/*===========================================================================*
* do_shmat *
*===========================================================================*/
PUBLIC int do_shmat(message *m)
{
int id, flag;
vir_bytes addr;
void *ret;
struct shm_struct *shm;
id = m->SHMAT_ID;
addr = (vir_bytes) m->SHMAT_ADDR;
flag = m->SHMAT_FLAG;
if (addr && (addr % I386_PAGE_SIZE)) {
if (flag & SHM_RND)
addr -= (addr % I386_PAGE_SIZE);
else
return EINVAL;
}
if (!(shm = shm_find_id(id)))
return EINVAL;
if (flag & SHM_RDONLY)
flag = 0444;
else
flag = 0666;
if (!check_perm(&shm->shmid_ds.shm_perm, who_e, flag))
return EACCES;
ret = vm_remap(who_e, SELF_E, (void *)addr, (void *)shm->page,
shm->shmid_ds.shm_segsz);
if (ret == MAP_FAILED)
return ENOMEM;
shm->shmid_ds.shm_atime = time(NULL);
shm->shmid_ds.shm_lpid = getnpid(who_e);
/* nattach is updated lazily */
m->SHMAT_RETADDR = (long) ret;
return OK;
}
/*===========================================================================*
* do_shmat *
*===========================================================================*/
int do_shmat(message *m)
{
int id, flag;
vir_bytes addr;
void *ret;
struct shm_struct *shm;
id = m->m_lc_ipc_shmat.id;
addr = (vir_bytes) m->m_lc_ipc_shmat.addr;
flag = m->m_lc_ipc_shmat.flag;
if (addr && (addr % PAGE_SIZE)) {
if (flag & SHM_RND)
addr -= (addr % PAGE_SIZE);
else
return EINVAL;
}
if (!(shm = shm_find_id(id)))
return EINVAL;
if (flag & SHM_RDONLY)
flag = 0444;
else
flag = 0666;
if (!check_perm(&shm->shmid_ds.shm_perm, who_e, flag))
return EACCES;
ret = vm_remap(who_e, sef_self(), (void *)addr, (void *)shm->page,
shm->shmid_ds.shm_segsz);
if (ret == MAP_FAILED)
return ENOMEM;
shm->shmid_ds.shm_atime = time(NULL);
shm->shmid_ds.shm_lpid = getnpid(who_e);
/* nattach is updated lazily */
m->m_lc_ipc_shmat.retaddr = ret;
return OK;
}
/*===========================================================================*
* do_shmctl *
*===========================================================================*/
PUBLIC int do_shmctl(message *m)
{
int id = m->SHMCTL_ID;
int cmd = m->SHMCTL_CMD;
struct shmid_ds *ds = (struct shmid_ds *)m->SHMCTL_BUF;
struct shmid_ds tmp_ds;
struct shm_struct *shm;
struct shminfo sinfo;
struct shm_info s_info;
uid_t uid;
int r, i;
if (cmd == IPC_STAT)
update_refcount_and_destroy();
if ((cmd == IPC_STAT ||
cmd == IPC_SET ||
cmd == IPC_RMID) &&
!(shm = shm_find_id(id)))
return EINVAL;
switch (cmd) {
case IPC_STAT:
if (!ds)
return EFAULT;
/* check whether it has read permission */
if (!check_perm(&shm->shmid_ds.shm_perm, who_e, 0444))
return EACCES;
r = sys_datacopy(SELF_E, (vir_bytes)&shm->shmid_ds,
who_e, (vir_bytes)ds, sizeof(struct shmid_ds));
if (r != OK)
return EFAULT;
break;
case IPC_SET:
uid = getnuid(who_e);
if (uid != shm->shmid_ds.shm_perm.cuid &&
uid != shm->shmid_ds.shm_perm.uid &&
uid != 0)
return EPERM;
r = sys_datacopy(who_e, (vir_bytes)ds,
SELF_E, (vir_bytes)&tmp_ds, sizeof(struct shmid_ds));
if (r != OK)
return EFAULT;
shm->shmid_ds.shm_perm.uid = tmp_ds.shm_perm.uid;
shm->shmid_ds.shm_perm.gid = tmp_ds.shm_perm.gid;
shm->shmid_ds.shm_perm.mode &= ~0777;
shm->shmid_ds.shm_perm.mode |= tmp_ds.shm_perm.mode & 0666;
shm->shmid_ds.shm_ctime = time(NULL);
break;
case IPC_RMID:
uid = getnuid(who_e);
if (uid != shm->shmid_ds.shm_perm.cuid &&
uid != shm->shmid_ds.shm_perm.uid &&
uid != 0)
return EPERM;
shm->shmid_ds.shm_perm.mode |= SHM_DEST;
/* destroy if possible */
update_refcount_and_destroy();
break;
case IPC_INFO:
if (!ds)
return EFAULT;
sinfo.shmmax = (unsigned long) -1;
sinfo.shmmin = 1;
sinfo.shmmni = MAX_SHM_NR;
sinfo.shmseg = (unsigned long) -1;
sinfo.shmall = (unsigned long) -1;
r = sys_datacopy(SELF_E, (vir_bytes)&sinfo,
who_e, (vir_bytes)ds, sizeof(struct shminfo));
if (r != OK)
return EFAULT;
m->SHMCTL_RET = shm_list_nr - 1;
if (m->SHMCTL_RET < 0)
m->SHMCTL_RET = 0;
break;
case SHM_INFO:
if (!ds)
return EFAULT;
s_info.used_ids = shm_list_nr;
s_info.shm_tot = 0;
for (i = 0; i < shm_list_nr; i++)
s_info.shm_tot +=
shm_list[i].shmid_ds.shm_segsz/I386_PAGE_SIZE;
s_info.shm_rss = s_info.shm_tot;
s_info.shm_swp = 0;
s_info.swap_attempts = 0;
s_info.swap_successes = 0;
r = sys_datacopy(SELF_E, (vir_bytes)&s_info,
who_e, (vir_bytes)ds, sizeof(struct shm_info));
if (r != OK)
return EFAULT;
m->SHMCTL_RET = shm_list_nr - 1;
if (m->SHMCTL_RET < 0)
m->SHMCTL_RET = 0;
break;
case SHM_STAT:
if (id < 0 || id >= shm_list_nr)
return EINVAL;
shm = &shm_list[id];
r = sys_datacopy(SELF_E, (vir_bytes)&shm->shmid_ds,
who_e, (vir_bytes)ds, sizeof(struct shmid_ds));
if (r != OK)
return EFAULT;
m->SHMCTL_RET = shm->id;
break;
default:
return EINVAL;
}
return OK;
}
