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
vnode_pager_generic_getpages_done(struct buf *bp)
{
vm_object_t object;
off_t tfoff, nextoff;
int i, error;
error = (bp->b_ioflags & BIO_ERROR) != 0 ? EIO : 0;
object = bp->b_vp->v_object;
if (error == 0 && bp->b_bcount != bp->b_npages * PAGE_SIZE) {
if (!buf_mapped(bp)) {
bp->b_data = bp->b_kvabase;
pmap_qenter((vm_offset_t)bp->b_data, bp->b_pages,
bp->b_npages);
}
bzero(bp->b_data + bp->b_bcount,
PAGE_SIZE * bp->b_npages - bp->b_bcount);
}
if (buf_mapped(bp)) {
pmap_qremove((vm_offset_t)bp->b_data, bp->b_npages);
bp->b_data = unmapped_buf;
}
VM_OBJECT_WLOCK(object);
for (i = 0, tfoff = IDX_TO_OFF(bp->b_pages[0]->pindex);
i < bp->b_npages; i++, tfoff = nextoff) {
vm_page_t mt;
nextoff = tfoff + PAGE_SIZE;
mt = bp->b_pages[i];
if (nextoff <= object->un_pager.vnp.vnp_size) {
/*
* Read filled up entire page.
*/
mt->valid = VM_PAGE_BITS_ALL;
KASSERT(mt->dirty == 0,
("%s: page %p is dirty", __func__, mt));
KASSERT(!pmap_page_is_mapped(mt),
("%s: page %p is mapped", __func__, mt));
} else {
/*
* Read did not fill up entire page.
*
* Currently we do not set the entire page valid,
* we just try to clear the piece that we couldn't
* read.
*/
vm_page_set_valid_range(mt, 0,
object->un_pager.vnp.vnp_size - tfoff);
KASSERT((mt->dirty & vm_page_bits(0,
object->un_pager.vnp.vnp_size - tfoff)) == 0,
("%s: page %p is dirty", __func__, mt));
}
if (i < bp->b_pgbefore || i >= bp->b_npages - bp->b_pgafter)
vm_page_readahead_finish(mt);
}
VM_OBJECT_WUNLOCK(object);
if (error != 0)
printf("%s: I/O read error %d\n", __func__, error);
return (error);
}
/*
struct vnop_getpages_args {
struct vnode *a_vp;
vm_page_t *a_m;
int a_count;
int a_reqpage;
vm_ooffset_t a_offset;
};
*/
static int
fuse_vnop_getpages(struct vop_getpages_args *ap)
{
int i, error, nextoff, size, toff, count, npages;
struct uio uio;
struct iovec iov;
vm_offset_t kva;
struct buf *bp;
struct vnode *vp;
struct thread *td;
struct ucred *cred;
vm_page_t *pages;
FS_DEBUG2G("heh\n");
vp = ap->a_vp;
KASSERT(vp->v_object, ("objectless vp passed to getpages"));
td = curthread; /* XXX */
cred = curthread->td_ucred; /* XXX */
pages = ap->a_m;
count = ap->a_count;
if (!fsess_opt_mmap(vnode_mount(vp))) {
FS_DEBUG("called on non-cacheable vnode??\n");
return (VM_PAGER_ERROR);
}
npages = btoc(count);
/*
* If the requested page is partially valid, just return it and
* allow the pager to zero-out the blanks. Partially valid pages
* can only occur at the file EOF.
*/
VM_OBJECT_WLOCK(vp->v_object);
fuse_vm_page_lock_queues();
if (pages[ap->a_reqpage]->valid != 0) {
for (i = 0; i < npages; ++i) {
if (i != ap->a_reqpage) {
fuse_vm_page_lock(pages[i]);
vm_page_free(pages[i]);
fuse_vm_page_unlock(pages[i]);
}
}
fuse_vm_page_unlock_queues();
VM_OBJECT_WUNLOCK(vp->v_object);
return 0;
}
fuse_vm_page_unlock_queues();
VM_OBJECT_WUNLOCK(vp->v_object);
/*
* We use only the kva address for the buffer, but this is extremely
* convienient and fast.
*/
bp = getpbuf(&fuse_pbuf_freecnt);
kva = (vm_offset_t)bp->b_data;
pmap_qenter(kva, pages, npages);
PCPU_INC(cnt.v_vnodein);
PCPU_ADD(cnt.v_vnodepgsin, npages);
iov.iov_base = (caddr_t)kva;
iov.iov_len = count;
uio.uio_iov = &iov;
uio.uio_iovcnt = 1;
uio.uio_offset = IDX_TO_OFF(pages[0]->pindex);
uio.uio_resid = count;
uio.uio_segflg = UIO_SYSSPACE;
uio.uio_rw = UIO_READ;
uio.uio_td = td;
error = fuse_io_dispatch(vp, &uio, IO_DIRECT, cred);
pmap_qremove(kva, npages);
relpbuf(bp, &fuse_pbuf_freecnt);
if (error && (uio.uio_resid == count)) {
FS_DEBUG("error %d\n", error);
VM_OBJECT_WLOCK(vp->v_object);
fuse_vm_page_lock_queues();
for (i = 0; i < npages; ++i) {
if (i != ap->a_reqpage) {
fuse_vm_page_lock(pages[i]);
vm_page_free(pages[i]);
fuse_vm_page_unlock(pages[i]);
}
}
fuse_vm_page_unlock_queues();
VM_OBJECT_WUNLOCK(vp->v_object);
return VM_PAGER_ERROR;
}
/*
* Calculate the number of bytes read and validate only that number
* of bytes. Note that due to pending writes, size may be 0. This
* does not mean that the remaining data is invalid!
*/
size = count - uio.uio_resid;
VM_OBJECT_WLOCK(vp->v_object);
fuse_vm_page_lock_queues();
for (i = 0, toff = 0; i < npages; i++, toff = nextoff) {
vm_page_t m;
nextoff = toff + PAGE_SIZE;
m = pages[i];
if (nextoff <= size) {
/*
* Read operation filled an entire page
*/
m->valid = VM_PAGE_BITS_ALL;
KASSERT(m->dirty == 0,
("fuse_getpages: page %p is dirty", m));
} else if (size > toff) {
/*
* Read operation filled a partial page.
*/
m->valid = 0;
vm_page_set_valid_range(m, 0, size - toff);
KASSERT(m->dirty == 0,
("fuse_getpages: page %p is dirty", m));
} else {
/*
* Read operation was short. If no error occured
* we may have hit a zero-fill section. We simply
* leave valid set to 0.
*/
;
}
if (i != ap->a_reqpage)
vm_page_readahead_finish(m);
}
fuse_vm_page_unlock_queues();
VM_OBJECT_WUNLOCK(vp->v_object);
return 0;
}
