linux_dsm_epyc7002/drivers/gpu/drm/msm/msm_iommu.c
Stephane Viau 87e956e9be drm/msm: fix IOMMU cleanup for -EPROBE_DEFER
If probe fails after IOMMU is attached, we need to detach in order to
clean up properly.  Before this change, IOMMU faults would occur if the
probe failed (-EPROBE_DEFER).

Signed-off-by: Stephane Viau <sviau@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>
2014-06-22 08:32:10 -04:00

166 lines
3.9 KiB
C

/*
* Copyright (C) 2013 Red Hat
* Author: Rob Clark <robdclark@gmail.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "msm_drv.h"
#include "msm_mmu.h"
struct msm_iommu {
struct msm_mmu base;
struct iommu_domain *domain;
};
#define to_msm_iommu(x) container_of(x, struct msm_iommu, base)
static int msm_fault_handler(struct iommu_domain *iommu, struct device *dev,
unsigned long iova, int flags, void *arg)
{
DBG("*** fault: iova=%08lx, flags=%d", iova, flags);
return -ENOSYS;
}
static int msm_iommu_attach(struct msm_mmu *mmu, const char **names, int cnt)
{
struct drm_device *dev = mmu->dev;
struct msm_iommu *iommu = to_msm_iommu(mmu);
int i, ret;
for (i = 0; i < cnt; i++) {
struct device *msm_iommu_get_ctx(const char *ctx_name);
struct device *ctx = msm_iommu_get_ctx(names[i]);
if (IS_ERR_OR_NULL(ctx)) {
dev_warn(dev->dev, "couldn't get %s context", names[i]);
continue;
}
ret = iommu_attach_device(iommu->domain, ctx);
if (ret) {
dev_warn(dev->dev, "could not attach iommu to %s", names[i]);
return ret;
}
}
return 0;
}
static void msm_iommu_detach(struct msm_mmu *mmu, const char **names, int cnt)
{
struct msm_iommu *iommu = to_msm_iommu(mmu);
int i;
for (i = 0; i < cnt; i++) {
struct device *msm_iommu_get_ctx(const char *ctx_name);
struct device *ctx = msm_iommu_get_ctx(names[i]);
if (IS_ERR_OR_NULL(ctx))
continue;
iommu_detach_device(iommu->domain, ctx);
}
}
static int msm_iommu_map(struct msm_mmu *mmu, uint32_t iova,
struct sg_table *sgt, unsigned len, int prot)
{
struct msm_iommu *iommu = to_msm_iommu(mmu);
struct iommu_domain *domain = iommu->domain;
struct scatterlist *sg;
unsigned int da = iova;
unsigned int i, j;
int ret;
if (!domain || !sgt)
return -EINVAL;
for_each_sg(sgt->sgl, sg, sgt->nents, i) {
u32 pa = sg_phys(sg) - sg->offset;
size_t bytes = sg->length + sg->offset;
VERB("map[%d]: %08x %08x(%x)", i, iova, pa, bytes);
ret = iommu_map(domain, da, pa, bytes, prot);
if (ret)
goto fail;
da += bytes;
}
return 0;
fail:
da = iova;
for_each_sg(sgt->sgl, sg, i, j) {
size_t bytes = sg->length + sg->offset;
iommu_unmap(domain, da, bytes);
da += bytes;
}
return ret;
}
static int msm_iommu_unmap(struct msm_mmu *mmu, uint32_t iova,
struct sg_table *sgt, unsigned len)
{
struct msm_iommu *iommu = to_msm_iommu(mmu);
struct iommu_domain *domain = iommu->domain;
struct scatterlist *sg;
unsigned int da = iova;
int i;
for_each_sg(sgt->sgl, sg, sgt->nents, i) {
size_t bytes = sg->length + sg->offset;
size_t unmapped;
unmapped = iommu_unmap(domain, da, bytes);
if (unmapped < bytes)
return unmapped;
VERB("unmap[%d]: %08x(%x)", i, iova, bytes);
BUG_ON(!PAGE_ALIGNED(bytes));
da += bytes;
}
return 0;
}
static void msm_iommu_destroy(struct msm_mmu *mmu)
{
struct msm_iommu *iommu = to_msm_iommu(mmu);
iommu_domain_free(iommu->domain);
kfree(iommu);
}
static const struct msm_mmu_funcs funcs = {
.attach = msm_iommu_attach,
.detach = msm_iommu_detach,
.map = msm_iommu_map,
.unmap = msm_iommu_unmap,
.destroy = msm_iommu_destroy,
};
struct msm_mmu *msm_iommu_new(struct drm_device *dev, struct iommu_domain *domain)
{
struct msm_iommu *iommu;
iommu = kzalloc(sizeof(*iommu), GFP_KERNEL);
if (!iommu)
return ERR_PTR(-ENOMEM);
iommu->domain = domain;
msm_mmu_init(&iommu->base, dev, &funcs);
iommu_set_fault_handler(domain, msm_fault_handler, dev);
return &iommu->base;
}