[for-5.0,v11,12/20] qapi: Introduce DEFINE_PROP_INTERVAL
diff mbox series

Message ID 20191122182943.4656-13-eric.auger@redhat.com
State New
Headers show
Series
  • VIRTIO-IOMMU device
Related show

Commit Message

Auger Eric Nov. 22, 2019, 6:29 p.m. UTC
Introduce a new property defining a labelled interval:
<low address>,<high address>,label.

This will be used to encode reserved IOVA regions. The label
is left undefined to ease reuse accross use cases.

For instance, in virtio-iommu use case, reserved IOVA regions
will be passed by the machine code to the virtio-iommu-pci
device (an array of those). The label will match the
virtio_iommu_probe_resv_mem subtype value:
- VIRTIO_IOMMU_RESV_MEM_T_RESERVED (0)
- VIRTIO_IOMMU_RESV_MEM_T_MSI (1)

This is used to inform the virtio-iommu-pci device it should
bypass the MSI region: 0xfee00000, 0xfeefffff, 1.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
---
 hw/core/qdev-properties.c    | 90 ++++++++++++++++++++++++++++++++++++
 include/exec/memory.h        |  6 +++
 include/hw/qdev-properties.h |  3 ++
 include/qemu/typedefs.h      |  1 +
 4 files changed, 100 insertions(+)

Comments

Dr. David Alan Gilbert Nov. 22, 2019, 7:03 p.m. UTC | #1
* Eric Auger (eric.auger@redhat.com) wrote:
> Introduce a new property defining a labelled interval:
> <low address>,<high address>,label.
> 
> This will be used to encode reserved IOVA regions. The label
> is left undefined to ease reuse accross use cases.
> 
> For instance, in virtio-iommu use case, reserved IOVA regions
> will be passed by the machine code to the virtio-iommu-pci
> device (an array of those). The label will match the
> virtio_iommu_probe_resv_mem subtype value:
> - VIRTIO_IOMMU_RESV_MEM_T_RESERVED (0)
> - VIRTIO_IOMMU_RESV_MEM_T_MSI (1)
> 
> This is used to inform the virtio-iommu-pci device it should
> bypass the MSI region: 0xfee00000, 0xfeefffff, 1.
> 
> Signed-off-by: Eric Auger <eric.auger@redhat.com>
> ---
>  hw/core/qdev-properties.c    | 90 ++++++++++++++++++++++++++++++++++++
>  include/exec/memory.h        |  6 +++
>  include/hw/qdev-properties.h |  3 ++
>  include/qemu/typedefs.h      |  1 +
>  4 files changed, 100 insertions(+)
> 
> diff --git a/hw/core/qdev-properties.c b/hw/core/qdev-properties.c
> index ac28890e5a..8d70f34e37 100644
> --- a/hw/core/qdev-properties.c
> +++ b/hw/core/qdev-properties.c
> @@ -13,6 +13,7 @@
>  #include "qapi/visitor.h"
>  #include "chardev/char.h"
>  #include "qemu/uuid.h"
> +#include "qemu/cutils.h"
>  
>  void qdev_prop_set_after_realize(DeviceState *dev, const char *name,
>                                    Error **errp)
> @@ -585,6 +586,95 @@ const PropertyInfo qdev_prop_macaddr = {
>      .set   = set_mac,
>  };
>  
> +/* --- Labelled Interval --- */
> +
> +/*
> + * accepted syntax versions:
> + *   <low address>,<high address>,<type>
> + *   where low/high addresses are uint64_t in hexa (feat. 0x prefix)
> + *   and type is an unsigned integer
> + */
> +static void get_interval(Object *obj, Visitor *v, const char *name,
> +                         void *opaque, Error **errp)
> +{
> +    DeviceState *dev = DEVICE(obj);
> +    Property *prop = opaque;
> +    Interval *interval = qdev_get_prop_ptr(dev, prop);
> +    char buffer[64];
> +    char *p = buffer;
> +
> +    snprintf(buffer, sizeof(buffer), "0x%"PRIx64",0x%"PRIx64",%d",
> +             interval->low, interval->high, interval->type);
> +
> +    visit_type_str(v, name, &p, errp);
> +}
> +
> +static void set_interval(Object *obj, Visitor *v, const char *name,
> +                         void *opaque, Error **errp)
> +{
> +    DeviceState *dev = DEVICE(obj);
> +    Property *prop = opaque;
> +    Interval *interval = qdev_get_prop_ptr(dev, prop);
> +    Error *local_err = NULL;
> +    unsigned int type;
> +    gchar **fields;
> +    uint64_t addr;
> +    char *str;
> +    int ret;
> +
> +    if (dev->realized) {
> +        qdev_prop_set_after_realize(dev, name, errp);
> +        return;
> +    }
> +
> +    visit_type_str(v, name, &str, &local_err);
> +    if (local_err) {
> +        error_propagate(errp, local_err);
> +        return;
> +    }
> +
> +    fields = g_strsplit(str, ",", 3);
> +
> +    ret = qemu_strtou64(fields[0], NULL, 16, &addr);
> +    if (!ret) {
> +        interval->low = addr;
> +    } else {
> +        error_setg(errp, "Failed to decode interval low addr");
> +        error_append_hint(errp,
> +                          "should be an address in hexa with 0x prefix\n");
> +        goto out;
> +    }
> +
> +    ret = qemu_strtou64(fields[1], NULL, 16, &addr);
> +    if (!ret) {
> +        interval->high = addr;
> +    } else {
> +        error_setg(errp, "Failed to decode interval high addr");
> +        error_append_hint(errp,
> +                          "should be an address in hexa with 0x prefix\n");
> +        goto out;
> +    }
> +
> +    ret = qemu_strtoui(fields[2], NULL, 10, &type);
> +    if (!ret) {
> +        interval->type = type;
> +    } else {
> +        error_setg(errp, "Failed to decode interval type");
> +        error_append_hint(errp, "should be an unsigned int in decimal\n");
> +    }
> +out:
> +    g_free(str);
> +    g_strfreev(fields);
> +    return;
> +}
> +
> +const PropertyInfo qdev_prop_interval = {
> +    .name  = "labelled_interval",
> +    .description = "Labelled interval, example: 0xFEE00000,0xFEEFFFFF,0",
> +    .get   = get_interval,
> +    .set   = set_interval,
> +};
> +
>  /* --- on/off/auto --- */
>  
>  const PropertyInfo qdev_prop_on_off_auto = {
> diff --git a/include/exec/memory.h b/include/exec/memory.h
> index e499dc215b..e238d1c352 100644
> --- a/include/exec/memory.h
> +++ b/include/exec/memory.h
> @@ -57,6 +57,12 @@ struct MemoryRegionMmio {
>      CPUWriteMemoryFunc *write[3];
>  };
>  
> +struct Interval {
> +    hwaddr low;
> +    hwaddr high;
> +    unsigned int type;
> +};
> +

Just an observation that 'Interval' is a very generic name.
We've got 'AddrRange' but that's Int128.

Dave

>  typedef struct IOMMUTLBEntry IOMMUTLBEntry;
>  
>  /* See address_space_translate: bit 0 is read, bit 1 is write.  */
> diff --git a/include/hw/qdev-properties.h b/include/hw/qdev-properties.h
> index c6a8cb5516..2ba7c8711b 100644
> --- a/include/hw/qdev-properties.h
> +++ b/include/hw/qdev-properties.h
> @@ -20,6 +20,7 @@ extern const PropertyInfo qdev_prop_chr;
>  extern const PropertyInfo qdev_prop_tpm;
>  extern const PropertyInfo qdev_prop_ptr;
>  extern const PropertyInfo qdev_prop_macaddr;
> +extern const PropertyInfo qdev_prop_interval;
>  extern const PropertyInfo qdev_prop_on_off_auto;
>  extern const PropertyInfo qdev_prop_losttickpolicy;
>  extern const PropertyInfo qdev_prop_blockdev_on_error;
> @@ -202,6 +203,8 @@ extern const PropertyInfo qdev_prop_pcie_link_width;
>      DEFINE_PROP(_n, _s, _f, qdev_prop_drive_iothread, BlockBackend *)
>  #define DEFINE_PROP_MACADDR(_n, _s, _f)         \
>      DEFINE_PROP(_n, _s, _f, qdev_prop_macaddr, MACAddr)
> +#define DEFINE_PROP_INTERVAL(_n, _s, _f)         \
> +    DEFINE_PROP(_n, _s, _f, qdev_prop_interval, Interval)
>  #define DEFINE_PROP_ON_OFF_AUTO(_n, _s, _f, _d) \
>      DEFINE_PROP_SIGNED(_n, _s, _f, _d, qdev_prop_on_off_auto, OnOffAuto)
>  #define DEFINE_PROP_LOSTTICKPOLICY(_n, _s, _f, _d) \
> diff --git a/include/qemu/typedefs.h b/include/qemu/typedefs.h
> index 375770a80f..a827c9a3fe 100644
> --- a/include/qemu/typedefs.h
> +++ b/include/qemu/typedefs.h
> @@ -58,6 +58,7 @@ typedef struct ISABus ISABus;
>  typedef struct ISADevice ISADevice;
>  typedef struct IsaDma IsaDma;
>  typedef struct MACAddr MACAddr;
> +typedef struct Interval Interval;
>  typedef struct MachineClass MachineClass;
>  typedef struct MachineState MachineState;
>  typedef struct MemoryListener MemoryListener;
> -- 
> 2.20.1
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
Auger Eric Nov. 25, 2019, 1:12 p.m. UTC | #2
Hi Dave,

On 11/22/19 8:03 PM, Dr. David Alan Gilbert wrote:
> * Eric Auger (eric.auger@redhat.com) wrote:
>> Introduce a new property defining a labelled interval:
>> <low address>,<high address>,label.
>>
>> This will be used to encode reserved IOVA regions. The label
>> is left undefined to ease reuse accross use cases.
>>
>> For instance, in virtio-iommu use case, reserved IOVA regions
>> will be passed by the machine code to the virtio-iommu-pci
>> device (an array of those). The label will match the
>> virtio_iommu_probe_resv_mem subtype value:
>> - VIRTIO_IOMMU_RESV_MEM_T_RESERVED (0)
>> - VIRTIO_IOMMU_RESV_MEM_T_MSI (1)
>>
>> This is used to inform the virtio-iommu-pci device it should
>> bypass the MSI region: 0xfee00000, 0xfeefffff, 1.
>>
>> Signed-off-by: Eric Auger <eric.auger@redhat.com>
>> ---
>>  hw/core/qdev-properties.c    | 90 ++++++++++++++++++++++++++++++++++++
>>  include/exec/memory.h        |  6 +++
>>  include/hw/qdev-properties.h |  3 ++
>>  include/qemu/typedefs.h      |  1 +
>>  4 files changed, 100 insertions(+)
>>
>> diff --git a/hw/core/qdev-properties.c b/hw/core/qdev-properties.c
>> index ac28890e5a..8d70f34e37 100644
>> --- a/hw/core/qdev-properties.c
>> +++ b/hw/core/qdev-properties.c
>> @@ -13,6 +13,7 @@
>>  #include "qapi/visitor.h"
>>  #include "chardev/char.h"
>>  #include "qemu/uuid.h"
>> +#include "qemu/cutils.h"
>>  
>>  void qdev_prop_set_after_realize(DeviceState *dev, const char *name,
>>                                    Error **errp)
>> @@ -585,6 +586,95 @@ const PropertyInfo qdev_prop_macaddr = {
>>      .set   = set_mac,
>>  };
>>  
>> +/* --- Labelled Interval --- */
>> +
>> +/*
>> + * accepted syntax versions:
>> + *   <low address>,<high address>,<type>
>> + *   where low/high addresses are uint64_t in hexa (feat. 0x prefix)
>> + *   and type is an unsigned integer
>> + */
>> +static void get_interval(Object *obj, Visitor *v, const char *name,
>> +                         void *opaque, Error **errp)
>> +{
>> +    DeviceState *dev = DEVICE(obj);
>> +    Property *prop = opaque;
>> +    Interval *interval = qdev_get_prop_ptr(dev, prop);
>> +    char buffer[64];
>> +    char *p = buffer;
>> +
>> +    snprintf(buffer, sizeof(buffer), "0x%"PRIx64",0x%"PRIx64",%d",
>> +             interval->low, interval->high, interval->type);
>> +
>> +    visit_type_str(v, name, &p, errp);
>> +}
>> +
>> +static void set_interval(Object *obj, Visitor *v, const char *name,
>> +                         void *opaque, Error **errp)
>> +{
>> +    DeviceState *dev = DEVICE(obj);
>> +    Property *prop = opaque;
>> +    Interval *interval = qdev_get_prop_ptr(dev, prop);
>> +    Error *local_err = NULL;
>> +    unsigned int type;
>> +    gchar **fields;
>> +    uint64_t addr;
>> +    char *str;
>> +    int ret;
>> +
>> +    if (dev->realized) {
>> +        qdev_prop_set_after_realize(dev, name, errp);
>> +        return;
>> +    }
>> +
>> +    visit_type_str(v, name, &str, &local_err);
>> +    if (local_err) {
>> +        error_propagate(errp, local_err);
>> +        return;
>> +    }
>> +
>> +    fields = g_strsplit(str, ",", 3);
>> +
>> +    ret = qemu_strtou64(fields[0], NULL, 16, &addr);
>> +    if (!ret) {
>> +        interval->low = addr;
>> +    } else {
>> +        error_setg(errp, "Failed to decode interval low addr");
>> +        error_append_hint(errp,
>> +                          "should be an address in hexa with 0x prefix\n");
>> +        goto out;
>> +    }
>> +
>> +    ret = qemu_strtou64(fields[1], NULL, 16, &addr);
>> +    if (!ret) {
>> +        interval->high = addr;
>> +    } else {
>> +        error_setg(errp, "Failed to decode interval high addr");
>> +        error_append_hint(errp,
>> +                          "should be an address in hexa with 0x prefix\n");
>> +        goto out;
>> +    }
>> +
>> +    ret = qemu_strtoui(fields[2], NULL, 10, &type);
>> +    if (!ret) {
>> +        interval->type = type;
>> +    } else {
>> +        error_setg(errp, "Failed to decode interval type");
>> +        error_append_hint(errp, "should be an unsigned int in decimal\n");
>> +    }
>> +out:
>> +    g_free(str);
>> +    g_strfreev(fields);
>> +    return;
>> +}
>> +
>> +const PropertyInfo qdev_prop_interval = {
>> +    .name  = "labelled_interval",
>> +    .description = "Labelled interval, example: 0xFEE00000,0xFEEFFFFF,0",
>> +    .get   = get_interval,
>> +    .set   = set_interval,
>> +};
>> +
>>  /* --- on/off/auto --- */
>>  
>>  const PropertyInfo qdev_prop_on_off_auto = {
>> diff --git a/include/exec/memory.h b/include/exec/memory.h
>> index e499dc215b..e238d1c352 100644
>> --- a/include/exec/memory.h
>> +++ b/include/exec/memory.h
>> @@ -57,6 +57,12 @@ struct MemoryRegionMmio {
>>      CPUWriteMemoryFunc *write[3];
>>  };
>>  
>> +struct Interval {
>> +    hwaddr low;
>> +    hwaddr high;
>> +    unsigned int type;
>> +};
>> +
> 
> Just an observation that 'Interval' is a very generic name.
> We've got 'AddrRange' but that's Int128.
As it is defined in memory.h it may make sense to rename it
ReservedRegion then?

Thanks

Eric

> 
> Dave
> 
>>  typedef struct IOMMUTLBEntry IOMMUTLBEntry;
>>  
>>  /* See address_space_translate: bit 0 is read, bit 1 is write.  */
>> diff --git a/include/hw/qdev-properties.h b/include/hw/qdev-properties.h
>> index c6a8cb5516..2ba7c8711b 100644
>> --- a/include/hw/qdev-properties.h
>> +++ b/include/hw/qdev-properties.h
>> @@ -20,6 +20,7 @@ extern const PropertyInfo qdev_prop_chr;
>>  extern const PropertyInfo qdev_prop_tpm;
>>  extern const PropertyInfo qdev_prop_ptr;
>>  extern const PropertyInfo qdev_prop_macaddr;
>> +extern const PropertyInfo qdev_prop_interval;
>>  extern const PropertyInfo qdev_prop_on_off_auto;
>>  extern const PropertyInfo qdev_prop_losttickpolicy;
>>  extern const PropertyInfo qdev_prop_blockdev_on_error;
>> @@ -202,6 +203,8 @@ extern const PropertyInfo qdev_prop_pcie_link_width;
>>      DEFINE_PROP(_n, _s, _f, qdev_prop_drive_iothread, BlockBackend *)
>>  #define DEFINE_PROP_MACADDR(_n, _s, _f)         \
>>      DEFINE_PROP(_n, _s, _f, qdev_prop_macaddr, MACAddr)
>> +#define DEFINE_PROP_INTERVAL(_n, _s, _f)         \
>> +    DEFINE_PROP(_n, _s, _f, qdev_prop_interval, Interval)
>>  #define DEFINE_PROP_ON_OFF_AUTO(_n, _s, _f, _d) \
>>      DEFINE_PROP_SIGNED(_n, _s, _f, _d, qdev_prop_on_off_auto, OnOffAuto)
>>  #define DEFINE_PROP_LOSTTICKPOLICY(_n, _s, _f, _d) \
>> diff --git a/include/qemu/typedefs.h b/include/qemu/typedefs.h
>> index 375770a80f..a827c9a3fe 100644
>> --- a/include/qemu/typedefs.h
>> +++ b/include/qemu/typedefs.h
>> @@ -58,6 +58,7 @@ typedef struct ISABus ISABus;
>>  typedef struct ISADevice ISADevice;
>>  typedef struct IsaDma IsaDma;
>>  typedef struct MACAddr MACAddr;
>> +typedef struct Interval Interval;
>>  typedef struct MachineClass MachineClass;
>>  typedef struct MachineState MachineState;
>>  typedef struct MemoryListener MemoryListener;
>> -- 
>> 2.20.1
>>
> --
> Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK
>
Markus Armbruster Dec. 12, 2019, 12:17 p.m. UTC | #3
Eric Auger <eric.auger@redhat.com> writes:

> Introduce a new property defining a labelled interval:
> <low address>,<high address>,label.
>
> This will be used to encode reserved IOVA regions. The label
> is left undefined to ease reuse accross use cases.

What does the last sentence mean?

> For instance, in virtio-iommu use case, reserved IOVA regions
> will be passed by the machine code to the virtio-iommu-pci
> device (an array of those). The label will match the
> virtio_iommu_probe_resv_mem subtype value:
> - VIRTIO_IOMMU_RESV_MEM_T_RESERVED (0)
> - VIRTIO_IOMMU_RESV_MEM_T_MSI (1)
>
> This is used to inform the virtio-iommu-pci device it should
> bypass the MSI region: 0xfee00000, 0xfeefffff, 1.

So the "label" part of "<low address>,<high address>,label" is a number?

Is a number appropriate for your use case, or would an enum be better?

>
> Signed-off-by: Eric Auger <eric.auger@redhat.com> ---
>hw/core/qdev-properties.c | 90 ++++++++++++++++++++++++++++++++++++
>include/exec/memory.h | 6 +++ include/hw/qdev-properties.h | 3 ++
>include/qemu/typedefs.h | 1 + 4 files changed, 100 insertions(+)

Subject has 'qapi:', but it's actually about qdev.  Please adjust the subject.

> diff --git a/hw/core/qdev-properties.c b/hw/core/qdev-properties.c
> index ac28890e5a..8d70f34e37 100644
> --- a/hw/core/qdev-properties.c
> +++ b/hw/core/qdev-properties.c
> @@ -13,6 +13,7 @@
>  #include "qapi/visitor.h"
>  #include "chardev/char.h"
>  #include "qemu/uuid.h"
> +#include "qemu/cutils.h"
>  
>  void qdev_prop_set_after_realize(DeviceState *dev, const char *name,
>                                    Error **errp)
> @@ -585,6 +586,95 @@ const PropertyInfo qdev_prop_macaddr = {
>      .set   = set_mac,
>  };
>  
> +/* --- Labelled Interval --- */
> +
> +/*
> + * accepted syntax versions:

"versions"?

> + *   <low address>,<high address>,<type>
> + *   where low/high addresses are uint64_t in hexa (feat. 0x prefix)

"hexa" is not a word.

I'm afraid I don't get the parenthesis.

> + *   and type is an unsigned integer
> + */
> +static void get_interval(Object *obj, Visitor *v, const char *name,
> +                         void *opaque, Error **errp)
> +{
> +    DeviceState *dev = DEVICE(obj);
> +    Property *prop = opaque;
> +    Interval *interval = qdev_get_prop_ptr(dev, prop);
> +    char buffer[64];
> +    char *p = buffer;
> +
> +    Snprintf(buffer, sizeof(buffer), "0x%"PRIx64",0x%"PRIx64",%d",
> +             interval->low, interval->high, interval->type);

interval->type is unsigned.  Use %u, not %d.

> +
> +    visit_type_str(v, name, &p, errp);
> +}
> +
> +static void set_interval(Object *obj, Visitor *v, const char *name,
> +                         void *opaque, Error **errp)
> +{
> +    DeviceState *dev = DEVICE(obj);
> +    Property *prop = opaque;
> +    Interval *interval = qdev_get_prop_ptr(dev, prop);
> +    Error *local_err = NULL;
> +    unsigned int type;
> +    gchar **fields;
> +    uint64_t addr;
> +    char *str;
> +    int ret;
> +
> +    if (dev->realized) {
> +        qdev_prop_set_after_realize(dev, name, errp);
> +        return;
> +    }
> +
> +    visit_type_str(v, name, &str, &local_err);
> +    if (local_err) {
> +        error_propagate(errp, local_err);
> +        return;
> +    }
> +
> +    fields = g_strsplit(str, ",", 3);
> +
> +    ret = qemu_strtou64(fields[0], NULL, 16, &addr);

Aha, the 0x prefix is actually optional.

> +    if (!ret) {
> +        interval->low = addr;
> +    } else {
> +        error_setg(errp, "Failed to decode interval low addr");
> +        error_append_hint(errp,
> +                          "should be an address in hexa with 0x prefix\n");

"hexa" is not a word, and the 0x prefix is actually optional.

> +        goto out;
> +    }

I prefer

       if (error) {
           handle error
           bail out
       }
       handle success

over

       if (success) {
           handle success
       if (error) {
           handle error
           bail out
       }

In this case:

       if (ret) {
           error_setg(errp, "Failed to decode interval low addr");
           error_append_hint(errp,
                             "should be an address in hexa with 0x prefix\n");
           goto out;
       }
       interval->low = addr;


> +
> +    ret = qemu_strtou64(fields[1], NULL, 16, &addr);

Crash if @str doesn't contain ',', because the g_strsplit(str, ",", 3)
yields { [0] = str, NULL }.

> +    if (!ret) {
> +        interval->high = addr;
> +    } else {
> +        error_setg(errp, "Failed to decode interval high addr");
> +        error_append_hint(errp,
> +                          "should be an address in hexa with 0x prefix\n");
> +        goto out;
> +    }
> +
> +    ret = qemu_strtoui(fields[2], NULL, 10, &type);

Likewise, crash if @str contains only one ','.

I wouldn't use g_strsplit() here.  After

    ret = qemu_strtoui(str, &endptr, 16, &interval->low);

@endptr points behind the address.  So:

    if (ret || *endptr != ',') {
        handle error ...
        goto out
    }

    ret = qemu_strtoui(endptr + 1, &endptr, 16, &interval->high);

and so forth.

Note that the if (ret || *endptr != ',') checks for two distinct errors.
Distinct error messages might be more helpful.

> +    if (!ret) {
> +        interval->type = type;
> +    } else {
> +        error_setg(errp, "Failed to decode interval type");
> +        error_append_hint(errp, "should be an unsigned int in decimal\n");
> +    }
> +out:
> +    g_free(str);
> +    g_strfreev(fields);
> +    return;
> +}
> +
> +const PropertyInfo qdev_prop_interval = {
> +    .name  = "labelled_interval",
> +    .description = "Labelled interval, example: 0xFEE00000,0xFEEFFFFF,0",
> +    .get   = get_interval,
> +    .set   = set_interval,
> +};
> +
>  /* --- on/off/auto --- */
>  
>  const PropertyInfo qdev_prop_on_off_auto = {
> diff --git a/include/exec/memory.h b/include/exec/memory.h
> index e499dc215b..e238d1c352 100644
> --- a/include/exec/memory.h
> +++ b/include/exec/memory.h
> @@ -57,6 +57,12 @@ struct MemoryRegionMmio {
>      CPUWriteMemoryFunc *write[3];
>  };
>  
> +struct Interval {
> +    hwaddr low;
> +    hwaddr high;
> +    unsigned int type;
> +};

This isn't an interval.  An interval consists of two values, not three.

The third one is called "type" here, and "label" elsewhere.  Pick one
and stick to it.

Then pick a name for the triple.  Elsewhere, you call it "labelled
interval".

> +
>  typedef struct IOMMUTLBEntry IOMMUTLBEntry;
>  
>  /* See address_space_translate: bit 0 is read, bit 1 is write.  */
> diff --git a/include/hw/qdev-properties.h b/include/hw/qdev-properties.h
> index c6a8cb5516..2ba7c8711b 100644
> --- a/include/hw/qdev-properties.h
> +++ b/include/hw/qdev-properties.h
> @@ -20,6 +20,7 @@ extern const PropertyInfo qdev_prop_chr;
>  extern const PropertyInfo qdev_prop_tpm;
>  extern const PropertyInfo qdev_prop_ptr;
>  extern const PropertyInfo qdev_prop_macaddr;
> +extern const PropertyInfo qdev_prop_interval;
>  extern const PropertyInfo qdev_prop_on_off_auto;
>  extern const PropertyInfo qdev_prop_losttickpolicy;
>  extern const PropertyInfo qdev_prop_blockdev_on_error;
> @@ -202,6 +203,8 @@ extern const PropertyInfo qdev_prop_pcie_link_width;
>      DEFINE_PROP(_n, _s, _f, qdev_prop_drive_iothread, BlockBackend *)
>  #define DEFINE_PROP_MACADDR(_n, _s, _f)         \
>      DEFINE_PROP(_n, _s, _f, qdev_prop_macaddr, MACAddr)
> +#define DEFINE_PROP_INTERVAL(_n, _s, _f)         \
> +    DEFINE_PROP(_n, _s, _f, qdev_prop_interval, Interval)
>  #define DEFINE_PROP_ON_OFF_AUTO(_n, _s, _f, _d) \
>      DEFINE_PROP_SIGNED(_n, _s, _f, _d, qdev_prop_on_off_auto, OnOffAuto)
>  #define DEFINE_PROP_LOSTTICKPOLICY(_n, _s, _f, _d) \
> diff --git a/include/qemu/typedefs.h b/include/qemu/typedefs.h
> index 375770a80f..a827c9a3fe 100644
> --- a/include/qemu/typedefs.h
> +++ b/include/qemu/typedefs.h
> @@ -58,6 +58,7 @@ typedef struct ISABus ISABus;
>  typedef struct ISADevice ISADevice;
>  typedef struct IsaDma IsaDma;
>  typedef struct MACAddr MACAddr;
> +typedef struct Interval Interval;
>  typedef struct MachineClass MachineClass;
>  typedef struct MachineState MachineState;
>  typedef struct MemoryListener MemoryListener;
Auger Eric Dec. 12, 2019, 3:13 p.m. UTC | #4
Hi Markus,

On 12/12/19 1:17 PM, Markus Armbruster wrote:
> Eric Auger <eric.auger@redhat.com> writes:
> 
>> Introduce a new property defining a labelled interval:
>> <low address>,<high address>,label.
>>
>> This will be used to encode reserved IOVA regions. The label
>> is left undefined to ease reuse accross use cases.
> 
> What does the last sentence mean?
The dilemma was shall I specialize this property such as ReservedRegion
or shall I leave it generic enough to serve somebody else use case. I
first chose the latter but now I think I should rather call it something
like ReservedRegion as in any case it has addresses and an integer label.
> 
>> For instance, in virtio-iommu use case, reserved IOVA regions
>> will be passed by the machine code to the virtio-iommu-pci
>> device (an array of those). The label will match the
>> virtio_iommu_probe_resv_mem subtype value:
>> - VIRTIO_IOMMU_RESV_MEM_T_RESERVED (0)
>> - VIRTIO_IOMMU_RESV_MEM_T_MSI (1)
>>
>> This is used to inform the virtio-iommu-pci device it should
>> bypass the MSI region: 0xfee00000, 0xfeefffff, 1.
> 
> So the "label" part of "<low address>,<high address>,label" is a number?
yes it is.
> 
> Is a number appropriate for your use case, or would an enum be better?
I think a number is OK. There might be other types of reserved regions
in the future. Also if we want to allow somebody else to reuse that
property in another context, I would rather leave it open?
> 
>>
>> Signed-off-by: Eric Auger <eric.auger@redhat.com> ---
>> hw/core/qdev-properties.c | 90 ++++++++++++++++++++++++++++++++++++
>> include/exec/memory.h | 6 +++ include/hw/qdev-properties.h | 3 ++
>> include/qemu/typedefs.h | 1 + 4 files changed, 100 insertions(+)
> 
> Subject has 'qapi:', but it's actually about qdev.  Please adjust the subject.
OK
> 
>> diff --git a/hw/core/qdev-properties.c b/hw/core/qdev-properties.c
>> index ac28890e5a..8d70f34e37 100644
>> --- a/hw/core/qdev-properties.c
>> +++ b/hw/core/qdev-properties.c
>> @@ -13,6 +13,7 @@
>>  #include "qapi/visitor.h"
>>  #include "chardev/char.h"
>>  #include "qemu/uuid.h"
>> +#include "qemu/cutils.h"
>>  
>>  void qdev_prop_set_after_realize(DeviceState *dev, const char *name,
>>                                    Error **errp)
>> @@ -585,6 +586,95 @@ const PropertyInfo qdev_prop_macaddr = {
>>      .set   = set_mac,
>>  };
>>  
>> +/* --- Labelled Interval --- */
>> +
>> +/*
>> + * accepted syntax versions:
> 
> "versions"?
s/versions/version
> 
>> + *   <low address>,<high address>,<type>
>> + *   where low/high addresses are uint64_t in hexa (feat. 0x prefix)
> 
> "hexa" is not a word.
OK
> 
> I'm afraid I don't get the parenthesis.
I wanted to mention the 0x prefix was needed but as you mentionned below
it is not needed actually.
> 
>> + *   and type is an unsigned integer
>> + */
>> +static void get_interval(Object *obj, Visitor *v, const char *name,
>> +                         void *opaque, Error **errp)
>> +{
>> +    DeviceState *dev = DEVICE(obj);
>> +    Property *prop = opaque;
>> +    Interval *interval = qdev_get_prop_ptr(dev, prop);
>> +    char buffer[64];
>> +    char *p = buffer;
>> +
>> +    Snprintf(buffer, sizeof(buffer), "0x%"PRIx64",0x%"PRIx64",%d",
>> +             interval->low, interval->high, interval->type);
> 
> interval->type is unsigned.  Use %u, not %d.
OK
> 
>> +
>> +    visit_type_str(v, name, &p, errp);
>> +}
>> +
>> +static void set_interval(Object *obj, Visitor *v, const char *name,
>> +                         void *opaque, Error **errp)
>> +{
>> +    DeviceState *dev = DEVICE(obj);
>> +    Property *prop = opaque;
>> +    Interval *interval = qdev_get_prop_ptr(dev, prop);
>> +    Error *local_err = NULL;
>> +    unsigned int type;
>> +    gchar **fields;
>> +    uint64_t addr;
>> +    char *str;
>> +    int ret;
>> +
>> +    if (dev->realized) {
>> +        qdev_prop_set_after_realize(dev, name, errp);
>> +        return;
>> +    }
>> +
>> +    visit_type_str(v, name, &str, &local_err);
>> +    if (local_err) {
>> +        error_propagate(errp, local_err);
>> +        return;
>> +    }
>> +
>> +    fields = g_strsplit(str, ",", 3);
>> +
>> +    ret = qemu_strtou64(fields[0], NULL, 16, &addr);
> 
> Aha, the 0x prefix is actually optional.
> 
>> +    if (!ret) {
>> +        interval->low = addr;
>> +    } else {
>> +        error_setg(errp, "Failed to decode interval low addr");
>> +        error_append_hint(errp,
>> +                          "should be an address in hexa with 0x prefix\n");
> 
> "hexa" is not a word, and the 0x prefix is actually optional.
OK
> 
>> +        goto out;
>> +    }
> 
> I prefer
> 
>        if (error) {
>            handle error
>            bail out
>        }
>        handle success
> 
> over
> 
>        if (success) {
>            handle success
>        if (error) {
>            handle error
>            bail out
>        }
> 
> In this case:
> 
>        if (ret) {
>            error_setg(errp, "Failed to decode interval low addr");
>            error_append_hint(errp,
>                              "should be an address in hexa with 0x prefix\n");
>            goto out;
>        }
>        interval->low = addr;
OK
> 
> 
>> +
>> +    ret = qemu_strtou64(fields[1], NULL, 16, &addr);
> 
> Crash if @str doesn't contain ',', because the g_strsplit(str, ",", 3)
> yields { [0] = str, NULL }.
> 
>> +    if (!ret) {
>> +        interval->high = addr;
>> +    } else {
>> +        error_setg(errp, "Failed to decode interval high addr");
>> +        error_append_hint(errp,
>> +                          "should be an address in hexa with 0x prefix\n");
>> +        goto out;
>> +    }
>> +
>> +    ret = qemu_strtoui(fields[2], NULL, 10, &type);
> 
> Likewise, crash if @str contains only one ','.
> 
> I wouldn't use g_strsplit() here.  After
> 
>     ret = qemu_strtoui(str, &endptr, 16, &interval->low);
> 
> @endptr points behind the address.  So:
> 
>     if (ret || *endptr != ',') {
>         handle error ...
>         goto out
>     }
> 
>     ret = qemu_strtoui(endptr + 1, &endptr, 16, &interval->high);
> 
> and so forth.
> 
> Note that the if (ret || *endptr != ',') checks for two distinct errors.
> Distinct error messages might be more helpful.
OK I will revisit that.
> 
>> +    if (!ret) {
>> +        interval->type = type;
>> +    } else {
>> +        error_setg(errp, "Failed to decode interval type");
>> +        error_append_hint(errp, "should be an unsigned int in decimal\n");
>> +    }
>> +out:
>> +    g_free(str);
>> +    g_strfreev(fields);
>> +    return;
>> +}
>> +
>> +const PropertyInfo qdev_prop_interval = {
>> +    .name  = "labelled_interval",
>> +    .description = "Labelled interval, example: 0xFEE00000,0xFEEFFFFF,0",
>> +    .get   = get_interval,
>> +    .set   = set_interval,
>> +};
>> +
>>  /* --- on/off/auto --- */
>>  
>>  const PropertyInfo qdev_prop_on_off_auto = {
>> diff --git a/include/exec/memory.h b/include/exec/memory.h
>> index e499dc215b..e238d1c352 100644
>> --- a/include/exec/memory.h
>> +++ b/include/exec/memory.h
>> @@ -57,6 +57,12 @@ struct MemoryRegionMmio {
>>      CPUWriteMemoryFunc *write[3];
>>  };
>>  
>> +struct Interval {
>> +    hwaddr low;
>> +    hwaddr high;
>> +    unsigned int type;
>> +};
> 
> This isn't an interval.  An interval consists of two values, not three.
> 
> The third one is called "type" here, and "label" elsewhere.  Pick one
> and stick to it.
> 
> Then pick a name for the triple.  Elsewhere, you call it "labelled
> interval".
I would tend to use ReservedRegion now if nobody objects.

Thank you for the review!


Eric
> 
>> +
>>  typedef struct IOMMUTLBEntry IOMMUTLBEntry;
>>  
>>  /* See address_space_translate: bit 0 is read, bit 1 is write.  */
>> diff --git a/include/hw/qdev-properties.h b/include/hw/qdev-properties.h
>> index c6a8cb5516..2ba7c8711b 100644
>> --- a/include/hw/qdev-properties.h
>> +++ b/include/hw/qdev-properties.h
>> @@ -20,6 +20,7 @@ extern const PropertyInfo qdev_prop_chr;
>>  extern const PropertyInfo qdev_prop_tpm;
>>  extern const PropertyInfo qdev_prop_ptr;
>>  extern const PropertyInfo qdev_prop_macaddr;
>> +extern const PropertyInfo qdev_prop_interval;
>>  extern const PropertyInfo qdev_prop_on_off_auto;
>>  extern const PropertyInfo qdev_prop_losttickpolicy;
>>  extern const PropertyInfo qdev_prop_blockdev_on_error;
>> @@ -202,6 +203,8 @@ extern const PropertyInfo qdev_prop_pcie_link_width;
>>      DEFINE_PROP(_n, _s, _f, qdev_prop_drive_iothread, BlockBackend *)
>>  #define DEFINE_PROP_MACADDR(_n, _s, _f)         \
>>      DEFINE_PROP(_n, _s, _f, qdev_prop_macaddr, MACAddr)
>> +#define DEFINE_PROP_INTERVAL(_n, _s, _f)         \
>> +    DEFINE_PROP(_n, _s, _f, qdev_prop_interval, Interval)
>>  #define DEFINE_PROP_ON_OFF_AUTO(_n, _s, _f, _d) \
>>      DEFINE_PROP_SIGNED(_n, _s, _f, _d, qdev_prop_on_off_auto, OnOffAuto)
>>  #define DEFINE_PROP_LOSTTICKPOLICY(_n, _s, _f, _d) \
>> diff --git a/include/qemu/typedefs.h b/include/qemu/typedefs.h
>> index 375770a80f..a827c9a3fe 100644
>> --- a/include/qemu/typedefs.h
>> +++ b/include/qemu/typedefs.h
>> @@ -58,6 +58,7 @@ typedef struct ISABus ISABus;
>>  typedef struct ISADevice ISADevice;
>>  typedef struct IsaDma IsaDma;
>>  typedef struct MACAddr MACAddr;
>> +typedef struct Interval Interval;
>>  typedef struct MachineClass MachineClass;
>>  typedef struct MachineState MachineState;
>>  typedef struct MemoryListener MemoryListener;
> 
>
Markus Armbruster Dec. 13, 2019, 10:03 a.m. UTC | #5
Auger Eric <eric.auger@redhat.com> writes:

> Hi Markus,
>
> On 12/12/19 1:17 PM, Markus Armbruster wrote:
>> Eric Auger <eric.auger@redhat.com> writes:
>> 
>>> Introduce a new property defining a labelled interval:
>>> <low address>,<high address>,label.
>>>
>>> This will be used to encode reserved IOVA regions. The label
>>> is left undefined to ease reuse accross use cases.
>> 
>> What does the last sentence mean?
> The dilemma was shall I specialize this property such as ReservedRegion
> or shall I leave it generic enough to serve somebody else use case. I
> first chose the latter but now I think I should rather call it something
> like ReservedRegion as in any case it has addresses and an integer label.
>> 
>>> For instance, in virtio-iommu use case, reserved IOVA regions
>>> will be passed by the machine code to the virtio-iommu-pci
>>> device (an array of those). The label will match the
>>> virtio_iommu_probe_resv_mem subtype value:
>>> - VIRTIO_IOMMU_RESV_MEM_T_RESERVED (0)
>>> - VIRTIO_IOMMU_RESV_MEM_T_MSI (1)
>>>
>>> This is used to inform the virtio-iommu-pci device it should
>>> bypass the MSI region: 0xfee00000, 0xfeefffff, 1.
>> 
>> So the "label" part of "<low address>,<high address>,label" is a number?
> yes it is.
>> 
>> Is a number appropriate for your use case, or would an enum be better?
> I think a number is OK. There might be other types of reserved regions
> in the future. Also if we want to allow somebody else to reuse that
> property in another context, I would rather leave it open?

I'd prioritize the user interface over possible reuse (which might never
happen).  Mind, I'm not telling you using numbers is a bad user
interface.  In general, enums are nicer, but I don't know enough about
this particular case.

>> 
>>>
>>> Signed-off-by: Eric Auger <eric.auger@redhat.com> ---
[...]
>>> diff --git a/include/exec/memory.h b/include/exec/memory.h
>>> index e499dc215b..e238d1c352 100644
>>> --- a/include/exec/memory.h
>>> +++ b/include/exec/memory.h
>>> @@ -57,6 +57,12 @@ struct MemoryRegionMmio {
>>>      CPUWriteMemoryFunc *write[3];
>>>  };
>>>  
>>> +struct Interval {
>>> +    hwaddr low;
>>> +    hwaddr high;
>>> +    unsigned int type;
>>> +};
>> 
>> This isn't an interval.  An interval consists of two values, not three.
>> 
>> The third one is called "type" here, and "label" elsewhere.  Pick one
>> and stick to it.
>> 
>> Then pick a name for the triple.  Elsewhere, you call it "labelled
>> interval".
> I would tend to use ReservedRegion now if nobody objects.

Sounds good to me.

> Thank you for the review!

You're welcome!

Patch
diff mbox series

diff --git a/hw/core/qdev-properties.c b/hw/core/qdev-properties.c
index ac28890e5a..8d70f34e37 100644
--- a/hw/core/qdev-properties.c
+++ b/hw/core/qdev-properties.c
@@ -13,6 +13,7 @@ 
 #include "qapi/visitor.h"
 #include "chardev/char.h"
 #include "qemu/uuid.h"
+#include "qemu/cutils.h"
 
 void qdev_prop_set_after_realize(DeviceState *dev, const char *name,
                                   Error **errp)
@@ -585,6 +586,95 @@  const PropertyInfo qdev_prop_macaddr = {
     .set   = set_mac,
 };
 
+/* --- Labelled Interval --- */
+
+/*
+ * accepted syntax versions:
+ *   <low address>,<high address>,<type>
+ *   where low/high addresses are uint64_t in hexa (feat. 0x prefix)
+ *   and type is an unsigned integer
+ */
+static void get_interval(Object *obj, Visitor *v, const char *name,
+                         void *opaque, Error **errp)
+{
+    DeviceState *dev = DEVICE(obj);
+    Property *prop = opaque;
+    Interval *interval = qdev_get_prop_ptr(dev, prop);
+    char buffer[64];
+    char *p = buffer;
+
+    snprintf(buffer, sizeof(buffer), "0x%"PRIx64",0x%"PRIx64",%d",
+             interval->low, interval->high, interval->type);
+
+    visit_type_str(v, name, &p, errp);
+}
+
+static void set_interval(Object *obj, Visitor *v, const char *name,
+                         void *opaque, Error **errp)
+{
+    DeviceState *dev = DEVICE(obj);
+    Property *prop = opaque;
+    Interval *interval = qdev_get_prop_ptr(dev, prop);
+    Error *local_err = NULL;
+    unsigned int type;
+    gchar **fields;
+    uint64_t addr;
+    char *str;
+    int ret;
+
+    if (dev->realized) {
+        qdev_prop_set_after_realize(dev, name, errp);
+        return;
+    }
+
+    visit_type_str(v, name, &str, &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
+        return;
+    }
+
+    fields = g_strsplit(str, ",", 3);
+
+    ret = qemu_strtou64(fields[0], NULL, 16, &addr);
+    if (!ret) {
+        interval->low = addr;
+    } else {
+        error_setg(errp, "Failed to decode interval low addr");
+        error_append_hint(errp,
+                          "should be an address in hexa with 0x prefix\n");
+        goto out;
+    }
+
+    ret = qemu_strtou64(fields[1], NULL, 16, &addr);
+    if (!ret) {
+        interval->high = addr;
+    } else {
+        error_setg(errp, "Failed to decode interval high addr");
+        error_append_hint(errp,
+                          "should be an address in hexa with 0x prefix\n");
+        goto out;
+    }
+
+    ret = qemu_strtoui(fields[2], NULL, 10, &type);
+    if (!ret) {
+        interval->type = type;
+    } else {
+        error_setg(errp, "Failed to decode interval type");
+        error_append_hint(errp, "should be an unsigned int in decimal\n");
+    }
+out:
+    g_free(str);
+    g_strfreev(fields);
+    return;
+}
+
+const PropertyInfo qdev_prop_interval = {
+    .name  = "labelled_interval",
+    .description = "Labelled interval, example: 0xFEE00000,0xFEEFFFFF,0",
+    .get   = get_interval,
+    .set   = set_interval,
+};
+
 /* --- on/off/auto --- */
 
 const PropertyInfo qdev_prop_on_off_auto = {
diff --git a/include/exec/memory.h b/include/exec/memory.h
index e499dc215b..e238d1c352 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -57,6 +57,12 @@  struct MemoryRegionMmio {
     CPUWriteMemoryFunc *write[3];
 };
 
+struct Interval {
+    hwaddr low;
+    hwaddr high;
+    unsigned int type;
+};
+
 typedef struct IOMMUTLBEntry IOMMUTLBEntry;
 
 /* See address_space_translate: bit 0 is read, bit 1 is write.  */
diff --git a/include/hw/qdev-properties.h b/include/hw/qdev-properties.h
index c6a8cb5516..2ba7c8711b 100644
--- a/include/hw/qdev-properties.h
+++ b/include/hw/qdev-properties.h
@@ -20,6 +20,7 @@  extern const PropertyInfo qdev_prop_chr;
 extern const PropertyInfo qdev_prop_tpm;
 extern const PropertyInfo qdev_prop_ptr;
 extern const PropertyInfo qdev_prop_macaddr;
+extern const PropertyInfo qdev_prop_interval;
 extern const PropertyInfo qdev_prop_on_off_auto;
 extern const PropertyInfo qdev_prop_losttickpolicy;
 extern const PropertyInfo qdev_prop_blockdev_on_error;
@@ -202,6 +203,8 @@  extern const PropertyInfo qdev_prop_pcie_link_width;
     DEFINE_PROP(_n, _s, _f, qdev_prop_drive_iothread, BlockBackend *)
 #define DEFINE_PROP_MACADDR(_n, _s, _f)         \
     DEFINE_PROP(_n, _s, _f, qdev_prop_macaddr, MACAddr)
+#define DEFINE_PROP_INTERVAL(_n, _s, _f)         \
+    DEFINE_PROP(_n, _s, _f, qdev_prop_interval, Interval)
 #define DEFINE_PROP_ON_OFF_AUTO(_n, _s, _f, _d) \
     DEFINE_PROP_SIGNED(_n, _s, _f, _d, qdev_prop_on_off_auto, OnOffAuto)
 #define DEFINE_PROP_LOSTTICKPOLICY(_n, _s, _f, _d) \
diff --git a/include/qemu/typedefs.h b/include/qemu/typedefs.h
index 375770a80f..a827c9a3fe 100644
--- a/include/qemu/typedefs.h
+++ b/include/qemu/typedefs.h
@@ -58,6 +58,7 @@  typedef struct ISABus ISABus;
 typedef struct ISADevice ISADevice;
 typedef struct IsaDma IsaDma;
 typedef struct MACAddr MACAddr;
+typedef struct Interval Interval;
 typedef struct MachineClass MachineClass;
 typedef struct MachineState MachineState;
 typedef struct MemoryListener MemoryListener;