mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-12 05:48:40 +00:00
![Eric Farman](/assets/img/avatar_default.png)
We have two nested loops to check the entries within the pfn_array_table arrays. But we mistakenly use the outer array as an index in our check, and completely ignore the indexing performed by the inner loop. Cc: stable@vger.kernel.org Signed-off-by: Eric Farman <farman@linux.ibm.com> Message-Id: <20181002010235.42483-1-farman@linux.ibm.com> Signed-off-by: Cornelia Huck <cohuck@redhat.com>
878 lines
21 KiB
C
878 lines
21 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* channel program interfaces
|
|
*
|
|
* Copyright IBM Corp. 2017
|
|
*
|
|
* Author(s): Dong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
|
|
* Xiao Feng Ren <renxiaof@linux.vnet.ibm.com>
|
|
*/
|
|
|
|
#include <linux/mm.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/iommu.h>
|
|
#include <linux/vfio.h>
|
|
#include <asm/idals.h>
|
|
|
|
#include "vfio_ccw_cp.h"
|
|
|
|
/*
|
|
* Max length for ccw chain.
|
|
* XXX: Limit to 256, need to check more?
|
|
*/
|
|
#define CCWCHAIN_LEN_MAX 256
|
|
|
|
struct pfn_array {
|
|
/* Starting guest physical I/O address. */
|
|
unsigned long pa_iova;
|
|
/* Array that stores PFNs of the pages need to pin. */
|
|
unsigned long *pa_iova_pfn;
|
|
/* Array that receives PFNs of the pages pinned. */
|
|
unsigned long *pa_pfn;
|
|
/* Number of pages pinned from @pa_iova. */
|
|
int pa_nr;
|
|
};
|
|
|
|
struct pfn_array_table {
|
|
struct pfn_array *pat_pa;
|
|
int pat_nr;
|
|
};
|
|
|
|
struct ccwchain {
|
|
struct list_head next;
|
|
struct ccw1 *ch_ccw;
|
|
/* Guest physical address of the current chain. */
|
|
u64 ch_iova;
|
|
/* Count of the valid ccws in chain. */
|
|
int ch_len;
|
|
/* Pinned PAGEs for the original data. */
|
|
struct pfn_array_table *ch_pat;
|
|
};
|
|
|
|
/*
|
|
* pfn_array_alloc_pin() - alloc memory for PFNs, then pin user pages in memory
|
|
* @pa: pfn_array on which to perform the operation
|
|
* @mdev: the mediated device to perform pin/unpin operations
|
|
* @iova: target guest physical address
|
|
* @len: number of bytes that should be pinned from @iova
|
|
*
|
|
* Attempt to allocate memory for PFNs, and pin user pages in memory.
|
|
*
|
|
* Usage of pfn_array:
|
|
* We expect (pa_nr == 0) and (pa_iova_pfn == NULL), any field in
|
|
* this structure will be filled in by this function.
|
|
*
|
|
* Returns:
|
|
* Number of pages pinned on success.
|
|
* If @pa->pa_nr is not 0, or @pa->pa_iova_pfn is not NULL initially,
|
|
* returns -EINVAL.
|
|
* If no pages were pinned, returns -errno.
|
|
*/
|
|
static int pfn_array_alloc_pin(struct pfn_array *pa, struct device *mdev,
|
|
u64 iova, unsigned int len)
|
|
{
|
|
int i, ret = 0;
|
|
|
|
if (!len)
|
|
return 0;
|
|
|
|
if (pa->pa_nr || pa->pa_iova_pfn)
|
|
return -EINVAL;
|
|
|
|
pa->pa_iova = iova;
|
|
|
|
pa->pa_nr = ((iova & ~PAGE_MASK) + len + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
|
|
if (!pa->pa_nr)
|
|
return -EINVAL;
|
|
|
|
pa->pa_iova_pfn = kcalloc(pa->pa_nr,
|
|
sizeof(*pa->pa_iova_pfn) +
|
|
sizeof(*pa->pa_pfn),
|
|
GFP_KERNEL);
|
|
if (unlikely(!pa->pa_iova_pfn))
|
|
return -ENOMEM;
|
|
pa->pa_pfn = pa->pa_iova_pfn + pa->pa_nr;
|
|
|
|
pa->pa_iova_pfn[0] = pa->pa_iova >> PAGE_SHIFT;
|
|
for (i = 1; i < pa->pa_nr; i++)
|
|
pa->pa_iova_pfn[i] = pa->pa_iova_pfn[i - 1] + 1;
|
|
|
|
ret = vfio_pin_pages(mdev, pa->pa_iova_pfn, pa->pa_nr,
|
|
IOMMU_READ | IOMMU_WRITE, pa->pa_pfn);
|
|
|
|
if (ret < 0) {
|
|
goto err_out;
|
|
} else if (ret > 0 && ret != pa->pa_nr) {
|
|
vfio_unpin_pages(mdev, pa->pa_iova_pfn, ret);
|
|
ret = -EINVAL;
|
|
goto err_out;
|
|
}
|
|
|
|
return ret;
|
|
|
|
err_out:
|
|
pa->pa_nr = 0;
|
|
kfree(pa->pa_iova_pfn);
|
|
pa->pa_iova_pfn = NULL;
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* Unpin the pages before releasing the memory. */
|
|
static void pfn_array_unpin_free(struct pfn_array *pa, struct device *mdev)
|
|
{
|
|
vfio_unpin_pages(mdev, pa->pa_iova_pfn, pa->pa_nr);
|
|
pa->pa_nr = 0;
|
|
kfree(pa->pa_iova_pfn);
|
|
}
|
|
|
|
static int pfn_array_table_init(struct pfn_array_table *pat, int nr)
|
|
{
|
|
pat->pat_pa = kcalloc(nr, sizeof(*pat->pat_pa), GFP_KERNEL);
|
|
if (unlikely(ZERO_OR_NULL_PTR(pat->pat_pa))) {
|
|
pat->pat_nr = 0;
|
|
return -ENOMEM;
|
|
}
|
|
|
|
pat->pat_nr = nr;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void pfn_array_table_unpin_free(struct pfn_array_table *pat,
|
|
struct device *mdev)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < pat->pat_nr; i++)
|
|
pfn_array_unpin_free(pat->pat_pa + i, mdev);
|
|
|
|
if (pat->pat_nr) {
|
|
kfree(pat->pat_pa);
|
|
pat->pat_pa = NULL;
|
|
pat->pat_nr = 0;
|
|
}
|
|
}
|
|
|
|
static bool pfn_array_table_iova_pinned(struct pfn_array_table *pat,
|
|
unsigned long iova)
|
|
{
|
|
struct pfn_array *pa = pat->pat_pa;
|
|
unsigned long iova_pfn = iova >> PAGE_SHIFT;
|
|
int i, j;
|
|
|
|
for (i = 0; i < pat->pat_nr; i++, pa++)
|
|
for (j = 0; j < pa->pa_nr; j++)
|
|
if (pa->pa_iova_pfn[j] == iova_pfn)
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
/* Create the list idal words for a pfn_array_table. */
|
|
static inline void pfn_array_table_idal_create_words(
|
|
struct pfn_array_table *pat,
|
|
unsigned long *idaws)
|
|
{
|
|
struct pfn_array *pa;
|
|
int i, j, k;
|
|
|
|
/*
|
|
* Idal words (execept the first one) rely on the memory being 4k
|
|
* aligned. If a user virtual address is 4K aligned, then it's
|
|
* corresponding kernel physical address will also be 4K aligned. Thus
|
|
* there will be no problem here to simply use the phys to create an
|
|
* idaw.
|
|
*/
|
|
k = 0;
|
|
for (i = 0; i < pat->pat_nr; i++) {
|
|
pa = pat->pat_pa + i;
|
|
for (j = 0; j < pa->pa_nr; j++) {
|
|
idaws[k] = pa->pa_pfn[j] << PAGE_SHIFT;
|
|
if (k == 0)
|
|
idaws[k] += pa->pa_iova & (PAGE_SIZE - 1);
|
|
k++;
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* Within the domain (@mdev), copy @n bytes from a guest physical
|
|
* address (@iova) to a host physical address (@to).
|
|
*/
|
|
static long copy_from_iova(struct device *mdev,
|
|
void *to, u64 iova,
|
|
unsigned long n)
|
|
{
|
|
struct pfn_array pa = {0};
|
|
u64 from;
|
|
int i, ret;
|
|
unsigned long l, m;
|
|
|
|
ret = pfn_array_alloc_pin(&pa, mdev, iova, n);
|
|
if (ret <= 0)
|
|
return ret;
|
|
|
|
l = n;
|
|
for (i = 0; i < pa.pa_nr; i++) {
|
|
from = pa.pa_pfn[i] << PAGE_SHIFT;
|
|
m = PAGE_SIZE;
|
|
if (i == 0) {
|
|
from += iova & (PAGE_SIZE - 1);
|
|
m -= iova & (PAGE_SIZE - 1);
|
|
}
|
|
|
|
m = min(l, m);
|
|
memcpy(to + (n - l), (void *)from, m);
|
|
|
|
l -= m;
|
|
if (l == 0)
|
|
break;
|
|
}
|
|
|
|
pfn_array_unpin_free(&pa, mdev);
|
|
|
|
return l;
|
|
}
|
|
|
|
static long copy_ccw_from_iova(struct channel_program *cp,
|
|
struct ccw1 *to, u64 iova,
|
|
unsigned long len)
|
|
{
|
|
struct ccw0 ccw0;
|
|
struct ccw1 *pccw1;
|
|
int ret;
|
|
int i;
|
|
|
|
ret = copy_from_iova(cp->mdev, to, iova, len * sizeof(struct ccw1));
|
|
if (ret)
|
|
return ret;
|
|
|
|
if (!cp->orb.cmd.fmt) {
|
|
pccw1 = to;
|
|
for (i = 0; i < len; i++) {
|
|
ccw0 = *(struct ccw0 *)pccw1;
|
|
if ((pccw1->cmd_code & 0x0f) == CCW_CMD_TIC) {
|
|
pccw1->cmd_code = CCW_CMD_TIC;
|
|
pccw1->flags = 0;
|
|
pccw1->count = 0;
|
|
} else {
|
|
pccw1->cmd_code = ccw0.cmd_code;
|
|
pccw1->flags = ccw0.flags;
|
|
pccw1->count = ccw0.count;
|
|
}
|
|
pccw1->cda = ccw0.cda;
|
|
pccw1++;
|
|
}
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Helpers to operate ccwchain.
|
|
*/
|
|
#define ccw_is_test(_ccw) (((_ccw)->cmd_code & 0x0F) == 0)
|
|
|
|
#define ccw_is_noop(_ccw) ((_ccw)->cmd_code == CCW_CMD_NOOP)
|
|
|
|
#define ccw_is_tic(_ccw) ((_ccw)->cmd_code == CCW_CMD_TIC)
|
|
|
|
#define ccw_is_idal(_ccw) ((_ccw)->flags & CCW_FLAG_IDA)
|
|
|
|
|
|
#define ccw_is_chain(_ccw) ((_ccw)->flags & (CCW_FLAG_CC | CCW_FLAG_DC))
|
|
|
|
static struct ccwchain *ccwchain_alloc(struct channel_program *cp, int len)
|
|
{
|
|
struct ccwchain *chain;
|
|
void *data;
|
|
size_t size;
|
|
|
|
/* Make ccw address aligned to 8. */
|
|
size = ((sizeof(*chain) + 7L) & -8L) +
|
|
sizeof(*chain->ch_ccw) * len +
|
|
sizeof(*chain->ch_pat) * len;
|
|
chain = kzalloc(size, GFP_DMA | GFP_KERNEL);
|
|
if (!chain)
|
|
return NULL;
|
|
|
|
data = (u8 *)chain + ((sizeof(*chain) + 7L) & -8L);
|
|
chain->ch_ccw = (struct ccw1 *)data;
|
|
|
|
data = (u8 *)(chain->ch_ccw) + sizeof(*chain->ch_ccw) * len;
|
|
chain->ch_pat = (struct pfn_array_table *)data;
|
|
|
|
chain->ch_len = len;
|
|
|
|
list_add_tail(&chain->next, &cp->ccwchain_list);
|
|
|
|
return chain;
|
|
}
|
|
|
|
static void ccwchain_free(struct ccwchain *chain)
|
|
{
|
|
list_del(&chain->next);
|
|
kfree(chain);
|
|
}
|
|
|
|
/* Free resource for a ccw that allocated memory for its cda. */
|
|
static void ccwchain_cda_free(struct ccwchain *chain, int idx)
|
|
{
|
|
struct ccw1 *ccw = chain->ch_ccw + idx;
|
|
|
|
if (ccw_is_test(ccw) || ccw_is_noop(ccw) || ccw_is_tic(ccw))
|
|
return;
|
|
if (!ccw->count)
|
|
return;
|
|
|
|
kfree((void *)(u64)ccw->cda);
|
|
}
|
|
|
|
/* Unpin the pages then free the memory resources. */
|
|
static void cp_unpin_free(struct channel_program *cp)
|
|
{
|
|
struct ccwchain *chain, *temp;
|
|
int i;
|
|
|
|
list_for_each_entry_safe(chain, temp, &cp->ccwchain_list, next) {
|
|
for (i = 0; i < chain->ch_len; i++) {
|
|
pfn_array_table_unpin_free(chain->ch_pat + i,
|
|
cp->mdev);
|
|
ccwchain_cda_free(chain, i);
|
|
}
|
|
ccwchain_free(chain);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* ccwchain_calc_length - calculate the length of the ccw chain.
|
|
* @iova: guest physical address of the target ccw chain
|
|
* @cp: channel_program on which to perform the operation
|
|
*
|
|
* This is the chain length not considering any TICs.
|
|
* You need to do a new round for each TIC target.
|
|
*
|
|
* The program is also validated for absence of not yet supported
|
|
* indirect data addressing scenarios.
|
|
*
|
|
* Returns: the length of the ccw chain or -errno.
|
|
*/
|
|
static int ccwchain_calc_length(u64 iova, struct channel_program *cp)
|
|
{
|
|
struct ccw1 *ccw, *p;
|
|
int cnt;
|
|
|
|
/*
|
|
* Copy current chain from guest to host kernel.
|
|
* Currently the chain length is limited to CCWCHAIN_LEN_MAX (256).
|
|
* So copying 2K is enough (safe).
|
|
*/
|
|
p = ccw = kcalloc(CCWCHAIN_LEN_MAX, sizeof(*ccw), GFP_KERNEL);
|
|
if (!ccw)
|
|
return -ENOMEM;
|
|
|
|
cnt = copy_ccw_from_iova(cp, ccw, iova, CCWCHAIN_LEN_MAX);
|
|
if (cnt) {
|
|
kfree(ccw);
|
|
return cnt;
|
|
}
|
|
|
|
cnt = 0;
|
|
do {
|
|
cnt++;
|
|
|
|
/*
|
|
* As we don't want to fail direct addressing even if the
|
|
* orb specified one of the unsupported formats, we defer
|
|
* checking for IDAWs in unsupported formats to here.
|
|
*/
|
|
if ((!cp->orb.cmd.c64 || cp->orb.cmd.i2k) && ccw_is_idal(ccw))
|
|
return -EOPNOTSUPP;
|
|
|
|
if ((!ccw_is_chain(ccw)) && (!ccw_is_tic(ccw)))
|
|
break;
|
|
|
|
ccw++;
|
|
} while (cnt < CCWCHAIN_LEN_MAX + 1);
|
|
|
|
if (cnt == CCWCHAIN_LEN_MAX + 1)
|
|
cnt = -EINVAL;
|
|
|
|
kfree(p);
|
|
return cnt;
|
|
}
|
|
|
|
static int tic_target_chain_exists(struct ccw1 *tic, struct channel_program *cp)
|
|
{
|
|
struct ccwchain *chain;
|
|
u32 ccw_head, ccw_tail;
|
|
|
|
list_for_each_entry(chain, &cp->ccwchain_list, next) {
|
|
ccw_head = chain->ch_iova;
|
|
ccw_tail = ccw_head + (chain->ch_len - 1) * sizeof(struct ccw1);
|
|
|
|
if ((ccw_head <= tic->cda) && (tic->cda <= ccw_tail))
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ccwchain_loop_tic(struct ccwchain *chain,
|
|
struct channel_program *cp);
|
|
|
|
static int ccwchain_handle_tic(struct ccw1 *tic, struct channel_program *cp)
|
|
{
|
|
struct ccwchain *chain;
|
|
int len, ret;
|
|
|
|
/* May transfer to an existing chain. */
|
|
if (tic_target_chain_exists(tic, cp))
|
|
return 0;
|
|
|
|
/* Get chain length. */
|
|
len = ccwchain_calc_length(tic->cda, cp);
|
|
if (len < 0)
|
|
return len;
|
|
|
|
/* Need alloc a new chain for this one. */
|
|
chain = ccwchain_alloc(cp, len);
|
|
if (!chain)
|
|
return -ENOMEM;
|
|
chain->ch_iova = tic->cda;
|
|
|
|
/* Copy the new chain from user. */
|
|
ret = copy_ccw_from_iova(cp, chain->ch_ccw, tic->cda, len);
|
|
if (ret) {
|
|
ccwchain_free(chain);
|
|
return ret;
|
|
}
|
|
|
|
/* Loop for tics on this new chain. */
|
|
return ccwchain_loop_tic(chain, cp);
|
|
}
|
|
|
|
/* Loop for TICs. */
|
|
static int ccwchain_loop_tic(struct ccwchain *chain, struct channel_program *cp)
|
|
{
|
|
struct ccw1 *tic;
|
|
int i, ret;
|
|
|
|
for (i = 0; i < chain->ch_len; i++) {
|
|
tic = chain->ch_ccw + i;
|
|
|
|
if (!ccw_is_tic(tic))
|
|
continue;
|
|
|
|
ret = ccwchain_handle_tic(tic, cp);
|
|
if (ret)
|
|
return ret;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int ccwchain_fetch_tic(struct ccwchain *chain,
|
|
int idx,
|
|
struct channel_program *cp)
|
|
{
|
|
struct ccw1 *ccw = chain->ch_ccw + idx;
|
|
struct ccwchain *iter;
|
|
u32 ccw_head, ccw_tail;
|
|
|
|
list_for_each_entry(iter, &cp->ccwchain_list, next) {
|
|
ccw_head = iter->ch_iova;
|
|
ccw_tail = ccw_head + (iter->ch_len - 1) * sizeof(struct ccw1);
|
|
|
|
if ((ccw_head <= ccw->cda) && (ccw->cda <= ccw_tail)) {
|
|
ccw->cda = (__u32) (addr_t) (((char *)iter->ch_ccw) +
|
|
(ccw->cda - ccw_head));
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
return -EFAULT;
|
|
}
|
|
|
|
static int ccwchain_fetch_direct(struct ccwchain *chain,
|
|
int idx,
|
|
struct channel_program *cp)
|
|
{
|
|
struct ccw1 *ccw;
|
|
struct pfn_array_table *pat;
|
|
unsigned long *idaws;
|
|
int ret;
|
|
|
|
ccw = chain->ch_ccw + idx;
|
|
|
|
if (!ccw->count) {
|
|
/*
|
|
* We just want the translation result of any direct ccw
|
|
* to be an IDA ccw, so let's add the IDA flag for it.
|
|
* Although the flag will be ignored by firmware.
|
|
*/
|
|
ccw->flags |= CCW_FLAG_IDA;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Pin data page(s) in memory.
|
|
* The number of pages actually is the count of the idaws which will be
|
|
* needed when translating a direct ccw to a idal ccw.
|
|
*/
|
|
pat = chain->ch_pat + idx;
|
|
ret = pfn_array_table_init(pat, 1);
|
|
if (ret)
|
|
goto out_init;
|
|
|
|
ret = pfn_array_alloc_pin(pat->pat_pa, cp->mdev, ccw->cda, ccw->count);
|
|
if (ret < 0)
|
|
goto out_init;
|
|
|
|
/* Translate this direct ccw to a idal ccw. */
|
|
idaws = kcalloc(ret, sizeof(*idaws), GFP_DMA | GFP_KERNEL);
|
|
if (!idaws) {
|
|
ret = -ENOMEM;
|
|
goto out_unpin;
|
|
}
|
|
ccw->cda = (__u32) virt_to_phys(idaws);
|
|
ccw->flags |= CCW_FLAG_IDA;
|
|
|
|
pfn_array_table_idal_create_words(pat, idaws);
|
|
|
|
return 0;
|
|
|
|
out_unpin:
|
|
pfn_array_table_unpin_free(pat, cp->mdev);
|
|
out_init:
|
|
ccw->cda = 0;
|
|
return ret;
|
|
}
|
|
|
|
static int ccwchain_fetch_idal(struct ccwchain *chain,
|
|
int idx,
|
|
struct channel_program *cp)
|
|
{
|
|
struct ccw1 *ccw;
|
|
struct pfn_array_table *pat;
|
|
unsigned long *idaws;
|
|
u64 idaw_iova;
|
|
unsigned int idaw_nr, idaw_len;
|
|
int i, ret;
|
|
|
|
ccw = chain->ch_ccw + idx;
|
|
|
|
if (!ccw->count)
|
|
return 0;
|
|
|
|
/* Calculate size of idaws. */
|
|
ret = copy_from_iova(cp->mdev, &idaw_iova, ccw->cda, sizeof(idaw_iova));
|
|
if (ret)
|
|
return ret;
|
|
idaw_nr = idal_nr_words((void *)(idaw_iova), ccw->count);
|
|
idaw_len = idaw_nr * sizeof(*idaws);
|
|
|
|
/* Pin data page(s) in memory. */
|
|
pat = chain->ch_pat + idx;
|
|
ret = pfn_array_table_init(pat, idaw_nr);
|
|
if (ret)
|
|
goto out_init;
|
|
|
|
/* Translate idal ccw to use new allocated idaws. */
|
|
idaws = kzalloc(idaw_len, GFP_DMA | GFP_KERNEL);
|
|
if (!idaws) {
|
|
ret = -ENOMEM;
|
|
goto out_unpin;
|
|
}
|
|
|
|
ret = copy_from_iova(cp->mdev, idaws, ccw->cda, idaw_len);
|
|
if (ret)
|
|
goto out_free_idaws;
|
|
|
|
ccw->cda = virt_to_phys(idaws);
|
|
|
|
for (i = 0; i < idaw_nr; i++) {
|
|
idaw_iova = *(idaws + i);
|
|
|
|
ret = pfn_array_alloc_pin(pat->pat_pa + i, cp->mdev,
|
|
idaw_iova, 1);
|
|
if (ret < 0)
|
|
goto out_free_idaws;
|
|
}
|
|
|
|
pfn_array_table_idal_create_words(pat, idaws);
|
|
|
|
return 0;
|
|
|
|
out_free_idaws:
|
|
kfree(idaws);
|
|
out_unpin:
|
|
pfn_array_table_unpin_free(pat, cp->mdev);
|
|
out_init:
|
|
ccw->cda = 0;
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Fetch one ccw.
|
|
* To reduce memory copy, we'll pin the cda page in memory,
|
|
* and to get rid of the cda 2G limitiaion of ccw1, we'll translate
|
|
* direct ccws to idal ccws.
|
|
*/
|
|
static int ccwchain_fetch_one(struct ccwchain *chain,
|
|
int idx,
|
|
struct channel_program *cp)
|
|
{
|
|
struct ccw1 *ccw = chain->ch_ccw + idx;
|
|
|
|
if (ccw_is_test(ccw) || ccw_is_noop(ccw))
|
|
return 0;
|
|
|
|
if (ccw_is_tic(ccw))
|
|
return ccwchain_fetch_tic(chain, idx, cp);
|
|
|
|
if (ccw_is_idal(ccw))
|
|
return ccwchain_fetch_idal(chain, idx, cp);
|
|
|
|
return ccwchain_fetch_direct(chain, idx, cp);
|
|
}
|
|
|
|
/**
|
|
* cp_init() - allocate ccwchains for a channel program.
|
|
* @cp: channel_program on which to perform the operation
|
|
* @mdev: the mediated device to perform pin/unpin operations
|
|
* @orb: control block for the channel program from the guest
|
|
*
|
|
* This creates one or more ccwchain(s), and copies the raw data of
|
|
* the target channel program from @orb->cmd.iova to the new ccwchain(s).
|
|
*
|
|
* Limitations:
|
|
* 1. Supports only prefetch enabled mode.
|
|
* 2. Supports idal(c64) ccw chaining.
|
|
* 3. Supports 4k idaw.
|
|
*
|
|
* Returns:
|
|
* %0 on success and a negative error value on failure.
|
|
*/
|
|
int cp_init(struct channel_program *cp, struct device *mdev, union orb *orb)
|
|
{
|
|
u64 iova = orb->cmd.cpa;
|
|
struct ccwchain *chain;
|
|
int len, ret;
|
|
|
|
/*
|
|
* XXX:
|
|
* Only support prefetch enable mode now.
|
|
*/
|
|
if (!orb->cmd.pfch)
|
|
return -EOPNOTSUPP;
|
|
|
|
INIT_LIST_HEAD(&cp->ccwchain_list);
|
|
memcpy(&cp->orb, orb, sizeof(*orb));
|
|
cp->mdev = mdev;
|
|
|
|
/* Get chain length. */
|
|
len = ccwchain_calc_length(iova, cp);
|
|
if (len < 0)
|
|
return len;
|
|
|
|
/* Alloc mem for the head chain. */
|
|
chain = ccwchain_alloc(cp, len);
|
|
if (!chain)
|
|
return -ENOMEM;
|
|
chain->ch_iova = iova;
|
|
|
|
/* Copy the head chain from guest. */
|
|
ret = copy_ccw_from_iova(cp, chain->ch_ccw, iova, len);
|
|
if (ret) {
|
|
ccwchain_free(chain);
|
|
return ret;
|
|
}
|
|
|
|
/* Now loop for its TICs. */
|
|
ret = ccwchain_loop_tic(chain, cp);
|
|
if (ret)
|
|
cp_unpin_free(cp);
|
|
/* It is safe to force: if not set but idals used
|
|
* ccwchain_calc_length returns an error.
|
|
*/
|
|
cp->orb.cmd.c64 = 1;
|
|
|
|
return ret;
|
|
}
|
|
|
|
|
|
/**
|
|
* cp_free() - free resources for channel program.
|
|
* @cp: channel_program on which to perform the operation
|
|
*
|
|
* This unpins the memory pages and frees the memory space occupied by
|
|
* @cp, which must have been returned by a previous call to cp_init().
|
|
* Otherwise, undefined behavior occurs.
|
|
*/
|
|
void cp_free(struct channel_program *cp)
|
|
{
|
|
cp_unpin_free(cp);
|
|
}
|
|
|
|
/**
|
|
* cp_prefetch() - translate a guest physical address channel program to
|
|
* a real-device runnable channel program.
|
|
* @cp: channel_program on which to perform the operation
|
|
*
|
|
* This function translates the guest-physical-address channel program
|
|
* and stores the result to ccwchain list. @cp must have been
|
|
* initialized by a previous call with cp_init(). Otherwise, undefined
|
|
* behavior occurs.
|
|
* For each chain composing the channel program:
|
|
* - On entry ch_len holds the count of CCWs to be translated.
|
|
* - On exit ch_len is adjusted to the count of successfully translated CCWs.
|
|
* This allows cp_free to find in ch_len the count of CCWs to free in a chain.
|
|
*
|
|
* The S/390 CCW Translation APIS (prefixed by 'cp_') are introduced
|
|
* as helpers to do ccw chain translation inside the kernel. Basically
|
|
* they accept a channel program issued by a virtual machine, and
|
|
* translate the channel program to a real-device runnable channel
|
|
* program.
|
|
*
|
|
* These APIs will copy the ccws into kernel-space buffers, and update
|
|
* the guest phsical addresses with their corresponding host physical
|
|
* addresses. Then channel I/O device drivers could issue the
|
|
* translated channel program to real devices to perform an I/O
|
|
* operation.
|
|
*
|
|
* These interfaces are designed to support translation only for
|
|
* channel programs, which are generated and formatted by a
|
|
* guest. Thus this will make it possible for things like VFIO to
|
|
* leverage the interfaces to passthrough a channel I/O mediated
|
|
* device in QEMU.
|
|
*
|
|
* We support direct ccw chaining by translating them to idal ccws.
|
|
*
|
|
* Returns:
|
|
* %0 on success and a negative error value on failure.
|
|
*/
|
|
int cp_prefetch(struct channel_program *cp)
|
|
{
|
|
struct ccwchain *chain;
|
|
int len, idx, ret;
|
|
|
|
list_for_each_entry(chain, &cp->ccwchain_list, next) {
|
|
len = chain->ch_len;
|
|
for (idx = 0; idx < len; idx++) {
|
|
ret = ccwchain_fetch_one(chain, idx, cp);
|
|
if (ret)
|
|
goto out_err;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
out_err:
|
|
/* Only cleanup the chain elements that were actually translated. */
|
|
chain->ch_len = idx;
|
|
list_for_each_entry_continue(chain, &cp->ccwchain_list, next) {
|
|
chain->ch_len = 0;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* cp_get_orb() - get the orb of the channel program
|
|
* @cp: channel_program on which to perform the operation
|
|
* @intparm: new intparm for the returned orb
|
|
* @lpm: candidate value of the logical-path mask for the returned orb
|
|
*
|
|
* This function returns the address of the updated orb of the channel
|
|
* program. Channel I/O device drivers could use this orb to issue a
|
|
* ssch.
|
|
*/
|
|
union orb *cp_get_orb(struct channel_program *cp, u32 intparm, u8 lpm)
|
|
{
|
|
union orb *orb;
|
|
struct ccwchain *chain;
|
|
struct ccw1 *cpa;
|
|
|
|
orb = &cp->orb;
|
|
|
|
orb->cmd.intparm = intparm;
|
|
orb->cmd.fmt = 1;
|
|
orb->cmd.key = PAGE_DEFAULT_KEY >> 4;
|
|
|
|
if (orb->cmd.lpm == 0)
|
|
orb->cmd.lpm = lpm;
|
|
|
|
chain = list_first_entry(&cp->ccwchain_list, struct ccwchain, next);
|
|
cpa = chain->ch_ccw;
|
|
orb->cmd.cpa = (__u32) __pa(cpa);
|
|
|
|
return orb;
|
|
}
|
|
|
|
/**
|
|
* cp_update_scsw() - update scsw for a channel program.
|
|
* @cp: channel_program on which to perform the operation
|
|
* @scsw: I/O results of the channel program and also the target to be
|
|
* updated
|
|
*
|
|
* @scsw contains the I/O results of the channel program that pointed
|
|
* to by @cp. However what @scsw->cpa stores is a host physical
|
|
* address, which is meaningless for the guest, which is waiting for
|
|
* the I/O results.
|
|
*
|
|
* This function updates @scsw->cpa to its coressponding guest physical
|
|
* address.
|
|
*/
|
|
void cp_update_scsw(struct channel_program *cp, union scsw *scsw)
|
|
{
|
|
struct ccwchain *chain;
|
|
u32 cpa = scsw->cmd.cpa;
|
|
u32 ccw_head, ccw_tail;
|
|
|
|
/*
|
|
* LATER:
|
|
* For now, only update the cmd.cpa part. We may need to deal with
|
|
* other portions of the schib as well, even if we don't return them
|
|
* in the ioctl directly. Path status changes etc.
|
|
*/
|
|
list_for_each_entry(chain, &cp->ccwchain_list, next) {
|
|
ccw_head = (u32)(u64)chain->ch_ccw;
|
|
ccw_tail = (u32)(u64)(chain->ch_ccw + chain->ch_len - 1);
|
|
|
|
if ((ccw_head <= cpa) && (cpa <= ccw_tail)) {
|
|
/*
|
|
* (cpa - ccw_head) is the offset value of the host
|
|
* physical ccw to its chain head.
|
|
* Adding this value to the guest physical ccw chain
|
|
* head gets us the guest cpa.
|
|
*/
|
|
cpa = chain->ch_iova + (cpa - ccw_head);
|
|
break;
|
|
}
|
|
}
|
|
|
|
scsw->cmd.cpa = cpa;
|
|
}
|
|
|
|
/**
|
|
* cp_iova_pinned() - check if an iova is pinned for a ccw chain.
|
|
* @cp: channel_program on which to perform the operation
|
|
* @iova: the iova to check
|
|
*
|
|
* If the @iova is currently pinned for the ccw chain, return true;
|
|
* else return false.
|
|
*/
|
|
bool cp_iova_pinned(struct channel_program *cp, u64 iova)
|
|
{
|
|
struct ccwchain *chain;
|
|
int i;
|
|
|
|
list_for_each_entry(chain, &cp->ccwchain_list, next) {
|
|
for (i = 0; i < chain->ch_len; i++)
|
|
if (pfn_array_table_iova_pinned(chain->ch_pat + i,
|
|
iova))
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|