Re: [Qemu-devel] [PATCH v2 4/6] msix: Split PBA into it's own MemoryRegion

[Michael S. Tsirkin]

On Wed, Jun 13, 2012 at 10:51:47PM -0600, Alex Williamson wrote:
> These don't have to be contiguous.  Size them to only what
> they need and use separate MemoryRegions for the vector
> table and PBA.
> 
> Signed-off-by: Alex Williamson <address@hidden>

Why is this still using NATIVE?

> ---
> 
>  hw/msix.c |  116 
> ++++++++++++++++++++++++++++++++++++++-----------------------
>  hw/pci.h  |   15 ++++++--
>  2 files changed, 83 insertions(+), 48 deletions(-)
> 
> diff --git a/hw/msix.c b/hw/msix.c
> index a4cdfb0..d476d07 100644
> --- a/hw/msix.c
> +++ b/hw/msix.c
> @@ -37,7 +37,7 @@
>  
>  static MSIMessage msix_get_message(PCIDevice *dev, unsigned vector)
>  {
> -    uint8_t *table_entry = dev->msix_table_page + vector * 
> PCI_MSIX_ENTRY_SIZE;
> +    uint8_t *table_entry = dev->msix_table + vector * PCI_MSIX_ENTRY_SIZE;
>      MSIMessage msg;
>  
>      msg.address = pci_get_quad(table_entry + PCI_MSIX_ENTRY_LOWER_ADDR);
> @@ -86,16 +86,6 @@ static int msix_add_config(struct PCIDevice *pdev, 
> unsigned short nentries,
>      return 0;
>  }
>  
> -static uint64_t msix_mmio_read(void *opaque, target_phys_addr_t addr,
> -                               unsigned size)
> -{
> -    PCIDevice *dev = opaque;
> -    unsigned int offset = addr & (MSIX_PAGE_SIZE - 1) & ~0x3;
> -    void *page = dev->msix_table_page;
> -
> -    return pci_get_long(page + offset);
> -}
> -
>  static uint8_t msix_pending_mask(int vector)
>  {
>      return 1 << (vector % 8);
> @@ -103,7 +93,7 @@ static uint8_t msix_pending_mask(int vector)
>  
>  static uint8_t *msix_pending_byte(PCIDevice *dev, int vector)
>  {
> -    return dev->msix_table_page + MSIX_PAGE_PENDING + vector / 8;
> +    return dev->msix_pba + vector / 8;
>  }
>  
>  static int msix_is_pending(PCIDevice *dev, int vector)
> @@ -124,7 +114,7 @@ static void msix_clr_pending(PCIDevice *dev, int vector)
>  static bool msix_vector_masked(PCIDevice *dev, int vector, bool fmask)
>  {
>      unsigned offset = vector * PCI_MSIX_ENTRY_SIZE + 
> PCI_MSIX_ENTRY_VECTOR_CTRL;
> -    return fmask || dev->msix_table_page[offset] & 
> PCI_MSIX_ENTRY_CTRL_MASKBIT;
> +    return fmask || dev->msix_table[offset] & PCI_MSIX_ENTRY_CTRL_MASKBIT;
>  }
>  
>  static bool msix_is_masked(PCIDevice *dev, int vector)
> @@ -203,27 +193,46 @@ void msix_write_config(PCIDevice *dev, uint32_t addr,
>      }
>  }
>  
> -static void msix_mmio_write(void *opaque, target_phys_addr_t addr,
> -                            uint64_t val, unsigned size)
> +static uint64_t msix_table_mmio_read(void *opaque, target_phys_addr_t addr,
> +                                     unsigned size)
>  {
>      PCIDevice *dev = opaque;
> -    unsigned int offset = addr & (MSIX_PAGE_SIZE - 1) & ~0x3;
> -    int vector = offset / PCI_MSIX_ENTRY_SIZE;
> -    bool was_masked;
>  
> -    /* MSI-X page includes a read-only PBA and a writeable Vector Control. */
> -    if (vector >= dev->msix_entries_nr) {
> -        return;
> -    }
> +    return pci_get_long(dev->msix_table + addr);
> +}
> +
> +static void msix_table_mmio_write(void *opaque, target_phys_addr_t addr,
> +                                  uint64_t val, unsigned size)
> +{
> +    PCIDevice *dev = opaque;
> +    int vector = addr / PCI_MSIX_ENTRY_SIZE;
> +    bool was_masked;
>  
>      was_masked = msix_is_masked(dev, vector);
> -    pci_set_long(dev->msix_table_page + offset, val);
> +    pci_set_long(dev->msix_table + addr, val);
>      msix_handle_mask_update(dev, vector, was_masked);
>  }
>  
> -static const MemoryRegionOps msix_mmio_ops = {
> -    .read = msix_mmio_read,
> -    .write = msix_mmio_write,
> +static const MemoryRegionOps msix_table_mmio_ops = {
> +    .read = msix_table_mmio_read,
> +    .write = msix_table_mmio_write,
> +    .endianness = DEVICE_NATIVE_ENDIAN,
> +    .valid = {
> +        .min_access_size = 4,
> +        .max_access_size = 4,
> +    },
> +};
> +
> +static uint64_t msix_pba_mmio_read(void *opaque, target_phys_addr_t addr,
> +                                   unsigned size)
> +{
> +    PCIDevice *dev = opaque;
> +
> +    return pci_get_long(dev->msix_pba + addr);
> +}
> +
> +static const MemoryRegionOps msix_pba_mmio_ops = {
> +    .read = msix_pba_mmio_read,
>      .endianness = DEVICE_NATIVE_ENDIAN,
>      .valid = {
>          .min_access_size = 4,
> @@ -235,11 +244,14 @@ static void msix_mmio_setup(PCIDevice *d, MemoryRegion 
> *bar)
>  {
>      uint8_t *config = d->config + d->msix_cap;
>      uint32_t table = pci_get_long(config + PCI_MSIX_TABLE);
> -    uint32_t offset = table & ~(MSIX_PAGE_SIZE - 1);
> +    uint32_t table_offset = table & ~PCI_MSIX_FLAGS_BIRMASK;
> +    uint32_t pba = pci_get_long(config + PCI_MSIX_PBA);
> +    uint32_t pba_offset = pba & ~PCI_MSIX_FLAGS_BIRMASK;
>      /* TODO: for assigned devices, we'll want to make it possible to map
>       * pending bits separately in case they are in a separate bar. */
>  
> -    memory_region_add_subregion(bar, offset, &d->msix_mmio);
> +    memory_region_add_subregion(bar, table_offset, &d->msix_table_mmio);
> +    memory_region_add_subregion(bar, pba_offset, &d->msix_pba_mmio);
>  }
>  
>  static void msix_mask_all(struct PCIDevice *dev, unsigned nentries)
> @@ -251,7 +263,7 @@ static void msix_mask_all(struct PCIDevice *dev, unsigned 
> nentries)
>              vector * PCI_MSIX_ENTRY_SIZE + PCI_MSIX_ENTRY_VECTOR_CTRL;
>          bool was_masked = msix_is_masked(dev, vector);
>  
> -        dev->msix_table_page[offset] |= PCI_MSIX_ENTRY_CTRL_MASKBIT;
> +        dev->msix_table[offset] |= PCI_MSIX_ENTRY_CTRL_MASKBIT;
>          msix_handle_mask_update(dev, vector, was_masked);
>      }
>  }
> @@ -263,6 +275,7 @@ int msix_init(struct PCIDevice *dev, unsigned short 
> nentries,
>                unsigned bar_nr, unsigned bar_size)
>  {
>      int ret;
> +    unsigned table_size, pba_size;
>  
>      /* Nothing to do if MSI is not supported by interrupt controller */
>      if (!msi_supported) {
> @@ -271,14 +284,20 @@ int msix_init(struct PCIDevice *dev, unsigned short 
> nentries,
>      if (nentries > MSIX_MAX_ENTRIES)
>          return -EINVAL;
>  
> +    table_size = nentries * PCI_MSIX_ENTRY_SIZE;
> +    pba_size = QEMU_ALIGN_UP(nentries, 64) / 8;
> +
>      dev->msix_entry_used = g_malloc0(MSIX_MAX_ENTRIES *
>                                          sizeof *dev->msix_entry_used);
>  
> -    dev->msix_table_page = g_malloc0(MSIX_PAGE_SIZE);
> +    dev->msix_table = g_malloc0(table_size);
> +    dev->msix_pba = g_malloc0(pba_size);
>      msix_mask_all(dev, nentries);
>  
> -    memory_region_init_io(&dev->msix_mmio, &msix_mmio_ops, dev,
> -                          "msix", MSIX_PAGE_SIZE);
> +    memory_region_init_io(&dev->msix_table_mmio, &msix_table_mmio_ops, dev,
> +                          "msix", table_size);
> +    memory_region_init_io(&dev->msix_pba_mmio, &msix_pba_mmio_ops, dev,
> +                          "msix-pba", pba_size);
>  
>      dev->msix_entries_nr = nentries;
>      ret = msix_add_config(dev, nentries, bar_nr, bar_size);
> @@ -291,9 +310,12 @@ int msix_init(struct PCIDevice *dev, unsigned short 
> nentries,
>  
>  err_config:
>      dev->msix_entries_nr = 0;
> -    memory_region_destroy(&dev->msix_mmio);
> -    g_free(dev->msix_table_page);
> -    dev->msix_table_page = NULL;
> +    memory_region_destroy(&dev->msix_pba_mmio);
> +    g_free(dev->msix_pba);
> +    dev->msix_pba = NULL;
> +    memory_region_destroy(&dev->msix_table_mmio);
> +    g_free(dev->msix_table);
> +    dev->msix_table = NULL;
>      g_free(dev->msix_entry_used);
>      dev->msix_entry_used = NULL;
>      return ret;
> @@ -354,10 +376,14 @@ int msix_uninit(PCIDevice *dev, MemoryRegion *bar)
>      dev->msix_cap = 0;
>      msix_free_irq_entries(dev);
>      dev->msix_entries_nr = 0;
> -    memory_region_del_subregion(bar, &dev->msix_mmio);
> -    memory_region_destroy(&dev->msix_mmio);
> -    g_free(dev->msix_table_page);
> -    dev->msix_table_page = NULL;
> +    memory_region_del_subregion(bar, &dev->msix_pba_mmio);
> +    memory_region_destroy(&dev->msix_pba_mmio);
> +    g_free(dev->msix_pba);
> +    dev->msix_pba = NULL;
> +    memory_region_del_subregion(bar, &dev->msix_table_mmio);
> +    memory_region_destroy(&dev->msix_table_mmio);
> +    g_free(dev->msix_table);
> +    dev->msix_table = NULL;
>      g_free(dev->msix_entry_used);
>      dev->msix_entry_used = NULL;
>      dev->cap_present &= ~QEMU_PCI_CAP_MSIX;
> @@ -380,8 +406,8 @@ void msix_save(PCIDevice *dev, QEMUFile *f)
>          return;
>      }
>  
> -    qemu_put_buffer(f, dev->msix_table_page, n * PCI_MSIX_ENTRY_SIZE);
> -    qemu_put_buffer(f, dev->msix_table_page + MSIX_PAGE_PENDING, (n + 7) / 
> 8);
> +    qemu_put_buffer(f, dev->msix_table, n * PCI_MSIX_ENTRY_SIZE);
> +    qemu_put_buffer(f, dev->msix_pba, (n + 7) / 8);
>  }
>  
>  /* Should be called after restoring the config space. */
> @@ -395,8 +421,8 @@ void msix_load(PCIDevice *dev, QEMUFile *f)
>      }
>  
>      msix_free_irq_entries(dev);
> -    qemu_get_buffer(f, dev->msix_table_page, n * PCI_MSIX_ENTRY_SIZE);
> -    qemu_get_buffer(f, dev->msix_table_page + MSIX_PAGE_PENDING, (n + 7) / 
> 8);
> +    qemu_get_buffer(f, dev->msix_table, n * PCI_MSIX_ENTRY_SIZE);
> +    qemu_get_buffer(f, dev->msix_pba, (n + 7) / 8);
>      msix_update_function_masked(dev);
>  
>      for (vector = 0; vector < n; vector++) {
> @@ -443,7 +469,9 @@ void msix_reset(PCIDevice *dev)
>      msix_free_irq_entries(dev);
>      dev->config[dev->msix_cap + MSIX_CONTROL_OFFSET] &=
>           ~dev->wmask[dev->msix_cap + MSIX_CONTROL_OFFSET];
> -    memset(dev->msix_table_page, 0, MSIX_PAGE_SIZE);
> +
> +    memset(dev->msix_table, 0, dev->msix_entries_nr * PCI_MSIX_ENTRY_SIZE);
> +    memset(dev->msix_pba, 0, QEMU_ALIGN_UP(dev->msix_entries_nr, 64) / 8);
>      msix_mask_all(dev, dev->msix_entries_nr);
>  }
>  
> diff --git a/hw/pci.h b/hw/pci.h
> index d517a54..bd64445 100644
> --- a/hw/pci.h
> +++ b/hw/pci.h
> @@ -224,16 +224,23 @@ struct PCIDevice {
>      /* MSI-X entries */
>      int msix_entries_nr;
>  
> -    /* Space to store MSIX table */
> -    uint8_t *msix_table_page;
> +    /* Space to store MSIX table & pending bit array */
> +    uint8_t *msix_table;
> +    uint8_t *msix_pba;
> +
>      /* MemoryRegion container for msix exclusive BAR setup */
>      MemoryRegion msix_exclusive_bar;
> -    /* MMIO index used to map MSIX table and pending bit entries. */
> -    MemoryRegion msix_mmio;
> +
> +    /* Memory Regions for MSIX table and pending bit entries. */
> +    MemoryRegion msix_table_mmio;
> +    MemoryRegion msix_pba_mmio;
> +
>      /* Reference-count for entries actually in use by driver. */
>      unsigned *msix_entry_used;
> +
>      /* MSIX function mask set or MSIX disabled */
>      bool msix_function_masked;
> +
>      /* Version id needed for VMState */
>      int32_t version_id;
>