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Diffstat (limited to 'drivers/block/xen-blkback/blkback.c')
-rw-r--r--drivers/block/xen-blkback/blkback.c89
1 files changed, 17 insertions, 72 deletions
diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c
index 501e9dacfff9..9ebf53903d7b 100644
--- a/drivers/block/xen-blkback/blkback.c
+++ b/drivers/block/xen-blkback/blkback.c
@@ -132,73 +132,12 @@ module_param(log_stats, int, 0644);
#define BLKBACK_INVALID_HANDLE (~0)
-/* Number of free pages to remove on each call to gnttab_free_pages */
-#define NUM_BATCH_FREE_PAGES 10
-
static inline bool persistent_gnt_timeout(struct persistent_gnt *persistent_gnt)
{
return pgrant_timeout && (jiffies - persistent_gnt->last_used >=
HZ * pgrant_timeout);
}
-static inline int get_free_page(struct xen_blkif_ring *ring, struct page **page)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&ring->free_pages_lock, flags);
- if (list_empty(&ring->free_pages)) {
- BUG_ON(ring->free_pages_num != 0);
- spin_unlock_irqrestore(&ring->free_pages_lock, flags);
- return gnttab_alloc_pages(1, page);
- }
- BUG_ON(ring->free_pages_num == 0);
- page[0] = list_first_entry(&ring->free_pages, struct page, lru);
- list_del(&page[0]->lru);
- ring->free_pages_num--;
- spin_unlock_irqrestore(&ring->free_pages_lock, flags);
-
- return 0;
-}
-
-static inline void put_free_pages(struct xen_blkif_ring *ring, struct page **page,
- int num)
-{
- unsigned long flags;
- int i;
-
- spin_lock_irqsave(&ring->free_pages_lock, flags);
- for (i = 0; i < num; i++)
- list_add(&page[i]->lru, &ring->free_pages);
- ring->free_pages_num += num;
- spin_unlock_irqrestore(&ring->free_pages_lock, flags);
-}
-
-static inline void shrink_free_pagepool(struct xen_blkif_ring *ring, int num)
-{
- /* Remove requested pages in batches of NUM_BATCH_FREE_PAGES */
- struct page *page[NUM_BATCH_FREE_PAGES];
- unsigned int num_pages = 0;
- unsigned long flags;
-
- spin_lock_irqsave(&ring->free_pages_lock, flags);
- while (ring->free_pages_num > num) {
- BUG_ON(list_empty(&ring->free_pages));
- page[num_pages] = list_first_entry(&ring->free_pages,
- struct page, lru);
- list_del(&page[num_pages]->lru);
- ring->free_pages_num--;
- if (++num_pages == NUM_BATCH_FREE_PAGES) {
- spin_unlock_irqrestore(&ring->free_pages_lock, flags);
- gnttab_free_pages(num_pages, page);
- spin_lock_irqsave(&ring->free_pages_lock, flags);
- num_pages = 0;
- }
- }
- spin_unlock_irqrestore(&ring->free_pages_lock, flags);
- if (num_pages != 0)
- gnttab_free_pages(num_pages, page);
-}
-
#define vaddr(page) ((unsigned long)pfn_to_kaddr(page_to_pfn(page)))
static int do_block_io_op(struct xen_blkif_ring *ring, unsigned int *eoi_flags);
@@ -331,7 +270,8 @@ static void free_persistent_gnts(struct xen_blkif_ring *ring, struct rb_root *ro
unmap_data.count = segs_to_unmap;
BUG_ON(gnttab_unmap_refs_sync(&unmap_data));
- put_free_pages(ring, pages, segs_to_unmap);
+ gnttab_page_cache_put(&ring->free_pages, pages,
+ segs_to_unmap);
segs_to_unmap = 0;
}
@@ -371,7 +311,8 @@ void xen_blkbk_unmap_purged_grants(struct work_struct *work)
if (++segs_to_unmap == BLKIF_MAX_SEGMENTS_PER_REQUEST) {
unmap_data.count = segs_to_unmap;
BUG_ON(gnttab_unmap_refs_sync(&unmap_data));
- put_free_pages(ring, pages, segs_to_unmap);
+ gnttab_page_cache_put(&ring->free_pages, pages,
+ segs_to_unmap);
segs_to_unmap = 0;
}
kfree(persistent_gnt);
@@ -379,7 +320,7 @@ void xen_blkbk_unmap_purged_grants(struct work_struct *work)
if (segs_to_unmap > 0) {
unmap_data.count = segs_to_unmap;
BUG_ON(gnttab_unmap_refs_sync(&unmap_data));
- put_free_pages(ring, pages, segs_to_unmap);
+ gnttab_page_cache_put(&ring->free_pages, pages, segs_to_unmap);
}
}
@@ -664,9 +605,10 @@ purge_gnt_list:
/* Shrink the free pages pool if it is too large. */
if (time_before(jiffies, blkif->buffer_squeeze_end))
- shrink_free_pagepool(ring, 0);
+ gnttab_page_cache_shrink(&ring->free_pages, 0);
else
- shrink_free_pagepool(ring, max_buffer_pages);
+ gnttab_page_cache_shrink(&ring->free_pages,
+ max_buffer_pages);
if (log_stats && time_after(jiffies, ring->st_print))
print_stats(ring);
@@ -697,7 +639,7 @@ void xen_blkbk_free_caches(struct xen_blkif_ring *ring)
ring->persistent_gnt_c = 0;
/* Since we are shutting down remove all pages from the buffer */
- shrink_free_pagepool(ring, 0 /* All */);
+ gnttab_page_cache_shrink(&ring->free_pages, 0 /* All */);
}
static unsigned int xen_blkbk_unmap_prepare(
@@ -736,7 +678,7 @@ static void xen_blkbk_unmap_and_respond_callback(int result, struct gntab_unmap_
but is this the best way to deal with this? */
BUG_ON(result);
- put_free_pages(ring, data->pages, data->count);
+ gnttab_page_cache_put(&ring->free_pages, data->pages, data->count);
make_response(ring, pending_req->id,
pending_req->operation, pending_req->status);
free_req(ring, pending_req);
@@ -803,7 +745,8 @@ static void xen_blkbk_unmap(struct xen_blkif_ring *ring,
if (invcount) {
ret = gnttab_unmap_refs(unmap, NULL, unmap_pages, invcount);
BUG_ON(ret);
- put_free_pages(ring, unmap_pages, invcount);
+ gnttab_page_cache_put(&ring->free_pages, unmap_pages,
+ invcount);
}
pages += batch;
num -= batch;
@@ -850,7 +793,8 @@ again:
pages[i]->page = persistent_gnt->page;
pages[i]->persistent_gnt = persistent_gnt;
} else {
- if (get_free_page(ring, &pages[i]->page))
+ if (gnttab_page_cache_get(&ring->free_pages,
+ &pages[i]->page))
goto out_of_memory;
addr = vaddr(pages[i]->page);
pages_to_gnt[segs_to_map] = pages[i]->page;
@@ -883,7 +827,8 @@ again:
BUG_ON(new_map_idx >= segs_to_map);
if (unlikely(map[new_map_idx].status != 0)) {
pr_debug("invalid buffer -- could not remap it\n");
- put_free_pages(ring, &pages[seg_idx]->page, 1);
+ gnttab_page_cache_put(&ring->free_pages,
+ &pages[seg_idx]->page, 1);
pages[seg_idx]->handle = BLKBACK_INVALID_HANDLE;
ret |= 1;
goto next;
@@ -944,7 +889,7 @@ next:
out_of_memory:
pr_alert("%s: out of memory\n", __func__);
- put_free_pages(ring, pages_to_gnt, segs_to_map);
+ gnttab_page_cache_put(&ring->free_pages, pages_to_gnt, segs_to_map);
for (i = last_map; i < num; i++)
pages[i]->handle = BLKBACK_INVALID_HANDLE;
return -ENOMEM;
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-19 19:17:30 +0000