static int __sc_hcreate(struct task_struct *curr, struct pt_regs *regs)
{
unsigned log2psize;
vrtx_hdesc_t hdesc;
vrtxheap_t *heap;
u_long heapsize;
int err, hid;
spl_t s;
if (!__xn_access_ok
(curr, VERIFY_WRITE, __xn_reg_arg3(regs), sizeof(hdesc)))
return -EFAULT;
/* Size of heap space. */
heapsize = __xn_reg_arg1(regs);
/* Page size. */
log2psize = (int)__xn_reg_arg2(regs);
hid = sc_hcreate(NULL, heapsize, log2psize, &err);
if (err)
return err;
xnlock_get_irqsave(&nklock, s);
heap = xnmap_fetch(vrtx_heap_idmap, hid);
if (heap) { /* Paranoid. */
heap->mm = curr->mm;
hdesc.hid = hid;
hdesc.hcb = &heap->sysheap;
hdesc.hsize = xnheap_extentsize(&heap->sysheap);
xnlock_put_irqrestore(&nklock, s);
__xn_copy_to_user(curr, (void __user *)__xn_reg_arg3(regs),
&hdesc, sizeof(hdesc));
} else {
xnlock_put_irqrestore(&nklock, s);
err = ER_ID;
}
return err;
}
/**
* Truncate a file or shared memory object to a specified length.
*
* When used in kernel-space, this service set to @a len the size of a shared
* memory object opened with the shm_open() service. In user-space this service
* falls back to Linux regular ftruncate service for file descriptors not
* obtained with shm_open(). When this service is used to increase the size of a
* shared memory object, the added space is zero-filled.
*
* Shared memory are suitable for direct memory access (allocated in physically
* contiguous memory) if O_DIRECT was passed to shm_open.
*
* Shared memory objects may only be resized if they are not currently mapped.
*
* @param fd file descriptor;
*
* @param len new length of the underlying file or shared memory object.
*
* @retval 0 on success;
* @retval -1 with @a errno set if:
* - EBADF, @a fd is not a valid file descriptor;
* - EPERM, the caller context is invalid;
* - EINVAL, the specified length is invalid;
* - EINVAL, the architecture can not honour the O_DIRECT flag;
* - EINTR, this service was interrupted by a signal;
* - EBUSY, @a fd is a shared memory object descriptor and the underlying shared
* memory is currently mapped;
* - EFBIG, allocation of system memory failed.
*
* @par Valid contexts:
* - kernel module initialization or cleanup routine;
* - user-space thread (Xenomai threads switch to secondary mode).
*
* @see
* <a href="http://www.opengroup.org/onlinepubs/000095399/functions/ftruncate.html">
* Specification.</a>
*
*/
int ftruncate(int fd, off_t len)
{
unsigned desc_flags;
pse51_desc_t *desc;
pse51_shm_t *shm;
int err;
spl_t s;
xnlock_get_irqsave(&nklock, s);
shm = pse51_shm_get(&desc, fd, 1);
if (IS_ERR(shm)) {
err = -PTR_ERR(shm);
xnlock_put_irqrestore(&nklock, s);
goto error;
}
if (xnpod_asynch_p() || !xnpod_root_p()) {
err = EPERM;
xnlock_put_irqrestore(&nklock, s);
goto err_shm_put;
}
if (len < 0) {
err = EINVAL;
xnlock_put_irqrestore(&nklock, s);
goto err_shm_put;
}
desc_flags = pse51_desc_getflags(desc);
xnlock_put_irqrestore(&nklock, s);
if (down_interruptible(&shm->maplock)) {
err = EINTR;
goto err_shm_put;
}
/* Allocate one more page for alignment (the address returned by mmap
must be aligned on a page boundary). */
if (len)
#ifdef CONFIG_XENO_OPT_PERVASIVE
len = xnheap_rounded_size(len + PAGE_SIZE, PAGE_SIZE);
#else /* !CONFIG_XENO_OPT_PERVASIVE */
len = xnheap_rounded_size(len + PAGE_SIZE, XNHEAP_PAGE_SIZE);
#endif /* !CONFIG_XENO_OPT_PERVASIVE */
err = 0;
if (emptyq_p(&shm->mappings)) {
/* Temporary storage, in order to preserve the memory contents upon
resizing, if possible. */
void *addr = NULL;
size_t size = 0;
if (shm->addr) {
if (len == xnheap_extentsize(&shm->heapbase)) {
/* Size unchanged, skip copy and reinit. */
err = 0;
goto err_up;
}
size = xnheap_max_contiguous(&shm->heapbase);
addr = xnarch_alloc_host_mem(size);
if (!addr) {
err = ENOMEM;
goto err_up;
}
memcpy(addr, shm->addr, size);
xnheap_free(&shm->heapbase, shm->addr);
xnheap_destroy_mapped(&shm->heapbase, NULL, NULL);
shm->addr = NULL;
shm->size = 0;
}
if (len) {
int flags = XNARCH_SHARED_HEAP_FLAGS |
((desc_flags & O_DIRECT) ? GFP_DMA : 0);
err = -xnheap_init_mapped(&shm->heapbase, len, flags);
if (err)
goto err_up;
xnheap_set_label(&shm->heapbase,
"posix shm: %s", shm->nodebase.name);
shm->size = xnheap_max_contiguous(&shm->heapbase);
shm->addr = xnheap_alloc(&shm->heapbase, shm->size);
/* Required. */
memset(shm->addr, '\0', shm->size);
/* Copy the previous contents. */
if (addr)
memcpy(shm->addr, addr,
shm->size < size ? shm->size : size);
shm->size -= PAGE_SIZE;
}
if (addr)
xnarch_free_host_mem(addr, size);
} else if (len != xnheap_extentsize(&shm->heapbase))
err = EBUSY;
err_up:
up(&shm->maplock);
err_shm_put:
pse51_shm_put(shm, 1);
if (!err)
return 0;
error:
thread_set_errno(err == ENOMEM ? EFBIG : err);
return -1;
}
static int __sc_pcreate(struct task_struct *curr, struct pt_regs *regs)
{
u_long ptsize, bsize;
vrtx_pdesc_t pdesc;
xnheap_t *ptheap;
vrtxpt_t *pt;
int err, pid;
char *ptaddr;
spl_t s;
if (!__xn_access_ok
(curr, VERIFY_WRITE, __xn_reg_arg4(regs), sizeof(pdesc)))
return -EFAULT;
ptheap = (xnheap_t *)xnmalloc(sizeof(*ptheap));
if (!ptheap)
return ER_MEM;
/* Suggested partition ID. */
pid = __xn_reg_arg1(regs);
/* Size of partition space -- account for the heap mgmt overhead. */
ptsize = __xn_reg_arg2(regs);
/* Shared heaps use the natural page size (PAGE_SIZE) */
ptsize = xnheap_rounded_size(ptsize, PAGE_SIZE);
/* Block size. */
bsize = __xn_reg_arg3(regs);
err = xnheap_init_mapped(ptheap, ptsize, 0);
if (err)
goto free_heap;
/* Allocate the partition space as a single shared heap block. */
ptaddr = xnheap_alloc(ptheap, ptsize);
pid = sc_pcreate(pid, ptaddr, ptsize, bsize, &err);
if (err)
goto unmap_pt;
xnlock_get_irqsave(&nklock, s);
pt = xnmap_fetch(vrtx_pt_idmap, pid);
if (pt) { /* Paranoid. */
pt->mm = curr->mm;
pt->sysheap = ptheap;
pdesc.pid = pid;
pdesc.ptcb = ptheap;
pdesc.ptsize = xnheap_extentsize(ptheap);
xnlock_put_irqrestore(&nklock, s);
__xn_copy_to_user(curr, (void __user *)__xn_reg_arg4(regs),
&pdesc, sizeof(pdesc));
return 0;
}
xnlock_put_irqrestore(&nklock, s);
err = ER_PID;
unmap_pt:
xnheap_destroy_mapped(ptheap, NULL, NULL);
free_heap:
xnfree(ptheap);
return err;
}
