static int grow_gnttab_list(unsigned int more_frames)
{
unsigned int new_nr_grant_frames, extra_entries, i;
unsigned int nr_glist_frames, new_nr_glist_frames;
new_nr_grant_frames = nr_grant_frames + more_frames;
extra_entries = more_frames * ENTRIES_PER_GRANT_FRAME;
nr_glist_frames = nr_freelist_frames(nr_grant_frames);
new_nr_glist_frames = nr_freelist_frames(new_nr_grant_frames);
for (i = nr_glist_frames; i < new_nr_glist_frames; i++) {
gnttab_list[i] = (grant_ref_t *)__get_free_page(GFP_ATOMIC);
if (!gnttab_list[i])
goto grow_nomem;
}
for (i = ENTRIES_PER_GRANT_FRAME * nr_grant_frames;
i < ENTRIES_PER_GRANT_FRAME * new_nr_grant_frames - 1; i++)
gnttab_entry(i) = i + 1;
gnttab_entry(i) = gnttab_free_head;
gnttab_free_head = ENTRIES_PER_GRANT_FRAME * nr_grant_frames;
gnttab_free_count += extra_entries;
nr_grant_frames = new_nr_grant_frames;
check_free_callbacks();
return 0;
grow_nomem:
for ( ; i >= nr_glist_frames; i--)
free_page((unsigned long) gnttab_list[i]);
return -ENOMEM;
}
void gnttab_request_free_callback(struct gnttab_free_callback *callback,
void (*fn)(void *), void *arg, u16 count)
{
unsigned long flags;
struct gnttab_free_callback *cb;
spin_lock_irqsave(&gnttab_list_lock, flags);
/* Check if the callback is already on the list */
cb = gnttab_free_callback_list;
while (cb) {
if (cb == callback)
goto out;
cb = cb->next;
}
callback->fn = fn;
callback->arg = arg;
callback->count = count;
callback->next = gnttab_free_callback_list;
gnttab_free_callback_list = callback;
check_free_callbacks();
out:
spin_unlock_irqrestore(&gnttab_list_lock, flags);
}
static void put_free_entry(grant_ref_t ref)
{
unsigned long flags;
spin_lock_irqsave(&gnttab_list_lock, flags);
gnttab_entry(ref) = gnttab_free_head;
gnttab_free_head = ref;
gnttab_free_count++;
check_free_callbacks();
spin_unlock_irqrestore(&gnttab_list_lock, flags);
}
static void
put_free_entry(grant_ref_t ref)
{
mtx_lock(&gnttab_list_lock);
gnttab_entry(ref) = gnttab_free_head;
gnttab_free_head = ref;
gnttab_free_count++;
check_free_callbacks();
mtx_unlock(&gnttab_list_lock);
}
void gnttab_request_free_callback(struct gnttab_free_callback *callback,
void (*fn)(void *), void *arg, u16 count)
{
unsigned long flags;
spin_lock_irqsave(&gnttab_list_lock, flags);
if (callback->next)
goto out;
callback->fn = fn;
callback->arg = arg;
callback->count = count;
callback->next = gnttab_free_callback_list;
gnttab_free_callback_list = callback;
check_free_callbacks();
out:
spin_unlock_irqrestore(&gnttab_list_lock, flags);
}
void
gnttab_request_free_callback(struct gnttab_free_callback *callback,
void (*fn)(void *), void *arg, uint16_t count)
{
mtx_lock(&gnttab_list_lock);
if (callback->next)
goto out;
callback->fn = fn;
callback->arg = arg;
callback->count = count;
callback->next = gnttab_free_callback_list;
gnttab_free_callback_list = callback;
check_free_callbacks();
out:
mtx_unlock(&gnttab_list_lock);
}
void gnttab_free_grant_references(grant_ref_t head)
{
grant_ref_t ref;
unsigned long flags;
int count = 1;
if (head == GNTTAB_LIST_END)
return;
spin_lock_irqsave(&gnttab_list_lock, flags);
ref = head;
while (gnttab_entry(ref) != GNTTAB_LIST_END) {
ref = gnttab_entry(ref);
count++;
}
gnttab_entry(ref) = gnttab_free_head;
gnttab_free_head = head;
gnttab_free_count += count;
check_free_callbacks();
spin_unlock_irqrestore(&gnttab_list_lock, flags);
}
void
gnttab_free_grant_references(grant_ref_t head)
{
grant_ref_t ref;
int count = 1;
if (head == GNTTAB_LIST_END)
return;
ref = head;
while (gnttab_entry(ref) != GNTTAB_LIST_END) {
ref = gnttab_entry(ref);
count++;
}
mtx_lock(&gnttab_list_lock);
gnttab_entry(ref) = gnttab_free_head;
gnttab_free_head = head;
gnttab_free_count += count;
check_free_callbacks();
mtx_unlock(&gnttab_list_lock);
}
static int grow_gnttab_list(unsigned int more_frames)
{
unsigned int new_nr_grant_frames, extra_entries, i;
unsigned int nr_glist_frames, new_nr_glist_frames;
BUG_ON(grefs_per_grant_frame == 0);
new_nr_grant_frames = nr_grant_frames + more_frames;
extra_entries = more_frames * grefs_per_grant_frame;
nr_glist_frames = (nr_grant_frames * grefs_per_grant_frame + RPP - 1) / RPP;
new_nr_glist_frames =
(new_nr_grant_frames * grefs_per_grant_frame + RPP - 1) / RPP;
for (i = nr_glist_frames; i < new_nr_glist_frames; i++) {
gnttab_list[i] = (grant_ref_t *)__get_free_page(GFP_ATOMIC);
if (!gnttab_list[i])
goto grow_nomem;
}
for (i = grefs_per_grant_frame * nr_grant_frames;
i < grefs_per_grant_frame * new_nr_grant_frames - 1; i++)
gnttab_entry(i) = i + 1;
gnttab_entry(i) = gnttab_free_head;
gnttab_free_head = grefs_per_grant_frame * nr_grant_frames;
gnttab_free_count += extra_entries;
nr_grant_frames = new_nr_grant_frames;
check_free_callbacks();
return 0;
grow_nomem:
while (i-- > nr_glist_frames)
free_page((unsigned long) gnttab_list[i]);
return -ENOMEM;
}
static int
grow_gnttab_list(unsigned int more_frames)
{
unsigned int new_nr_grant_frames, extra_entries, i;
new_nr_grant_frames = nr_grant_frames + more_frames;
extra_entries = more_frames * GREFS_PER_GRANT_FRAME;
for (i = nr_grant_frames; i < new_nr_grant_frames; i++)
{
gnttab_list[i] = (grant_ref_t *)
malloc(PAGE_SIZE, M_DEVBUF, M_NOWAIT);
if (!gnttab_list[i])
goto grow_nomem;
}
for (i = GREFS_PER_GRANT_FRAME * nr_grant_frames;
i < GREFS_PER_GRANT_FRAME * new_nr_grant_frames - 1; i++)
gnttab_entry(i) = i + 1;
gnttab_entry(i) = gnttab_free_head;
gnttab_free_head = GREFS_PER_GRANT_FRAME * nr_grant_frames;
gnttab_free_count += extra_entries;
nr_grant_frames = new_nr_grant_frames;
check_free_callbacks();
return (0);
grow_nomem:
for ( ; i >= nr_grant_frames; i--)
free(gnttab_list[i], M_DEVBUF);
return (ENOMEM);
}