From mboxrd@z Thu Jan 1 00:00:00 1970 From: Oren Laadan Subject: [PATCH v21 002/100] eclone (2/11): Have alloc_pidmap() return actual error code Date: Sat, 1 May 2010 10:14:44 -0400 Message-ID: <1272723382-19470-3-git-send-email-orenl@cs.columbia.edu> References: <1272723382-19470-1-git-send-email-orenl@cs.columbia.edu> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1272723382-19470-1-git-send-email-orenl@cs.columbia.edu> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linuxppc-dev-bounces+glppe-linuxppc-embedded-2=m.gmane.org@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+glppe-linuxppc-embedded-2=m.gmane.org@lists.ozlabs.org To: Andrew Morton Cc: linux-s390@vger.kernel.org, linux-api@vger.kernel.org, containers@lists.linux-foundation.org, x86@kernel.org, linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, Matt Helsley , Serge Hallyn , Sukadev Bhattiprolu , Pavel Emelyanov List-Id: linux-api@vger.kernel.org From: Sukadev Bhattiprolu alloc_pidmap() can fail either because all pid numbers are in use or because memory allocation failed. With support for setting a specific pid number, alloc_pidmap() would also fail if either the given pid number is invalid or in use. Rather than have callers assume -ENOMEM, have alloc_pidmap() return the actual error. Changelog[v1]: - [Oren Laadan] Rebase to kernel 2.6.33 Cc: linux-api@vger.kernel.org Cc: x86@kernel.org Cc: linux-s390@vger.kernel.org Cc: linuxppc-dev@ozlabs.org Signed-off-by: Sukadev Bhattiprolu Acked-by: Serge E. Hallyn Tested-by: Serge E. Hallyn Reviewed-by: Oren Laadan --- kernel/fork.c | 5 +++-- kernel/pid.c | 10 ++++++---- 2 files changed, 9 insertions(+), 6 deletions(-) diff --git a/kernel/fork.c b/kernel/fork.c index 44b0791..afdfb08 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1147,10 +1147,11 @@ static struct task_struct *copy_process(unsigned long clone_flags, goto bad_fork_cleanup_io; if (pid != &init_struct_pid) { - retval = -ENOMEM; pid = alloc_pid(p->nsproxy->pid_ns); - if (!pid) + if (IS_ERR(pid)) { + retval = PTR_ERR(pid); goto bad_fork_cleanup_io; + } if (clone_flags & CLONE_NEWPID) { retval = pid_ns_prepare_proc(p->nsproxy->pid_ns); diff --git a/kernel/pid.c b/kernel/pid.c index 52a371a..8330488 100644 --- a/kernel/pid.c +++ b/kernel/pid.c @@ -160,7 +160,7 @@ static int alloc_pidmap(struct pid_namespace *pid_ns) for (i = 0; i <= max_scan; ++i) { if (unlikely(!map->page)) if (alloc_pidmap_page(map) < 0) - break; + return -ENOMEM; if (likely(atomic_read(&map->nr_free))) { do { if (!test_and_set_bit(offset, map->page)) { @@ -191,7 +191,7 @@ static int alloc_pidmap(struct pid_namespace *pid_ns) } pid = mk_pid(pid_ns, map, offset); } - return -1; + return -EBUSY; } int next_pidmap(struct pid_namespace *pid_ns, int last) @@ -260,8 +260,10 @@ struct pid *alloc_pid(struct pid_namespace *ns) struct upid *upid; pid = kmem_cache_alloc(ns->pid_cachep, GFP_KERNEL); - if (!pid) + if (!pid) { + pid = ERR_PTR(-ENOMEM); goto out; + } tmp = ns; for (i = ns->level; i >= 0; i--) { @@ -295,7 +297,7 @@ out_free: free_pidmap(pid->numbers + i); kmem_cache_free(ns->pid_cachep, pid); - pid = NULL; + pid = ERR_PTR(nr); goto out; } -- 1.6.3.3