/*
* Fill as many pages as vm_fault has allocated for us.
*/
static int
phys_pager_getpages(vm_object_t object, vm_page_t *m, int count, int reqpage)
{
int i;
VM_OBJECT_ASSERT_WLOCKED(object);
for (i = 0; i < count; i++) {
if (m[i]->valid == 0) {
if ((m[i]->flags & PG_ZERO) == 0)
pmap_zero_page(m[i]);
m[i]->valid = VM_PAGE_BITS_ALL;
}
KASSERT(m[i]->valid == VM_PAGE_BITS_ALL,
("phys_pager_getpages: partially valid page %p", m[i]));
KASSERT(m[i]->dirty == 0,
("phys_pager_getpages: dirty page %p", m[i]));
/* The requested page must remain busy, the others not. */
if (i == reqpage) {
vm_page_lock(m[i]);
vm_page_flash(m[i]);
vm_page_unlock(m[i]);
} else
vm_page_xunbusy(m[i]);
}
return (VM_PAGER_OK);
}
int ttm_tt_swapin(struct ttm_tt *ttm)
{
vm_object_t obj;
vm_page_t from_page, to_page;
int i, ret, rv;
obj = ttm->swap_storage;
VM_OBJECT_WLOCK(obj);
vm_object_pip_add(obj, 1);
for (i = 0; i < ttm->num_pages; ++i) {
from_page = vm_page_grab(obj, i, VM_ALLOC_NORMAL);
if (from_page->valid != VM_PAGE_BITS_ALL) {
if (vm_pager_has_page(obj, i, NULL, NULL)) {
rv = vm_pager_get_pages(obj, &from_page, 1, 0);
if (rv != VM_PAGER_OK) {
vm_page_lock(from_page);
vm_page_free(from_page);
vm_page_unlock(from_page);
ret = -EIO;
goto err_ret;
}
} else
vm_page_zero_invalid(from_page, TRUE);
}
vm_page_xunbusy(from_page);
to_page = ttm->pages[i];
if (unlikely(to_page == NULL)) {
ret = -ENOMEM;
goto err_ret;
}
pmap_copy_page(from_page, to_page);
}
vm_object_pip_wakeup(obj);
VM_OBJECT_WUNLOCK(obj);
if (!(ttm->page_flags & TTM_PAGE_FLAG_PERSISTENT_SWAP))
vm_object_deallocate(obj);
ttm->swap_storage = NULL;
ttm->page_flags &= ~TTM_PAGE_FLAG_SWAPPED;
return (0);
err_ret:
vm_object_pip_wakeup(obj);
VM_OBJECT_WUNLOCK(obj);
return (ret);
}
int ttm_tt_swapout(struct ttm_tt *ttm, vm_object_t persistent_swap_storage)
{
vm_object_t obj;
vm_page_t from_page, to_page;
int i;
MPASS(ttm->state == tt_unbound || ttm->state == tt_unpopulated);
MPASS(ttm->caching_state == tt_cached);
if (persistent_swap_storage == NULL) {
obj = vm_pager_allocate(OBJT_SWAP, NULL,
IDX_TO_OFF(ttm->num_pages), VM_PROT_DEFAULT, 0,
curthread->td_ucred);
if (obj == NULL) {
printf("[TTM] Failed allocating swap storage\n");
return (-ENOMEM);
}
} else
obj = persistent_swap_storage;
VM_OBJECT_WLOCK(obj);
vm_object_pip_add(obj, 1);
for (i = 0; i < ttm->num_pages; ++i) {
from_page = ttm->pages[i];
if (unlikely(from_page == NULL))
continue;
to_page = vm_page_grab(obj, i, VM_ALLOC_NORMAL);
pmap_copy_page(from_page, to_page);
to_page->valid = VM_PAGE_BITS_ALL;
vm_page_dirty(to_page);
vm_page_xunbusy(to_page);
}
vm_object_pip_wakeup(obj);
VM_OBJECT_WUNLOCK(obj);
ttm->bdev->driver->ttm_tt_unpopulate(ttm);
ttm->swap_storage = obj;
ttm->page_flags |= TTM_PAGE_FLAG_SWAPPED;
if (persistent_swap_storage != NULL)
ttm->page_flags |= TTM_PAGE_FLAG_PERSISTENT_SWAP;
return (0);
}
int
exec_map_first_page(struct image_params *imgp)
{
int rv, i, after, initial_pagein;
vm_page_t ma[VM_INITIAL_PAGEIN];
vm_object_t object;
if (imgp->firstpage != NULL)
exec_unmap_first_page(imgp);
object = imgp->vp->v_object;
if (object == NULL)
return (EACCES);
VM_OBJECT_WLOCK(object);
#if VM_NRESERVLEVEL > 0
vm_object_color(object, 0);
#endif
ma[0] = vm_page_grab(object, 0, VM_ALLOC_NORMAL | VM_ALLOC_NOBUSY);
if (ma[0]->valid != VM_PAGE_BITS_ALL) {
vm_page_xbusy(ma[0]);
if (!vm_pager_has_page(object, 0, NULL, &after)) {
vm_page_lock(ma[0]);
vm_page_free(ma[0]);
vm_page_unlock(ma[0]);
VM_OBJECT_WUNLOCK(object);
return (EIO);
}
initial_pagein = min(after, VM_INITIAL_PAGEIN);
KASSERT(initial_pagein <= object->size,
("%s: initial_pagein %d object->size %ju",
__func__, initial_pagein, (uintmax_t )object->size));
for (i = 1; i < initial_pagein; i++) {
if ((ma[i] = vm_page_next(ma[i - 1])) != NULL) {
if (ma[i]->valid)
break;
if (!vm_page_tryxbusy(ma[i]))
break;
} else {
ma[i] = vm_page_alloc(object, i,
VM_ALLOC_NORMAL);
if (ma[i] == NULL)
break;
}
}
initial_pagein = i;
rv = vm_pager_get_pages(object, ma, initial_pagein, NULL, NULL);
if (rv != VM_PAGER_OK) {
for (i = 0; i < initial_pagein; i++) {
vm_page_lock(ma[i]);
vm_page_free(ma[i]);
vm_page_unlock(ma[i]);
}
VM_OBJECT_WUNLOCK(object);
return (EIO);
}
vm_page_xunbusy(ma[0]);
for (i = 1; i < initial_pagein; i++)
vm_page_readahead_finish(ma[i]);
}
vm_page_lock(ma[0]);
vm_page_hold(ma[0]);
vm_page_activate(ma[0]);
vm_page_unlock(ma[0]);
VM_OBJECT_WUNLOCK(object);
imgp->firstpage = sf_buf_alloc(ma[0], 0);
imgp->image_header = (char *)sf_buf_kva(imgp->firstpage);
return (0);
}
static int
shm_dotruncate(struct shmfd *shmfd, off_t length)
{
vm_object_t object;
vm_page_t m, ma[1];
vm_pindex_t idx, nobjsize;
vm_ooffset_t delta;
int base, rv;
object = shmfd->shm_object;
VM_OBJECT_WLOCK(object);
if (length == shmfd->shm_size) {
VM_OBJECT_WUNLOCK(object);
return (0);
}
nobjsize = OFF_TO_IDX(length + PAGE_MASK);
/* Are we shrinking? If so, trim the end. */
if (length < shmfd->shm_size) {
/*
* Disallow any requests to shrink the size if this
* object is mapped into the kernel.
*/
if (shmfd->shm_kmappings > 0) {
VM_OBJECT_WUNLOCK(object);
return (EBUSY);
}
/*
* Zero the truncated part of the last page.
*/
base = length & PAGE_MASK;
if (base != 0) {
idx = OFF_TO_IDX(length);
retry:
m = vm_page_lookup(object, idx);
if (m != NULL) {
if (vm_page_sleep_if_busy(m, "shmtrc"))
goto retry;
} else if (vm_pager_has_page(object, idx, NULL, NULL)) {
m = vm_page_alloc(object, idx, VM_ALLOC_NORMAL);
if (m == NULL) {
VM_OBJECT_WUNLOCK(object);
VM_WAIT;
VM_OBJECT_WLOCK(object);
goto retry;
} else if (m->valid != VM_PAGE_BITS_ALL) {
ma[0] = m;
rv = vm_pager_get_pages(object, ma, 1,
0);
m = vm_page_lookup(object, idx);
} else
/* A cached page was reactivated. */
rv = VM_PAGER_OK;
vm_page_lock(m);
if (rv == VM_PAGER_OK) {
vm_page_deactivate(m);
vm_page_unlock(m);
vm_page_xunbusy(m);
} else {
vm_page_free(m);
vm_page_unlock(m);
VM_OBJECT_WUNLOCK(object);
return (EIO);
}
}
if (m != NULL) {
pmap_zero_page_area(m, base, PAGE_SIZE - base);
KASSERT(m->valid == VM_PAGE_BITS_ALL,
("shm_dotruncate: page %p is invalid", m));
vm_page_dirty(m);
vm_pager_page_unswapped(m);
}
}
delta = ptoa(object->size - nobjsize);
/* Toss in memory pages. */
if (nobjsize < object->size)
vm_object_page_remove(object, nobjsize, object->size,
0);
/* Toss pages from swap. */
if (object->type == OBJT_SWAP)
swap_pager_freespace(object, nobjsize, delta);
/* Free the swap accounted for shm */
swap_release_by_cred(delta, object->cred);
object->charge -= delta;
} else {
/* Attempt to reserve the swap */
delta = ptoa(nobjsize - object->size);
if (!swap_reserve_by_cred(delta, object->cred)) {
VM_OBJECT_WUNLOCK(object);
return (ENOMEM);
}
object->charge += delta;
}
shmfd->shm_size = length;
mtx_lock(&shm_timestamp_lock);
vfs_timestamp(&shmfd->shm_ctime);
shmfd->shm_mtime = shmfd->shm_ctime;
mtx_unlock(&shm_timestamp_lock);
object->size = nobjsize;
VM_OBJECT_WUNLOCK(object);
return (0);
}
static int
uiomove_object_page(vm_object_t obj, size_t len, struct uio *uio)
{
vm_page_t m;
vm_pindex_t idx;
size_t tlen;
int error, offset, rv;
idx = OFF_TO_IDX(uio->uio_offset);
offset = uio->uio_offset & PAGE_MASK;
tlen = MIN(PAGE_SIZE - offset, len);
VM_OBJECT_WLOCK(obj);
/*
* Parallel reads of the page content from disk are prevented
* by exclusive busy.
*
* Although the tmpfs vnode lock is held here, it is
* nonetheless safe to sleep waiting for a free page. The
* pageout daemon does not need to acquire the tmpfs vnode
* lock to page out tobj's pages because tobj is a OBJT_SWAP
* type object.
*/
m = vm_page_grab(obj, idx, VM_ALLOC_NORMAL);
if (m->valid != VM_PAGE_BITS_ALL) {
if (vm_pager_has_page(obj, idx, NULL, NULL)) {
rv = vm_pager_get_pages(obj, &m, 1, 0);
m = vm_page_lookup(obj, idx);
if (m == NULL) {
printf(
"uiomove_object: vm_obj %p idx %jd null lookup rv %d\n",
obj, idx, rv);
VM_OBJECT_WUNLOCK(obj);
return (EIO);
}
if (rv != VM_PAGER_OK) {
printf(
"uiomove_object: vm_obj %p idx %jd valid %x pager error %d\n",
obj, idx, m->valid, rv);
vm_page_lock(m);
vm_page_free(m);
vm_page_unlock(m);
VM_OBJECT_WUNLOCK(obj);
return (EIO);
}
} else
vm_page_zero_invalid(m, TRUE);
}
vm_page_xunbusy(m);
vm_page_lock(m);
vm_page_hold(m);
vm_page_unlock(m);
VM_OBJECT_WUNLOCK(obj);
error = uiomove_fromphys(&m, offset, tlen, uio);
if (uio->uio_rw == UIO_WRITE && error == 0) {
VM_OBJECT_WLOCK(obj);
vm_page_dirty(m);
VM_OBJECT_WUNLOCK(obj);
}
vm_page_lock(m);
vm_page_unhold(m);
if (m->queue == PQ_NONE) {
vm_page_deactivate(m);
} else {
/* Requeue to maintain LRU ordering. */
vm_page_requeue(m);
}
vm_page_unlock(m);
return (error);
}