From b00795833c479bc90e524f3d1469ef61eede550e Mon Sep 17 00:00:00 2001 From: alc Date: Sat, 14 Jan 2012 23:04:27 +0000 Subject: [PATCH 159/175] Neither tmpfs_nocacheread() nor tmpfs_mappedwrite() needs to call vm_object_pip_{add,subtract}() on the swap object because the swap object can't be destroyed while the vnode is exclusively locked. Moreover, even if the swap object could have been destroyed during tmpfs_nocacheread() and tmpfs_mappedwrite() this code is broken because vm_object_pip_subtract() does not wake up the sleeping thread that is trying to destroy the swap object. Free invalid pages after an I/O error. There is no virtue in keeping them around in the swap object creating more work for the page daemon. (I believe that any non-busy page in the swap object will now always be valid.) vm_pager_get_pages() does not return a standard errno, so its return value should not be returned by tmpfs without translation to an errno value. There is no reason for the wakeup on vpg in tmpfs_mappedwrite() to occur with the swap object locked. Eliminate printf()s from tmpfs_nocacheread() and tmpfs_mappedwrite(). (The swap pager already spam your console if data corruption is imminent.) Reviewed by: kib MFC after: 3 weeks git-svn-id: http://svn.freebsd.org/base/head@230120 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f (cherry picked from commit 991f3065552e239942fff4db4569f02520657c54) Signed-off-by: Xin Li --- sys/fs/tmpfs/tmpfs_subr.c | 2 +- sys/fs/tmpfs/tmpfs_vnops.c | 40 ++++++++++++++++++++-------------------- 2 files changed, 21 insertions(+), 21 deletions(-) diff --git a/sys/fs/tmpfs/tmpfs_subr.c b/sys/fs/tmpfs/tmpfs_subr.c index e733f19..94bc0bf 100644 --- a/sys/fs/tmpfs/tmpfs_subr.c +++ b/sys/fs/tmpfs/tmpfs_subr.c @@ -929,6 +929,7 @@ retry: vm_page_sleep(m, "tmfssz"); goto retry; } + MPASS(m->valid == VM_PAGE_BITS_ALL); } else if (vm_pager_has_page(uobj, idx, NULL, NULL)) { m = vm_page_alloc(uobj, idx, VM_ALLOC_NORMAL); if (m == NULL) { @@ -957,7 +958,6 @@ retry: } if (m != NULL) { pmap_zero_page_area(m, base, PAGE_SIZE - base); - MPASS(m->valid == VM_PAGE_BITS_ALL); vm_page_dirty(m); vm_pager_page_unswapped(m); } diff --git a/sys/fs/tmpfs/tmpfs_vnops.c b/sys/fs/tmpfs/tmpfs_vnops.c index 0abd3c7..f0dfe36 100644 --- a/sys/fs/tmpfs/tmpfs_vnops.c +++ b/sys/fs/tmpfs/tmpfs_vnops.c @@ -437,18 +437,20 @@ tmpfs_nocacheread(vm_object_t tobj, vm_pindex_t idx, vm_offset_t offset, size_t tlen, struct uio *uio) { vm_page_t m; - int error; + int error, rv; VM_OBJECT_LOCK(tobj); - vm_object_pip_add(tobj, 1); m = vm_page_grab(tobj, idx, VM_ALLOC_WIRED | VM_ALLOC_NORMAL | VM_ALLOC_RETRY); if (m->valid != VM_PAGE_BITS_ALL) { if (vm_pager_has_page(tobj, idx, NULL, NULL)) { - error = vm_pager_get_pages(tobj, &m, 1, 0); - if (error != 0) { - printf("tmpfs get pages from pager error [read]\n"); - goto out; + rv = vm_pager_get_pages(tobj, &m, 1, 0); + if (rv != VM_PAGER_OK) { + vm_page_lock(m); + vm_page_free(m); + vm_page_unlock(m); + VM_OBJECT_UNLOCK(tobj); + return (EIO); } } else vm_page_zero_invalid(m, TRUE); @@ -456,12 +458,10 @@ tmpfs_nocacheread(vm_object_t tobj, vm_pindex_t idx, VM_OBJECT_UNLOCK(tobj); error = uiomove_fromphys(&m, offset, tlen, uio); VM_OBJECT_LOCK(tobj); -out: vm_page_lock(m); vm_page_unwire(m, TRUE); vm_page_unlock(m); vm_page_wakeup(m); - vm_object_pip_subtract(tobj, 1); VM_OBJECT_UNLOCK(tobj); return (error); @@ -624,7 +624,7 @@ tmpfs_mappedwrite(vm_object_t vobj, vm_object_t tobj, size_t len, struct uio *ui vm_offset_t offset; off_t addr; size_t tlen; - int error; + int error, rv; error = 0; @@ -664,14 +664,16 @@ lookupvpg: } nocache: VM_OBJECT_LOCK(tobj); - vm_object_pip_add(tobj, 1); tpg = vm_page_grab(tobj, idx, VM_ALLOC_WIRED | VM_ALLOC_NORMAL | VM_ALLOC_RETRY); if (tpg->valid != VM_PAGE_BITS_ALL) { if (vm_pager_has_page(tobj, idx, NULL, NULL)) { - error = vm_pager_get_pages(tobj, &tpg, 1, 0); - if (error != 0) { - printf("tmpfs get pages from pager error [write]\n"); + rv = vm_pager_get_pages(tobj, &tpg, 1, 0); + if (rv != VM_PAGER_OK) { + vm_page_lock(tpg); + vm_page_free(tpg); + vm_page_unlock(tpg); + error = EIO; goto out; } } else @@ -685,9 +687,6 @@ nocache: pmap_copy_page(vpg, tpg); } VM_OBJECT_LOCK(tobj); -out: - if (vobj != NULL) - VM_OBJECT_LOCK(vobj); if (error == 0) { KASSERT(tpg->valid == VM_PAGE_BITS_ALL, ("parts of tpg invalid")); @@ -697,12 +696,13 @@ out: vm_page_unwire(tpg, TRUE); vm_page_unlock(tpg); vm_page_wakeup(tpg); - if (vpg != NULL) +out: + VM_OBJECT_UNLOCK(tobj); + if (vpg != NULL) { + VM_OBJECT_LOCK(vobj); vm_page_wakeup(vpg); - if (vobj != NULL) VM_OBJECT_UNLOCK(vobj); - vm_object_pip_subtract(tobj, 1); - VM_OBJECT_UNLOCK(tobj); + } return (error); } -- 1.7.9.4