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mirror of https://git.FreeBSD.org/src.git synced 2024-12-24 11:29:10 +00:00
freebsd/sys/kern/subr_bus_dma.c
Colin Percival c0ada0377a Fix a bug introduced in r291716:
"The problem with the approach taken both in _bus_dmamap_load_pages and
bus_dmamap_load_ma_triv is that they split the request buffer into
arbitrary chunks based on page boundaries, creating segments that no
longer have a size that's a multiple of the sector size. This breaks
drivers like blkfront (and probably other stuff)." [1]

This was most easily triggered by running `fsck /` on a system running
in Xen (e.g. Amazon EC2) but also showed up via growfs(8) and probably
many other userland tools which access the disk directly.

Patch by:	royger [1]
"Thinks this should be fine" by:	ken
2016-01-11 20:38:39 +00:00

560 lines
14 KiB
C

/*-
* Copyright (c) 2012 EMC Corp.
* All rights reserved.
*
* Copyright (c) 1997, 1998 Justin T. Gibbs.
* 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, 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_bus.h"
#include <sys/param.h>
#include <sys/conf.h>
#include <sys/systm.h>
#include <sys/bio.h>
#include <sys/bus.h>
#include <sys/callout.h>
#include <sys/mbuf.h>
#include <sys/memdesc.h>
#include <sys/proc.h>
#include <sys/uio.h>
#include <vm/vm.h>
#include <vm/vm_page.h>
#include <vm/vm_map.h>
#include <vm/pmap.h>
#include <cam/cam.h>
#include <cam/cam_ccb.h>
#include <machine/bus.h>
/*
* Load up data starting at offset within a region specified by a
* list of virtual address ranges until either length or the region
* are exhausted.
*/
static int
_bus_dmamap_load_vlist(bus_dma_tag_t dmat, bus_dmamap_t map,
bus_dma_segment_t *list, int sglist_cnt, struct pmap *pmap, int *nsegs,
int flags, size_t offset, size_t length)
{
int error;
error = 0;
for (; sglist_cnt > 0 && length != 0; sglist_cnt--, list++) {
char *addr;
size_t ds_len;
KASSERT((offset < list->ds_len),
("Invalid mid-segment offset"));
addr = (char *)(uintptr_t)list->ds_addr + offset;
ds_len = list->ds_len - offset;
offset = 0;
if (ds_len > length)
ds_len = length;
length -= ds_len;
KASSERT((ds_len != 0), ("Segment length is zero"));
error = _bus_dmamap_load_buffer(dmat, map, addr, ds_len, pmap,
flags, NULL, nsegs);
if (error)
break;
}
return (error);
}
/*
* Load a list of physical addresses.
*/
static int
_bus_dmamap_load_plist(bus_dma_tag_t dmat, bus_dmamap_t map,
bus_dma_segment_t *list, int sglist_cnt, int *nsegs, int flags)
{
int error;
error = 0;
for (; sglist_cnt > 0; sglist_cnt--, list++) {
error = _bus_dmamap_load_phys(dmat, map,
(vm_paddr_t)list->ds_addr, list->ds_len, flags, NULL,
nsegs);
if (error)
break;
}
return (error);
}
/*
* Load an mbuf chain.
*/
static int
_bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map,
struct mbuf *m0, bus_dma_segment_t *segs, int *nsegs, int flags)
{
struct mbuf *m;
int error;
error = 0;
for (m = m0; m != NULL && error == 0; m = m->m_next) {
if (m->m_len > 0) {
error = _bus_dmamap_load_buffer(dmat, map, m->m_data,
m->m_len, kernel_pmap, flags | BUS_DMA_LOAD_MBUF,
segs, nsegs);
}
}
CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
__func__, dmat, flags, error, *nsegs);
return (error);
}
/*
* Load from block io.
*/
static int
_bus_dmamap_load_bio(bus_dma_tag_t dmat, bus_dmamap_t map, struct bio *bio,
int *nsegs, int flags)
{
if ((bio->bio_flags & BIO_VLIST) != 0) {
bus_dma_segment_t *segs = (bus_dma_segment_t *)bio->bio_data;
return (_bus_dmamap_load_vlist(dmat, map, segs, bio->bio_ma_n,
kernel_pmap, nsegs, flags, bio->bio_ma_offset,
bio->bio_bcount));
}
if ((bio->bio_flags & BIO_UNMAPPED) != 0)
return (_bus_dmamap_load_ma(dmat, map, bio->bio_ma,
bio->bio_bcount, bio->bio_ma_offset, flags, NULL, nsegs));
return (_bus_dmamap_load_buffer(dmat, map, bio->bio_data,
bio->bio_bcount, kernel_pmap, flags, NULL, nsegs));
}
int
bus_dmamap_load_ma_triv(bus_dma_tag_t dmat, bus_dmamap_t map,
struct vm_page **ma, bus_size_t tlen, int ma_offs, int flags,
bus_dma_segment_t *segs, int *segp)
{
vm_paddr_t paddr;
bus_size_t len;
int error, i;
error = 0;
for (i = 0; tlen > 0; i++, tlen -= len) {
len = min(PAGE_SIZE - ma_offs, tlen);
paddr = VM_PAGE_TO_PHYS(ma[i]) + ma_offs;
error = _bus_dmamap_load_phys(dmat, map, paddr, len,
flags, segs, segp);
if (error != 0)
break;
ma_offs = 0;
}
return (error);
}
/*
* Load a cam control block.
*/
static int
_bus_dmamap_load_ccb(bus_dma_tag_t dmat, bus_dmamap_t map, union ccb *ccb,
int *nsegs, int flags)
{
struct ccb_hdr *ccb_h;
void *data_ptr;
int error;
uint32_t dxfer_len;
uint16_t sglist_cnt;
error = 0;
ccb_h = &ccb->ccb_h;
switch (ccb_h->func_code) {
case XPT_SCSI_IO: {
struct ccb_scsiio *csio;
csio = &ccb->csio;
data_ptr = csio->data_ptr;
dxfer_len = csio->dxfer_len;
sglist_cnt = csio->sglist_cnt;
break;
}
case XPT_CONT_TARGET_IO: {
struct ccb_scsiio *ctio;
ctio = &ccb->ctio;
data_ptr = ctio->data_ptr;
dxfer_len = ctio->dxfer_len;
sglist_cnt = ctio->sglist_cnt;
break;
}
case XPT_ATA_IO: {
struct ccb_ataio *ataio;
ataio = &ccb->ataio;
data_ptr = ataio->data_ptr;
dxfer_len = ataio->dxfer_len;
sglist_cnt = 0;
break;
}
default:
panic("_bus_dmamap_load_ccb: Unsupported func code %d",
ccb_h->func_code);
}
switch ((ccb_h->flags & CAM_DATA_MASK)) {
case CAM_DATA_VADDR:
error = _bus_dmamap_load_buffer(dmat, map, data_ptr, dxfer_len,
kernel_pmap, flags, NULL, nsegs);
break;
case CAM_DATA_PADDR:
error = _bus_dmamap_load_phys(dmat, map,
(vm_paddr_t)(uintptr_t)data_ptr, dxfer_len, flags, NULL,
nsegs);
break;
case CAM_DATA_SG:
error = _bus_dmamap_load_vlist(dmat, map,
(bus_dma_segment_t *)data_ptr, sglist_cnt, kernel_pmap,
nsegs, flags, 0, dxfer_len);
break;
case CAM_DATA_SG_PADDR:
error = _bus_dmamap_load_plist(dmat, map,
(bus_dma_segment_t *)data_ptr, sglist_cnt, nsegs, flags);
break;
case CAM_DATA_BIO:
error = _bus_dmamap_load_bio(dmat, map, (struct bio *)data_ptr,
nsegs, flags);
break;
default:
panic("_bus_dmamap_load_ccb: flags 0x%X unimplemented",
ccb_h->flags);
}
return (error);
}
/*
* Load a uio.
*/
static int
_bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map, struct uio *uio,
int *nsegs, int flags)
{
bus_size_t resid;
bus_size_t minlen;
struct iovec *iov;
pmap_t pmap;
caddr_t addr;
int error, i;
if (uio->uio_segflg == UIO_USERSPACE) {
KASSERT(uio->uio_td != NULL,
("bus_dmamap_load_uio: USERSPACE but no proc"));
pmap = vmspace_pmap(uio->uio_td->td_proc->p_vmspace);
} else
pmap = kernel_pmap;
resid = uio->uio_resid;
iov = uio->uio_iov;
error = 0;
for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) {
/*
* Now at the first iovec to load. Load each iovec
* until we have exhausted the residual count.
*/
addr = (caddr_t) iov[i].iov_base;
minlen = resid < iov[i].iov_len ? resid : iov[i].iov_len;
if (minlen > 0) {
error = _bus_dmamap_load_buffer(dmat, map, addr,
minlen, pmap, flags, NULL, nsegs);
resid -= minlen;
}
}
return (error);
}
/*
* Map the buffer buf into bus space using the dmamap map.
*/
int
bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
bus_size_t buflen, bus_dmamap_callback_t *callback,
void *callback_arg, int flags)
{
bus_dma_segment_t *segs;
struct memdesc mem;
int error;
int nsegs;
if ((flags & BUS_DMA_NOWAIT) == 0) {
mem = memdesc_vaddr(buf, buflen);
_bus_dmamap_waitok(dmat, map, &mem, callback, callback_arg);
}
nsegs = -1;
error = _bus_dmamap_load_buffer(dmat, map, buf, buflen, kernel_pmap,
flags, NULL, &nsegs);
nsegs++;
CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
__func__, dmat, flags, error, nsegs);
if (error == EINPROGRESS)
return (error);
segs = _bus_dmamap_complete(dmat, map, NULL, nsegs, error);
if (error)
(*callback)(callback_arg, segs, 0, error);
else
(*callback)(callback_arg, segs, nsegs, 0);
/*
* Return ENOMEM to the caller so that it can pass it up the stack.
* This error only happens when NOWAIT is set, so deferral is disabled.
*/
if (error == ENOMEM)
return (error);
return (0);
}
int
bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map, struct mbuf *m0,
bus_dmamap_callback2_t *callback, void *callback_arg, int flags)
{
bus_dma_segment_t *segs;
int nsegs, error;
M_ASSERTPKTHDR(m0);
flags |= BUS_DMA_NOWAIT;
nsegs = -1;
error = _bus_dmamap_load_mbuf_sg(dmat, map, m0, NULL, &nsegs, flags);
++nsegs;
segs = _bus_dmamap_complete(dmat, map, NULL, nsegs, error);
if (error)
(*callback)(callback_arg, segs, 0, 0, error);
else
(*callback)(callback_arg, segs, nsegs, m0->m_pkthdr.len, error);
CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
__func__, dmat, flags, error, nsegs);
return (error);
}
int
bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map, struct mbuf *m0,
bus_dma_segment_t *segs, int *nsegs, int flags)
{
int error;
flags |= BUS_DMA_NOWAIT;
*nsegs = -1;
error = _bus_dmamap_load_mbuf_sg(dmat, map, m0, segs, nsegs, flags);
++*nsegs;
_bus_dmamap_complete(dmat, map, segs, *nsegs, error);
return (error);
}
int
bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map, struct uio *uio,
bus_dmamap_callback2_t *callback, void *callback_arg, int flags)
{
bus_dma_segment_t *segs;
int nsegs, error;
flags |= BUS_DMA_NOWAIT;
nsegs = -1;
error = _bus_dmamap_load_uio(dmat, map, uio, &nsegs, flags);
nsegs++;
segs = _bus_dmamap_complete(dmat, map, NULL, nsegs, error);
if (error)
(*callback)(callback_arg, segs, 0, 0, error);
else
(*callback)(callback_arg, segs, nsegs, uio->uio_resid, error);
CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
__func__, dmat, flags, error, nsegs);
return (error);
}
int
bus_dmamap_load_ccb(bus_dma_tag_t dmat, bus_dmamap_t map, union ccb *ccb,
bus_dmamap_callback_t *callback, void *callback_arg,
int flags)
{
bus_dma_segment_t *segs;
struct ccb_hdr *ccb_h;
struct memdesc mem;
int error;
int nsegs;
ccb_h = &ccb->ccb_h;
if ((ccb_h->flags & CAM_DIR_MASK) == CAM_DIR_NONE) {
callback(callback_arg, NULL, 0, 0);
return (0);
}
if ((flags & BUS_DMA_NOWAIT) == 0) {
mem = memdesc_ccb(ccb);
_bus_dmamap_waitok(dmat, map, &mem, callback, callback_arg);
}
nsegs = -1;
error = _bus_dmamap_load_ccb(dmat, map, ccb, &nsegs, flags);
nsegs++;
CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
__func__, dmat, flags, error, nsegs);
if (error == EINPROGRESS)
return (error);
segs = _bus_dmamap_complete(dmat, map, NULL, nsegs, error);
if (error)
(*callback)(callback_arg, segs, 0, error);
else
(*callback)(callback_arg, segs, nsegs, error);
/*
* Return ENOMEM to the caller so that it can pass it up the stack.
* This error only happens when NOWAIT is set, so deferral is disabled.
*/
if (error == ENOMEM)
return (error);
return (0);
}
int
bus_dmamap_load_bio(bus_dma_tag_t dmat, bus_dmamap_t map, struct bio *bio,
bus_dmamap_callback_t *callback, void *callback_arg,
int flags)
{
bus_dma_segment_t *segs;
struct memdesc mem;
int error;
int nsegs;
if ((flags & BUS_DMA_NOWAIT) == 0) {
mem = memdesc_bio(bio);
_bus_dmamap_waitok(dmat, map, &mem, callback, callback_arg);
}
nsegs = -1;
error = _bus_dmamap_load_bio(dmat, map, bio, &nsegs, flags);
nsegs++;
CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
__func__, dmat, flags, error, nsegs);
if (error == EINPROGRESS)
return (error);
segs = _bus_dmamap_complete(dmat, map, NULL, nsegs, error);
if (error)
(*callback)(callback_arg, segs, 0, error);
else
(*callback)(callback_arg, segs, nsegs, error);
/*
* Return ENOMEM to the caller so that it can pass it up the stack.
* This error only happens when NOWAIT is set, so deferral is disabled.
*/
if (error == ENOMEM)
return (error);
return (0);
}
int
bus_dmamap_load_mem(bus_dma_tag_t dmat, bus_dmamap_t map,
struct memdesc *mem, bus_dmamap_callback_t *callback,
void *callback_arg, int flags)
{
bus_dma_segment_t *segs;
int error;
int nsegs;
if ((flags & BUS_DMA_NOWAIT) == 0)
_bus_dmamap_waitok(dmat, map, mem, callback, callback_arg);
nsegs = -1;
error = 0;
switch (mem->md_type) {
case MEMDESC_VADDR:
error = _bus_dmamap_load_buffer(dmat, map, mem->u.md_vaddr,
mem->md_opaque, kernel_pmap, flags, NULL, &nsegs);
break;
case MEMDESC_PADDR:
error = _bus_dmamap_load_phys(dmat, map, mem->u.md_paddr,
mem->md_opaque, flags, NULL, &nsegs);
break;
case MEMDESC_VLIST:
error = _bus_dmamap_load_vlist(dmat, map, mem->u.md_list,
mem->md_opaque, kernel_pmap, &nsegs, flags, 0, SIZE_T_MAX);
break;
case MEMDESC_PLIST:
error = _bus_dmamap_load_plist(dmat, map, mem->u.md_list,
mem->md_opaque, &nsegs, flags);
break;
case MEMDESC_BIO:
error = _bus_dmamap_load_bio(dmat, map, mem->u.md_bio,
&nsegs, flags);
break;
case MEMDESC_UIO:
error = _bus_dmamap_load_uio(dmat, map, mem->u.md_uio,
&nsegs, flags);
break;
case MEMDESC_MBUF:
error = _bus_dmamap_load_mbuf_sg(dmat, map, mem->u.md_mbuf,
NULL, &nsegs, flags);
break;
case MEMDESC_CCB:
error = _bus_dmamap_load_ccb(dmat, map, mem->u.md_ccb, &nsegs,
flags);
break;
}
nsegs++;
CTR5(KTR_BUSDMA, "%s: tag %p tag flags 0x%x error %d nsegs %d",
__func__, dmat, flags, error, nsegs);
if (error == EINPROGRESS)
return (error);
segs = _bus_dmamap_complete(dmat, map, NULL, nsegs, error);
if (error)
(*callback)(callback_arg, segs, 0, error);
else
(*callback)(callback_arg, segs, nsegs, 0);
/*
* Return ENOMEM to the caller so that it can pass it up the stack.
* This error only happens when NOWAIT is set, so deferral is disabled.
*/
if (error == ENOMEM)
return (error);
return (0);
}