return NULL; - } + if (uids_user_create(new)) + goto out_destoy_sched; /* * Before adding this, check whether we raced @@ -399,6 +384,17 @@ struct user_struct * alloc_uid(struct user_namespace *ns, uid_t uid) uids_mutex_unlock(); return up; + +out_destoy_sched: + sched_destroy_user(new); +out_put_keys: + key_put(new->uid_keyring); + key_put(new->session_keyring); +out_free_user: + kmem_cache_free(uid_cachep, new); +out_unlock: + uids_mutex_unlock(); + return NULL; } void switch_uid(struct user_struct *new_user)