Index: stable/10/sys/kern/kern_physio.c =================================================================== --- stable/10/sys/kern/kern_physio.c (revision 282567) +++ stable/10/sys/kern/kern_physio.c (revision 282568) @@ -1,170 +1,202 @@ /*- * Copyright (c) 1994 John S. Dyson * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice immediately at the beginning of the file, without modification, * this list of conditions, and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Absolutely no warranty of function or purpose is made by the author * John S. Dyson. * 4. Modifications may be freely made to this file if the above conditions * are met. */ #include __FBSDID("$FreeBSD$"); #include #include #include #include #include +#include #include #include +#include #include +#include #include +#include int physio(struct cdev *dev, struct uio *uio, int ioflag) { - struct buf *bp; - struct cdevsw *csw; + struct buf *pbuf; + struct bio *bp; + struct vm_page **pages; caddr_t sa; - u_int iolen; - int error, i, mapped; + u_int iolen, poff; + int error, i, npages, maxpages; + vm_prot_t prot; - /* Keep the process UPAGES from being swapped. XXX: why ? */ - PHOLD(curproc); - - bp = getpbuf(NULL); - sa = bp->b_data; - error = 0; - /* XXX: sanity check */ if(dev->si_iosize_max < PAGE_SIZE) { printf("WARNING: %s si_iosize_max=%d, using DFLTPHYS.\n", devtoname(dev), dev->si_iosize_max); dev->si_iosize_max = DFLTPHYS; } /* * If the driver does not want I/O to be split, that means that we * need to reject any requests that will not fit into one buffer. */ if (dev->si_flags & SI_NOSPLIT && (uio->uio_resid > dev->si_iosize_max || uio->uio_resid > MAXPHYS || uio->uio_iovcnt > 1)) { /* * Tell the user why his I/O was rejected. */ if (uio->uio_resid > dev->si_iosize_max) uprintf("%s: request size=%zd > si_iosize_max=%d; " "cannot split request\n", devtoname(dev), uio->uio_resid, dev->si_iosize_max); if (uio->uio_resid > MAXPHYS) uprintf("%s: request size=%zd > MAXPHYS=%d; " "cannot split request\n", devtoname(dev), uio->uio_resid, MAXPHYS); if (uio->uio_iovcnt > 1) uprintf("%s: request vectors=%d > 1; " "cannot split request\n", devtoname(dev), uio->uio_iovcnt); - - error = EFBIG; - goto doerror; + return (EFBIG); } + /* + * Keep the process UPAGES from being swapped. Processes swapped + * out while holding pbufs, used by swapper, may lead to deadlock. + */ + PHOLD(curproc); + + bp = g_alloc_bio(); + if (uio->uio_segflg != UIO_USERSPACE) { + pbuf = NULL; + pages = NULL; + } else if ((dev->si_flags & SI_UNMAPPED) && unmapped_buf_allowed) { + pbuf = NULL; + maxpages = btoc(MIN(uio->uio_resid, MAXPHYS)) + 1; + pages = malloc(sizeof(*pages) * maxpages, M_DEVBUF, M_WAITOK); + } else { + pbuf = getpbuf(NULL); + sa = pbuf->b_data; + maxpages = btoc(MAXPHYS); + pages = pbuf->b_pages; + } + prot = VM_PROT_READ; + if (uio->uio_rw == UIO_READ) + prot |= VM_PROT_WRITE; /* Less backwards than it looks */ + error = 0; for (i = 0; i < uio->uio_iovcnt; i++) { while (uio->uio_iov[i].iov_len) { - bp->b_flags = 0; + bzero(bp, sizeof(*bp)); if (uio->uio_rw == UIO_READ) { - bp->b_iocmd = BIO_READ; + bp->bio_cmd = BIO_READ; curthread->td_ru.ru_inblock++; } else { - bp->b_iocmd = BIO_WRITE; + bp->bio_cmd = BIO_WRITE; curthread->td_ru.ru_oublock++; } - bp->b_iodone = bdone; - bp->b_data = uio->uio_iov[i].iov_base; - bp->b_bcount = uio->uio_iov[i].iov_len; - bp->b_offset = uio->uio_offset; - bp->b_iooffset = uio->uio_offset; - bp->b_saveaddr = sa; + bp->bio_offset = uio->uio_offset; + bp->bio_data = uio->uio_iov[i].iov_base; + bp->bio_length = uio->uio_iov[i].iov_len; + if (bp->bio_length > dev->si_iosize_max) + bp->bio_length = dev->si_iosize_max; + if (bp->bio_length > MAXPHYS) + bp->bio_length = MAXPHYS; - /* Don't exceed drivers iosize limit */ - if (bp->b_bcount > dev->si_iosize_max) - bp->b_bcount = dev->si_iosize_max; - - /* - * Make sure the pbuf can map the request - * XXX: The pbuf has kvasize = MAXPHYS so a request - * XXX: larger than MAXPHYS - PAGE_SIZE must be - * XXX: page aligned or it will be fragmented. + /* + * Make sure the pbuf can map the request. + * The pbuf has kvasize = MAXPHYS, so a request + * larger than MAXPHYS - PAGE_SIZE must be + * page aligned or it will be fragmented. */ - iolen = ((vm_offset_t) bp->b_data) & PAGE_MASK; - if ((bp->b_bcount + iolen) > bp->b_kvasize) { - /* - * This device does not want I/O to be split. - */ + poff = (vm_offset_t)bp->bio_data & PAGE_MASK; + if (pbuf && bp->bio_length + poff > pbuf->b_kvasize) { if (dev->si_flags & SI_NOSPLIT) { uprintf("%s: request ptr %p is not " "on a page boundary; cannot split " "request\n", devtoname(dev), - bp->b_data); + bp->bio_data); error = EFBIG; goto doerror; } - bp->b_bcount = bp->b_kvasize; - if (iolen != 0) - bp->b_bcount -= PAGE_SIZE; + bp->bio_length = pbuf->b_kvasize; + if (poff != 0) + bp->bio_length -= PAGE_SIZE; } - bp->b_bufsize = bp->b_bcount; - bp->b_blkno = btodb(bp->b_offset); + bp->bio_bcount = bp->bio_length; + bp->bio_dev = dev; - csw = dev->si_devsw; - if (uio->uio_segflg == UIO_USERSPACE) { - if (dev->si_flags & SI_UNMAPPED) - mapped = 0; - else - mapped = 1; - if (vmapbuf(bp, mapped) < 0) { + if (pages) { + if ((npages = vm_fault_quick_hold_pages( + &curproc->p_vmspace->vm_map, + (vm_offset_t)bp->bio_data, bp->bio_length, + prot, pages, maxpages)) < 0) { error = EFAULT; goto doerror; } + if (pbuf) { + pmap_qenter((vm_offset_t)sa, + pages, npages); + bp->bio_data = sa + poff; + } else { + bp->bio_ma = pages; + bp->bio_ma_n = npages; + bp->bio_ma_offset = poff; + bp->bio_data = unmapped_buf; + bp->bio_flags |= BIO_UNMAPPED; + } } - dev_strategy_csw(dev, csw, bp); + dev->si_devsw->d_strategy(bp); if (uio->uio_rw == UIO_READ) - bwait(bp, PRIBIO, "physrd"); + biowait(bp, "physrd"); else - bwait(bp, PRIBIO, "physwr"); + biowait(bp, "physwr"); - if (uio->uio_segflg == UIO_USERSPACE) - vunmapbuf(bp); - iolen = bp->b_bcount - bp->b_resid; - if (iolen == 0 && !(bp->b_ioflags & BIO_ERROR)) + if (pages) { + if (pbuf) + pmap_qremove((vm_offset_t)sa, npages); + vm_page_unhold_pages(pages, npages); + } + + iolen = bp->bio_length - bp->bio_resid; + if (iolen == 0 && !(bp->bio_flags & BIO_ERROR)) goto doerror; /* EOF */ uio->uio_iov[i].iov_len -= iolen; uio->uio_iov[i].iov_base = (char *)uio->uio_iov[i].iov_base + iolen; uio->uio_resid -= iolen; uio->uio_offset += iolen; - if( bp->b_ioflags & BIO_ERROR) { - error = bp->b_error; + if (bp->bio_flags & BIO_ERROR) { + error = bp->bio_error; goto doerror; } } } doerror: - relpbuf(bp, NULL); + if (pbuf) + relpbuf(pbuf, NULL); + else if (pages) + free(pages, M_DEVBUF); + g_destroy_bio(bp); PRELE(curproc); return (error); } Index: stable/10 =================================================================== --- stable/10 (revision 282567) +++ stable/10 (revision 282568) Property changes on: stable/10 ___________________________________________________________________ Modified: svn:mergeinfo ## -0,0 +0,1 ## Merged /head:r281825