From: Jonathan Lallinger Date: Thu, 29 Sep 2011 07:58:41 +0000 (+0000) Subject: RDSRDMA: Fix cleanup of rds_iw_mr_pool X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=85a64889492b45f931ddac87ec09d84aa7347ee1;p=linux-beck.git RDSRDMA: Fix cleanup of rds_iw_mr_pool In the rds_iw_mr_pool struct the free_pinned field keeps track of memory pinned by free MRs. While this field is incremented properly upon allocation, it is never decremented upon unmapping. This would cause the rds_rdma module to crash the kernel upon unloading, by triggering the BUG_ON in the rds_iw_destroy_mr_pool function. This change keeps track of the MRs that become unpinned, so that free_pinned can be decremented appropriately. Signed-off-by: Jonathan Lallinger Signed-off-by: Steve Wise Signed-off-by: David S. Miller --- diff --git a/net/rds/iw_rdma.c b/net/rds/iw_rdma.c index 8b77edbab272..4e1de171866c 100644 --- a/net/rds/iw_rdma.c +++ b/net/rds/iw_rdma.c @@ -84,7 +84,8 @@ static int rds_iw_map_fastreg(struct rds_iw_mr_pool *pool, static void rds_iw_free_fastreg(struct rds_iw_mr_pool *pool, struct rds_iw_mr *ibmr); static unsigned int rds_iw_unmap_fastreg_list(struct rds_iw_mr_pool *pool, struct list_head *unmap_list, - struct list_head *kill_list); + struct list_head *kill_list, + int *unpinned); static void rds_iw_destroy_fastreg(struct rds_iw_mr_pool *pool, struct rds_iw_mr *ibmr); static int rds_iw_get_device(struct rds_sock *rs, struct rds_iw_device **rds_iwdev, struct rdma_cm_id **cm_id) @@ -499,7 +500,7 @@ static int rds_iw_flush_mr_pool(struct rds_iw_mr_pool *pool, int free_all) LIST_HEAD(unmap_list); LIST_HEAD(kill_list); unsigned long flags; - unsigned int nfreed = 0, ncleaned = 0, free_goal; + unsigned int nfreed = 0, ncleaned = 0, unpinned = 0, free_goal; int ret = 0; rds_iw_stats_inc(s_iw_rdma_mr_pool_flush); @@ -524,7 +525,8 @@ static int rds_iw_flush_mr_pool(struct rds_iw_mr_pool *pool, int free_all) * will be destroyed by the unmap function. */ if (!list_empty(&unmap_list)) { - ncleaned = rds_iw_unmap_fastreg_list(pool, &unmap_list, &kill_list); + ncleaned = rds_iw_unmap_fastreg_list(pool, &unmap_list, + &kill_list, &unpinned); /* If we've been asked to destroy all MRs, move those * that were simply cleaned to the kill list */ if (free_all) @@ -548,6 +550,7 @@ static int rds_iw_flush_mr_pool(struct rds_iw_mr_pool *pool, int free_all) spin_unlock_irqrestore(&pool->list_lock, flags); } + atomic_sub(unpinned, &pool->free_pinned); atomic_sub(ncleaned, &pool->dirty_count); atomic_sub(nfreed, &pool->item_count); @@ -828,7 +831,8 @@ static void rds_iw_free_fastreg(struct rds_iw_mr_pool *pool, static unsigned int rds_iw_unmap_fastreg_list(struct rds_iw_mr_pool *pool, struct list_head *unmap_list, - struct list_head *kill_list) + struct list_head *kill_list, + int *unpinned) { struct rds_iw_mapping *mapping, *next; unsigned int ncleaned = 0; @@ -855,6 +859,7 @@ static unsigned int rds_iw_unmap_fastreg_list(struct rds_iw_mr_pool *pool, spin_lock_irqsave(&pool->list_lock, flags); list_for_each_entry_safe(mapping, next, unmap_list, m_list) { + *unpinned += mapping->m_sg.len; list_move(&mapping->m_list, &laundered); ncleaned++; }