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Revert "remoteproc: qcom_q6v5_mss: map/unmap metadata region before/after use"

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This reverts commit fc156629b2.

This commit manages to do three API violations at once:

 - dereference the return value of dma_alloc_attrs with the
   DMA_ATTR_NO_KERNEL_MAPPING mapping, which is clearly forbidden and
   will do the wrong thing on various dma mapping implementations.  The
   fact that dma-direct uses a struct page as a cookie is an undocumented
   implementation detail
 - include dma-map-ops.h and use pgprot_dmacoherent despite a clear
   comment documenting that this is not acceptable
 - use of the VM_DMA_COHERENT for something that is not the dma-mapping
   code
 - use of VM_FLUSH_RESET_PERMS for vmap, while it is only supported for
   vmalloc

Acked-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sibi Sankar <quic_sibis@quicinc.com>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230117085840.32356-6-quic_sibis@quicinc.com
This commit is contained in:
Christoph Hellwig 2023-01-17 14:28:34 +05:30 committed by Bjorn Andersson
parent eb48137d78
commit a899d542b6
1 changed files with 6 additions and 32 deletions
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38
drivers/remoteproc/qcom_q6v5_mss.c
View File

@ -10,7 +10,6 @@
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/devcoredump.h>
#include <linux/dma-map-ops.h>
#include <linux/dma-mapping.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
@ -961,52 +960,27 @@ static void q6v5proc_halt_axi_port(struct q6v5 *qproc,
static int q6v5_mpss_init_image(struct q6v5 *qproc, const struct firmware *fw,
const char *fw_name)
{
unsigned long dma_attrs = DMA_ATTR_FORCE_CONTIGUOUS | DMA_ATTR_NO_KERNEL_MAPPING;
unsigned long flags = VM_DMA_COHERENT | VM_FLUSH_RESET_PERMS;
struct page **pages;
struct page *page;
unsigned long dma_attrs = DMA_ATTR_FORCE_CONTIGUOUS;
dma_addr_t phys;
void *metadata;
int mdata_perm;
int xferop_ret;
size_t size;
void *vaddr;
int count;
void *ptr;
int ret;
int i;
metadata = qcom_mdt_read_metadata(fw, &size, fw_name, qproc->dev);
if (IS_ERR(metadata))
return PTR_ERR(metadata);
page = dma_alloc_attrs(qproc->dev, size, &phys, GFP_KERNEL, dma_attrs);
if (!page) {
ptr = dma_alloc_attrs(qproc->dev, size, &phys, GFP_KERNEL, dma_attrs);
if (!ptr) {
kfree(metadata);
dev_err(qproc->dev, "failed to allocate mdt buffer\n");
return -ENOMEM;
}
count = PAGE_ALIGN(size) >> PAGE_SHIFT;
pages = kmalloc_array(count, sizeof(struct page *), GFP_KERNEL);
if (!pages) {
ret = -ENOMEM;
goto free_dma_attrs;
}
for (i = 0; i < count; i++)
pages[i] = nth_page(page, i);
vaddr = vmap(pages, count, flags, pgprot_dmacoherent(PAGE_KERNEL));
kfree(pages);
if (!vaddr) {
dev_err(qproc->dev, "unable to map memory region: %pa+%zx\n", &phys, size);
ret = -EBUSY;
goto free_dma_attrs;
}
memcpy(vaddr, metadata, size);
vunmap(vaddr);
memcpy(ptr, metadata, size);
/* Hypervisor mapping to access metadata by modem */
mdata_perm = BIT(QCOM_SCM_VMID_HLOS);
@ -1036,7 +1010,7 @@ static int q6v5_mpss_init_image(struct q6v5 *qproc, const struct firmware *fw,
"mdt buffer not reclaimed system may become unstable\n");
free_dma_attrs:
dma_free_attrs(qproc->dev, size, page, phys, dma_attrs);
dma_free_attrs(qproc->dev, size, ptr, phys, dma_attrs);
kfree(metadata);
return ret < 0 ? ret : 0;