/*
* Get an sf_buf from the freelist. May block if none are available.
*/
struct sf_buf *
sf_buf_alloc(struct vm_page *m, int flags)
{
struct sf_head *hash_list;
struct sf_buf *sf;
int error;
#ifdef SFBUF_OPTIONAL_DIRECT_MAP
if (SFBUF_OPTIONAL_DIRECT_MAP)
return ((struct sf_buf *)m);
#endif
KASSERT(curthread->td_pinned > 0 || (flags & SFB_CPUPRIVATE) == 0,
("sf_buf_alloc(SFB_CPUPRIVATE): curthread not pinned"));
hash_list = &sf_buf_active[SF_BUF_HASH(m)];
mtx_lock(&sf_buf_lock);
LIST_FOREACH(sf, hash_list, list_entry) {
if (sf->m == m) {
sf->ref_count++;
if (sf->ref_count == 1) {
TAILQ_REMOVE(&sf_buf_freelist, sf, free_entry);
nsfbufsused++;
nsfbufspeak = imax(nsfbufspeak, nsfbufsused);
}
#if defined(SMP) && defined(SFBUF_CPUSET)
sf_buf_shootdown(sf, flags);
#endif
goto done;
}
}
while ((sf = TAILQ_FIRST(&sf_buf_freelist)) == NULL) {
if (flags & SFB_NOWAIT)
goto done;
sf_buf_alloc_want++;
SFSTAT_INC(sf_allocwait);
error = msleep(&sf_buf_freelist, &sf_buf_lock,
(flags & SFB_CATCH) ? PCATCH | PVM : PVM, "sfbufa", 0);
sf_buf_alloc_want--;
/*
* If we got a signal, don't risk going back to sleep.
*/
if (error)
goto done;
}
TAILQ_REMOVE(&sf_buf_freelist, sf, free_entry);
if (sf->m != NULL)
LIST_REMOVE(sf, list_entry);
LIST_INSERT_HEAD(hash_list, sf, list_entry);
sf->ref_count = 1;
sf->m = m;
nsfbufsused++;
nsfbufspeak = imax(nsfbufspeak, nsfbufsused);
sf_buf_map(sf, flags);
done:
mtx_unlock(&sf_buf_lock);
return (sf);
}
/*
* Get an sf_buf from the freelist. Will block if none are available.
*/
struct sf_buf *
sf_buf_alloc(struct vm_page *m, int flags)
{
struct sf_head *hash_list;
struct sf_buf *sf;
int error;
if (hw_direct_map) {
/* Shortcut the direct mapped case */
return ((struct sf_buf *)m);
}
hash_list = &sf_buf_active[SF_BUF_HASH(m)];
mtx_lock(&sf_buf_lock);
LIST_FOREACH(sf, hash_list, list_entry) {
if (sf->m == m) {
sf->ref_count++;
if (sf->ref_count == 1) {
TAILQ_REMOVE(&sf_buf_freelist, sf, free_entry);
nsfbufsused++;
nsfbufspeak = imax(nsfbufspeak, nsfbufsused);
}
goto done;
}
}
while ((sf = TAILQ_FIRST(&sf_buf_freelist)) == NULL) {
if (flags & SFB_NOWAIT)
goto done;
sf_buf_alloc_want++;
SFSTAT_INC(sf_allocwait);
error = msleep(&sf_buf_freelist, &sf_buf_lock,
(flags & SFB_CATCH) ? PCATCH | PVM : PVM, "sfbufa", 0);
sf_buf_alloc_want--;
/*
* If we got a signal, don't risk going back to sleep.
*/
if (error)
goto done;
}
TAILQ_REMOVE(&sf_buf_freelist, sf, free_entry);
if (sf->m != NULL)
LIST_REMOVE(sf, list_entry);
LIST_INSERT_HEAD(hash_list, sf, list_entry);
sf->ref_count = 1;
sf->m = m;
nsfbufsused++;
nsfbufspeak = imax(nsfbufspeak, nsfbufsused);
pmap_qenter(sf->kva, &sf->m, 1);
done:
mtx_unlock(&sf_buf_lock);
return (sf);
}
/*
* Get an sf_buf from the freelist. Will block if none are available.
*/
struct sf_buf *
sf_buf_alloc(struct vm_page *m, int flags)
{
#ifdef ARM_USE_SMALL_ALLOC
return ((struct sf_buf *)m);
#else
struct sf_head *hash_list;
struct sf_buf *sf;
int error;
hash_list = &sf_buf_active[SF_BUF_HASH(m)];
mtx_lock(&sf_buf_lock);
LIST_FOREACH(sf, hash_list, list_entry) {
if (sf->m == m) {
sf->ref_count++;
if (sf->ref_count == 1) {
TAILQ_REMOVE(&sf_buf_freelist, sf, free_entry);
nsfbufsused++;
nsfbufspeak = imax(nsfbufspeak, nsfbufsused);
}
goto done;
}
}
while ((sf = TAILQ_FIRST(&sf_buf_freelist)) == NULL) {
if (flags & SFB_NOWAIT)
goto done;
sf_buf_alloc_want++;
SFSTAT_INC(sf_allocwait);
error = msleep(&sf_buf_freelist, &sf_buf_lock,
(flags & SFB_CATCH) ? PCATCH | PVM : PVM, "sfbufa", 0);
sf_buf_alloc_want--;
/*
* If we got a signal, don't risk going back to sleep.
*/
if (error)
goto done;
}
TAILQ_REMOVE(&sf_buf_freelist, sf, free_entry);
if (sf->m != NULL)
LIST_REMOVE(sf, list_entry);
LIST_INSERT_HEAD(hash_list, sf, list_entry);
sf->ref_count = 1;
sf->m = m;
nsfbufsused++;
nsfbufspeak = imax(nsfbufspeak, nsfbufsused);
pmap_kenter(sf->kva, VM_PAGE_TO_PHYS(sf->m));
done:
mtx_unlock(&sf_buf_lock);
return (sf);
#endif
}
