Patchwork [v5] Align PCI capabilities in pci_find_space

login
register
mail settings
Submitter mjr@cs.wisc.edu
Date Sept. 29, 2012, 2:51 p.m.
Message ID <1348930263-2915-1-git-send-email-mjr@cs.wisc.edu>
Download mbox | patch
Permalink /patch/188032/
State New
Headers show

Comments

mjr@cs.wisc.edu - Sept. 29, 2012, 2:51 p.m.
The current implementation of pci_find_space does not correctly align
PCI capabilities in the PCI configuration space.  It also does not
support PCI-Express devices.  This patch fixes these issues.

Thanks to Alex Williamson for feedback.

Signed-off-by: Matt Renzelmann <mjr@cs.wisc.edu>
---

Braces added.

 hw/pci.c |   36 ++++++++++++++++++++++++++++--------
 1 files changed, 28 insertions(+), 8 deletions(-)
mjr@cs.wisc.edu - Oct. 11, 2012, 7:50 p.m.
Hi,

I just wanted to ping the status of this patch:
http://patchwork.ozlabs.org/patch/188032/

This version is different from v4 only in that it adds braces as recommended by
Blue Swirl.

Thanks and regards,
Matt


> -----Original Message-----
> From: qemu-devel-bounces+mjr=cs.wisc.edu@nongnu.org [mailto:qemu-devel-
> bounces+mjr=cs.wisc.edu@nongnu.org] On Behalf Of Matt Renzelmann
> Sent: Saturday, September 29, 2012 9:51 AM
> To: qemu-devel@nongnu.org
> Cc: blauwirbel@gmail.com; alex.williamson@redhat.com
> Subject: [Qemu-devel] [PATCH v5] Align PCI capabilities in pci_find_space
> 
> The current implementation of pci_find_space does not correctly align
> PCI capabilities in the PCI configuration space.  It also does not
> support PCI-Express devices.  This patch fixes these issues.
> 
> Thanks to Alex Williamson for feedback.
> 
> Signed-off-by: Matt Renzelmann <mjr@cs.wisc.edu>
> ---
> 
> Braces added.
> 
>  hw/pci.c |   36 ++++++++++++++++++++++++++++--------
>  1 files changed, 28 insertions(+), 8 deletions(-)
> 
> diff --git a/hw/pci.c b/hw/pci.c
> index f855cf3..0f24225 100644
> --- a/hw/pci.c
> +++ b/hw/pci.c
> @@ -1626,19 +1626,39 @@ PCIDevice *pci_create_simple(PCIBus *bus, int devfn,
> const char *name)
>      return pci_create_simple_multifunction(bus, devfn, false, name);
>  }
> 
> -static int pci_find_space(PCIDevice *pdev, uint8_t size)
> +static int pci_find_space(PCIDevice *pdev, uint32_t start,
> +                          uint32_t end, uint32_t size)
>  {
> -    int config_size = pci_config_size(pdev);
> -    int offset = PCI_CONFIG_HEADER_SIZE;
> +    int offset = start;
>      int i;
> -    for (i = PCI_CONFIG_HEADER_SIZE; i < config_size; ++i)
> -        if (pdev->used[i])
> -            offset = i + 1;
> -        else if (i - offset + 1 == size)
> +    uint32_t *dword_used = &pdev->used[start];
> +
> +    assert(pci_config_size(pdev) >= end);
> +    assert(!(start & 0x3));
> +
> +    /* This approach ensures the capability is dword-aligned, as
> +       required by the PCI and PCI-E specifications */
> +    for (i = start; i < end; i += 4, dword_used++) {
> +        if (*dword_used) {
> +            offset = i + 4;
> +        } else if (i - offset + 4 >= size) {
>              return offset;
> +        }
> +    }
> +
>      return 0;
>  }
> 
> +static int pci_find_legacy_space(PCIDevice *pdev, uint8_t size) {
> +    return pci_find_space(pdev, PCI_CONFIG_HEADER_SIZE,
> +                          PCI_CONFIG_SPACE_SIZE, size);
> +}
> +
> +static int pci_find_express_space(PCIDevice *pdev, uint16_t size) {
> +    return pci_find_space(pdev, PCI_CONFIG_SPACE_SIZE,
> +                          PCIE_CONFIG_SPACE_SIZE, size);
> +}
> +
>  static uint8_t pci_find_capability_list(PCIDevice *pdev, uint8_t cap_id,
>                                          uint8_t *prev_p)
>  {
> @@ -1826,7 +1846,7 @@ int pci_add_capability(PCIDevice *pdev, uint8_t cap_id,
>      int i, overlapping_cap;
> 
>      if (!offset) {
> -        offset = pci_find_space(pdev, size);
> +        offset = pci_find_legacy_space(pdev, size);
>          if (!offset) {
>              return -ENOSPC;
>          }
> --
> 1.7.5.4
>
Andreas Färber - Oct. 11, 2012, 8:04 p.m.
Am 11.10.2012 21:50, schrieb Matt Renzelmann:
> Hi,
> 
> I just wanted to ping the status of this patch:
> http://patchwork.ozlabs.org/patch/188032/
> 
> This version is different from v4 only in that it adds braces as recommended by
> Blue Swirl.

PCI patches should cc the PCI maintainer, cf. MAINTAINERS.

Andreas

> 
> Thanks and regards,
> Matt
> 
> 
>> -----Original Message-----
>> From: qemu-devel-bounces+mjr=cs.wisc.edu@nongnu.org [mailto:qemu-devel-
>> bounces+mjr=cs.wisc.edu@nongnu.org] On Behalf Of Matt Renzelmann
>> Sent: Saturday, September 29, 2012 9:51 AM
>> To: qemu-devel@nongnu.org
>> Cc: blauwirbel@gmail.com; alex.williamson@redhat.com
>> Subject: [Qemu-devel] [PATCH v5] Align PCI capabilities in pci_find_space
>>
>> The current implementation of pci_find_space does not correctly align
>> PCI capabilities in the PCI configuration space.  It also does not
>> support PCI-Express devices.  This patch fixes these issues.
>>
>> Thanks to Alex Williamson for feedback.
>>
>> Signed-off-by: Matt Renzelmann <mjr@cs.wisc.edu>
>> ---
>>
>> Braces added.
>>
>>  hw/pci.c |   36 ++++++++++++++++++++++++++++--------
>>  1 files changed, 28 insertions(+), 8 deletions(-)
>>
>> diff --git a/hw/pci.c b/hw/pci.c
>> index f855cf3..0f24225 100644
>> --- a/hw/pci.c
>> +++ b/hw/pci.c
>> @@ -1626,19 +1626,39 @@ PCIDevice *pci_create_simple(PCIBus *bus, int devfn,
>> const char *name)
>>      return pci_create_simple_multifunction(bus, devfn, false, name);
>>  }
>>
>> -static int pci_find_space(PCIDevice *pdev, uint8_t size)
>> +static int pci_find_space(PCIDevice *pdev, uint32_t start,
>> +                          uint32_t end, uint32_t size)
>>  {
>> -    int config_size = pci_config_size(pdev);
>> -    int offset = PCI_CONFIG_HEADER_SIZE;
>> +    int offset = start;
>>      int i;
>> -    for (i = PCI_CONFIG_HEADER_SIZE; i < config_size; ++i)
>> -        if (pdev->used[i])
>> -            offset = i + 1;
>> -        else if (i - offset + 1 == size)
>> +    uint32_t *dword_used = &pdev->used[start];
>> +
>> +    assert(pci_config_size(pdev) >= end);
>> +    assert(!(start & 0x3));
>> +
>> +    /* This approach ensures the capability is dword-aligned, as
>> +       required by the PCI and PCI-E specifications */
>> +    for (i = start; i < end; i += 4, dword_used++) {
>> +        if (*dword_used) {
>> +            offset = i + 4;
>> +        } else if (i - offset + 4 >= size) {
>>              return offset;
>> +        }
>> +    }
>> +
>>      return 0;
>>  }
>>
>> +static int pci_find_legacy_space(PCIDevice *pdev, uint8_t size) {
>> +    return pci_find_space(pdev, PCI_CONFIG_HEADER_SIZE,
>> +                          PCI_CONFIG_SPACE_SIZE, size);
>> +}
>> +
>> +static int pci_find_express_space(PCIDevice *pdev, uint16_t size) {
>> +    return pci_find_space(pdev, PCI_CONFIG_SPACE_SIZE,
>> +                          PCIE_CONFIG_SPACE_SIZE, size);
>> +}
>> +
>>  static uint8_t pci_find_capability_list(PCIDevice *pdev, uint8_t cap_id,
>>                                          uint8_t *prev_p)
>>  {
>> @@ -1826,7 +1846,7 @@ int pci_add_capability(PCIDevice *pdev, uint8_t cap_id,
>>      int i, overlapping_cap;
>>
>>      if (!offset) {
>> -        offset = pci_find_space(pdev, size);
>> +        offset = pci_find_legacy_space(pdev, size);
>>          if (!offset) {
>>              return -ENOSPC;
>>          }
>> --
>> 1.7.5.4
>>
> 
> 
>

Patch

diff --git a/hw/pci.c b/hw/pci.c
index f855cf3..0f24225 100644
--- a/hw/pci.c
+++ b/hw/pci.c
@@ -1626,19 +1626,39 @@  PCIDevice *pci_create_simple(PCIBus *bus, int devfn, const char *name)
     return pci_create_simple_multifunction(bus, devfn, false, name);
 }
 
-static int pci_find_space(PCIDevice *pdev, uint8_t size)
+static int pci_find_space(PCIDevice *pdev, uint32_t start,
+                          uint32_t end, uint32_t size)
 {
-    int config_size = pci_config_size(pdev);
-    int offset = PCI_CONFIG_HEADER_SIZE;
+    int offset = start;
     int i;
-    for (i = PCI_CONFIG_HEADER_SIZE; i < config_size; ++i)
-        if (pdev->used[i])
-            offset = i + 1;
-        else if (i - offset + 1 == size)
+    uint32_t *dword_used = &pdev->used[start];
+
+    assert(pci_config_size(pdev) >= end);
+    assert(!(start & 0x3));
+
+    /* This approach ensures the capability is dword-aligned, as
+       required by the PCI and PCI-E specifications */
+    for (i = start; i < end; i += 4, dword_used++) {
+        if (*dword_used) {
+            offset = i + 4;
+        } else if (i - offset + 4 >= size) {
             return offset;
+        }
+    }
+
     return 0;
 }
 
+static int pci_find_legacy_space(PCIDevice *pdev, uint8_t size) {
+    return pci_find_space(pdev, PCI_CONFIG_HEADER_SIZE,
+                          PCI_CONFIG_SPACE_SIZE, size);
+}
+
+static int pci_find_express_space(PCIDevice *pdev, uint16_t size) {
+    return pci_find_space(pdev, PCI_CONFIG_SPACE_SIZE,
+                          PCIE_CONFIG_SPACE_SIZE, size);
+}
+
 static uint8_t pci_find_capability_list(PCIDevice *pdev, uint8_t cap_id,
                                         uint8_t *prev_p)
 {
@@ -1826,7 +1846,7 @@  int pci_add_capability(PCIDevice *pdev, uint8_t cap_id,
     int i, overlapping_cap;
 
     if (!offset) {
-        offset = pci_find_space(pdev, size);
+        offset = pci_find_legacy_space(pdev, size);
         if (!offset) {
             return -ENOSPC;
         }