ipc: store ipcs into IDRs
This patch introduces ipcs storage into IDRs. The main changes are:
. This ipc_ids structure is changed: the entries array is changed into a
root idr structure.
. The grow_ary() routine is removed: it is not needed anymore when adding
an ipc structure, since we are now using the IDR facility.
. The ipc_rmid() routine interface is changed:
. there is no need for this routine to return the pointer passed in as
argument: it is now declared as a void
. since the id is now part of the kern_ipc_perm structure, no need to
have it as an argument to the routine
Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/ipc.h b/include/linux/ipc.h
index ee11183..96988d1 100644
--- a/include/linux/ipc.h
+++ b/include/linux/ipc.h
@@ -89,6 +89,7 @@
{
spinlock_t lock;
int deleted;
+ int id;
key_t key;
uid_t uid;
gid_t gid;
diff --git a/include/linux/msg.h b/include/linux/msg.h
index f1b60740d..10a3d5a 100644
--- a/include/linux/msg.h
+++ b/include/linux/msg.h
@@ -77,7 +77,6 @@
/* one msq_queue structure for each present queue on the system */
struct msg_queue {
struct kern_ipc_perm q_perm;
- int q_id;
time_t q_stime; /* last msgsnd time */
time_t q_rtime; /* last msgrcv time */
time_t q_ctime; /* last change time */
diff --git a/include/linux/sem.h b/include/linux/sem.h
index 9aaffb0..c8eaad9 100644
--- a/include/linux/sem.h
+++ b/include/linux/sem.h
@@ -90,7 +90,6 @@
/* One sem_array data structure for each set of semaphores in the system. */
struct sem_array {
struct kern_ipc_perm sem_perm; /* permissions .. see ipc.h */
- int sem_id;
time_t sem_otime; /* last semop time */
time_t sem_ctime; /* last change time */
struct sem *sem_base; /* ptr to first semaphore in array */
diff --git a/include/linux/shm.h b/include/linux/shm.h
index bea65d9..eeaed92 100644
--- a/include/linux/shm.h
+++ b/include/linux/shm.h
@@ -79,7 +79,6 @@
{
struct kern_ipc_perm shm_perm;
struct file * shm_file;
- int id;
unsigned long shm_nattch;
unsigned long shm_segsz;
time_t shm_atim;
diff --git a/ipc/msg.c b/ipc/msg.c
index 3194686..08591a0 100644
--- a/ipc/msg.c
+++ b/ipc/msg.c
@@ -75,13 +75,12 @@
#define msg_lock(ns, id) ((struct msg_queue*)ipc_lock(&msg_ids(ns), id))
#define msg_unlock(msq) ipc_unlock(&(msq)->q_perm)
-#define msg_rmid(ns, id) ((struct msg_queue*)ipc_rmid(&msg_ids(ns), id))
#define msg_checkid(ns, msq, msgid) \
ipc_checkid(&msg_ids(ns), &msq->q_perm, msgid)
#define msg_buildid(ns, id, seq) \
ipc_buildid(&msg_ids(ns), id, seq)
-static void freeque (struct ipc_namespace *ns, struct msg_queue *msq, int id);
+static void freeque(struct ipc_namespace *, struct msg_queue *);
static int newque (struct ipc_namespace *ns, key_t key, int msgflg);
#ifdef CONFIG_PROC_FS
static int sysvipc_msg_proc_show(struct seq_file *s, void *it);
@@ -93,7 +92,7 @@
ns->msg_ctlmax = MSGMAX;
ns->msg_ctlmnb = MSGMNB;
ns->msg_ctlmni = MSGMNI;
- ipc_init_ids(ids, ns->msg_ctlmni);
+ ipc_init_ids(ids);
}
int msg_init_ns(struct ipc_namespace *ns)
@@ -110,20 +109,24 @@
void msg_exit_ns(struct ipc_namespace *ns)
{
- int i;
struct msg_queue *msq;
+ int next_id;
+ int total, in_use;
mutex_lock(&msg_ids(ns).mutex);
- for (i = 0; i <= msg_ids(ns).max_id; i++) {
- msq = msg_lock(ns, i);
+
+ in_use = msg_ids(ns).in_use;
+
+ for (total = 0, next_id = 0; total < in_use; next_id++) {
+ msq = idr_find(&msg_ids(ns).ipcs_idr, next_id);
if (msq == NULL)
continue;
-
- freeque(ns, msq, i);
+ ipc_lock_by_ptr(&msq->q_perm);
+ freeque(ns, msq);
+ total++;
}
mutex_unlock(&msg_ids(ns).mutex);
- ipc_fini_ids(ns->ids[IPC_MSG_IDS]);
kfree(ns->ids[IPC_MSG_IDS]);
ns->ids[IPC_MSG_IDS] = NULL;
}
@@ -136,6 +139,11 @@
IPC_MSG_IDS, sysvipc_msg_proc_show);
}
+static inline void msg_rmid(struct ipc_namespace *ns, struct msg_queue *s)
+{
+ ipc_rmid(&msg_ids(ns), &s->q_perm);
+}
+
static int newque (struct ipc_namespace *ns, key_t key, int msgflg)
{
struct msg_queue *msq;
@@ -155,6 +163,9 @@
return retval;
}
+ /*
+ * ipc_addid() locks msq
+ */
id = ipc_addid(&msg_ids(ns), &msq->q_perm, ns->msg_ctlmni);
if (id == -1) {
security_msg_queue_free(msq);
@@ -162,7 +173,7 @@
return -ENOSPC;
}
- msq->q_id = msg_buildid(ns, id, msq->q_perm.seq);
+ msq->q_perm.id = msg_buildid(ns, id, msq->q_perm.seq);
msq->q_stime = msq->q_rtime = 0;
msq->q_ctime = get_seconds();
msq->q_cbytes = msq->q_qnum = 0;
@@ -171,9 +182,10 @@
INIT_LIST_HEAD(&msq->q_messages);
INIT_LIST_HEAD(&msq->q_receivers);
INIT_LIST_HEAD(&msq->q_senders);
+
msg_unlock(msq);
- return msq->q_id;
+ return msq->q_perm.id;
}
static inline void ss_add(struct msg_queue *msq, struct msg_sender *mss)
@@ -225,18 +237,18 @@
/*
* freeque() wakes up waiters on the sender and receiver waiting queue,
* removes the message queue from message queue ID
- * array, and cleans up all the messages associated with this queue.
+ * IDR, and cleans up all the messages associated with this queue.
*
- * msg_ids.mutex and the spinlock for this message queue is hold
+ * msg_ids.mutex and the spinlock for this message queue are held
* before freeque() is called. msg_ids.mutex remains locked on exit.
*/
-static void freeque(struct ipc_namespace *ns, struct msg_queue *msq, int id)
+static void freeque(struct ipc_namespace *ns, struct msg_queue *msq)
{
struct list_head *tmp;
expunge_all(msq, -EIDRM);
ss_wakeup(&msq->q_senders, 1);
- msq = msg_rmid(ns, id);
+ msg_rmid(ns, msq);
msg_unlock(msq);
tmp = msq->q_messages.next;
@@ -255,36 +267,51 @@
asmlinkage long sys_msgget(key_t key, int msgflg)
{
struct msg_queue *msq;
- int id, ret = -EPERM;
+ int ret;
struct ipc_namespace *ns;
ns = current->nsproxy->ipc_ns;
-
- mutex_lock(&msg_ids(ns).mutex);
- if (key == IPC_PRIVATE)
- ret = newque(ns, key, msgflg);
- else if ((id = ipc_findkey(&msg_ids(ns), key)) == -1) { /* key not used */
- if (!(msgflg & IPC_CREAT))
- ret = -ENOENT;
- else
- ret = newque(ns, key, msgflg);
- } else if (msgflg & IPC_CREAT && msgflg & IPC_EXCL) {
- ret = -EEXIST;
- } else {
- msq = msg_lock(ns, id);
- BUG_ON(msq == NULL);
- if (ipcperms(&msq->q_perm, msgflg))
- ret = -EACCES;
- else {
- int qid = msg_buildid(ns, id, msq->q_perm.seq);
- ret = security_msg_queue_associate(msq, msgflg);
- if (!ret)
- ret = qid;
+ ret = idr_pre_get(&msg_ids(ns).ipcs_idr, GFP_KERNEL);
+
+ if (key == IPC_PRIVATE) {
+ if (!ret)
+ ret = -ENOMEM;
+ else {
+ mutex_lock(&msg_ids(ns).mutex);
+ ret = newque(ns, key, msgflg);
+ mutex_unlock(&msg_ids(ns).mutex);
}
- msg_unlock(msq);
+ } else {
+ mutex_lock(&msg_ids(ns).mutex);
+ msq = (struct msg_queue *) ipc_findkey(&msg_ids(ns), key);
+ if (msq == NULL) {
+ /* key not used */
+ if (!(msgflg & IPC_CREAT))
+ ret = -ENOENT;
+ else if (!ret)
+ ret = -ENOMEM;
+ else
+ ret = newque(ns, key, msgflg);
+ } else {
+ /* msq has been locked by ipc_findkey() */
+
+ if (msgflg & IPC_CREAT && msgflg & IPC_EXCL)
+ ret = -EEXIST;
+ else {
+ if (ipcperms(&msq->q_perm, msgflg))
+ ret = -EACCES;
+ else {
+ ret = security_msg_queue_associate(
+ msq, msgflg);
+ if (!ret)
+ ret = msq->q_perm.id;
+ }
+ }
+ msg_unlock(msq);
+ }
+ mutex_unlock(&msg_ids(ns).mutex);
}
- mutex_unlock(&msg_ids(ns).mutex);
return ret;
}
@@ -430,13 +457,13 @@
msginfo.msgpool = MSGPOOL;
msginfo.msgtql = MSGTQL;
}
- max_id = msg_ids(ns).max_id;
+ max_id = ipc_get_maxid(&msg_ids(ns));
mutex_unlock(&msg_ids(ns).mutex);
if (copy_to_user(buf, &msginfo, sizeof(struct msginfo)))
return -EFAULT;
return (max_id < 0) ? 0 : max_id;
}
- case MSG_STAT:
+ case MSG_STAT: /* msqid is an index rather than a msg queue id */
case IPC_STAT:
{
struct msqid64_ds tbuf;
@@ -444,8 +471,6 @@
if (!buf)
return -EFAULT;
- if (cmd == MSG_STAT && msqid >= msg_ids(ns).entries->size)
- return -EINVAL;
memset(&tbuf, 0, sizeof(tbuf));
@@ -454,7 +479,7 @@
return -EINVAL;
if (cmd == MSG_STAT) {
- success_return = msg_buildid(ns, msqid, msq->q_perm.seq);
+ success_return = msq->q_perm.id;
} else {
err = -EIDRM;
if (msg_checkid(ns, msq, msqid))
@@ -552,7 +577,7 @@
break;
}
case IPC_RMID:
- freeque(ns, msq, msqid);
+ freeque(ns, msq);
break;
}
err = 0;
@@ -926,7 +951,7 @@
return seq_printf(s,
"%10d %10d %4o %10lu %10lu %5u %5u %5u %5u %5u %5u %10lu %10lu %10lu\n",
msq->q_perm.key,
- msq->q_id,
+ msq->q_perm.id,
msq->q_perm.mode,
msq->q_cbytes,
msq->q_qnum,
diff --git a/ipc/sem.c b/ipc/sem.c
index 64ff426..f92a256 100644
--- a/ipc/sem.c
+++ b/ipc/sem.c
@@ -90,7 +90,6 @@
#define sem_lock(ns, id) ((struct sem_array*)ipc_lock(&sem_ids(ns), id))
#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm)
-#define sem_rmid(ns, id) ((struct sem_array*)ipc_rmid(&sem_ids(ns), id))
#define sem_checkid(ns, sma, semid) \
ipc_checkid(&sem_ids(ns),&sma->sem_perm,semid)
#define sem_buildid(ns, id, seq) \
@@ -99,7 +98,7 @@
static struct ipc_ids init_sem_ids;
static int newary(struct ipc_namespace *, key_t, int, int);
-static void freeary(struct ipc_namespace *ns, struct sem_array *sma, int id);
+static void freeary(struct ipc_namespace *, struct sem_array *);
#ifdef CONFIG_PROC_FS
static int sysvipc_sem_proc_show(struct seq_file *s, void *it);
#endif
@@ -129,7 +128,7 @@
ns->sc_semopm = SEMOPM;
ns->sc_semmni = SEMMNI;
ns->used_sems = 0;
- ipc_init_ids(ids, ns->sc_semmni);
+ ipc_init_ids(ids);
}
int sem_init_ns(struct ipc_namespace *ns)
@@ -146,20 +145,24 @@
void sem_exit_ns(struct ipc_namespace *ns)
{
- int i;
struct sem_array *sma;
+ int next_id;
+ int total, in_use;
mutex_lock(&sem_ids(ns).mutex);
- for (i = 0; i <= sem_ids(ns).max_id; i++) {
- sma = sem_lock(ns, i);
+
+ in_use = sem_ids(ns).in_use;
+
+ for (total = 0, next_id = 0; total < in_use; next_id++) {
+ sma = idr_find(&sem_ids(ns).ipcs_idr, next_id);
if (sma == NULL)
continue;
-
- freeary(ns, sma, i);
+ ipc_lock_by_ptr(&sma->sem_perm);
+ freeary(ns, sma);
+ total++;
}
mutex_unlock(&sem_ids(ns).mutex);
- ipc_fini_ids(ns->ids[IPC_SEM_IDS]);
kfree(ns->ids[IPC_SEM_IDS]);
ns->ids[IPC_SEM_IDS] = NULL;
}
@@ -172,6 +175,11 @@
IPC_SEM_IDS, sysvipc_sem_proc_show);
}
+static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s)
+{
+ ipc_rmid(&sem_ids(ns), &s->sem_perm);
+}
+
/*
* Lockless wakeup algorithm:
* Without the check/retry algorithm a lockless wakeup is possible:
@@ -243,7 +251,7 @@
}
ns->used_sems += nsems;
- sma->sem_id = sem_buildid(ns, id, sma->sem_perm.seq);
+ sma->sem_perm.id = sem_buildid(ns, id, sma->sem_perm.seq);
sma->sem_base = (struct sem *) &sma[1];
/* sma->sem_pending = NULL; */
sma->sem_pending_last = &sma->sem_pending;
@@ -252,12 +260,12 @@
sma->sem_ctime = get_seconds();
sem_unlock(sma);
- return sma->sem_id;
+ return sma->sem_perm.id;
}
asmlinkage long sys_semget (key_t key, int nsems, int semflg)
{
- int id, err = -EINVAL;
+ int err;
struct sem_array *sma;
struct ipc_namespace *ns;
@@ -265,34 +273,50 @@
if (nsems < 0 || nsems > ns->sc_semmsl)
return -EINVAL;
- mutex_lock(&sem_ids(ns).mutex);
-
+
+ err = idr_pre_get(&sem_ids(ns).ipcs_idr, GFP_KERNEL);
+
if (key == IPC_PRIVATE) {
- err = newary(ns, key, nsems, semflg);
- } else if ((id = ipc_findkey(&sem_ids(ns), key)) == -1) { /* key not used */
- if (!(semflg & IPC_CREAT))
- err = -ENOENT;
- else
- err = newary(ns, key, nsems, semflg);
- } else if (semflg & IPC_CREAT && semflg & IPC_EXCL) {
- err = -EEXIST;
- } else {
- sma = sem_lock(ns, id);
- BUG_ON(sma==NULL);
- if (nsems > sma->sem_nsems)
- err = -EINVAL;
- else if (ipcperms(&sma->sem_perm, semflg))
- err = -EACCES;
+ if (!err)
+ err = -ENOMEM;
else {
- int semid = sem_buildid(ns, id, sma->sem_perm.seq);
- err = security_sem_associate(sma, semflg);
- if (!err)
- err = semid;
+ mutex_lock(&sem_ids(ns).mutex);
+ err = newary(ns, key, nsems, semflg);
+ mutex_unlock(&sem_ids(ns).mutex);
}
- sem_unlock(sma);
+ } else {
+ mutex_lock(&sem_ids(ns).mutex);
+ sma = (struct sem_array *) ipc_findkey(&sem_ids(ns), key);
+ if (sma == NULL) {
+ /* key not used */
+ if (!(semflg & IPC_CREAT))
+ err = -ENOENT;
+ else if (!err)
+ err = -ENOMEM;
+ else
+ err = newary(ns, key, nsems, semflg);
+ } else {
+ /* sma has been locked by ipc_findkey() */
+
+ if (semflg & IPC_CREAT && semflg & IPC_EXCL)
+ err = -EEXIST;
+ else {
+ if (nsems > sma->sem_nsems)
+ err = -EINVAL;
+ else if (ipcperms(&sma->sem_perm, semflg))
+ err = -EACCES;
+ else {
+ err = security_sem_associate(sma,
+ semflg);
+ if (!err)
+ err = sma->sem_perm.id;
+ }
+ }
+ sem_unlock(sma);
+ }
+ mutex_unlock(&sem_ids(ns).mutex);
}
- mutex_unlock(&sem_ids(ns).mutex);
return err;
}
@@ -491,11 +515,10 @@
* the spinlock for this semaphore set hold. sem_ids.mutex remains locked
* on exit.
*/
-static void freeary (struct ipc_namespace *ns, struct sem_array *sma, int id)
+static void freeary(struct ipc_namespace *ns, struct sem_array *sma)
{
struct sem_undo *un;
struct sem_queue *q;
- int size;
/* Invalidate the existing undo structures for this semaphore set.
* (They will be freed without any further action in exit_sem()
@@ -518,12 +541,11 @@
q = n;
}
- /* Remove the semaphore set from the ID array*/
- sma = sem_rmid(ns, id);
+ /* Remove the semaphore set from the IDR */
+ sem_rmid(ns, sma);
sem_unlock(sma);
ns->used_sems -= sma->sem_nsems;
- size = sizeof (*sma) + sma->sem_nsems * sizeof (struct sem);
security_sem_free(sma);
ipc_rcu_putref(sma);
}
@@ -584,7 +606,7 @@
seminfo.semusz = SEMUSZ;
seminfo.semaem = SEMAEM;
}
- max_id = sem_ids(ns).max_id;
+ max_id = ipc_get_maxid(&sem_ids(ns));
mutex_unlock(&sem_ids(ns).mutex);
if (copy_to_user (arg.__buf, &seminfo, sizeof(struct seminfo)))
return -EFAULT;
@@ -595,9 +617,6 @@
struct semid64_ds tbuf;
int id;
- if(semid >= sem_ids(ns).entries->size)
- return -EINVAL;
-
memset(&tbuf,0,sizeof(tbuf));
sma = sem_lock(ns, semid);
@@ -612,7 +631,7 @@
if (err)
goto out_unlock;
- id = sem_buildid(ns, semid, sma->sem_perm.seq);
+ id = sma->sem_perm.id;
kernel_to_ipc64_perm(&sma->sem_perm, &tbuf.sem_perm);
tbuf.sem_otime = sma->sem_otime;
@@ -894,7 +913,7 @@
switch(cmd){
case IPC_RMID:
- freeary(ns, sma, semid);
+ freeary(ns, sma);
err = 0;
break;
case IPC_SET:
@@ -1402,7 +1421,7 @@
return seq_printf(s,
"%10d %10d %4o %10lu %5u %5u %5u %5u %10lu %10lu\n",
sma->sem_perm.key,
- sma->sem_id,
+ sma->sem_perm.id,
sma->sem_perm.mode,
sma->sem_nsems,
sma->sem_perm.uid,
diff --git a/ipc/shm.c b/ipc/shm.c
index b9d2729..dcc3332 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -84,7 +84,7 @@
ns->shm_ctlall = SHMALL;
ns->shm_ctlmni = SHMMNI;
ns->shm_tot = 0;
- ipc_init_ids(ids, 1);
+ ipc_init_ids(ids);
}
static void do_shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *shp)
@@ -112,20 +112,24 @@
void shm_exit_ns(struct ipc_namespace *ns)
{
- int i;
struct shmid_kernel *shp;
+ int next_id;
+ int total, in_use;
mutex_lock(&shm_ids(ns).mutex);
- for (i = 0; i <= shm_ids(ns).max_id; i++) {
- shp = shm_lock(ns, i);
+
+ in_use = shm_ids(ns).in_use;
+
+ for (total = 0, next_id = 0; total < in_use; next_id++) {
+ shp = idr_find(&shm_ids(ns).ipcs_idr, next_id);
if (shp == NULL)
continue;
-
+ ipc_lock_by_ptr(&shp->shm_perm);
do_shm_rmid(ns, shp);
+ total++;
}
mutex_unlock(&shm_ids(ns).mutex);
- ipc_fini_ids(ns->ids[IPC_SHM_IDS]);
kfree(ns->ids[IPC_SHM_IDS]);
ns->ids[IPC_SHM_IDS] = NULL;
}
@@ -146,9 +150,9 @@
return 0;
}
-static inline struct shmid_kernel *shm_rmid(struct ipc_namespace *ns, int id)
+static inline void shm_rmid(struct ipc_namespace *ns, struct shmid_kernel *s)
{
- return (struct shmid_kernel *)ipc_rmid(&shm_ids(ns), id);
+ ipc_rmid(&shm_ids(ns), &s->shm_perm);
}
static inline int shm_addid(struct ipc_namespace *ns, struct shmid_kernel *shp)
@@ -184,7 +188,7 @@
static void shm_destroy(struct ipc_namespace *ns, struct shmid_kernel *shp)
{
ns->shm_tot -= (shp->shm_segsz + PAGE_SIZE - 1) >> PAGE_SHIFT;
- shm_rmid(ns, shp->id);
+ shm_rmid(ns, shp);
shm_unlock(shp);
if (!is_file_hugepages(shp->shm_file))
shmem_lock(shp->shm_file, 0, shp->mlock_user);
@@ -398,17 +402,18 @@
shp->shm_ctim = get_seconds();
shp->shm_segsz = size;
shp->shm_nattch = 0;
- shp->id = shm_buildid(ns, id, shp->shm_perm.seq);
+ shp->shm_perm.id = shm_buildid(ns, id, shp->shm_perm.seq);
shp->shm_file = file;
/*
* shmid gets reported as "inode#" in /proc/pid/maps.
* proc-ps tools use this. Changing this will break them.
*/
- file->f_dentry->d_inode->i_ino = shp->id;
+ file->f_dentry->d_inode->i_ino = shp->shm_perm.id;
ns->shm_tot += numpages;
+ error = shp->shm_perm.id;
shm_unlock(shp);
- return shp->id;
+ return error;
no_id:
fput(file);
@@ -421,37 +426,52 @@
asmlinkage long sys_shmget (key_t key, size_t size, int shmflg)
{
struct shmid_kernel *shp;
- int err, id = 0;
+ int err;
struct ipc_namespace *ns;
ns = current->nsproxy->ipc_ns;
- mutex_lock(&shm_ids(ns).mutex);
+ err = idr_pre_get(&shm_ids(ns).ipcs_idr, GFP_KERNEL);
+
if (key == IPC_PRIVATE) {
- err = newseg(ns, key, shmflg, size);
- } else if ((id = ipc_findkey(&shm_ids(ns), key)) == -1) {
- if (!(shmflg & IPC_CREAT))
- err = -ENOENT;
- else
- err = newseg(ns, key, shmflg, size);
- } else if ((shmflg & IPC_CREAT) && (shmflg & IPC_EXCL)) {
- err = -EEXIST;
- } else {
- shp = shm_lock(ns, id);
- BUG_ON(shp==NULL);
- if (shp->shm_segsz < size)
- err = -EINVAL;
- else if (ipcperms(&shp->shm_perm, shmflg))
- err = -EACCES;
+ if (!err)
+ err = -ENOMEM;
else {
- int shmid = shm_buildid(ns, id, shp->shm_perm.seq);
- err = security_shm_associate(shp, shmflg);
- if (!err)
- err = shmid;
+ mutex_lock(&shm_ids(ns).mutex);
+ err = newseg(ns, key, shmflg, size);
+ mutex_unlock(&shm_ids(ns).mutex);
}
- shm_unlock(shp);
+ } else {
+ mutex_lock(&shm_ids(ns).mutex);
+ shp = (struct shmid_kernel *) ipc_findkey(&shm_ids(ns), key);
+ if (shp == NULL) {
+ if (!(shmflg & IPC_CREAT))
+ err = -ENOENT;
+ else if (!err)
+ err = -ENOMEM;
+ else
+ err = newseg(ns, key, shmflg, size);
+ } else {
+ /* shp has been locked by ipc_findkey() */
+
+ if ((shmflg & IPC_CREAT) && (shmflg & IPC_EXCL))
+ err = -EEXIST;
+ else {
+ if (shp->shm_segsz < size)
+ err = -EINVAL;
+ else if (ipcperms(&shp->shm_perm, shmflg))
+ err = -EACCES;
+ else {
+ err = security_shm_associate(shp,
+ shmflg);
+ if (!err)
+ err = shp->shm_perm.id;
+ }
+ }
+ shm_unlock(shp);
+ }
+ mutex_unlock(&shm_ids(ns).mutex);
}
- mutex_unlock(&shm_ids(ns).mutex);
return err;
}
@@ -550,17 +570,20 @@
static void shm_get_stat(struct ipc_namespace *ns, unsigned long *rss,
unsigned long *swp)
{
- int i;
+ int next_id;
+ int total, in_use;
*rss = 0;
*swp = 0;
- for (i = 0; i <= shm_ids(ns).max_id; i++) {
+ in_use = shm_ids(ns).in_use;
+
+ for (total = 0, next_id = 0; total < in_use; next_id++) {
struct shmid_kernel *shp;
struct inode *inode;
- shp = shm_get(ns, i);
- if(!shp)
+ shp = shm_get(ns, next_id);
+ if (shp == NULL)
continue;
inode = shp->shm_file->f_path.dentry->d_inode;
@@ -575,6 +598,8 @@
*swp += info->swapped;
spin_unlock(&info->lock);
}
+
+ total++;
}
}
@@ -611,7 +636,7 @@
if(copy_shminfo_to_user (buf, &shminfo, version))
return -EFAULT;
/* reading a integer is always atomic */
- err= shm_ids(ns).max_id;
+ err = ipc_get_maxid(&shm_ids(ns));
if(err<0)
err = 0;
goto out;
@@ -631,7 +656,7 @@
shm_info.shm_tot = ns->shm_tot;
shm_info.swap_attempts = 0;
shm_info.swap_successes = 0;
- err = shm_ids(ns).max_id;
+ err = ipc_get_maxid(&shm_ids(ns));
mutex_unlock(&shm_ids(ns).mutex);
if(copy_to_user (buf, &shm_info, sizeof(shm_info))) {
err = -EFAULT;
@@ -651,11 +676,8 @@
if(shp==NULL) {
err = -EINVAL;
goto out;
- } else if(cmd==SHM_STAT) {
- err = -EINVAL;
- if (shmid > shm_ids(ns).max_id)
- goto out_unlock;
- result = shm_buildid(ns, shmid, shp->shm_perm.seq);
+ } else if (cmd == SHM_STAT) {
+ result = shp->shm_perm.id;
} else {
err = shm_checkid(ns, shp,shmid);
if(err)
@@ -925,7 +947,7 @@
file->private_data = sfd;
file->f_mapping = shp->shm_file->f_mapping;
- sfd->id = shp->id;
+ sfd->id = shp->shm_perm.id;
sfd->ns = get_ipc_ns(ns);
sfd->file = shp->shm_file;
sfd->vm_ops = NULL;
@@ -1094,7 +1116,7 @@
format = BIG_STRING;
return seq_printf(s, format,
shp->shm_perm.key,
- shp->id,
+ shp->shm_perm.id,
shp->shm_perm.mode,
shp->shm_segsz,
shp->shm_cprid,
diff --git a/ipc/util.c b/ipc/util.c
index 44e5135..2a20587 100644
--- a/ipc/util.c
+++ b/ipc/util.c
@@ -129,23 +129,16 @@
/**
* ipc_init_ids - initialise IPC identifiers
* @ids: Identifier set
- * @size: Number of identifiers
*
- * Given a size for the ipc identifier range (limited below IPCMNI)
- * set up the sequence range to use then allocate and initialise the
- * array itself.
+ * Set up the sequence range to use for the ipc identifier range (limited
+ * below IPCMNI) then initialise the ids idr.
*/
-void ipc_init_ids(struct ipc_ids* ids, int size)
+void ipc_init_ids(struct ipc_ids *ids)
{
- int i;
-
mutex_init(&ids->mutex);
- if(size > IPCMNI)
- size = IPCMNI;
ids->in_use = 0;
- ids->max_id = -1;
ids->seq = 0;
{
int seq_limit = INT_MAX/SEQ_MULTIPLIER;
@@ -155,17 +148,7 @@
ids->seq_max = seq_limit;
}
- ids->entries = ipc_rcu_alloc(sizeof(struct kern_ipc_perm *)*size +
- sizeof(struct ipc_id_ary));
-
- if(ids->entries == NULL) {
- printk(KERN_ERR "ipc_init_ids() failed, ipc service disabled.\n");
- size = 0;
- ids->entries = &ids->nullentry;
- }
- ids->entries->size = size;
- for(i=0;i<size;i++)
- ids->entries->p[i] = NULL;
+ idr_init(&ids->ipcs_idr);
}
#ifdef CONFIG_PROC_FS
@@ -209,72 +192,73 @@
* @key: The key to find
*
* Requires ipc_ids.mutex locked.
- * Returns the identifier if found or -1 if not.
+ * Returns the LOCKED pointer to the ipc structure if found or NULL
+ * if not.
+ * If key is found ipc contains its ipc structure
*/
-int ipc_findkey(struct ipc_ids* ids, key_t key)
+struct kern_ipc_perm *ipc_findkey(struct ipc_ids *ids, key_t key)
{
- int id;
- struct kern_ipc_perm* p;
- int max_id = ids->max_id;
+ struct kern_ipc_perm *ipc;
+ int next_id;
+ int total;
- /*
- * rcu_dereference() is not needed here
- * since ipc_ids.mutex is held
- */
- for (id = 0; id <= max_id; id++) {
- p = ids->entries->p[id];
- if(p==NULL)
+ for (total = 0, next_id = 0; total < ids->in_use; next_id++) {
+ ipc = idr_find(&ids->ipcs_idr, next_id);
+
+ if (ipc == NULL)
continue;
- if (key == p->key)
- return id;
+
+ if (ipc->key != key) {
+ total++;
+ continue;
+ }
+
+ ipc_lock_by_ptr(ipc);
+ return ipc;
}
- return -1;
+
+ return NULL;
}
-/*
- * Requires ipc_ids.mutex locked
+/**
+ * ipc_get_maxid - get the last assigned id
+ * @ids: IPC identifier set
+ *
+ * Called with ipc_ids.mutex held.
*/
-static int grow_ary(struct ipc_ids* ids, int newsize)
+
+int ipc_get_maxid(struct ipc_ids *ids)
{
- struct ipc_id_ary* new;
- struct ipc_id_ary* old;
- int i;
- int size = ids->entries->size;
+ struct kern_ipc_perm *ipc;
+ int max_id = -1;
+ int total, id;
- if(newsize > IPCMNI)
- newsize = IPCMNI;
- if(newsize <= size)
- return newsize;
+ if (ids->in_use == 0)
+ return -1;
- new = ipc_rcu_alloc(sizeof(struct kern_ipc_perm *)*newsize +
- sizeof(struct ipc_id_ary));
- if(new == NULL)
- return size;
- new->size = newsize;
- memcpy(new->p, ids->entries->p, sizeof(struct kern_ipc_perm *)*size);
- for(i=size;i<newsize;i++) {
- new->p[i] = NULL;
+ if (ids->in_use == IPCMNI)
+ return IPCMNI - 1;
+
+ /* Look for the last assigned id */
+ total = 0;
+ for (id = 0; id < IPCMNI && total < ids->in_use; id++) {
+ ipc = idr_find(&ids->ipcs_idr, id);
+ if (ipc != NULL) {
+ max_id = id;
+ total++;
+ }
}
- old = ids->entries;
-
- /*
- * Use rcu_assign_pointer() to make sure the memcpyed contents
- * of the new array are visible before the new array becomes visible.
- */
- rcu_assign_pointer(ids->entries, new);
-
- __ipc_fini_ids(ids, old);
- return newsize;
+ return max_id;
}
/**
* ipc_addid - add an IPC identifier
* @ids: IPC identifier set
* @new: new IPC permission set
- * @size: new size limit for the id array
+ * @size: limit for the number of used ids
*
- * Add an entry 'new' to the IPC arrays. The permissions object is
+ * Add an entry 'new' to the IPC idr. The permissions object is
* initialised and the first free entry is set up and the id assigned
* is returned. The list is returned in a locked state on success.
* On failure the list is not locked and -1 is returned.
@@ -284,23 +268,23 @@
int ipc_addid(struct ipc_ids* ids, struct kern_ipc_perm* new, int size)
{
- int id;
-
- size = grow_ary(ids,size);
+ int id, err;
/*
* rcu_dereference()() is not needed here since
* ipc_ids.mutex is held
*/
- for (id = 0; id < size; id++) {
- if(ids->entries->p[id] == NULL)
- goto found;
- }
- return -1;
-found:
+ if (size > IPCMNI)
+ size = IPCMNI;
+
+ if (ids->in_use >= size)
+ return -1;
+
+ err = idr_get_new(&ids->ipcs_idr, new, &id);
+ if (err)
+ return -1;
+
ids->in_use++;
- if (id > ids->max_id)
- ids->max_id = id;
new->cuid = new->uid = current->euid;
new->gid = new->cgid = current->egid;
@@ -313,48 +297,32 @@
new->deleted = 0;
rcu_read_lock();
spin_lock(&new->lock);
- ids->entries->p[id] = new;
return id;
}
/**
* ipc_rmid - remove an IPC identifier
* @ids: identifier set
- * @id: Identifier to remove
+ * @id: ipc perm structure containing the identifier to remove
*
* The identifier must be valid, and in use. The kernel will panic if
* fed an invalid identifier. The entry is removed and internal
- * variables recomputed. The object associated with the identifier
- * is returned.
- * ipc_ids.mutex and the spinlock for this ID is hold before this function
- * is called, and remain locked on the exit.
+ * variables recomputed.
+ * ipc_ids.mutex and the spinlock for this ID are held before this
+ * function is called, and remain locked on the exit.
*/
-struct kern_ipc_perm* ipc_rmid(struct ipc_ids* ids, int id)
+void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp)
{
- struct kern_ipc_perm* p;
- int lid = id % SEQ_MULTIPLIER;
- BUG_ON(lid >= ids->entries->size);
+ int lid = ipcp->id % SEQ_MULTIPLIER;
- /*
- * do not need a rcu_dereference()() here to force ordering
- * on Alpha, since the ipc_ids.mutex is held.
- */
- p = ids->entries->p[lid];
- ids->entries->p[lid] = NULL;
- BUG_ON(p==NULL);
+ idr_remove(&ids->ipcs_idr, lid);
+
ids->in_use--;
- if (lid == ids->max_id) {
- do {
- lid--;
- if(lid == -1)
- break;
- } while (ids->entries->p[lid] == NULL);
- ids->max_id = lid;
- }
- p->deleted = 1;
- return p;
+ ipcp->deleted = 1;
+
+ return;
}
/**
@@ -613,33 +581,26 @@
* if in the future ipc_get() is used by other places without ipc_ids.mutex
* down, then ipc_get() needs read memery barriers as ipc_lock() does.
*/
-struct kern_ipc_perm* ipc_get(struct ipc_ids* ids, int id)
+struct kern_ipc_perm *ipc_get(struct ipc_ids *ids, int id)
{
- struct kern_ipc_perm* out;
+ struct kern_ipc_perm *out;
int lid = id % SEQ_MULTIPLIER;
- if(lid >= ids->entries->size)
- return NULL;
- out = ids->entries->p[lid];
+ out = idr_find(&ids->ipcs_idr, lid);
return out;
}
-struct kern_ipc_perm* ipc_lock(struct ipc_ids* ids, int id)
+struct kern_ipc_perm *ipc_lock(struct ipc_ids *ids, int id)
{
- struct kern_ipc_perm* out;
+ struct kern_ipc_perm *out;
int lid = id % SEQ_MULTIPLIER;
- struct ipc_id_ary* entries;
rcu_read_lock();
- entries = rcu_dereference(ids->entries);
- if(lid >= entries->size) {
+ out = idr_find(&ids->ipcs_idr, lid);
+ if (out == NULL) {
rcu_read_unlock();
return NULL;
}
- out = entries->p[lid];
- if(out == NULL) {
- rcu_read_unlock();
- return NULL;
- }
+
spin_lock(&out->lock);
/* ipc_rmid() may have already freed the ID while ipc_lock
@@ -650,6 +611,7 @@
rcu_read_unlock();
return NULL;
}
+
return out;
}
@@ -707,27 +669,30 @@
struct ipc_proc_iface *iface;
};
-static void *sysvipc_proc_next(struct seq_file *s, void *it, loff_t *pos)
+/*
+ * This routine locks the ipc structure found at least at position pos.
+ */
+struct kern_ipc_perm *sysvipc_find_ipc(struct ipc_ids *ids, loff_t pos,
+ loff_t *new_pos)
{
- struct ipc_proc_iter *iter = s->private;
- struct ipc_proc_iface *iface = iter->iface;
- struct kern_ipc_perm *ipc = it;
- loff_t p;
- struct ipc_ids *ids;
+ struct kern_ipc_perm *ipc;
+ int total, id;
- ids = iter->ns->ids[iface->ids];
+ total = 0;
+ for (id = 0; id < pos && total < ids->in_use; id++) {
+ ipc = idr_find(&ids->ipcs_idr, id);
+ if (ipc != NULL)
+ total++;
+ }
- /* If we had an ipc id locked before, unlock it */
- if (ipc && ipc != SEQ_START_TOKEN)
- ipc_unlock(ipc);
+ if (total >= ids->in_use)
+ return NULL;
- /*
- * p = *pos - 1 (because id 0 starts at position 1)
- * + 1 (because we increment the position by one)
- */
- for (p = *pos; p <= ids->max_id; p++) {
- if ((ipc = ipc_lock(ids, p)) != NULL) {
- *pos = p + 1;
+ for ( ; pos < IPCMNI; pos++) {
+ ipc = idr_find(&ids->ipcs_idr, pos);
+ if (ipc != NULL) {
+ *new_pos = pos + 1;
+ ipc_lock_by_ptr(ipc);
return ipc;
}
}
@@ -736,6 +701,19 @@
return NULL;
}
+static void *sysvipc_proc_next(struct seq_file *s, void *it, loff_t *pos)
+{
+ struct ipc_proc_iter *iter = s->private;
+ struct ipc_proc_iface *iface = iter->iface;
+ struct kern_ipc_perm *ipc = it;
+
+ /* If we had an ipc id locked before, unlock it */
+ if (ipc && ipc != SEQ_START_TOKEN)
+ ipc_unlock(ipc);
+
+ return sysvipc_find_ipc(iter->ns->ids[iface->ids], *pos, pos);
+}
+
/*
* File positions: pos 0 -> header, pos n -> ipc id + 1.
* SeqFile iterator: iterator value locked shp or SEQ_TOKEN_START.
@@ -744,8 +722,6 @@
{
struct ipc_proc_iter *iter = s->private;
struct ipc_proc_iface *iface = iter->iface;
- struct kern_ipc_perm *ipc;
- loff_t p;
struct ipc_ids *ids;
ids = iter->ns->ids[iface->ids];
@@ -765,13 +741,7 @@
return SEQ_START_TOKEN;
/* Find the (pos-1)th ipc */
- for (p = *pos - 1; p <= ids->max_id; p++) {
- if ((ipc = ipc_lock(ids, p)) != NULL) {
- *pos = p + 1;
- return ipc;
- }
- }
- return NULL;
+ return sysvipc_find_ipc(ids, *pos - 1, pos);
}
static void sysvipc_proc_stop(struct seq_file *s, void *it)
diff --git a/ipc/util.h b/ipc/util.h
index 333e891..c906326 100644
--- a/ipc/util.h
+++ b/ipc/util.h
@@ -10,6 +10,8 @@
#ifndef _IPC_UTIL_H
#define _IPC_UTIL_H
+#include <linux/idr.h>
+
#define USHRT_MAX 0xffff
#define SEQ_MULTIPLIER (IPCMNI)
@@ -25,24 +27,17 @@
void msg_exit_ns(struct ipc_namespace *ns);
void shm_exit_ns(struct ipc_namespace *ns);
-struct ipc_id_ary {
- int size;
- struct kern_ipc_perm *p[0];
-};
-
struct ipc_ids {
int in_use;
- int max_id;
unsigned short seq;
unsigned short seq_max;
struct mutex mutex;
- struct ipc_id_ary nullentry;
- struct ipc_id_ary* entries;
+ struct idr ipcs_idr;
};
struct seq_file;
-void ipc_init_ids(struct ipc_ids *ids, int size);
+void ipc_init_ids(struct ipc_ids *);
#ifdef CONFIG_PROC_FS
void __init ipc_init_proc_interface(const char *path, const char *header,
int ids, int (*show)(struct seq_file *, void *));
@@ -55,11 +50,12 @@
#define IPC_SHM_IDS 2
/* must be called with ids->mutex acquired.*/
-int ipc_findkey(struct ipc_ids* ids, key_t key);
-int ipc_addid(struct ipc_ids* ids, struct kern_ipc_perm* new, int size);
+struct kern_ipc_perm *ipc_findkey(struct ipc_ids *ids, key_t key);
+int ipc_addid(struct ipc_ids *, struct kern_ipc_perm *, int);
+int ipc_get_maxid(struct ipc_ids *);
/* must be called with both locks acquired. */
-struct kern_ipc_perm* ipc_rmid(struct ipc_ids* ids, int id);
+void ipc_rmid(struct ipc_ids *, struct kern_ipc_perm *);
int ipcperms (struct kern_ipc_perm *ipcp, short flg);
@@ -79,18 +75,6 @@
void ipc_rcu_getref(void *ptr);
void ipc_rcu_putref(void *ptr);
-static inline void __ipc_fini_ids(struct ipc_ids *ids,
- struct ipc_id_ary *entries)
-{
- if (entries != &ids->nullentry)
- ipc_rcu_putref(entries);
-}
-
-static inline void ipc_fini_ids(struct ipc_ids *ids)
-{
- __ipc_fini_ids(ids, ids->entries);
-}
-
struct kern_ipc_perm* ipc_get(struct ipc_ids* ids, int id);
struct kern_ipc_perm* ipc_lock(struct ipc_ids* ids, int id);
void ipc_lock_by_ptr(struct kern_ipc_perm *ipcp);