[dm-devel] [RFC][PATCH 9/10] I/O context inheritance

[Hirokazu Takahashi]

The packet writing module creates a bio in its own way, so its iocontext
should be set here.

This code hasn't been tested yet.


Signed-off-by: Hirokazu Takahashi <taka at valinux.co.jp>


--- linux-2.6.25.bio0/drivers/block/pktcdvd.c	2008-04-22 15:48:36.000000000 +0900
+++ linux-2.6.25/drivers/block/pktcdvd.c	2008-04-22 15:53:41.000000000 +0900
@@ -514,6 +514,7 @@ static void pkt_bio_finished(struct pktc
 
 static void pkt_bio_destructor(struct bio *bio)
 {
+	put_io_context(bio->bi_io_context);
 	kfree(bio->bi_io_vec);
 	kfree(bio);
 }
@@ -522,6 +523,11 @@ static struct bio *pkt_bio_alloc(int nr_
 {
 	struct bio_vec *bvl = NULL;
 	struct bio *bio;
+	struct io_context *ioc;
+
+	ioc = get_io_context(GFP_KERNEL, -1);
+	if (!ioc)
+		goto no_ioc;
 
 	bio = kmalloc(sizeof(struct bio), GFP_KERNEL);
 	if (!bio)
@@ -535,12 +541,15 @@ static struct bio *pkt_bio_alloc(int nr_
 	bio->bi_max_vecs = nr_iovecs;
 	bio->bi_io_vec = bvl;
 	bio->bi_destructor = pkt_bio_destructor;
+	bio->bi_io_context = ioc;
 
 	return bio;
 
  no_bvl:
 	kfree(bio);
  no_bio:
+	put_io_context(ioc);
+ no_ioc:
 	return NULL;
 }