[PATCH v13 01/16] PCI: Let pci_mmap_page_range() take resource address
From: Yinghai Lu
Date: Fri Jun 17 2016 - 22:28:25 EST
In 8c05cd08a7 ("PCI: fix offset check for sysfs mmapped files"), try
to check exposed value with resource start/end in proc mmap path.
| start = vma->vm_pgoff;
| size = ((pci_resource_len(pdev, resno) - 1) >> PAGE_SHIFT) + 1;
| pci_start = (mmap_api == PCI_MMAP_PROCFS) ?
| pci_resource_start(pdev, resno) >> PAGE_SHIFT : 0;
| if (start >= pci_start && start < pci_start + size &&
| start + nr <= pci_start + size)
That breaks sparc that exposed value is BAR value, and need to be offseted
to resource address.
Original pci_mmap_page_range() is taking PCI BAR value aka usr_address.
Bjorn found out that it would be much simple to pass resource address
directly and avoid extra those __pci_mmap_make_offset.
In this patch:
1. in proc path: proc_bus_pci_mmap, try convert back to resource
before calling pci_mmap_page_range
2. in sysfs path: pci_mmap_resource will just offset with resource start.
3. all pci_mmap_page_range will have vma->vm_pgoff with in resource
range instead of BAR value.
4. skip calling __pci_mmap_make_offset, as the checking is done
in pci_mmap_fits().
-v2: add pci_user_to_resource and remove __pci_mmap_make_offset
-v3: pass resource pointer with pci_mmap_page_range()
-v4: put __pci_mmap_make_offset() removing to following patch
seperate /sys io access alignment checking to another patch
updated after Bjorn's pci_resource_to_user() changes.
Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx>
Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
Cc: sparclinux@xxxxxxxxxxxxxxx
Cc: linux-xtensa@xxxxxxxxxxxxxxxx
---
arch/microblaze/pci/pci-common.c | 11 +++++---
arch/powerpc/kernel/pci-common.c | 11 +++++---
arch/sparc/kernel/pci.c | 4 ---
arch/xtensa/kernel/pci.c | 13 +++++++--
drivers/pci/pci-sysfs.c | 23 +++++++++------
drivers/pci/pci.h | 2 +-
drivers/pci/proc.c | 60 ++++++++++++++++++++++++++++++++++------
7 files changed, 91 insertions(+), 33 deletions(-)
diff --git a/arch/microblaze/pci/pci-common.c b/arch/microblaze/pci/pci-common.c
index 81556b8..9e3bc05 100644
--- a/arch/microblaze/pci/pci-common.c
+++ b/arch/microblaze/pci/pci-common.c
@@ -282,12 +282,15 @@ int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
{
resource_size_t offset =
((resource_size_t)vma->vm_pgoff) << PAGE_SHIFT;
- struct resource *rp;
int ret;
- rp = __pci_mmap_make_offset(dev, &offset, mmap_state);
- if (rp == NULL)
- return -EINVAL;
+ if (mmap_state == pci_mmap_io) {
+ struct pci_controller *hose = pci_bus_to_host(dev->bus);
+
+ /* hose should never be NULL */
+ offset += hose->io_base_phys -
+ ((unsigned long)hose->io_base_virt - _IO_BASE);
+ }
vma->vm_pgoff = offset >> PAGE_SHIFT;
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c
index 6de6e0e..53ba098 100644
--- a/arch/powerpc/kernel/pci-common.c
+++ b/arch/powerpc/kernel/pci-common.c
@@ -420,12 +420,15 @@ int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
{
resource_size_t offset =
((resource_size_t)vma->vm_pgoff) << PAGE_SHIFT;
- struct resource *rp;
int ret;
- rp = __pci_mmap_make_offset(dev, &offset, mmap_state);
- if (rp == NULL)
- return -EINVAL;
+ if (mmap_state == pci_mmap_io) {
+ struct pci_controller *hose = pci_bus_to_host(dev->bus);
+
+ /* hose should never be NULL */
+ offset += hose->io_base_phys -
+ ((unsigned long)hose->io_base_virt - _IO_BASE);
+ }
vma->vm_pgoff = offset >> PAGE_SHIFT;
if (write_combine)
diff --git a/arch/sparc/kernel/pci.c b/arch/sparc/kernel/pci.c
index 9c1878f..5f2d78e 100644
--- a/arch/sparc/kernel/pci.c
+++ b/arch/sparc/kernel/pci.c
@@ -868,10 +868,6 @@ int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
{
int ret;
- ret = __pci_mmap_make_offset(dev, vma, mmap_state);
- if (ret < 0)
- return ret;
-
__pci_mmap_set_pgprot(dev, vma, mmap_state);
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
diff --git a/arch/xtensa/kernel/pci.c b/arch/xtensa/kernel/pci.c
index b848cc3..4c5f1fa 100644
--- a/arch/xtensa/kernel/pci.c
+++ b/arch/xtensa/kernel/pci.c
@@ -366,11 +366,18 @@ int pci_mmap_page_range(struct pci_dev *dev, struct vm_area_struct *vma,
enum pci_mmap_state mmap_state,
int write_combine)
{
+ unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
int ret;
- ret = __pci_mmap_make_offset(dev, vma, mmap_state);
- if (ret < 0)
- return ret;
+ if (mmap_state == pci_mmap_io) {
+ struct pci_controller *pci_ctrl =
+ (struct pci_controller *)dev->sysdata;
+
+ /* pci_ctrl should never be NULL */
+ offset += pci_ctrl->io_space.start - pci_ctrl->io_space.base;
+ }
+
+ vma->vm_pgoff = offset >> PAGE_SHIFT;
__pci_mmap_set_pgprot(dev, vma, mmap_state, write_combine);
diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index d319a9c..82b98dd 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -967,12 +967,23 @@ void pci_remove_legacy_files(struct pci_bus *b)
#ifdef HAVE_PCI_MMAP
int pci_mmap_fits(struct pci_dev *pdev, int resno, struct vm_area_struct *vma,
+ enum pci_mmap_state mmap_type,
enum pci_mmap_api mmap_api)
{
unsigned long nr, start, size, pci_start;
+ int flags;
if (pci_resource_len(pdev, resno) == 0)
return 0;
+
+ if (mmap_type == pci_mmap_mem)
+ flags = IORESOURCE_MEM;
+ else
+ flags = IORESOURCE_IO;
+
+ if (!(pci_resource_flags(pdev, resno) & flags))
+ return 0;
+
nr = vma_pages(vma);
start = vma->vm_pgoff;
size = ((pci_resource_len(pdev, resno) - 1) >> PAGE_SHIFT) + 1;
@@ -999,7 +1010,6 @@ static int pci_mmap_resource(struct kobject *kobj, struct bin_attribute *attr,
struct pci_dev *pdev = to_pci_dev(kobj_to_dev(kobj));
struct resource *res = attr->private;
enum pci_mmap_state mmap_type;
- resource_size_t start, end;
int i;
for (i = 0; i < PCI_ROM_RESOURCE; i++)
@@ -1011,7 +1021,8 @@ static int pci_mmap_resource(struct kobject *kobj, struct bin_attribute *attr,
if (res->flags & IORESOURCE_MEM && iomem_is_exclusive(res->start))
return -EINVAL;
- if (!pci_mmap_fits(pdev, i, vma, PCI_MMAP_SYSFS)) {
+ mmap_type = res->flags & IORESOURCE_MEM ? pci_mmap_mem : pci_mmap_io;
+ if (!pci_mmap_fits(pdev, i, vma, mmap_type, PCI_MMAP_SYSFS)) {
WARN(1, "process \"%s\" tried to map 0x%08lx bytes at page 0x%08lx on %s BAR %d (start 0x%16Lx, size 0x%16Lx)\n",
current->comm, vma->vm_end-vma->vm_start, vma->vm_pgoff,
pci_name(pdev), i,
@@ -1020,13 +1031,7 @@ static int pci_mmap_resource(struct kobject *kobj, struct bin_attribute *attr,
return -EINVAL;
}
- /* pci_mmap_page_range() expects the same kind of entry as coming
- * from /proc/bus/pci/ which is a "user visible" value. If this is
- * different from the resource itself, arch will do necessary fixup.
- */
- pci_resource_to_user(pdev, i, res, &start, &end);
- vma->vm_pgoff += start >> PAGE_SHIFT;
- mmap_type = res->flags & IORESOURCE_MEM ? pci_mmap_mem : pci_mmap_io;
+ vma->vm_pgoff += res->start >> PAGE_SHIFT;
return pci_mmap_page_range(pdev, vma, mmap_type, write_combine);
}
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index a814bbb..7d339c3 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -30,7 +30,7 @@ enum pci_mmap_api {
PCI_MMAP_PROCFS /* mmap on /proc/bus/pci/<BDF> */
};
int pci_mmap_fits(struct pci_dev *pdev, int resno, struct vm_area_struct *vmai,
- enum pci_mmap_api mmap_api);
+ enum pci_mmap_state mmap_type, enum pci_mmap_api mmap_api);
#endif
int pci_probe_reset_function(struct pci_dev *dev);
diff --git a/drivers/pci/proc.c b/drivers/pci/proc.c
index 2408abe..fadab8a 100644
--- a/drivers/pci/proc.c
+++ b/drivers/pci/proc.c
@@ -227,24 +227,68 @@ static long proc_bus_pci_ioctl(struct file *file, unsigned int cmd,
}
#ifdef HAVE_PCI_MMAP
+
+static int pci_user_to_resource(struct pci_dev *dev, resource_size_t *offset,
+ int flags)
+{
+ int i;
+
+ for (i = 0; i < PCI_ROM_RESOURCE; i++) {
+ resource_size_t start, end;
+ struct resource *res = &dev->resource[i];
+
+ if (!(res->flags & flags))
+ continue;
+
+ if (pci_resource_len(dev, i) == 0)
+ continue;
+
+ /*
+ * here *offset is PAGE_SIZE aligned from caller.
+ * need align start/end for io port resource that is
+ * usually not PAGE_SIZE aligned.
+ * that means we let it go if they falls in same page.
+ */
+ pci_resource_to_user(dev, i, res, &start, &end);
+ if ((start & PAGE_MASK) <= *offset &&
+ *offset <= (end & PAGE_MASK)) {
+ *offset = res->start + (*offset - start);
+ return i;
+ }
+ }
+
+ return -ENODEV;
+}
+
static int proc_bus_pci_mmap(struct file *file, struct vm_area_struct *vma)
{
struct pci_dev *dev = PDE_DATA(file_inode(file));
struct pci_filp_private *fpriv = file->private_data;
- int i, ret, write_combine;
+ resource_size_t offset;
+ int i, ret, flags, write_combine;
if (!capable(CAP_SYS_RAWIO))
return -EPERM;
- /* Make sure the caller is mapping a real resource for this device */
- for (i = 0; i < PCI_ROM_RESOURCE; i++) {
- if (pci_mmap_fits(dev, i, vma, PCI_MMAP_PROCFS))
- break;
- }
-
- if (i >= PCI_ROM_RESOURCE)
+ offset = vma->vm_pgoff << PAGE_SHIFT;
+ if (fpriv->mmap_state == pci_mmap_mem)
+ flags = IORESOURCE_MEM;
+ else
+ flags = IORESOURCE_IO;
+ i = pci_user_to_resource(dev, &offset, flags);
+ if (i < 0)
return -ENODEV;
+ vma->vm_pgoff = offset >> PAGE_SHIFT;
+ if (!pci_mmap_fits(dev, i, vma, fpriv->mmap_state, PCI_MMAP_PROCFS)) {
+ WARN(1, "process \"%s\" tried to map 0x%08lx bytes at page 0x%08lx on %s BAR %d (start 0x%16Lx, size 0x%16Lx)\n",
+ current->comm, vma->vm_end-vma->vm_start, vma->vm_pgoff,
+ pci_name(dev), i,
+ (u64)pci_resource_start(dev, i),
+ (u64)pci_resource_len(dev, i));
+ return -EINVAL;
+ }
+
if (fpriv->mmap_state == pci_mmap_mem)
write_combine = fpriv->write_combine;
else
--
2.8.3