[AF_PACKET]: Convert PACKET_MMAP over to vm_insert_page().
So we can properly use __GFP_COMP and avoid the use of
PG_reserved pages.
With extremely helpful review from Hugh Dickins.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 499ae3d..3e24627 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -1587,23 +1587,47 @@
return virt_to_page(one_pg_vec + (PAGE_SIZE << order) - 1);
}
-static void free_pg_vec(char **pg_vec, unsigned order, unsigned len)
+static void free_pg_vec(char **pg_vec, unsigned int order, unsigned int len)
{
int i;
- for (i=0; i<len; i++) {
- if (pg_vec[i]) {
- struct page *page, *pend;
-
- pend = pg_vec_endpage(pg_vec[i], order);
- for (page = virt_to_page(pg_vec[i]); page <= pend; page++)
- ClearPageReserved(page);
- free_pages((unsigned long)pg_vec[i], order);
- }
+ for (i = 0; i < len; i++) {
+ if (likely(pg_vec[i]))
+ free_pages((unsigned long) pg_vec[i], order);
}
kfree(pg_vec);
}
+static inline char *alloc_one_pg_vec_page(unsigned long order)
+{
+ return (char *) __get_free_pages(GFP_KERNEL | __GFP_COMP | __GFP_ZERO,
+ order);
+}
+
+static char **alloc_pg_vec(struct tpacket_req *req, int order)
+{
+ unsigned int block_nr = req->tp_block_nr;
+ char **pg_vec;
+ int i;
+
+ pg_vec = kzalloc(block_nr * sizeof(char *), GFP_KERNEL);
+ if (unlikely(!pg_vec))
+ goto out;
+
+ for (i = 0; i < block_nr; i++) {
+ pg_vec[i] = alloc_one_pg_vec_page(order);
+ if (unlikely(!pg_vec[i]))
+ goto out_free_pgvec;
+ }
+
+out:
+ return pg_vec;
+
+out_free_pgvec:
+ free_pg_vec(pg_vec, order, block_nr);
+ pg_vec = NULL;
+ goto out;
+}
static int packet_set_ring(struct sock *sk, struct tpacket_req *req, int closing)
{
@@ -1617,64 +1641,46 @@
/* Sanity tests and some calculations */
- if (po->pg_vec)
+ if (unlikely(po->pg_vec))
return -EBUSY;
- if ((int)req->tp_block_size <= 0)
+ if (unlikely((int)req->tp_block_size <= 0))
return -EINVAL;
- if (req->tp_block_size&(PAGE_SIZE-1))
+ if (unlikely(req->tp_block_size & (PAGE_SIZE - 1)))
return -EINVAL;
- if (req->tp_frame_size < TPACKET_HDRLEN)
+ if (unlikely(req->tp_frame_size < TPACKET_HDRLEN))
return -EINVAL;
- if (req->tp_frame_size&(TPACKET_ALIGNMENT-1))
+ if (unlikely(req->tp_frame_size & (TPACKET_ALIGNMENT - 1)))
return -EINVAL;
po->frames_per_block = req->tp_block_size/req->tp_frame_size;
- if (po->frames_per_block <= 0)
+ if (unlikely(po->frames_per_block <= 0))
return -EINVAL;
- if (po->frames_per_block*req->tp_block_nr != req->tp_frame_nr)
+ if (unlikely((po->frames_per_block * req->tp_block_nr) !=
+ req->tp_frame_nr))
return -EINVAL;
- /* OK! */
-
- /* Allocate page vector */
- while ((PAGE_SIZE<<order) < req->tp_block_size)
- order++;
err = -ENOMEM;
-
- pg_vec = kmalloc(req->tp_block_nr*sizeof(char *), GFP_KERNEL);
- if (pg_vec == NULL)
+ order = get_order(req->tp_block_size);
+ pg_vec = alloc_pg_vec(req, order);
+ if (unlikely(!pg_vec))
goto out;
- memset(pg_vec, 0, req->tp_block_nr*sizeof(char **));
-
- for (i=0; i<req->tp_block_nr; i++) {
- struct page *page, *pend;
- pg_vec[i] = (char *)__get_free_pages(GFP_KERNEL, order);
- if (!pg_vec[i])
- goto out_free_pgvec;
-
- pend = pg_vec_endpage(pg_vec[i], order);
- for (page = virt_to_page(pg_vec[i]); page <= pend; page++)
- SetPageReserved(page);
- }
- /* Page vector is allocated */
l = 0;
- for (i=0; i<req->tp_block_nr; i++) {
+ for (i = 0; i < req->tp_block_nr; i++) {
char *ptr = pg_vec[i];
struct tpacket_hdr *header;
int k;
- for (k=0; k<po->frames_per_block; k++) {
-
- header = (struct tpacket_hdr*)ptr;
+ for (k = 0; k < po->frames_per_block; k++) {
+ header = (struct tpacket_hdr *) ptr;
header->tp_status = TP_STATUS_KERNEL;
ptr += req->tp_frame_size;
}
}
/* Done */
} else {
- if (req->tp_frame_nr)
+ if (unlikely(req->tp_frame_nr))
return -EINVAL;
}
@@ -1701,7 +1707,7 @@
spin_lock_bh(&sk->sk_receive_queue.lock);
pg_vec = XC(po->pg_vec, pg_vec);
- po->frame_max = req->tp_frame_nr-1;
+ po->frame_max = (req->tp_frame_nr - 1);
po->head = 0;
po->frame_size = req->tp_frame_size;
spin_unlock_bh(&sk->sk_receive_queue.lock);
@@ -1728,7 +1734,6 @@
release_sock(sk);
-out_free_pgvec:
if (pg_vec)
free_pg_vec(pg_vec, order, req->tp_block_nr);
out:
@@ -1755,17 +1760,19 @@
if (size != po->pg_vec_len*po->pg_vec_pages*PAGE_SIZE)
goto out;
- atomic_inc(&po->mapped);
start = vma->vm_start;
- err = -EAGAIN;
- for (i=0; i<po->pg_vec_len; i++) {
- if (remap_pfn_range(vma, start,
- __pa(po->pg_vec[i]) >> PAGE_SHIFT,
- po->pg_vec_pages*PAGE_SIZE,
- vma->vm_page_prot))
- goto out;
- start += po->pg_vec_pages*PAGE_SIZE;
+ for (i = 0; i < po->pg_vec_len; i++) {
+ struct page *page = virt_to_page(po->pg_vec[i]);
+ int pg_num;
+
+ for (pg_num = 0; pg_num < po->pg_vec_pages; pg_num++, page++) {
+ err = vm_insert_page(vma, start, page);
+ if (unlikely(err))
+ goto out;
+ start += PAGE_SIZE;
+ }
}
+ atomic_inc(&po->mapped);
vma->vm_ops = &packet_mmap_ops;
err = 0;