Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756182AbdLOKUC (ORCPT ); Fri, 15 Dec 2017 05:20:02 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:35514 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755039AbdLOJu3 (ORCPT ); Fri, 15 Dec 2017 04:50:29 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Stephen Bates , Logan Gunthorpe , Mathieu Desnoyers , Daniel Mentz , Jonathan Corbet , Andrew Morton , Will Deacon , Linus Torvalds , Sasha Levin Subject: [PATCH 4.4 077/105] lib/genalloc.c: make the avail variable an atomic_long_t Date: Fri, 15 Dec 2017 10:45:15 +0100 Message-Id: <20171215092309.889323597@linuxfoundation.org> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20171215092305.994559179@linuxfoundation.org> References: <20171215092305.994559179@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3425 Lines: 102 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Stephen Bates [ Upstream commit 36a3d1dd4e16bcd0d2ddfb4a2ec7092f0ae0d931 ] If the amount of resources allocated to a gen_pool exceeds 2^32 then the avail atomic overflows and this causes problems when clients try and borrow resources from the pool. This is only expected to be an issue on 64 bit systems. Add the header to pull in atomic_long* operations. So that 32 bit systems continue to use atomic32_t but 64 bit systems can use atomic64_t. Link: http://lkml.kernel.org/r/1509033843-25667-1-git-send-email-sbates@raithlin.com Signed-off-by: Stephen Bates Reviewed-by: Logan Gunthorpe Reviewed-by: Mathieu Desnoyers Reviewed-by: Daniel Mentz Cc: Jonathan Corbet Cc: Andrew Morton Cc: Will Deacon Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- include/linux/genalloc.h | 3 ++- lib/genalloc.c | 10 +++++----- 2 files changed, 7 insertions(+), 6 deletions(-) --- a/include/linux/genalloc.h +++ b/include/linux/genalloc.h @@ -31,6 +31,7 @@ #define __GENALLOC_H__ #include +#include struct device; struct device_node; @@ -68,7 +69,7 @@ struct gen_pool { */ struct gen_pool_chunk { struct list_head next_chunk; /* next chunk in pool */ - atomic_t avail; + atomic_long_t avail; phys_addr_t phys_addr; /* physical starting address of memory chunk */ unsigned long start_addr; /* start address of memory chunk */ unsigned long end_addr; /* end address of memory chunk (inclusive) */ --- a/lib/genalloc.c +++ b/lib/genalloc.c @@ -194,7 +194,7 @@ int gen_pool_add_virt(struct gen_pool *p chunk->phys_addr = phys; chunk->start_addr = virt; chunk->end_addr = virt + size - 1; - atomic_set(&chunk->avail, size); + atomic_long_set(&chunk->avail, size); spin_lock(&pool->lock); list_add_rcu(&chunk->next_chunk, &pool->chunks); @@ -285,7 +285,7 @@ unsigned long gen_pool_alloc(struct gen_ nbits = (size + (1UL << order) - 1) >> order; rcu_read_lock(); list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk) { - if (size > atomic_read(&chunk->avail)) + if (size > atomic_long_read(&chunk->avail)) continue; start_bit = 0; @@ -305,7 +305,7 @@ retry: addr = chunk->start_addr + ((unsigned long)start_bit << order); size = nbits << order; - atomic_sub(size, &chunk->avail); + atomic_long_sub(size, &chunk->avail); break; } rcu_read_unlock(); @@ -371,7 +371,7 @@ void gen_pool_free(struct gen_pool *pool remain = bitmap_clear_ll(chunk->bits, start_bit, nbits); BUG_ON(remain); size = nbits << order; - atomic_add(size, &chunk->avail); + atomic_long_add(size, &chunk->avail); rcu_read_unlock(); return; } @@ -445,7 +445,7 @@ size_t gen_pool_avail(struct gen_pool *p rcu_read_lock(); list_for_each_entry_rcu(chunk, &pool->chunks, next_chunk) - avail += atomic_read(&chunk->avail); + avail += atomic_long_read(&chunk->avail); rcu_read_unlock(); return avail; }