From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr1-f65.google.com ([209.85.221.65]:45670 "EHLO mail-wr1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390076AbeIVAKt (ORCPT ); Fri, 21 Sep 2018 20:10:49 -0400 From: Amir Goldstein To: Jan Kara Cc: nixiaoming@huawei.com, linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.org Subject: [PATCH v2 2/2] fanotify: support reporting thread id instead of process id Date: Fri, 21 Sep 2018 21:20:31 +0300 Message-Id: <20180921182031.3184-3-amir73il@gmail.com> In-Reply-To: <20180921182031.3184-1-amir73il@gmail.com> References: <20180921182031.3184-1-amir73il@gmail.com> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: From: nixiaoming In order to identify which thread triggered the event in a multi-threaded program, add the FAN_EVENT_INFO_TID flag in fanotify_init to opt-in for reporting the event creator's thread id information. Signed-off-by: nixiaoming Signed-off-by: Amir Goldstein --- fs/notify/fanotify/fanotify.c | 9 ++++++--- fs/notify/fanotify/fanotify.h | 2 +- fs/notify/fanotify/fanotify_user.c | 2 +- include/uapi/linux/fanotify.h | 9 +++++++-- 4 files changed, 15 insertions(+), 7 deletions(-) diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c index 94b52157bf8d..e380027e545c 100644 --- a/fs/notify/fanotify/fanotify.c +++ b/fs/notify/fanotify/fanotify.c @@ -25,7 +25,7 @@ static bool should_merge(struct fsnotify_event *old_fsn, old = FANOTIFY_E(old_fsn); new = FANOTIFY_E(new_fsn); - if (old_fsn->inode == new_fsn->inode && old->tgid == new->tgid && + if (old_fsn->inode == new_fsn->inode && old->pid == new->pid && old->path.mnt == new->path.mnt && old->path.dentry == new->path.dentry) return true; @@ -171,7 +171,10 @@ struct fanotify_event_info *fanotify_alloc_event(struct fsnotify_group *group, goto out; init: __maybe_unused fsnotify_init_event(&event->fse, inode, mask); - event->tgid = get_pid(task_tgid(current)); + if (FAN_GROUP_FLAG(group, FAN_EVENT_INFO_TID)) + event->pid = get_pid(task_pid(current)); + else + event->pid = get_pid(task_tgid(current)); if (path) { event->path = *path; path_get(&event->path); @@ -268,7 +271,7 @@ static void fanotify_free_event(struct fsnotify_event *fsn_event) event = FANOTIFY_E(fsn_event); path_put(&event->path); - put_pid(event->tgid); + put_pid(event->pid); if (fanotify_is_perm_event(fsn_event->mask)) { kmem_cache_free(fanotify_perm_event_cachep, FANOTIFY_PE(fsn_event)); diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h index 8609ba06f474..d8d85104e7ff 100644 --- a/fs/notify/fanotify/fanotify.h +++ b/fs/notify/fanotify/fanotify.h @@ -19,7 +19,7 @@ struct fanotify_event_info { * during this object's lifetime */ struct path path; - struct pid *tgid; + struct pid *pid; }; /* diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c index 15719d4aa4b5..039d31ea4380 100644 --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -132,7 +132,7 @@ static int fill_event_metadata(struct fsnotify_group *group, metadata->vers = FANOTIFY_METADATA_VERSION; metadata->reserved = 0; metadata->mask = fsn_event->mask & FAN_ALL_OUTGOING_EVENTS; - metadata->pid = pid_vnr(event->tgid); + metadata->pid = pid_vnr(event->pid); if (unlikely(fsn_event->mask & FAN_Q_OVERFLOW)) metadata->fd = FAN_NOFD; else { diff --git a/include/uapi/linux/fanotify.h b/include/uapi/linux/fanotify.h index ad81234d1919..6d98d14a6314 100644 --- a/include/uapi/linux/fanotify.h +++ b/include/uapi/linux/fanotify.h @@ -38,9 +38,14 @@ #define FAN_UNLIMITED_MARKS 0x00000020 #define FAN_ENABLE_AUDIT 0x00000040 +/* Flags to determine fanotify event format */ +#define FAN_EVENT_INFO_TID 0x00000100 /* event->pid is thread id */ + +#define FAN_EVENT_INFO_FLAGS (FAN_EVENT_INFO_TID) + #define FAN_ALL_INIT_FLAGS (FAN_CLOEXEC | FAN_NONBLOCK | \ - FAN_ALL_CLASS_BITS | FAN_UNLIMITED_QUEUE |\ - FAN_UNLIMITED_MARKS) + FAN_ALL_CLASS_BITS | FAN_EVENT_INFO_FLAGS | \ + FAN_UNLIMITED_QUEUE | FAN_UNLIMITED_MARKS) /* flags used for fanotify_modify_mark() */ #define FAN_MARK_ADD 0x00000001 -- 2.17.1