diff options
Diffstat (limited to 'ipc')
| -rw-r--r-- | ipc/Makefile | 2 | ||||
| -rw-r--r-- | ipc/ipc_sysctl.c | 93 | ||||
| -rw-r--r-- | ipc/ipcns_notifier.c | 92 | ||||
| -rw-r--r-- | ipc/msg.c | 36 | ||||
| -rw-r--r-- | ipc/namespace.c | 22 | ||||
| -rw-r--r-- | ipc/util.c | 40 |
6 files changed, 19 insertions, 266 deletions
diff --git a/ipc/Makefile b/ipc/Makefile index 9075e17..86c7300 100644 --- a/ipc/Makefile +++ b/ipc/Makefile @@ -3,7 +3,7 @@ # obj-$(CONFIG_SYSVIPC_COMPAT) += compat.o -obj-$(CONFIG_SYSVIPC) += util.o msgutil.o msg.o sem.o shm.o ipcns_notifier.o syscall.o +obj-$(CONFIG_SYSVIPC) += util.o msgutil.o msg.o sem.o shm.o syscall.o obj-$(CONFIG_SYSVIPC_SYSCTL) += ipc_sysctl.o obj_mq-$(CONFIG_COMPAT) += compat_mq.o obj-$(CONFIG_POSIX_MQUEUE) += mqueue.o msgutil.o $(obj_mq-y) diff --git a/ipc/ipc_sysctl.c b/ipc/ipc_sysctl.c index e8075b2..8ad93c2 100644 --- a/ipc/ipc_sysctl.c +++ b/ipc/ipc_sysctl.c @@ -62,29 +62,6 @@ static int proc_ipc_dointvec_minmax_orphans(struct ctl_table *table, int write, return err; } -static int proc_ipc_callback_dointvec_minmax(struct ctl_table *table, int write, - void __user *buffer, size_t *lenp, loff_t *ppos) -{ - struct ctl_table ipc_table; - size_t lenp_bef = *lenp; - int rc; - - memcpy(&ipc_table, table, sizeof(ipc_table)); - ipc_table.data = get_ipc(table); - - rc = proc_dointvec_minmax(&ipc_table, write, buffer, lenp, ppos); - - if (write && !rc && lenp_bef == *lenp) - /* - * Tunable has successfully been changed by hand. Disable its - * automatic adjustment. This simply requires unregistering - * the notifiers that trigger recalculation. - */ - unregister_ipcns_notifier(current->nsproxy->ipc_ns); - - return rc; -} - static int proc_ipc_doulongvec_minmax(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) { @@ -96,54 +73,19 @@ static int proc_ipc_doulongvec_minmax(struct ctl_table *table, int write, lenp, ppos); } -/* - * Routine that is called when the file "auto_msgmni" has successfully been - * written. - * Two values are allowed: - * 0: unregister msgmni's callback routine from the ipc namespace notifier - * chain. This means that msgmni won't be recomputed anymore upon memory - * add/remove or ipc namespace creation/removal. - * 1: register back the callback routine. - */ -static void ipc_auto_callback(int val) -{ - if (!val) - unregister_ipcns_notifier(current->nsproxy->ipc_ns); - else { - /* - * Re-enable automatic recomputing only if not already - * enabled. - */ - recompute_msgmni(current->nsproxy->ipc_ns); - cond_register_ipcns_notifier(current->nsproxy->ipc_ns); - } -} - -static int proc_ipcauto_dointvec_minmax(struct ctl_table *table, int write, +static int proc_ipc_auto_msgmni(struct ctl_table *table, int write, void __user *buffer, size_t *lenp, loff_t *ppos) { struct ctl_table ipc_table; - int oldval; - int rc; + int dummy = 0; memcpy(&ipc_table, table, sizeof(ipc_table)); - ipc_table.data = get_ipc(table); - oldval = *((int *)(ipc_table.data)); + ipc_table.data = &dummy; - rc = proc_dointvec_minmax(&ipc_table, write, buffer, lenp, ppos); + if (write) + pr_info_once("writing to auto_msgmni has no effect"); - if (write && !rc) { - int newval = *((int *)(ipc_table.data)); - /* - * The file "auto_msgmni" has correctly been set. - * React by (un)registering the corresponding tunable, if the - * value has changed. - */ - if (newval != oldval) - ipc_auto_callback(newval); - } - - return rc; + return proc_dointvec_minmax(&ipc_table, write, buffer, lenp, ppos); } #else @@ -151,8 +93,7 @@ static int proc_ipcauto_dointvec_minmax(struct ctl_table *table, int write, #define proc_ipc_dointvec NULL #define proc_ipc_dointvec_minmax NULL #define proc_ipc_dointvec_minmax_orphans NULL -#define proc_ipc_callback_dointvec_minmax NULL -#define proc_ipcauto_dointvec_minmax NULL +#define proc_ipc_auto_msgmni NULL #endif static int zero; @@ -204,11 +145,20 @@ static struct ctl_table ipc_kern_table[] = { .data = &init_ipc_ns.msg_ctlmni, .maxlen = sizeof(init_ipc_ns.msg_ctlmni), .mode = 0644, - .proc_handler = proc_ipc_callback_dointvec_minmax, + .proc_handler = proc_ipc_dointvec_minmax, .extra1 = &zero, .extra2 = &int_max, }, { + .procname = "auto_msgmni", + .data = NULL, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_ipc_auto_msgmni, + .extra1 = &zero, + .extra2 = &one, + }, + { .procname = "msgmnb", .data = &init_ipc_ns.msg_ctlmnb, .maxlen = sizeof(init_ipc_ns.msg_ctlmnb), @@ -224,15 +174,6 @@ static struct ctl_table ipc_kern_table[] = { .mode = 0644, .proc_handler = proc_ipc_dointvec, }, - { - .procname = "auto_msgmni", - .data = &init_ipc_ns.auto_msgmni, - .maxlen = sizeof(int), - .mode = 0644, - .proc_handler = proc_ipcauto_dointvec_minmax, - .extra1 = &zero, - .extra2 = &one, - }, #ifdef CONFIG_CHECKPOINT_RESTORE { .procname = "sem_next_id", diff --git a/ipc/ipcns_notifier.c b/ipc/ipcns_notifier.c deleted file mode 100644 index b9b31a4..0000000 --- a/ipc/ipcns_notifier.c +++ /dev/null @@ -1,92 +0,0 @@ -/* - * linux/ipc/ipcns_notifier.c - * Copyright (C) 2007 BULL SA. Nadia Derbey - * - * Notification mechanism for ipc namespaces: - * The callback routine registered in the memory chain invokes the ipcns - * notifier chain with the IPCNS_MEMCHANGED event. - * Each callback routine registered in the ipcns namespace recomputes msgmni - * for the owning namespace. - */ - -#include <linux/msg.h> -#include <linux/rcupdate.h> -#include <linux/notifier.h> -#include <linux/nsproxy.h> -#include <linux/ipc_namespace.h> - -#include "util.h" - - - -static BLOCKING_NOTIFIER_HEAD(ipcns_chain); - - -static int ipcns_callback(struct notifier_block *self, - unsigned long action, void *arg) -{ - struct ipc_namespace *ns; - - switch (action) { - case IPCNS_MEMCHANGED: /* amount of lowmem has changed */ - case IPCNS_CREATED: - case IPCNS_REMOVED: - /* - * It's time to recompute msgmni - */ - ns = container_of(self, struct ipc_namespace, ipcns_nb); - /* - * No need to get a reference on the ns: the 1st job of - * free_ipc_ns() is to unregister the callback routine. - * blocking_notifier_chain_unregister takes the wr lock to do - * it. - * When this callback routine is called the rd lock is held by - * blocking_notifier_call_chain. - * So the ipc ns cannot be freed while we are here. - */ - recompute_msgmni(ns); - break; - default: - break; - } - - return NOTIFY_OK; -} - -int register_ipcns_notifier(struct ipc_namespace *ns) -{ - int rc; - - memset(&ns->ipcns_nb, 0, sizeof(ns->ipcns_nb)); - ns->ipcns_nb.notifier_call = ipcns_callback; - ns->ipcns_nb.priority = IPCNS_CALLBACK_PRI; - rc = blocking_notifier_chain_register(&ipcns_chain, &ns->ipcns_nb); - if (!rc) - ns->auto_msgmni = 1; - return rc; -} - -int cond_register_ipcns_notifier(struct ipc_namespace *ns) -{ - int rc; - - memset(&ns->ipcns_nb, 0, sizeof(ns->ipcns_nb)); - ns->ipcns_nb.notifier_call = ipcns_callback; - ns->ipcns_nb.priority = IPCNS_CALLBACK_PRI; - rc = blocking_notifier_chain_cond_register(&ipcns_chain, - &ns->ipcns_nb); - if (!rc) - ns->auto_msgmni = 1; - return rc; -} - -void unregister_ipcns_notifier(struct ipc_namespace *ns) -{ - blocking_notifier_chain_unregister(&ipcns_chain, &ns->ipcns_nb); - ns->auto_msgmni = 0; -} - -int ipcns_notify(unsigned long val) -{ - return blocking_notifier_call_chain(&ipcns_chain, val, NULL); -} @@ -989,43 +989,12 @@ SYSCALL_DEFINE5(msgrcv, int, msqid, struct msgbuf __user *, msgp, size_t, msgsz, return do_msgrcv(msqid, msgp, msgsz, msgtyp, msgflg, do_msg_fill); } -/* - * Scale msgmni with the available lowmem size: the memory dedicated to msg - * queues should occupy at most 1/MSG_MEM_SCALE of lowmem. - * Also take into account the number of nsproxies created so far. - * This should be done staying within the (MSGMNI , IPCMNI/nr_ipc_ns) range. - */ -void recompute_msgmni(struct ipc_namespace *ns) -{ - struct sysinfo i; - unsigned long allowed; - int nb_ns; - - si_meminfo(&i); - allowed = (((i.totalram - i.totalhigh) / MSG_MEM_SCALE) * i.mem_unit) - / MSGMNB; - nb_ns = atomic_read(&nr_ipc_ns); - allowed /= nb_ns; - - if (allowed < MSGMNI) { - ns->msg_ctlmni = MSGMNI; - return; - } - - if (allowed > IPCMNI / nb_ns) { - ns->msg_ctlmni = IPCMNI / nb_ns; - return; - } - - ns->msg_ctlmni = allowed; -} void msg_init_ns(struct ipc_namespace *ns) { ns->msg_ctlmax = MSGMAX; ns->msg_ctlmnb = MSGMNB; - - recompute_msgmni(ns); + ns->msg_ctlmni = MSGMNI; atomic_set(&ns->msg_bytes, 0); atomic_set(&ns->msg_hdrs, 0); @@ -1069,9 +1038,6 @@ void __init msg_init(void) { msg_init_ns(&init_ipc_ns); - printk(KERN_INFO "msgmni has been set to %d\n", - init_ipc_ns.msg_ctlmni); - ipc_init_proc_interface("sysvipc/msg", " key msqid perms cbytes qnum lspid lrpid uid gid cuid cgid stime rtime ctime\n", IPC_MSG_IDS, sysvipc_msg_proc_show); diff --git a/ipc/namespace.c b/ipc/namespace.c index b54468e..1a3ffd4 100644 --- a/ipc/namespace.c +++ b/ipc/namespace.c @@ -45,14 +45,6 @@ static struct ipc_namespace *create_ipc_ns(struct user_namespace *user_ns, msg_init_ns(ns); shm_init_ns(ns); - /* - * msgmni has already been computed for the new ipc ns. - * Thus, do the ipcns creation notification before registering that - * new ipcns in the chain. - */ - ipcns_notify(IPCNS_CREATED); - register_ipcns_notifier(ns); - ns->user_ns = get_user_ns(user_ns); return ns; @@ -99,25 +91,11 @@ void free_ipcs(struct ipc_namespace *ns, struct ipc_ids *ids, static void free_ipc_ns(struct ipc_namespace *ns) { - /* - * Unregistering the hotplug notifier at the beginning guarantees - * that the ipc namespace won't be freed while we are inside the - * callback routine. Since the blocking_notifier_chain_XXX routines - * hold a rw lock on the notifier list, unregister_ipcns_notifier() - * won't take the rw lock before blocking_notifier_call_chain() has - * released the rd lock. - */ - unregister_ipcns_notifier(ns); sem_exit_ns(ns); msg_exit_ns(ns); shm_exit_ns(ns); atomic_dec(&nr_ipc_ns); - /* - * Do the ipcns removal notification after decrementing nr_ipc_ns in - * order to have a correct value when recomputing msgmni. - */ - ipcns_notify(IPCNS_REMOVED); put_user_ns(ns->user_ns); proc_free_inum(ns->proc_inum); kfree(ns); @@ -71,44 +71,6 @@ struct ipc_proc_iface { int (*show)(struct seq_file *, void *); }; -static void ipc_memory_notifier(struct work_struct *work) -{ - ipcns_notify(IPCNS_MEMCHANGED); -} - -static int ipc_memory_callback(struct notifier_block *self, - unsigned long action, void *arg) -{ - static DECLARE_WORK(ipc_memory_wq, ipc_memory_notifier); - - switch (action) { - case MEM_ONLINE: /* memory successfully brought online */ - case MEM_OFFLINE: /* or offline: it's time to recompute msgmni */ - /* - * This is done by invoking the ipcns notifier chain with the - * IPC_MEMCHANGED event. - * In order not to keep the lock on the hotplug memory chain - * for too long, queue a work item that will, when waken up, - * activate the ipcns notification chain. - */ - schedule_work(&ipc_memory_wq); - break; - case MEM_GOING_ONLINE: - case MEM_GOING_OFFLINE: - case MEM_CANCEL_ONLINE: - case MEM_CANCEL_OFFLINE: - default: - break; - } - - return NOTIFY_OK; -} - -static struct notifier_block ipc_memory_nb = { - .notifier_call = ipc_memory_callback, - .priority = IPC_CALLBACK_PRI, -}; - /** * ipc_init - initialise ipc subsystem * @@ -124,8 +86,6 @@ static int __init ipc_init(void) sem_init(); msg_init(); shm_init(); - register_hotmemory_notifier(&ipc_memory_nb); - register_ipcns_notifier(&init_ipc_ns); return 0; } device_initcall(ipc_init); |
