From 84c9618190f9e3a526ce51dc4995fcfa3a9ed265 Mon Sep 17 00:00:00 2001 From: Bobi Jam Date: Tue, 3 Jan 2023 13:57:24 +0800 Subject: [PATCH] LU-16160 revert: "llite: clear stale page's uptodate bit" This reverts commit 5b911e03261c3de6b0c2934c86dd191f01af4f2f which caused a bug in cl_page_own() race with ll_releasepage() and cl_pagevec_put() assertion failure. Signed-off-by: Bobi Jam Change-Id: Icdb8c60f4d992c9976670e1b06c5bab5ef3a3954 Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/49541 Reviewed-by: Oleg Drokin Reviewed-by: Andreas Dilger Reviewed-by: Qian Yingjin Tested-by: jenkins Tested-by: Maloo --- lustre/include/cl_object.h | 15 +----- lustre/llite/rw.c | 10 +--- lustre/llite/vvp_io.c | 118 +++------------------------------------------ lustre/obdclass/cl_page.c | 38 ++++----------- lustre/tests/sanityn.sh | 4 +- 5 files changed, 22 insertions(+), 163 deletions(-) diff --git a/lustre/include/cl_object.h b/lustre/include/cl_object.h index 3daeefa..5449cef 100644 --- a/lustre/include/cl_object.h +++ b/lustre/include/cl_object.h @@ -767,15 +767,7 @@ struct cl_page { enum cl_page_type cp_type:CP_TYPE_BITS; unsigned cp_defer_uptodate:1, cp_ra_updated:1, - cp_ra_used:1, - /* fault page read grab extra referece */ - cp_fault_ref:1, - /** - * if fault page got delete before returned to - * filemap_fault(), defer the vmpage detach/put - * until filemap_fault() has been handled. - */ - cp_defer_detach:1; + cp_ra_used:1; /* which slab kmem index this memory allocated from */ short int cp_kmem_index; @@ -2397,11 +2389,6 @@ static inline int cl_io_is_mkwrite(const struct cl_io *io) return io->ci_type == CIT_FAULT && io->u.ci_fault.ft_mkwrite; } -static inline int cl_io_is_pagefault(const struct cl_io *io) -{ - return io->ci_type == CIT_FAULT && !io->u.ci_fault.ft_mkwrite; -} - /** * True, iff \a io is a truncate(2). */ diff --git a/lustre/llite/rw.c b/lustre/llite/rw.c index 0f76a88..66496e6 100644 --- a/lustre/llite/rw.c +++ b/lustre/llite/rw.c @@ -1943,15 +1943,7 @@ int ll_readpage(struct file *file, struct page *vmpage) unlock_page(vmpage); result = 0; } - if (cl_io_is_pagefault(io) && result == 0) { - /** - * page fault, retain the cl_page reference until - * vvp_io_kernel_fault() release it. - */ - page->cp_fault_ref = 1; - } else { - cl_page_put(env, page); - } + cl_page_put(env, page); } else { unlock_page(vmpage); result = PTR_ERR(page); diff --git a/lustre/llite/vvp_io.c b/lustre/llite/vvp_io.c index 3c500a5..f1cb18d 100644 --- a/lustre/llite/vvp_io.c +++ b/lustre/llite/vvp_io.c @@ -1391,37 +1391,10 @@ static void vvp_io_rw_end(const struct lu_env *env, trunc_sem_up_read(&lli->lli_trunc_sem); } -static void detach_and_deref_page(struct cl_page *clp, struct page *vmpage) -{ - if (!clp->cp_defer_detach) - return; - - /** - * cl_page_delete0() took a vmpage reference, but not unlink the vmpage - * from its cl_page. - */ - clp->cp_defer_detach = 0; - ClearPagePrivate(vmpage); - vmpage->private = 0; - - put_page(vmpage); - refcount_dec(&clp->cp_ref); -} - -static int vvp_io_kernel_fault(const struct lu_env *env, - struct vvp_fault_io *cfio) +static int vvp_io_kernel_fault(struct vvp_fault_io *cfio) { struct vm_fault *vmf = cfio->ft_vmf; - struct file *vmff = cfio->ft_vma->vm_file; - struct address_space *mapping = vmff->f_mapping; - struct inode *inode = mapping->host; - struct page *vmpage = NULL; - struct cl_page *clp = NULL; - int rc = 0; - ENTRY; - ll_inode_size_lock(inode); -retry: cfio->ft_flags = ll_filemap_fault(cfio->ft_vma, vmf); cfio->ft_flags_valid = 1; @@ -1436,100 +1409,25 @@ retry: cfio->ft_vmpage = vmf->page; - /** - * ll_filemap_fault()->ll_readpage() could get an extra cl_page - * reference. So we have to get the cl_page's to check its - * cp_fault_ref and drop the reference later. - */ - clp = cl_vmpage_page(vmf->page, NULL); - - GOTO(unlock, rc = 0); - } - - /* filemap_fault() fails, vmpage is not locked */ - if (clp == NULL) { - vmpage = find_get_page(mapping, vmf->pgoff); - if (vmpage) { - lock_page(vmpage); - clp = cl_vmpage_page(vmpage, NULL); - unlock_page(vmpage); - } + return 0; } if (cfio->ft_flags & VM_FAULT_SIGBUS) { - pgoff_t max_idx; - - /** - * ll_filemap_fault()->ll_readpage() could fill vmpage - * correctly, and unlock the vmpage, while memory pressure or - * truncate could detach cl_page from vmpage, and kernel - * filemap_fault() will wait_on_page_locked(vmpage) and find - * out that the vmpage has been cleared its uptodate bit, - * so it returns VM_FAULT_SIGBUS. - * - * In this case, we'd retry the filemap_fault()->ll_readpage() - * to rebuild the cl_page and fill vmpage with uptodated data. - */ - if (likely(vmpage)) { - bool need_retry = false; - - if (clp) { - if (clp->cp_defer_detach) { - detach_and_deref_page(clp, vmpage); - /** - * check i_size to make sure it's not - * over EOF, we don't want to call - * filemap_fault() repeatedly since it - * returns VM_FAULT_SIGBUS without even - * trying if vmf->pgoff is over EOF. - */ - max_idx = DIV_ROUND_UP( - i_size_read(inode), PAGE_SIZE); - if (vmf->pgoff < max_idx) - need_retry = true; - } - if (clp->cp_fault_ref) { - clp->cp_fault_ref = 0; - /* ref not released in ll_readpage() */ - cl_page_put(env, clp); - } - if (need_retry) - goto retry; - } - } - CDEBUG(D_PAGE, "got addr %p - SIGBUS\n", get_vmf_address(vmf)); - GOTO(unlock, rc = -EFAULT); + return -EFAULT; } if (cfio->ft_flags & VM_FAULT_OOM) { CDEBUG(D_PAGE, "got addr %p - OOM\n", get_vmf_address(vmf)); - GOTO(unlock, rc = -ENOMEM); + return -ENOMEM; } if (cfio->ft_flags & VM_FAULT_RETRY) - GOTO(unlock, rc = -EAGAIN); + return -EAGAIN; CERROR("unknown error in page fault %d\n", cfio->ft_flags); - rc = -EINVAL; -unlock: - ll_inode_size_unlock(inode); - if (clp) { - if (clp->cp_defer_detach && vmpage) - detach_and_deref_page(clp, vmpage); - - /* additional cl_page ref has been taken in ll_readpage() */ - if (clp->cp_fault_ref) { - clp->cp_fault_ref = 0; - /* ref not released in ll_readpage() */ - cl_page_put(env, clp); - } - /* ref taken in this function */ - cl_page_put(env, clp); - } - if (vmpage) - put_page(vmpage); - return rc; + + return -EINVAL; } static void mkwrite_commit_callback(const struct lu_env *env, struct cl_io *io, @@ -1570,7 +1468,7 @@ static int vvp_io_fault_start(const struct lu_env *env, LASSERT(cfio->ft_vmpage != NULL); lock_page(cfio->ft_vmpage); } else { - result = vvp_io_kernel_fault(env, cfio); + result = vvp_io_kernel_fault(cfio); if (result != 0) RETURN(result); } diff --git a/lustre/obdclass/cl_page.c b/lustre/obdclass/cl_page.c index bc384be..92ba1d6 100644 --- a/lustre/obdclass/cl_page.c +++ b/lustre/obdclass/cl_page.c @@ -827,35 +827,17 @@ static void __cl_page_delete(const struct lu_env *env, struct cl_page *cp) LASSERT(PageLocked(vmpage)); LASSERT((struct cl_page *)vmpage->private == cp); - /** - * clear vmpage uptodate bit, since ll_read_ahead_pages()-> - * ll_read_ahead_page() could pick up this stale vmpage and - * take it as uptodated. - */ - ClearPageUptodate(vmpage); - /** - * vvp_io_kernel_fault()->ll_readpage() set cp_fault_ref - * and need it to check cl_page to retry the page fault read. + /* Drop the reference count held in vvp_page_init */ + refcount_dec(&cp->cp_ref); + + ClearPagePrivate(vmpage); + vmpage->private = 0; + + /* + * The reference from vmpage to cl_page is removed, + * but the reference back is still here. It is removed + * later in cl_page_free(). */ - if (cp->cp_fault_ref) { - cp->cp_defer_detach = 1; - /** - * get a vmpage reference, so that filemap_fault() - * won't free it from pagecache. - */ - get_page(vmpage); - } else { - /* Drop the reference count held in vvp_page_init */ - refcount_dec(&cp->cp_ref); - ClearPagePrivate(vmpage); - vmpage->private = 0; - - /* - * The reference from vmpage to cl_page is removed, - * but the reference back is still here. It is removed - * later in cl_page_free(). - */ - } } EXIT; diff --git a/lustre/tests/sanityn.sh b/lustre/tests/sanityn.sh index ce4968e..8019af2 100755 --- a/lustre/tests/sanityn.sh +++ b/lustre/tests/sanityn.sh @@ -18,8 +18,8 @@ init_test_env $@ init_logging ALWAYS_EXCEPT="$SANITYN_EXCEPT " -# bug number for skipped test: LU-7105 -ALWAYS_EXCEPT+=" 28 " +# bug number for skipped test: LU-7105 LU-14541 LU-16160 +ALWAYS_EXCEPT+=" 28 16f 16g " # UPDATE THE COMMENT ABOVE WITH BUG NUMBERS WHEN CHANGING ALWAYS_EXCEPT! if [ $mds1_FSTYPE = "zfs" ]; then -- 1.8.3.1