Date: Fri, 7 Aug 2015 16:38:44 +0300 From: Gleb Smirnoff <glebius@FreeBSD.org> To: arch@FreeBSD.org Subject: Re: more strict KPI for vm_pager_get_pages() Message-ID: <20150807133844.GS889@FreeBSD.org> In-Reply-To: <20150430142408.GS546@nginx.com> References: <20150430142408.GS546@nginx.com>
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--sLx0z+5FKKtIVDwd Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Hi! This is followup on older email: https://lists.freebsd.org/pipermail/freebsd-arch/2015-April/017154.html The preparatory commits were already checked in, and I'm going to push next week the rest, since the whole story is already several months due. Planned changes: o vm_pager_get_pages() accepts array of pages, and treats all pages equally. Notion of reqpage goes away. o The array span validity must be checked before with vm_pager_has_page(). o All pages must be xbusied on enter. o All pages will be left xbusied on exit. This closes possible races, allows to pass in wired pages (for any pager). And it leaves the caller to decide what to do with pages: vm_page_active, vm_page_deactivate, vm_page_flash or just vm_page_free them. The patch has been tested by me and pho@ with his stress2 test. I know, that there are two comments from kib@ on the patch. 1) There could be a user of KPI who would be fine with partial success. My answer: right now there is none, and if one emerges, the code can be easily adopted to return VM_PAGER_ERROR, but still mark validated pages as valid. The user of KPI then can scan the array and take valid pages. So, the patch doesn't put any obstacles on appearance of such user. 2) Filesystems can do short reads by design, and thus fail to validate the entire array. My answer: yes, that's true. By design NFS, SMBFS and FUSE should be able to return short reads. However, the VOP_GETPAGES methods for all three FSes right now do not have any code that would support that. So, it looks like there is an open issue with these filesystems, not related to my patch. When this issue is addressed in any of aforementioned FSes, the VOP_GETPAGES should be fixed to do several I/Os in case of short reads. -- Totus tuus, Glebius. --sLx0z+5FKKtIVDwd Content-Type: text/x-diff; charset=us-ascii Content-Disposition: attachment; filename="vm_pager_get_pages.diff" Index: sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vnops.c =================================================================== --- sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vnops.c (revision 286413) +++ sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vnops.c (working copy) @@ -5712,12 +5712,12 @@ ioflags(int ioflags) } static int -zfs_getpages(struct vnode *vp, vm_page_t *m, int count, int reqpage) +zfs_getpages(struct vnode *vp, vm_page_t *m, int count) { znode_t *zp = VTOZ(vp); zfsvfs_t *zfsvfs = zp->z_zfsvfs; objset_t *os = zp->z_zfsvfs->z_os; - vm_page_t mfirst, mlast, mreq; + vm_page_t mlast; vm_object_t object; caddr_t va; struct sf_buf *sf; @@ -5730,78 +5730,37 @@ static int ZFS_VERIFY_ZP(zp); pcount = OFF_TO_IDX(round_page(count)); - mreq = m[reqpage]; - object = mreq->object; - error = 0; - if (pcount > 1 && zp->z_blksz > PAGESIZE) { - startoff = rounddown(IDX_TO_OFF(mreq->pindex), zp->z_blksz); - reqstart = OFF_TO_IDX(round_page(startoff)); - if (reqstart < m[0]->pindex) - reqstart = 0; - else - reqstart = reqstart - m[0]->pindex; - endoff = roundup(IDX_TO_OFF(mreq->pindex) + PAGE_SIZE, - zp->z_blksz); - reqend = OFF_TO_IDX(trunc_page(endoff)) - 1; - if (reqend > m[pcount - 1]->pindex) - reqend = m[pcount - 1]->pindex; - reqsize = reqend - m[reqstart]->pindex + 1; - KASSERT(reqstart <= reqpage && reqpage < reqstart + reqsize, - ("reqpage beyond [reqstart, reqstart + reqsize[ bounds")); - } else { - reqstart = reqpage; - reqsize = 1; - } - mfirst = m[reqstart]; - mlast = m[reqstart + reqsize - 1]; - zfs_vmobject_wlock(object); - - for (i = 0; i < reqstart; i++) { - vm_page_lock(m[i]); - vm_page_free(m[i]); - vm_page_unlock(m[i]); - } - for (i = reqstart + reqsize; i < pcount; i++) { - vm_page_lock(m[i]); - vm_page_free(m[i]); - vm_page_unlock(m[i]); - } - - if (mreq->valid && reqsize == 1) { - if (mreq->valid != VM_PAGE_BITS_ALL) - vm_page_zero_invalid(mreq, TRUE); + if (m[pcount - 1]->valid != 0 && --pcount == 0) { zfs_vmobject_wunlock(object); ZFS_EXIT(zfsvfs); return (zfs_vm_pagerret_ok); } - PCPU_INC(cnt.v_vnodein); - PCPU_ADD(cnt.v_vnodepgsin, reqsize); + object = m[0]->object; + mlast = m[pcount - 1]; - if (IDX_TO_OFF(mreq->pindex) >= object->un_pager.vnp.vnp_size) { - for (i = reqstart; i < reqstart + reqsize; i++) { - if (i != reqpage) { - vm_page_lock(m[i]); - vm_page_free(m[i]); - vm_page_unlock(m[i]); - } - } + if (IDX_TO_OFF(mlast->pindex) >= + object->un_pager.vnp.vnp_size) { zfs_vmobject_wunlock(object); ZFS_EXIT(zfsvfs); return (zfs_vm_pagerret_bad); } + PCPU_INC(cnt.v_vnodein); + PCPU_ADD(cnt.v_vnodepgsin, reqsize); + lsize = PAGE_SIZE; if (IDX_TO_OFF(mlast->pindex) + lsize > object->un_pager.vnp.vnp_size) - lsize = object->un_pager.vnp.vnp_size - IDX_TO_OFF(mlast->pindex); - + lsize = object->un_pager.vnp.vnp_size - + IDX_TO_OFF(mlast->pindex); zfs_vmobject_wunlock(object); - for (i = reqstart; i < reqstart + reqsize; i++) { + error = 0; + for (i = 0; i < pcount; i++) { size = PAGE_SIZE; - if (i == (reqstart + reqsize - 1)) + if (i == pcount - 1) size = lsize; va = zfs_map_page(m[i], &sf); error = dmu_read(os, zp->z_id, IDX_TO_OFF(m[i]->pindex), @@ -5810,21 +5769,15 @@ static int bzero(va + size, PAGE_SIZE - size); zfs_unmap_page(sf); if (error != 0) - break; + goto out; } zfs_vmobject_wlock(object); - - for (i = reqstart; i < reqstart + reqsize; i++) { - if (!error) - m[i]->valid = VM_PAGE_BITS_ALL; - KASSERT(m[i]->dirty == 0, ("zfs_getpages: page %p is dirty", m[i])); - if (i != reqpage) - vm_page_readahead_finish(m[i]); - } - + for (i = 0; i < pcount; i++) + m[i]->valid = VM_PAGE_BITS_ALL; zfs_vmobject_wunlock(object); +out: ZFS_ACCESSTIME_STAMP(zfsvfs, zp); ZFS_EXIT(zfsvfs); return (error ? zfs_vm_pagerret_error : zfs_vm_pagerret_ok); @@ -5840,7 +5793,7 @@ zfs_freebsd_getpages(ap) } */ *ap; { - return (zfs_getpages(ap->a_vp, ap->a_m, ap->a_count, ap->a_reqpage)); + return (zfs_getpages(ap->a_vp, ap->a_m, ap->a_count)); } static int Index: sys/dev/drm2/i915/i915_gem.c =================================================================== --- sys/dev/drm2/i915/i915_gem.c (revision 286413) +++ sys/dev/drm2/i915/i915_gem.c (working copy) @@ -4326,7 +4326,7 @@ i915_gem_wire_page(vm_object_t object, vm_pindex_t page = vm_page_grab(object, pindex, VM_ALLOC_NORMAL); if (page->valid != VM_PAGE_BITS_ALL) { if (vm_pager_has_page(object, pindex, NULL, NULL)) { - rv = vm_pager_get_pages(object, &page, 1, 0); + rv = vm_pager_get_pages(object, &page, 1); if (rv != VM_PAGER_OK) { vm_page_lock(page); vm_page_free(page); Index: sys/dev/drm2/ttm/ttm_tt.c =================================================================== --- sys/dev/drm2/ttm/ttm_tt.c (revision 286413) +++ sys/dev/drm2/ttm/ttm_tt.c (working copy) @@ -291,7 +291,7 @@ int ttm_tt_swapin(struct ttm_tt *ttm) from_page = vm_page_grab(obj, i, VM_ALLOC_NORMAL); if (from_page->valid != VM_PAGE_BITS_ALL) { if (vm_pager_has_page(obj, i, NULL, NULL)) { - rv = vm_pager_get_pages(obj, &from_page, 1, 0); + rv = vm_pager_get_pages(obj, &from_page, 1); if (rv != VM_PAGER_OK) { vm_page_lock(from_page); vm_page_free(from_page); Index: sys/dev/md/md.c =================================================================== --- sys/dev/md/md.c (revision 286413) +++ sys/dev/md/md.c (working copy) @@ -835,7 +835,7 @@ mdstart_swap(struct md_s *sc, struct bio *bp) if (m->valid == VM_PAGE_BITS_ALL) rv = VM_PAGER_OK; else - rv = vm_pager_get_pages(sc->object, &m, 1, 0); + rv = vm_pager_get_pages(sc->object, &m, 1); if (rv == VM_PAGER_ERROR) { vm_page_xunbusy(m); break; @@ -858,7 +858,7 @@ mdstart_swap(struct md_s *sc, struct bio *bp) } } else if (bp->bio_cmd == BIO_WRITE) { if (len != PAGE_SIZE && m->valid != VM_PAGE_BITS_ALL) - rv = vm_pager_get_pages(sc->object, &m, 1, 0); + rv = vm_pager_get_pages(sc->object, &m, 1); else rv = VM_PAGER_OK; if (rv == VM_PAGER_ERROR) { @@ -874,7 +874,7 @@ mdstart_swap(struct md_s *sc, struct bio *bp) m->valid = VM_PAGE_BITS_ALL; } else if (bp->bio_cmd == BIO_DELETE) { if (len != PAGE_SIZE && m->valid != VM_PAGE_BITS_ALL) - rv = vm_pager_get_pages(sc->object, &m, 1, 0); + rv = vm_pager_get_pages(sc->object, &m, 1); else rv = VM_PAGER_OK; if (rv == VM_PAGER_ERROR) { Index: sys/fs/fuse/fuse_vnops.c =================================================================== --- sys/fs/fuse/fuse_vnops.c (revision 286413) +++ sys/fs/fuse/fuse_vnops.c (working copy) @@ -1761,26 +1761,21 @@ fuse_vnop_getpages(struct vop_getpages_args *ap) npages = btoc(count); /* - * If the requested page is partially valid, just return it and - * allow the pager to zero-out the blanks. Partially valid pages - * can only occur at the file EOF. + * If the last page is partially valid, just return it and allow + * the pager to zero-out the blanks. Partially valid pages can + * only occur at the file EOF. + * + * XXXGL: is that true for FUSE, which is a local filesystem, + * but still somewhat disconnected from the kernel? */ - VM_OBJECT_WLOCK(vp->v_object); - fuse_vm_page_lock_queues(); - if (pages[ap->a_reqpage]->valid != 0) { - for (i = 0; i < npages; ++i) { - if (i != ap->a_reqpage) { - fuse_vm_page_lock(pages[i]); - vm_page_free(pages[i]); - fuse_vm_page_unlock(pages[i]); - } + if (pages[npages - 1]->valid != 0) { + if (--npages == 0) { + VM_OBJECT_WUNLOCK(vp->v_object); + return (VM_PAGER_OK); } - fuse_vm_page_unlock_queues(); - VM_OBJECT_WUNLOCK(vp->v_object); - return 0; - } - fuse_vm_page_unlock_queues(); + count = npages << PAGE_SHIFT; + } VM_OBJECT_WUNLOCK(vp->v_object); /* @@ -1811,17 +1806,6 @@ fuse_vnop_getpages(struct vop_getpages_args *ap) if (error && (uio.uio_resid == count)) { FS_DEBUG("error %d\n", error); - VM_OBJECT_WLOCK(vp->v_object); - fuse_vm_page_lock_queues(); - for (i = 0; i < npages; ++i) { - if (i != ap->a_reqpage) { - fuse_vm_page_lock(pages[i]); - vm_page_free(pages[i]); - fuse_vm_page_unlock(pages[i]); - } - } - fuse_vm_page_unlock_queues(); - VM_OBJECT_WUNLOCK(vp->v_object); return VM_PAGER_ERROR; } /* @@ -1862,8 +1846,6 @@ fuse_vnop_getpages(struct vop_getpages_args *ap) */ ; } - if (i != ap->a_reqpage) - vm_page_readahead_finish(m); } fuse_vm_page_unlock_queues(); VM_OBJECT_WUNLOCK(vp->v_object); Index: sys/fs/nfsclient/nfs_clbio.c =================================================================== --- sys/fs/nfsclient/nfs_clbio.c (revision 286413) +++ sys/fs/nfsclient/nfs_clbio.c (working copy) @@ -132,12 +132,18 @@ ncl_getpages(struct vop_getpages_args *ap) * If the requested page is partially valid, just return it and * allow the pager to zero-out the blanks. Partially valid pages * can only occur at the file EOF. + * + * XXXGL: is that true for NFS, where short read can occur??? */ - if (pages[ap->a_reqpage]->valid != 0) { - vm_pager_free_nonreq(object, pages, ap->a_reqpage, npages, - FALSE); - return (VM_PAGER_OK); + VM_OBJECT_WLOCK(object); + if (pages[npages - 1]->valid != 0) { + if (--npages == 0) { + VM_OBJECT_WUNLOCK(object); + return (VM_PAGER_OK); + } + count = npages << PAGE_SHIFT; } + VM_OBJECT_WUNLOCK(object); /* * We use only the kva address for the buffer, but this is extremely @@ -167,8 +173,6 @@ ncl_getpages(struct vop_getpages_args *ap) if (error && (uio.uio_resid == count)) { ncl_printf("nfs_getpages: error %d\n", error); - vm_pager_free_nonreq(object, pages, ap->a_reqpage, npages, - FALSE); return (VM_PAGER_ERROR); } @@ -212,8 +216,6 @@ ncl_getpages(struct vop_getpages_args *ap) */ ; } - if (i != ap->a_reqpage) - vm_page_readahead_finish(m); } VM_OBJECT_WUNLOCK(object); return (0); Index: sys/fs/smbfs/smbfs_io.c =================================================================== --- sys/fs/smbfs/smbfs_io.c (revision 286413) +++ sys/fs/smbfs/smbfs_io.c (working copy) @@ -424,7 +424,7 @@ smbfs_getpages(ap) #ifdef SMBFS_RWGENERIC return vop_stdgetpages(ap); #else - int i, error, nextoff, size, toff, npages, count, reqpage; + int i, error, nextoff, size, toff, npages, count; struct uio uio; struct iovec iov; vm_offset_t kva; @@ -436,7 +436,7 @@ smbfs_getpages(ap) struct smbnode *np; struct smb_cred *scred; vm_object_t object; - vm_page_t *pages, m; + vm_page_t *pages; vp = ap->a_vp; if ((object = vp->v_object) == NULL) { @@ -451,26 +451,21 @@ smbfs_getpages(ap) pages = ap->a_m; count = ap->a_count; npages = btoc(count); - reqpage = ap->a_reqpage; /* * If the requested page is partially valid, just return it and * allow the pager to zero-out the blanks. Partially valid pages * can only occur at the file EOF. + * + * XXXGL: is that true for SMB filesystem? */ - m = pages[reqpage]; - VM_OBJECT_WLOCK(object); - if (m->valid != 0) { - for (i = 0; i < npages; ++i) { - if (i != reqpage) { - vm_page_lock(pages[i]); - vm_page_free(pages[i]); - vm_page_unlock(pages[i]); - } + if (pages[npages - 1]->valid != 0) { + if (--npages == 0) { + VM_OBJECT_WUNLOCK(object); + return (VM_PAGER_OK); } - VM_OBJECT_WUNLOCK(object); - return 0; + count = npages << PAGE_SHIFT; } VM_OBJECT_WUNLOCK(object); @@ -500,22 +495,14 @@ smbfs_getpages(ap) relpbuf(bp, &smbfs_pbuf_freecnt); - VM_OBJECT_WLOCK(object); if (error && (uio.uio_resid == count)) { printf("smbfs_getpages: error %d\n",error); - for (i = 0; i < npages; i++) { - if (reqpage != i) { - vm_page_lock(pages[i]); - vm_page_free(pages[i]); - vm_page_unlock(pages[i]); - } - } - VM_OBJECT_WUNLOCK(object); return VM_PAGER_ERROR; } size = count - uio.uio_resid; + VM_OBJECT_WLOCK(object); for (i = 0, toff = 0; i < npages; i++, toff = nextoff) { vm_page_t m; nextoff = toff + PAGE_SIZE; @@ -544,9 +531,6 @@ smbfs_getpages(ap) */ ; } - - if (i != reqpage) - vm_page_readahead_finish(m); } VM_OBJECT_WUNLOCK(object); return 0; Index: sys/fs/tmpfs/tmpfs_subr.c =================================================================== --- sys/fs/tmpfs/tmpfs_subr.c (revision 286413) +++ sys/fs/tmpfs/tmpfs_subr.c (working copy) @@ -1370,7 +1370,7 @@ retry: VM_OBJECT_WLOCK(uobj); goto retry; } else if (m->valid != VM_PAGE_BITS_ALL) - rv = vm_pager_get_pages(uobj, &m, 1, 0); + rv = vm_pager_get_pages(uobj, &m, 1); else /* A cached page was reactivated. */ rv = VM_PAGER_OK; Index: sys/kern/kern_exec.c =================================================================== --- sys/kern/kern_exec.c (revision 286413) +++ sys/kern/kern_exec.c (working copy) @@ -940,8 +940,7 @@ int exec_map_first_page(imgp) struct image_params *imgp; { - int rv, i; - int initial_pagein; + int rv, i, after, initial_pagein; vm_page_t ma[VM_INITIAL_PAGEIN]; vm_object_t object; @@ -957,9 +956,18 @@ exec_map_first_page(imgp) #endif ma[0] = vm_page_grab(object, 0, VM_ALLOC_NORMAL); if (ma[0]->valid != VM_PAGE_BITS_ALL) { - initial_pagein = VM_INITIAL_PAGEIN; - if (initial_pagein > object->size) - initial_pagein = object->size; + if (!vm_pager_has_page(object, 0, NULL, &after)) { + vm_page_xunbusy(ma[0]); + vm_page_lock(ma[0]); + vm_page_free(ma[0]); + vm_page_unlock(ma[0]); + VM_OBJECT_WUNLOCK(object); + return (EIO); + } + initial_pagein = min(after, VM_INITIAL_PAGEIN); + KASSERT(initial_pagein <= object->size, + ("%s: initial_pagein %d object->size %ju", + __func__, initial_pagein, (uintmax_t )object->size)); for (i = 1; i < initial_pagein; i++) { if ((ma[i] = vm_page_next(ma[i - 1])) != NULL) { if (ma[i]->valid) @@ -974,16 +982,21 @@ exec_map_first_page(imgp) } } initial_pagein = i; - rv = vm_pager_get_pages(object, ma, initial_pagein, 0); + rv = vm_pager_get_pages(object, ma, initial_pagein); if (rv != VM_PAGER_OK) { - vm_page_lock(ma[0]); - vm_page_free(ma[0]); - vm_page_unlock(ma[0]); + for (i = 0; i < initial_pagein; i++) { + vm_page_xunbusy(ma[i]); + vm_page_lock(ma[i]); + vm_page_free(ma[i]); + vm_page_unlock(ma[i]); + } VM_OBJECT_WUNLOCK(object); return (EIO); } - } - vm_page_xunbusy(ma[0]); + } else + initial_pagein = 1; + for (i = 0; i < initial_pagein; i++) + vm_page_xunbusy(ma[i]); vm_page_lock(ma[0]); vm_page_hold(ma[0]); vm_page_activate(ma[0]); Index: sys/kern/uipc_shm.c =================================================================== --- sys/kern/uipc_shm.c (revision 286413) +++ sys/kern/uipc_shm.c (working copy) @@ -189,7 +189,7 @@ uiomove_object_page(vm_object_t obj, size_t len, s m = vm_page_grab(obj, idx, VM_ALLOC_NORMAL); if (m->valid != VM_PAGE_BITS_ALL) { if (vm_pager_has_page(obj, idx, NULL, NULL)) { - rv = vm_pager_get_pages(obj, &m, 1, 0); + rv = vm_pager_get_pages(obj, &m, 1); if (rv != VM_PAGER_OK) { printf( "uiomove_object: vm_obj %p idx %jd valid %x pager error %d\n", @@ -459,8 +459,7 @@ retry: VM_OBJECT_WLOCK(object); goto retry; } else if (m->valid != VM_PAGE_BITS_ALL) - rv = vm_pager_get_pages(object, &m, 1, - 0); + rv = vm_pager_get_pages(object, &m, 1); else /* A cached page was reactivated. */ rv = VM_PAGER_OK; Index: sys/kern/uipc_syscalls.c =================================================================== --- sys/kern/uipc_syscalls.c (revision 286413) +++ sys/kern/uipc_syscalls.c (working copy) @@ -2033,7 +2033,7 @@ sendfile_readpage(vm_object_t obj, struct vnode *v VM_OBJECT_WLOCK(obj); } else { if (vm_pager_has_page(obj, pindex, NULL, NULL)) { - rv = vm_pager_get_pages(obj, &m, 1, 0); + rv = vm_pager_get_pages(obj, &m, 1); SFSTAT_INC(sf_iocnt); if (rv != VM_PAGER_OK) { vm_page_lock(m); Index: sys/kern/vfs_default.c =================================================================== --- sys/kern/vfs_default.c (revision 286413) +++ sys/kern/vfs_default.c (working copy) @@ -731,12 +731,11 @@ vop_stdgetpages(ap) struct vnode *a_vp; vm_page_t *a_m; int a_count; - int a_reqpage; } */ *ap; { return vnode_pager_generic_getpages(ap->a_vp, ap->a_m, - ap->a_count, ap->a_reqpage, NULL, NULL); + ap->a_count, NULL, NULL); } static int @@ -744,8 +743,8 @@ vop_stdgetpages_async(struct vop_getpages_async_ar { int error; - error = VOP_GETPAGES(ap->a_vp, ap->a_m, ap->a_count, ap->a_reqpage); - ap->a_iodone(ap->a_arg, ap->a_m, ap->a_reqpage, error); + error = VOP_GETPAGES(ap->a_vp, ap->a_m, ap->a_count); + ap->a_iodone(ap->a_arg, ap->a_m, ap->a_count, error); return (error); } Index: sys/kern/vnode_if.src =================================================================== --- sys/kern/vnode_if.src (revision 286413) +++ sys/kern/vnode_if.src (working copy) @@ -472,7 +472,6 @@ vop_getpages { IN struct vnode *vp; IN vm_page_t *m; IN int count; - IN int reqpage; }; @@ -482,7 +481,6 @@ vop_getpages_async { IN struct vnode *vp; IN vm_page_t *m; IN int count; - IN int reqpage; IN vop_getpages_iodone_t *iodone; IN void *arg; }; Index: sys/sys/buf.h =================================================================== --- sys/sys/buf.h (revision 286413) +++ sys/sys/buf.h (working copy) @@ -122,14 +122,9 @@ struct buf { struct ucred *b_rcred; /* Read credentials reference. */ struct ucred *b_wcred; /* Write credentials reference. */ union { - TAILQ_ENTRY(buf) bu_freelist; /* (Q) */ - struct { - void (*pg_iodone)(void *, vm_page_t *, int, int); - int pg_reqpage; - } bu_pager; - } b_union; -#define b_freelist b_union.bu_freelist -#define b_pager b_union.bu_pager + TAILQ_ENTRY(buf) b_freelist; /* (Q) */ + void (*b_pgiodone)(void *, vm_page_t *, int, int); + }; union cluster_info { TAILQ_HEAD(cluster_list_head, buf) cluster_head; TAILQ_ENTRY(buf) cluster_entry; Index: sys/vm/default_pager.c =================================================================== --- sys/vm/default_pager.c (revision 286413) +++ sys/vm/default_pager.c (working copy) @@ -56,7 +56,7 @@ __FBSDID("$FreeBSD$"); static vm_object_t default_pager_alloc(void *, vm_ooffset_t, vm_prot_t, vm_ooffset_t, struct ucred *); static void default_pager_dealloc(vm_object_t); -static int default_pager_getpages(vm_object_t, vm_page_t *, int, int); +static int default_pager_getpages(vm_object_t, vm_page_t *, int); static void default_pager_putpages(vm_object_t, vm_page_t *, int, boolean_t, int *); static boolean_t default_pager_haspage(vm_object_t, vm_pindex_t, int *, @@ -122,11 +122,10 @@ default_pager_dealloc(object) * see a vm_page with assigned swap here. */ static int -default_pager_getpages(object, m, count, reqpage) +default_pager_getpages(object, m, count) vm_object_t object; vm_page_t *m; int count; - int reqpage; { return VM_PAGER_FAIL; } Index: sys/vm/device_pager.c =================================================================== --- sys/vm/device_pager.c (revision 286413) +++ sys/vm/device_pager.c (working copy) @@ -59,7 +59,7 @@ static void dev_pager_init(void); static vm_object_t dev_pager_alloc(void *, vm_ooffset_t, vm_prot_t, vm_ooffset_t, struct ucred *); static void dev_pager_dealloc(vm_object_t); -static int dev_pager_getpages(vm_object_t, vm_page_t *, int, int); +static int dev_pager_getpages(vm_object_t, vm_page_t *, int); static void dev_pager_putpages(vm_object_t, vm_page_t *, int, boolean_t, int *); static boolean_t dev_pager_haspage(vm_object_t, vm_pindex_t, int *, @@ -259,33 +259,27 @@ dev_pager_dealloc(object) } static int -dev_pager_getpages(vm_object_t object, vm_page_t *ma, int count, int reqpage) +dev_pager_getpages(vm_object_t object, vm_page_t *ma, int count) { - int error, i; + int error; + /* Since our putpages reports zero after/before, the count is 1. */ + KASSERT(count == 1, ("%s: count %d", __func__, count)); VM_OBJECT_ASSERT_WLOCKED(object); error = object->un_pager.devp.ops->cdev_pg_fault(object, - IDX_TO_OFF(ma[reqpage]->pindex), PROT_READ, &ma[reqpage]); + IDX_TO_OFF(ma[0]->pindex), PROT_READ, &ma[0]); VM_OBJECT_ASSERT_WLOCKED(object); - for (i = 0; i < count; i++) { - if (i != reqpage) { - vm_page_lock(ma[i]); - vm_page_free(ma[i]); - vm_page_unlock(ma[i]); - } - } - if (error == VM_PAGER_OK) { KASSERT((object->type == OBJT_DEVICE && - (ma[reqpage]->oflags & VPO_UNMANAGED) != 0) || + (ma[0]->oflags & VPO_UNMANAGED) != 0) || (object->type == OBJT_MGTDEVICE && - (ma[reqpage]->oflags & VPO_UNMANAGED) == 0), - ("Wrong page type %p %p", ma[reqpage], object)); + (ma[0]->oflags & VPO_UNMANAGED) == 0), + ("Wrong page type %p %p", ma[0], object)); if (object->type == OBJT_DEVICE) { TAILQ_INSERT_TAIL(&object->un_pager.devp.devp_pglist, - ma[reqpage], plinks.q); + ma[0], plinks.q); } } Index: sys/vm/phys_pager.c =================================================================== --- sys/vm/phys_pager.c (revision 286413) +++ sys/vm/phys_pager.c (working copy) @@ -139,7 +139,7 @@ phys_pager_dealloc(vm_object_t object) * Fill as many pages as vm_fault has allocated for us. */ static int -phys_pager_getpages(vm_object_t object, vm_page_t *m, int count, int reqpage) +phys_pager_getpages(vm_object_t object, vm_page_t *m, int count) { int i; @@ -154,13 +154,6 @@ static int ("phys_pager_getpages: partially valid page %p", m[i])); KASSERT(m[i]->dirty == 0, ("phys_pager_getpages: dirty page %p", m[i])); - /* The requested page must remain busy, the others not. */ - if (i == reqpage) { - vm_page_lock(m[i]); - vm_page_flash(m[i]); - vm_page_unlock(m[i]); - } else - vm_page_xunbusy(m[i]); } return (VM_PAGER_OK); } Index: sys/vm/sg_pager.c =================================================================== --- sys/vm/sg_pager.c (revision 286413) +++ sys/vm/sg_pager.c (working copy) @@ -49,7 +49,7 @@ __FBSDID("$FreeBSD$"); static vm_object_t sg_pager_alloc(void *, vm_ooffset_t, vm_prot_t, vm_ooffset_t, struct ucred *); static void sg_pager_dealloc(vm_object_t); -static int sg_pager_getpages(vm_object_t, vm_page_t *, int, int); +static int sg_pager_getpages(vm_object_t, vm_page_t *, int); static void sg_pager_putpages(vm_object_t, vm_page_t *, int, boolean_t, int *); static boolean_t sg_pager_haspage(vm_object_t, vm_pindex_t, int *, @@ -135,7 +135,7 @@ sg_pager_dealloc(vm_object_t object) } static int -sg_pager_getpages(vm_object_t object, vm_page_t *m, int count, int reqpage) +sg_pager_getpages(vm_object_t object, vm_page_t *m, int count) { struct sglist *sg; vm_page_t m_paddr, page; @@ -145,11 +145,13 @@ static int size_t space; int i; + /* Since our putpages reports zero after/before, the count is 1. */ + KASSERT(count == 1, ("%s: count %d", __func__, count)); VM_OBJECT_ASSERT_WLOCKED(object); sg = object->handle; memattr = object->memattr; VM_OBJECT_WUNLOCK(object); - offset = m[reqpage]->pindex; + offset = m[0]->pindex; /* * Lookup the physical address of the requested page. An initial @@ -178,7 +180,7 @@ static int } /* Return a fake page for the requested page. */ - KASSERT(!(m[reqpage]->flags & PG_FICTITIOUS), + KASSERT(!(m[0]->flags & PG_FICTITIOUS), ("backing page for SG is fake")); /* Construct a new fake page. */ @@ -185,17 +187,9 @@ static int page = vm_page_getfake(paddr, memattr); VM_OBJECT_WLOCK(object); TAILQ_INSERT_TAIL(&object->un_pager.sgp.sgp_pglist, page, plinks.q); - - /* Free the original pages and insert this fake page into the object. */ - for (i = 0; i < count; i++) { - if (i == reqpage && - vm_page_replace(page, object, offset) != m[i]) - panic("sg_pager_getpages: invalid place replacement"); - vm_page_lock(m[i]); - vm_page_free(m[i]); - vm_page_unlock(m[i]); - } - m[reqpage] = page; + if (vm_page_replace(page, object, offset) != m[0]) + panic("sg_pager_getpages: invalid place replacement"); + m[0] = page; page->valid = VM_PAGE_BITS_ALL; return (VM_PAGER_OK); Index: sys/vm/swap_pager.c =================================================================== --- sys/vm/swap_pager.c (revision 286413) +++ sys/vm/swap_pager.c (working copy) @@ -359,8 +359,8 @@ static vm_object_t swap_pager_alloc(void *handle, vm_ooffset_t size, vm_prot_t prot, vm_ooffset_t offset, struct ucred *); static void swap_pager_dealloc(vm_object_t object); -static int swap_pager_getpages(vm_object_t, vm_page_t *, int, int); -static int swap_pager_getpages_async(vm_object_t, vm_page_t *, int, int, +static int swap_pager_getpages(vm_object_t, vm_page_t *, int); +static int swap_pager_getpages_async(vm_object_t, vm_page_t *, int, pgo_getpages_iodone_t, void *); static void swap_pager_putpages(vm_object_t, vm_page_t *, int, boolean_t, int *); static boolean_t @@ -415,16 +415,6 @@ static void swp_pager_meta_free(vm_object_t, vm_pi static void swp_pager_meta_free_all(vm_object_t); static daddr_t swp_pager_meta_ctl(vm_object_t, vm_pindex_t, int); -static void -swp_pager_free_nrpage(vm_page_t m) -{ - - vm_page_lock(m); - if (m->wire_count == 0) - vm_page_free(m); - vm_page_unlock(m); -} - /* * SWP_SIZECHECK() - update swap_pager_full indication * @@ -1105,16 +1095,11 @@ swap_pager_unswapped(vm_page_t m) * left busy, but the others adjusted. */ static int -swap_pager_getpages(vm_object_t object, vm_page_t *m, int count, int reqpage) +swap_pager_getpages(vm_object_t object, vm_page_t *m, int count) { struct buf *bp; - vm_page_t mreq; - int i; - int j; daddr_t blk; - mreq = m[reqpage]; - /* * Calculate range to retrieve. The pages have already been assigned * their swapblks. We require a *contiguous* range but we know it to @@ -1124,45 +1109,18 @@ static int * * The swp_*() calls must be made with the object locked. */ - blk = swp_pager_meta_ctl(mreq->object, mreq->pindex, 0); + blk = swp_pager_meta_ctl(m[0]->object, m[0]->pindex, 0); - for (i = reqpage - 1; i >= 0; --i) { - daddr_t iblk; - - iblk = swp_pager_meta_ctl(m[i]->object, m[i]->pindex, 0); - if (blk != iblk + (reqpage - i)) - break; - } - ++i; - - for (j = reqpage + 1; j < count; ++j) { - daddr_t jblk; - - jblk = swp_pager_meta_ctl(m[j]->object, m[j]->pindex, 0); - if (blk != jblk - (j - reqpage)) - break; - } - - /* - * free pages outside our collection range. Note: we never free - * mreq, it must remain busy throughout. - */ - if (0 < i || j < count) { - int k; - - for (k = 0; k < i; ++k) - swp_pager_free_nrpage(m[k]); - for (k = j; k < count; ++k) - swp_pager_free_nrpage(m[k]); - } - - /* - * Return VM_PAGER_FAIL if we have nothing to do. Return mreq - * still busy, but the others unbusied. - */ if (blk == SWAPBLK_NONE) return (VM_PAGER_FAIL); +#ifdef INVARIANTS + for (int i = 0; i < count; i++) + KASSERT(blk + i == + swp_pager_meta_ctl(m[i]->object, m[i]->pindex, 0), + ("%s: range is not contiguous", __func__)); +#endif + /* * Getpbuf() can sleep. */ @@ -1177,21 +1135,16 @@ static int bp->b_iodone = swp_pager_async_iodone; bp->b_rcred = crhold(thread0.td_ucred); bp->b_wcred = crhold(thread0.td_ucred); - bp->b_blkno = blk - (reqpage - i); - bp->b_bcount = PAGE_SIZE * (j - i); - bp->b_bufsize = PAGE_SIZE * (j - i); - bp->b_pager.pg_reqpage = reqpage - i; + bp->b_blkno = blk; + bp->b_bcount = PAGE_SIZE * count; + bp->b_bufsize = PAGE_SIZE * count; + bp->b_npages = count; VM_OBJECT_WLOCK(object); - { - int k; - - for (k = i; k < j; ++k) { - bp->b_pages[k - i] = m[k]; - m[k]->oflags |= VPO_SWAPINPROG; - } + for (int i = 0; i < count; i++) { + bp->b_pages[i] = m[i]; + m[i]->oflags |= VPO_SWAPINPROG; } - bp->b_npages = j - i; PCPU_INC(cnt.v_swapin); PCPU_ADD(cnt.v_swappgsin, bp->b_npages); @@ -1223,8 +1176,8 @@ static int * is set in the meta-data. */ VM_OBJECT_WLOCK(object); - while ((mreq->oflags & VPO_SWAPINPROG) != 0) { - mreq->oflags |= VPO_SWAPSLEEP; + while ((m[0]->oflags & VPO_SWAPINPROG) != 0) { + m[0]->oflags |= VPO_SWAPSLEEP; PCPU_INC(cnt.v_intrans); if (VM_OBJECT_SLEEP(object, &object->paging_in_progress, PSWP, "swread", hz * 20)) { @@ -1235,16 +1188,14 @@ static int } /* - * mreq is left busied after completion, but all the other pages - * are freed. If we had an unrecoverable read error the page will - * not be valid. + * If we had an unrecoverable read error pages will not be valid. */ - if (mreq->valid != VM_PAGE_BITS_ALL) { - return (VM_PAGER_ERROR); - } else { - return (VM_PAGER_OK); - } + for (int i = 0; i < count; i++) + if (m[i]->valid != VM_PAGE_BITS_ALL) + return (VM_PAGER_ERROR); + return (VM_PAGER_OK); + /* * A final note: in a low swap situation, we cannot deallocate swap * and mark a page dirty here because the caller is likely to mark @@ -1261,11 +1212,11 @@ static int */ static int swap_pager_getpages_async(vm_object_t object, vm_page_t *m, int count, - int reqpage, pgo_getpages_iodone_t iodone, void *arg) + pgo_getpages_iodone_t iodone, void *arg) { int r, error; - r = swap_pager_getpages(object, m, count, reqpage); + r = swap_pager_getpages(object, m, count); VM_OBJECT_WUNLOCK(object); switch (r) { case VM_PAGER_OK: @@ -1529,33 +1480,11 @@ swp_pager_async_iodone(struct buf *bp) */ if (bp->b_iocmd == BIO_READ) { /* - * When reading, reqpage needs to stay - * locked for the parent, but all other - * pages can be freed. We still want to - * wakeup the parent waiting on the page, - * though. ( also: pg_reqpage can be -1 and - * not match anything ). - * - * We have to wake specifically requested pages - * up too because we cleared VPO_SWAPINPROG and - * someone may be waiting for that. - * * NOTE: for reads, m->dirty will probably * be overridden by the original caller of * getpages so don't play cute tricks here. */ m->valid = 0; - if (i != bp->b_pager.pg_reqpage) - swp_pager_free_nrpage(m); - else { - vm_page_lock(m); - vm_page_flash(m); - vm_page_unlock(m); - } - /* - * If i == bp->b_pager.pg_reqpage, do not wake - * the page up. The caller needs to. - */ } else { /* * If a write error occurs, reactivate page @@ -1577,38 +1506,12 @@ swp_pager_async_iodone(struct buf *bp) * want to do that anyway, but it was an optimization * that existed in the old swapper for a time before * it got ripped out due to precisely this problem. - * - * If not the requested page then deactivate it. - * - * Note that the requested page, reqpage, is left - * busied, but we still have to wake it up. The - * other pages are released (unbusied) by - * vm_page_xunbusy(). */ KASSERT(!pmap_page_is_mapped(m), ("swp_pager_async_iodone: page %p is mapped", m)); - m->valid = VM_PAGE_BITS_ALL; KASSERT(m->dirty == 0, ("swp_pager_async_iodone: page %p is dirty", m)); - - /* - * We have to wake specifically requested pages - * up too because we cleared VPO_SWAPINPROG and - * could be waiting for it in getpages. However, - * be sure to not unbusy getpages specifically - * requested page - getpages expects it to be - * left busy. - */ - if (i != bp->b_pager.pg_reqpage) { - vm_page_lock(m); - vm_page_deactivate(m); - vm_page_unlock(m); - vm_page_xunbusy(m); - } else { - vm_page_lock(m); - vm_page_flash(m); - vm_page_unlock(m); - } + m->valid = VM_PAGE_BITS_ALL; } else { /* * For write success, clear the dirty @@ -1729,7 +1632,7 @@ swp_pager_force_pagein(vm_object_t object, vm_pind return; } - if (swap_pager_getpages(object, &m, 1, 0) != VM_PAGER_OK) + if (swap_pager_getpages(object, &m, 1) != VM_PAGER_OK) panic("swap_pager_force_pagein: read from swap failed");/*XXX*/ vm_object_pip_wakeup(object); vm_page_dirty(m); Index: sys/vm/vm_fault.c =================================================================== --- sys/vm/vm_fault.c (revision 286413) +++ sys/vm/vm_fault.c (working copy) @@ -669,14 +669,20 @@ vnode_locked: fs.m, behind, ahead, marray, &reqpage); rv = faultcount ? - vm_pager_get_pages(fs.object, marray, faultcount, - reqpage) : VM_PAGER_FAIL; + vm_pager_get_pages(fs.object, marray, faultcount) : + VM_PAGER_FAIL; if (rv == VM_PAGER_OK) { /* * Found the page. Leave it busy while we play - * with it. - * + * with it. Unbusy companion pages. + */ + for (int i = 0; i < faultcount; i++) { + if (i == reqpage) + continue; + vm_page_readahead_finish(marray[i]); + } + /* * Pager could have changed the page. Pager * is responsible for disposition of old page * if moved. Index: sys/vm/vm_glue.c =================================================================== --- sys/vm/vm_glue.c (revision 286413) +++ sys/vm/vm_glue.c (working copy) @@ -238,7 +238,7 @@ vm_imgact_hold_page(vm_object_t object, vm_ooffset pindex = OFF_TO_IDX(offset); m = vm_page_grab(object, pindex, VM_ALLOC_NORMAL); if (m->valid != VM_PAGE_BITS_ALL) { - rv = vm_pager_get_pages(object, &m, 1, 0); + rv = vm_pager_get_pages(object, &m, 1); if (rv != VM_PAGER_OK) { vm_page_lock(m); vm_page_free(m); @@ -567,37 +567,37 @@ vm_thread_swapin(struct thread *td) { vm_object_t ksobj; vm_page_t ma[KSTACK_MAX_PAGES]; - int i, j, pages, rv; + int pages; pages = td->td_kstack_pages; ksobj = td->td_kstack_obj; VM_OBJECT_WLOCK(ksobj); - for (i = 0; i < pages; i++) + for (int i = 0; i < pages; i++) ma[i] = vm_page_grab(ksobj, i, VM_ALLOC_NORMAL | VM_ALLOC_WIRED); - for (i = 0; i < pages; i++) { - if (ma[i]->valid != VM_PAGE_BITS_ALL) { - vm_page_assert_xbusied(ma[i]); - vm_object_pip_add(ksobj, 1); - for (j = i + 1; j < pages; j++) { - if (ma[j]->valid != VM_PAGE_BITS_ALL) - vm_page_assert_xbusied(ma[j]); - if (ma[j]->valid == VM_PAGE_BITS_ALL) - break; - } - rv = vm_pager_get_pages(ksobj, ma + i, j - i, 0); - if (rv != VM_PAGER_OK) - panic("vm_thread_swapin: cannot get kstack for proc: %d", - td->td_proc->p_pid); - /* - * All pages in the array are in place, due to the - * pager is always the swap pager, which doesn't - * free or remove wired non-req pages from object. - */ - vm_object_pip_wakeup(ksobj); + for (int i = 0; i < pages;) { + int j, a, count, rv; + + vm_page_assert_xbusied(ma[i]); + if (ma[i]->valid == VM_PAGE_BITS_ALL) { vm_page_xunbusy(ma[i]); - } else if (vm_page_xbusied(ma[i])) - vm_page_xunbusy(ma[i]); + i++; + continue; + } + vm_object_pip_add(ksobj, 1); + for (j = i + 1; j < pages; j++) + if (ma[j]->valid == VM_PAGE_BITS_ALL) + break; + rv = vm_pager_has_page(ksobj, ma[i]->pindex, NULL, &a); + KASSERT(rv == 1, ("%s: missing page %p", __func__, ma[i])); + count = min(a + 1, j - i); + rv = vm_pager_get_pages(ksobj, ma + i, count); + KASSERT(rv == VM_PAGER_OK, ("%s: cannot get kstack for proc %d", + __func__, td->td_proc->p_pid)); + vm_object_pip_wakeup(ksobj); + for (j = i; j < i + count; j++) + vm_page_xunbusy(ma[j]); + i += count; } VM_OBJECT_WUNLOCK(ksobj); pmap_qenter(td->td_kstack, ma, pages); Index: sys/vm/vm_object.c =================================================================== --- sys/vm/vm_object.c (revision 286413) +++ sys/vm/vm_object.c (working copy) @@ -2036,7 +2036,7 @@ vm_object_populate(vm_object_t object, vm_pindex_t for (pindex = start; pindex < end; pindex++) { m = vm_page_grab(object, pindex, VM_ALLOC_NORMAL); if (m->valid != VM_PAGE_BITS_ALL) { - rv = vm_pager_get_pages(object, &m, 1, 0); + rv = vm_pager_get_pages(object, &m, 1); if (rv != VM_PAGER_OK) { vm_page_lock(m); vm_page_free(m); Index: sys/vm/vm_page.c =================================================================== --- sys/vm/vm_page.c (revision 286413) +++ sys/vm/vm_page.c (working copy) @@ -977,38 +977,28 @@ vm_page_free_zero(vm_page_t m) /* * Unbusy and handle the page queueing for a page from the VOP_GETPAGES() - * array which is not the request page. + * array which was read ahead. */ void vm_page_readahead_finish(vm_page_t m) { - if (m->valid != 0) { - /* - * Since the page is not the requested page, whether - * it should be activated or deactivated is not - * obvious. Empirical results have shown that - * deactivating the page is usually the best choice, - * unless the page is wanted by another thread. - */ - vm_page_lock(m); - if ((m->busy_lock & VPB_BIT_WAITERS) != 0) - vm_page_activate(m); - else - vm_page_deactivate(m); - vm_page_unlock(m); - vm_page_xunbusy(m); - } else { - /* - * Free the completely invalid page. Such page state - * occurs due to the short read operation which did - * not covered our page at all, or in case when a read - * error happens. - */ - vm_page_lock(m); - vm_page_free(m); - vm_page_unlock(m); - } + /* We shouldn't put invalid pages on queues. */ + KASSERT(m->valid != 0, ("%s: %p is invalid", __func__, m)); + + /* + * Since the page is not the actually needed one, whether it should + * be activated or deactivated is not obvious. Empirical results + * have shown that deactivating the page is usually the best choice, + * unless the page is wanted by another thread. + */ + vm_page_lock(m); + if ((m->busy_lock & VPB_BIT_WAITERS) != 0) + vm_page_activate(m); + else + vm_page_deactivate(m); + vm_page_unlock(m); + vm_page_xunbusy(m); } /* Index: sys/vm/vm_pager.c =================================================================== --- sys/vm/vm_pager.c (revision 286413) +++ sys/vm/vm_pager.c (working copy) @@ -282,45 +282,45 @@ vm_pager_assert_in(vm_object_t object, vm_page_t * * The requested page must be fully valid on successful return. */ int -vm_pager_get_pages(vm_object_t object, vm_page_t *m, int count, int reqpage) +vm_pager_get_pages(vm_object_t object, vm_page_t *m, int count) { +#ifdef INVARIANTS + vm_pindex_t pindex = m[0]->pindex; +#endif int r; vm_pager_assert_in(object, m, count); - r = (*pagertab[object->type]->pgo_getpages)(object, m, count, reqpage); + r = (*pagertab[object->type]->pgo_getpages)(object, m, count); if (r != VM_PAGER_OK) return (r); - /* - * If pager has replaced the page, assert that it had - * updated the array. Also assert that page is still - * busied. - */ - KASSERT(m[reqpage] == vm_page_lookup(object, m[reqpage]->pindex), - ("%s: mismatch page %p pindex %ju", __func__, - m[reqpage], (uintmax_t )m[reqpage]->pindex)); - vm_page_assert_xbusied(m[reqpage]); - - /* - * Pager didn't fill up entire page. Zero out - * partially filled data. - */ - if (m[reqpage]->valid != VM_PAGE_BITS_ALL) - vm_page_zero_invalid(m[reqpage], TRUE); - + for (int i = 0; i < count; i++) { + /* + * If pager has replaced a page, assert that it had + * updated the array. + */ + KASSERT(m[i] == vm_page_lookup(object, pindex++), + ("%s: mismatch page %p pindex %ju", __func__, + m[i], (uintmax_t )pindex - 1)); + /* + * Zero out partially filled data. + */ + if (m[i]->valid != VM_PAGE_BITS_ALL) + vm_page_zero_invalid(m[i], TRUE); + } return (VM_PAGER_OK); } int vm_pager_get_pages_async(vm_object_t object, vm_page_t *m, int count, - int reqpage, pgo_getpages_iodone_t iodone, void *arg) + pgo_getpages_iodone_t iodone, void *arg) { vm_pager_assert_in(object, m, count); return ((*pagertab[object->type]->pgo_getpages_async)(object, m, - count, reqpage, iodone, arg)); + count, iodone, arg)); } /* @@ -355,39 +355,6 @@ vm_pager_object_lookup(struct pagerlst *pg_list, v } /* - * Free the non-requested pages from the given array. To remove all pages, - * caller should provide out of range reqpage number. - */ -void -vm_pager_free_nonreq(vm_object_t object, vm_page_t ma[], int reqpage, - int npages, boolean_t object_locked) -{ - enum { UNLOCKED, CALLER_LOCKED, INTERNALLY_LOCKED } locked; - int i; - - if (object_locked) { - VM_OBJECT_ASSERT_WLOCKED(object); - locked = CALLER_LOCKED; - } else { - VM_OBJECT_ASSERT_UNLOCKED(object); - locked = UNLOCKED; - } - for (i = 0; i < npages; ++i) { - if (i != reqpage) { - if (locked == UNLOCKED) { - VM_OBJECT_WLOCK(object); - locked = INTERNALLY_LOCKED; - } - vm_page_lock(ma[i]); - vm_page_free(ma[i]); - vm_page_unlock(ma[i]); - } - } - if (locked == INTERNALLY_LOCKED) - VM_OBJECT_WUNLOCK(object); -} - -/* * initialize a physical buffer */ Index: sys/vm/vm_pager.h =================================================================== --- sys/vm/vm_pager.h (revision 286413) +++ sys/vm/vm_pager.h (working copy) @@ -50,9 +50,9 @@ typedef void pgo_init_t(void); typedef vm_object_t pgo_alloc_t(void *, vm_ooffset_t, vm_prot_t, vm_ooffset_t, struct ucred *); typedef void pgo_dealloc_t(vm_object_t); -typedef int pgo_getpages_t(vm_object_t, vm_page_t *, int, int); +typedef int pgo_getpages_t(vm_object_t, vm_page_t *, int); typedef void pgo_getpages_iodone_t(void *, vm_page_t *, int, int); -typedef int pgo_getpages_async_t(vm_object_t, vm_page_t *, int, int, +typedef int pgo_getpages_async_t(vm_object_t, vm_page_t *, int, pgo_getpages_iodone_t, void *); typedef void pgo_putpages_t(vm_object_t, vm_page_t *, int, int, int *); typedef boolean_t pgo_haspage_t(vm_object_t, vm_pindex_t, int *, int *); @@ -106,14 +106,12 @@ vm_object_t vm_pager_allocate(objtype_t, void *, v vm_ooffset_t, struct ucred *); void vm_pager_bufferinit(void); void vm_pager_deallocate(vm_object_t); -int vm_pager_get_pages(vm_object_t, vm_page_t *, int, int); -int vm_pager_get_pages_async(vm_object_t, vm_page_t *, int, int, +int vm_pager_get_pages(vm_object_t, vm_page_t *, int); +int vm_pager_get_pages_async(vm_object_t, vm_page_t *, int, pgo_getpages_iodone_t, void *); static __inline boolean_t vm_pager_has_page(vm_object_t, vm_pindex_t, int *, int *); void vm_pager_init(void); vm_object_t vm_pager_object_lookup(struct pagerlst *, void *); -void vm_pager_free_nonreq(vm_object_t object, vm_page_t ma[], int reqpage, - int npages, boolean_t object_locked); static __inline void vm_pager_put_pages( Index: sys/vm/vnode_pager.c =================================================================== --- sys/vm/vnode_pager.c (revision 286413) +++ sys/vm/vnode_pager.c (working copy) @@ -84,11 +84,9 @@ static int vnode_pager_addr(struct vnode *vp, vm_o static int vnode_pager_input_smlfs(vm_object_t object, vm_page_t m); static int vnode_pager_input_old(vm_object_t object, vm_page_t m); static void vnode_pager_dealloc(vm_object_t); -static int vnode_pager_local_getpages0(struct vnode *, vm_page_t *, int, int, +static int vnode_pager_getpages(vm_object_t, vm_page_t *, int); +static int vnode_pager_getpages_async(vm_object_t, vm_page_t *, int, vop_getpages_iodone_t, void *); -static int vnode_pager_getpages(vm_object_t, vm_page_t *, int, int); -static int vnode_pager_getpages_async(vm_object_t, vm_page_t *, int, int, - vop_getpages_iodone_t, void *); static void vnode_pager_putpages(vm_object_t, vm_page_t *, int, int, int *); static boolean_t vnode_pager_haspage(vm_object_t, vm_pindex_t, int *, int *); static vm_object_t vnode_pager_alloc(void *, vm_ooffset_t, vm_prot_t, @@ -673,7 +671,7 @@ vnode_pager_input_old(vm_object_t object, vm_page_ * backing vp's VOP_GETPAGES. */ static int -vnode_pager_getpages(vm_object_t object, vm_page_t *m, int count, int reqpage) +vnode_pager_getpages(vm_object_t object, vm_page_t *m, int count) { int rtval; struct vnode *vp; @@ -681,7 +679,7 @@ static int vp = object->handle; VM_OBJECT_WUNLOCK(object); - rtval = VOP_GETPAGES(vp, m, bytes, reqpage); + rtval = VOP_GETPAGES(vp, m, bytes); KASSERT(rtval != EOPNOTSUPP, ("vnode_pager: FS getpages not implemented\n")); VM_OBJECT_WLOCK(object); @@ -690,7 +688,7 @@ static int static int vnode_pager_getpages_async(vm_object_t object, vm_page_t *m, int count, - int reqpage, vop_getpages_iodone_t iodone, void *arg) + vop_getpages_iodone_t iodone, void *arg) { struct vnode *vp; int rtval; @@ -697,8 +695,7 @@ vnode_pager_getpages_async(vm_object_t object, vm_ vp = object->handle; VM_OBJECT_WUNLOCK(object); - rtval = VOP_GETPAGES_ASYNC(vp, m, count * PAGE_SIZE, reqpage, - iodone, arg); + rtval = VOP_GETPAGES_ASYNC(vp, m, count * PAGE_SIZE, iodone, arg); KASSERT(rtval != EOPNOTSUPP, ("vnode_pager: FS getpages_async not implemented\n")); VM_OBJECT_WLOCK(object); @@ -714,8 +711,8 @@ int vnode_pager_local_getpages(struct vop_getpages_args *ap) { - return (vnode_pager_local_getpages0(ap->a_vp, ap->a_m, ap->a_count, - ap->a_reqpage, NULL, NULL)); + return (vnode_pager_generic_getpages(ap->a_vp, ap->a_m, ap->a_count, + NULL, NULL)); } int @@ -722,42 +719,10 @@ int vnode_pager_local_getpages_async(struct vop_getpages_async_args *ap) { - return (vnode_pager_local_getpages0(ap->a_vp, ap->a_m, ap->a_count, - ap->a_reqpage, ap->a_iodone, ap->a_arg)); + return (vnode_pager_generic_getpages(ap->a_vp, ap->a_m, ap->a_count, + ap->a_iodone, ap->a_arg)); } -static int -vnode_pager_local_getpages0(struct vnode *vp, vm_page_t *m, int bytecount, - int reqpage, vop_getpages_iodone_t iodone, void *arg) -{ - vm_page_t mreq; - - mreq = m[reqpage]; - - /* - * Since the caller has busied the requested page, that page's valid - * field will not be changed by other threads. - */ - vm_page_assert_xbusied(mreq); - - /* - * The requested page has valid blocks. Invalid part can only - * exist at the end of file, and the page is made fully valid - * by zeroing in vm_pager_get_pages(). Free non-requested - * pages, since no i/o is done to read its content. - */ - if (mreq->valid != 0) { - vm_pager_free_nonreq(mreq->object, m, reqpage, - round_page(bytecount) / PAGE_SIZE, FALSE); - if (iodone != NULL) - iodone(arg, m, reqpage, 0); - return (VM_PAGER_OK); - } - - return (vnode_pager_generic_getpages(vp, m, bytecount, reqpage, - iodone, arg)); -} - /* * This is now called from local media FS's to operate against their * own vnodes if they fail to implement VOP_GETPAGES. @@ -764,31 +729,47 @@ vnode_pager_local_getpages_async(struct vop_getpag */ int vnode_pager_generic_getpages(struct vnode *vp, vm_page_t *m, int bytecount, - int reqpage, vop_getpages_iodone_t iodone, void *arg) + vop_getpages_iodone_t iodone, void *arg) { vm_object_t object; off_t foff; - int i, j, size, bsize, first, *freecnt; - daddr_t firstaddr, reqblock; + int error, count, bsize, i, after, secmask, *freecnt; + daddr_t reqblock; struct bufobj *bo; - int runpg; - int runend; struct buf *bp; - int count; - int error; - object = vp->v_object; - count = bytecount / PAGE_SIZE; + KASSERT(vp->v_type != VCHR && vp->v_type != VBLK, + ("%s does not support devices", __func__)); + KASSERT(bytecount > 0 && (bytecount & ~PAGE_MASK) == bytecount, + ("%s: bytecount %d", __func__, bytecount)); - KASSERT(vp->v_type != VCHR && vp->v_type != VBLK, - ("vnode_pager_generic_getpages does not support devices")); if (vp->v_iflag & VI_DOOMED) return VM_PAGER_BAD; + object = vp->v_object; + foff = IDX_TO_OFF(m[0]->pindex); + + KASSERT(foff < object->un_pager.vnp.vnp_size, + ("%s: page %p offset beyond vp %p size", __func__, m[0], vp)); + + count = bytecount >> PAGE_SHIFT; bsize = vp->v_mount->mnt_stat.f_iosize; - foff = IDX_TO_OFF(m[reqpage]->pindex); /* + * The last page has valid blocks. Invalid part can only + * exist at the end of file, and the page is made fully valid + * by zeroing in vm_pager_get_pages(). + */ + if (m[count - 1]->valid != 0) { + if ( --count == 0) { + if (iodone != NULL) + iodone(arg, m, 1, 0); + return (VM_PAGER_OK); + } + bytecount = count << PAGE_SHIFT; + } + + /* * Synchronous and asynchronous paging operations use different * free pbuf counters. This is done to avoid asynchronous requests * to consume all pbufs. @@ -805,168 +786,55 @@ vnode_pager_generic_getpages(struct vnode *vp, vm_ * If the file system doesn't support VOP_BMAP, use old way of * getting pages via VOP_READ. */ - error = VOP_BMAP(vp, foff / bsize, &bo, &reqblock, NULL, NULL); + error = VOP_BMAP(vp, foff / bsize, &bo, &reqblock, &after, NULL); if (error == EOPNOTSUPP) { relpbuf(bp, freecnt); VM_OBJECT_WLOCK(object); - for (i = 0; i < count; i++) - if (i != reqpage) { - vm_page_lock(m[i]); - vm_page_free(m[i]); - vm_page_unlock(m[i]); - } - PCPU_INC(cnt.v_vnodein); - PCPU_INC(cnt.v_vnodepgsin); - error = vnode_pager_input_old(object, m[reqpage]); + for (i = 0; i < count; i++) { + PCPU_INC(cnt.v_vnodein); + PCPU_INC(cnt.v_vnodepgsin); + error = vnode_pager_input_old(object, m[i]); + if (error) + break; + } VM_OBJECT_WUNLOCK(object); return (error); } else if (error != 0) { relpbuf(bp, freecnt); - vm_pager_free_nonreq(object, m, reqpage, count, FALSE); return (VM_PAGER_ERROR); - - /* - * if the blocksize is smaller than a page size, then use - * special small filesystem code. NFS sometimes has a small - * blocksize, but it can handle large reads itself. - */ - } else if ((PAGE_SIZE / bsize) > 1 && - (vp->v_mount->mnt_stat.f_type != nfs_mount_type)) { - relpbuf(bp, freecnt); - vm_pager_free_nonreq(object, m, reqpage, count, FALSE); - PCPU_INC(cnt.v_vnodein); - PCPU_INC(cnt.v_vnodepgsin); - return vnode_pager_input_smlfs(object, m[reqpage]); } /* - * Since the caller has busied the requested page, that page's valid - * field will not be changed by other threads. + * If the blocksize is smaller than a page size, then use + * special small filesystem code. NFS sometimes has a small + * blocksize, but it can handle large reads itself. */ - vm_page_assert_xbusied(m[reqpage]); - - /* - * If we have a completely valid page available to us, we can - * clean up and return. Otherwise we have to re-read the - * media. - */ - if (m[reqpage]->valid == VM_PAGE_BITS_ALL) { + if ((PAGE_SIZE / bsize) > 1 && + (vp->v_mount->mnt_stat.f_type != nfs_mount_type)) { relpbuf(bp, freecnt); - vm_pager_free_nonreq(object, m, reqpage, count, FALSE); - return (VM_PAGER_OK); - } else if (reqblock == -1) { - relpbuf(bp, freecnt); - pmap_zero_page(m[reqpage]); - KASSERT(m[reqpage]->dirty == 0, - ("vnode_pager_generic_getpages: page %p is dirty", m)); - VM_OBJECT_WLOCK(object); - m[reqpage]->valid = VM_PAGE_BITS_ALL; - vm_pager_free_nonreq(object, m, reqpage, count, TRUE); - VM_OBJECT_WUNLOCK(object); - return (VM_PAGER_OK); - } else if (m[reqpage]->valid != 0) { - VM_OBJECT_WLOCK(object); - m[reqpage]->valid = 0; - VM_OBJECT_WUNLOCK(object); - } - - /* - * here on direct device I/O - */ - firstaddr = -1; - - /* - * calculate the run that includes the required page - */ - for (first = 0, i = 0; i < count; i = runend) { - if (vnode_pager_addr(vp, IDX_TO_OFF(m[i]->pindex), &firstaddr, - &runpg) != 0) { - relpbuf(bp, freecnt); - /* The requested page may be out of range. */ - vm_pager_free_nonreq(object, m + i, reqpage - i, - count - i, FALSE); - return (VM_PAGER_ERROR); + for (i = 0; i < count; i++) { + PCPU_INC(cnt.v_vnodein); + PCPU_INC(cnt.v_vnodepgsin); + error = vnode_pager_input_smlfs(object, m[i]); + if (error) + break; } - if (firstaddr == -1) { - VM_OBJECT_WLOCK(object); - if (i == reqpage && foff < object->un_pager.vnp.vnp_size) { - panic("vnode_pager_getpages: unexpected missing page: firstaddr: %jd, foff: 0x%jx%08jx, vnp_size: 0x%jx%08jx", - (intmax_t)firstaddr, (uintmax_t)(foff >> 32), - (uintmax_t)foff, - (uintmax_t) - (object->un_pager.vnp.vnp_size >> 32), - (uintmax_t)object->un_pager.vnp.vnp_size); - } - vm_page_lock(m[i]); - vm_page_free(m[i]); - vm_page_unlock(m[i]); - VM_OBJECT_WUNLOCK(object); - runend = i + 1; - first = runend; - continue; - } - runend = i + runpg; - if (runend <= reqpage) { - VM_OBJECT_WLOCK(object); - for (j = i; j < runend; j++) { - vm_page_lock(m[j]); - vm_page_free(m[j]); - vm_page_unlock(m[j]); - } - VM_OBJECT_WUNLOCK(object); - } else { - if (runpg < (count - first)) { - VM_OBJECT_WLOCK(object); - for (i = first + runpg; i < count; i++) { - vm_page_lock(m[i]); - vm_page_free(m[i]); - vm_page_unlock(m[i]); - } - VM_OBJECT_WUNLOCK(object); - count = first + runpg; - } - break; - } - first = runend; + return (error); } /* - * the first and last page have been calculated now, move input pages - * to be zero based... + * Truncate bytecount to vnode real size and round up physical size + * for real devices. */ - if (first != 0) { - m += first; - count -= first; - reqpage -= first; - } + if ((foff + bytecount) > object->un_pager.vnp.vnp_size) + bytecount = object->un_pager.vnp.vnp_size - foff; + secmask = bo->bo_bsize - 1; + KASSERT(secmask < PAGE_SIZE && secmask > 0, + ("%s: sector size %d too large", __func__, secmask + 1)); + bytecount = (bytecount + secmask) & ~secmask; /* - * calculate the file virtual address for the transfer - */ - foff = IDX_TO_OFF(m[0]->pindex); - - /* - * calculate the size of the transfer - */ - size = count * PAGE_SIZE; - KASSERT(count > 0, ("zero count")); - if ((foff + size) > object->un_pager.vnp.vnp_size) - size = object->un_pager.vnp.vnp_size - foff; - KASSERT(size > 0, ("zero size")); - - /* - * round up physical size for real devices. - */ - if (1) { - int secmask = bo->bo_bsize - 1; - KASSERT(secmask < PAGE_SIZE && secmask > 0, - ("vnode_pager_generic_getpages: sector size %d too large", - secmask + 1)); - size = (size + secmask) & ~secmask; - } - - /* - * and map the pages to be read into the kva, if the filesystem + * And map the pages to be read into the kva, if the filesystem * requires mapped buffers. */ if ((vp->v_mount->mnt_kern_flag & MNTK_UNMAPPED_BUFS) != 0 && @@ -978,38 +846,33 @@ vnode_pager_generic_getpages(struct vnode *vp, vm_ pmap_qenter((vm_offset_t)bp->b_data, m, count); } - /* build a minimal buffer header */ + /* Build a minimal buffer header. */ bp->b_iocmd = BIO_READ; KASSERT(bp->b_rcred == NOCRED, ("leaking read ucred")); KASSERT(bp->b_wcred == NOCRED, ("leaking write ucred")); bp->b_rcred = crhold(curthread->td_ucred); bp->b_wcred = crhold(curthread->td_ucred); - bp->b_blkno = firstaddr; + bp->b_blkno = reqblock + ((foff % bsize) / DEV_BSIZE); pbgetbo(bo, bp); bp->b_vp = vp; - bp->b_bcount = size; - bp->b_bufsize = size; - bp->b_runningbufspace = bp->b_bufsize; + bp->b_bcount = bp->b_bufsize = bp->b_runningbufspace = bytecount; for (i = 0; i < count; i++) bp->b_pages[i] = m[i]; bp->b_npages = count; - bp->b_pager.pg_reqpage = reqpage; + bp->b_iooffset = dbtob(bp->b_blkno); + atomic_add_long(&runningbufspace, bp->b_runningbufspace); - PCPU_INC(cnt.v_vnodein); PCPU_ADD(cnt.v_vnodepgsin, count); - /* do the input */ - bp->b_iooffset = dbtob(bp->b_blkno); - if (iodone != NULL) { /* async */ - bp->b_pager.pg_iodone = iodone; + bp->b_pgiodone = iodone; bp->b_caller1 = arg; bp->b_iodone = vnode_pager_generic_getpages_done_async; bp->b_flags |= B_ASYNC; BUF_KERNPROC(bp); bstrategy(bp); - /* Good bye! */ + return (VM_PAGER_OK); } else { bp->b_iodone = bdone; bstrategy(bp); @@ -1020,9 +883,8 @@ vnode_pager_generic_getpages(struct vnode *vp, vm_ bp->b_vp = NULL; pbrelbo(bp); relpbuf(bp, &vnode_pbuf_freecnt); + return (error != 0 ? VM_PAGER_ERROR : VM_PAGER_OK); } - - return (error != 0 ? VM_PAGER_ERROR : VM_PAGER_OK); } static void @@ -1031,8 +893,7 @@ vnode_pager_generic_getpages_done_async(struct buf int error; error = vnode_pager_generic_getpages_done(bp); - bp->b_pager.pg_iodone(bp->b_caller1, bp->b_pages, - bp->b_pager.pg_reqpage, error); + bp->b_pgiodone(bp->b_caller1, bp->b_pages, bp->b_npages, error); for (int i = 0; i < bp->b_npages; i++) bp->b_pages[i] = NULL; bp->b_vp = NULL; @@ -1095,9 +956,6 @@ vnode_pager_generic_getpages_done(struct buf *bp) object->un_pager.vnp.vnp_size - tfoff)) == 0, ("%s: page %p is dirty", __func__, mt)); } - - if (i != bp->b_pager.pg_reqpage) - vm_page_readahead_finish(mt); } VM_OBJECT_WUNLOCK(object); if (error != 0) Index: sys/vm/vnode_pager.h =================================================================== --- sys/vm/vnode_pager.h (revision 286413) +++ sys/vm/vnode_pager.h (working copy) @@ -41,7 +41,7 @@ #ifdef _KERNEL int vnode_pager_generic_getpages(struct vnode *vp, vm_page_t *m, - int count, int reqpage, vop_getpages_iodone_t iodone, void *arg); + int count, vop_getpages_iodone_t iodone, void *arg); int vnode_pager_generic_putpages(struct vnode *vp, vm_page_t *m, int count, boolean_t sync, int *rtvals); --sLx0z+5FKKtIVDwd--
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