From mboxrd@z Thu Jan 1 00:00:00 1970 From: Oren Laadan Subject: [PATCH v18 12/80] pids 2/7: Have alloc_pidmap() return actual error code Date: Wed, 23 Sep 2009 19:50:52 -0400 Message-ID: <1253749920-18673-13-git-send-email-orenl__9741.86259923062$1253750661$gmane$org@librato.com> References: <1253749920-18673-1-git-send-email-orenl@librato.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1253749920-18673-1-git-send-email-orenl-RdfvBDnrOixBDgjK7y7TUQ@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Andrew Morton Cc: linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, Linus Torvalds , Ingo Molnar , Sukadev Bhattiprolu , Pavel Emelyanov List-Id: containers.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. Signed-off-by: Sukadev Bhattiprolu Acked-by: Serge Hallyn Reviewed-by: Oren Laadan --- kernel/fork.c | 5 +++-- kernel/pid.c | 9 ++++++--- 2 files changed, 9 insertions(+), 5 deletions(-) diff --git a/kernel/fork.c b/kernel/fork.c index e6c04d4..851ccd1 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1110,10 +1110,11 @@ 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 f618096..9c678ce 100644 --- a/kernel/pid.c +++ b/kernel/pid.c @@ -158,6 +158,7 @@ static int alloc_pidmap(struct pid_namespace *pid_ns) offset = pid & BITS_PER_PAGE_MASK; map = &pid_ns->pidmap[pid/BITS_PER_PAGE]; max_scan = (pid_max + BITS_PER_PAGE - 1)/BITS_PER_PAGE - !offset; + rc = -EAGAIN; for (i = 0; i <= max_scan; ++i) { rc = alloc_pidmap_page(map); if (rc) @@ -188,12 +189,14 @@ static int alloc_pidmap(struct pid_namespace *pid_ns) } else { map = &pid_ns->pidmap[0]; offset = RESERVED_PIDS; - if (unlikely(last == offset)) + if (unlikely(last == offset)) { + rc = -EAGAIN; break; + } } pid = mk_pid(pid_ns, map, offset); } - return -1; + return rc; } int next_pidmap(struct pid_namespace *pid_ns, int last) @@ -298,7 +301,7 @@ out_free: free_pidmap(pid->numbers + i); kmem_cache_free(ns->pid_cachep, pid); - pid = NULL; + pid = ERR_PTR(nr); goto out; } -- 1.6.0.4