From ff5d913dfc7142974eb1694d5fd6284658e46bc6 Mon Sep 17 00:00:00 2001 From: "Yan, Zheng" Date: Thu, 25 Jul 2019 20:16:45 +0800 Subject: [PATCH] ceph: return -EIO if read/write against filp that lost file locks After mds evicts session, file locks get lost sliently. It's not safe to let programs continue to do read/write. Signed-off-by: "Yan, Zheng" Reviewed-by: Jeff Layton Signed-off-by: Ilya Dryomov --- fs/ceph/caps.c | 28 ++++++++++++++++++++++------ fs/ceph/locks.c | 8 ++++++-- fs/ceph/super.h | 1 + 3 files changed, 29 insertions(+), 8 deletions(-) diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c index bde81aaa3750..102192c90edd 100644 --- a/fs/ceph/caps.c +++ b/fs/ceph/caps.c @@ -2570,8 +2570,13 @@ static void __take_cap_refs(struct ceph_inode_info *ci, int got, * * FIXME: how does a 0 return differ from -EAGAIN? */ +enum { + NON_BLOCKING = 1, + CHECK_FILELOCK = 2, +}; + static int try_get_cap_refs(struct inode *inode, int need, int want, - loff_t endoff, bool nonblock, int *got) + loff_t endoff, int flags, int *got) { struct ceph_inode_info *ci = ceph_inode(inode); struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc; @@ -2586,6 +2591,13 @@ static int try_get_cap_refs(struct inode *inode, int need, int want, again: spin_lock(&ci->i_ceph_lock); + if ((flags & CHECK_FILELOCK) && + (ci->i_ceph_flags & CEPH_I_ERROR_FILELOCK)) { + dout("try_get_cap_refs %p error filelock\n", inode); + ret = -EIO; + goto out_unlock; + } + /* make sure file is actually open */ file_wanted = __ceph_caps_file_wanted(ci); if ((file_wanted & need) != need) { @@ -2647,7 +2659,7 @@ again: * we can not call down_read() when * task isn't in TASK_RUNNING state */ - if (nonblock) { + if (flags & NON_BLOCKING) { ret = -EAGAIN; goto out_unlock; } @@ -2752,7 +2764,8 @@ int ceph_try_get_caps(struct inode *inode, int need, int want, if (ret < 0) return ret; - ret = try_get_cap_refs(inode, need, want, 0, nonblock, got); + ret = try_get_cap_refs(inode, need, want, 0, + (nonblock ? NON_BLOCKING : 0), got); return ret == -EAGAIN ? 0 : ret; } @@ -2764,9 +2777,10 @@ int ceph_try_get_caps(struct inode *inode, int need, int want, int ceph_get_caps(struct file *filp, int need, int want, loff_t endoff, int *got, struct page **pinned_page) { + struct ceph_file_info *fi = filp->private_data; struct inode *inode = file_inode(filp); struct ceph_inode_info *ci = ceph_inode(inode); - int _got, ret; + int ret, _got, flags; ret = ceph_pool_perm_check(inode, need); if (ret < 0) @@ -2776,17 +2790,19 @@ int ceph_get_caps(struct file *filp, int need, int want, if (endoff > 0) check_max_size(inode, endoff); + flags = atomic_read(&fi->num_locks) ? CHECK_FILELOCK : 0; _got = 0; ret = try_get_cap_refs(inode, need, want, endoff, - false, &_got); + flags, &_got); if (ret == -EAGAIN) continue; if (!ret) { DEFINE_WAIT_FUNC(wait, woken_wake_function); add_wait_queue(&ci->i_cap_wq, &wait); + flags |= NON_BLOCKING; while (!(ret = try_get_cap_refs(inode, need, want, - endoff, true, &_got))) { + endoff, flags, &_got))) { if (signal_pending(current)) { ret = -ERESTARTSYS; break; diff --git a/fs/ceph/locks.c b/fs/ceph/locks.c index 5083e238ad15..544e9e85b120 100644 --- a/fs/ceph/locks.c +++ b/fs/ceph/locks.c @@ -32,14 +32,18 @@ void __init ceph_flock_init(void) static void ceph_fl_copy_lock(struct file_lock *dst, struct file_lock *src) { - struct inode *inode = file_inode(src->fl_file); + struct ceph_file_info *fi = dst->fl_file->private_data; + struct inode *inode = file_inode(dst->fl_file); atomic_inc(&ceph_inode(inode)->i_filelock_ref); + atomic_inc(&fi->num_locks); } static void ceph_fl_release_lock(struct file_lock *fl) { + struct ceph_file_info *fi = fl->fl_file->private_data; struct inode *inode = file_inode(fl->fl_file); struct ceph_inode_info *ci = ceph_inode(inode); + atomic_dec(&fi->num_locks); if (atomic_dec_and_test(&ci->i_filelock_ref)) { /* clear error when all locks are released */ spin_lock(&ci->i_ceph_lock); @@ -73,7 +77,7 @@ static int ceph_lock_message(u8 lock_type, u16 operation, struct inode *inode, * window. Caller function will decrease the counter. */ fl->fl_ops = &ceph_fl_lock_ops; - atomic_inc(&ceph_inode(inode)->i_filelock_ref); + fl->fl_ops->fl_copy_lock(fl, NULL); } if (operation != CEPH_MDS_OP_SETFILELOCK || cmd == CEPH_LOCK_UNLOCK) diff --git a/fs/ceph/super.h b/fs/ceph/super.h index 7af7f2ba8da5..736318210bc9 100644 --- a/fs/ceph/super.h +++ b/fs/ceph/super.h @@ -707,6 +707,7 @@ struct ceph_file_info { struct list_head rw_contexts; errseq_t meta_err; + atomic_t num_locks; }; struct ceph_dir_file_info { -- 2.30.2