[v4,kvmtool,02/12] pci: Add helpers for BAR values and memory/IO space access

Commit Message

Alexandru Elisei May 14, 2020, 3:38 p.m. UTC

We're going to be checking the BAR type, the address written to it and if
access to memory or I/O space is enabled quite often when we add support
for reasignable BARs; make our life easier by adding helpers for it.

Reviewed-by: Andre Przywara <[e-mail]>
Signed-off-by: Alexandru Elisei <[e-mail]>
---
 include/kvm/pci.h   | 53 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 pci.c               |  4 ++--
 powerpc/spapr_pci.c |  2 +-
 3 files changed, 56 insertions(+), 3 deletions(-)

Patch

diff --git a/include/kvm/pci.h b/include/kvm/pci.h
index 2c29c094d4cb..0f0815b36157 100644
--- a/include/kvm/pci.h
+++ b/include/kvm/pci.h
@@ -5,6 +5,7 @@ 
 #include <linux/kvm.h>
 #include <linux/pci_regs.h>
 #include <endian.h>
+#include <stdbool.h>
 
 #include "kvm/devices.h"
 #include "kvm/msi.h"
@@ -161,4 +162,56 @@  void pci__config_rd(struct kvm *kvm, union pci_config_address addr, void *data,
 
 void *pci_find_cap(struct pci_device_header *hdr, u8 cap_type);
 
+static inline bool __pci__memory_space_enabled(u16 command)
+{
+	return command & PCI_COMMAND_MEMORY;
+}
+
+static inline bool pci__memory_space_enabled(struct pci_device_header *pci_hdr)
+{
+	return __pci__memory_space_enabled(pci_hdr->command);
+}
+
+static inline bool __pci__io_space_enabled(u16 command)
+{
+	return command & PCI_COMMAND_IO;
+}
+
+static inline bool pci__io_space_enabled(struct pci_device_header *pci_hdr)
+{
+	return __pci__io_space_enabled(pci_hdr->command);
+}
+
+static inline bool __pci__bar_is_io(u32 bar)
+{
+	return bar & PCI_BASE_ADDRESS_SPACE_IO;
+}
+
+static inline bool pci__bar_is_io(struct pci_device_header *pci_hdr, int bar_num)
+{
+	return __pci__bar_is_io(pci_hdr->bar[bar_num]);
+}
+
+static inline bool pci__bar_is_memory(struct pci_device_header *pci_hdr, int bar_num)
+{
+	return !pci__bar_is_io(pci_hdr, bar_num);
+}
+
+static inline u32 __pci__bar_address(u32 bar)
+{
+	if (__pci__bar_is_io(bar))
+		return bar & PCI_BASE_ADDRESS_IO_MASK;
+	return bar & PCI_BASE_ADDRESS_MEM_MASK;
+}
+
+static inline u32 pci__bar_address(struct pci_device_header *pci_hdr, int bar_num)
+{
+	return __pci__bar_address(pci_hdr->bar[bar_num]);
+}
+
+static inline u32 pci__bar_size(struct pci_device_header *pci_hdr, int bar_num)
+{
+	return pci_hdr->bar_size[bar_num];
+}
+
 #endif /* KVM__PCI_H */
diff --git a/pci.c b/pci.c
index 3ecdd0f9c75c..81e9cec918fb 100644
--- a/pci.c
+++ b/pci.c
@@ -185,7 +185,7 @@  void pci__config_wr(struct kvm *kvm, union pci_config_address addr, void *data,
 	 * size, it will write the address back.
 	 */
 	if (bar < 6) {
-		if (pci_hdr->bar[bar] & PCI_BASE_ADDRESS_SPACE_IO)
+		if (pci__bar_is_io(pci_hdr, bar))
 			mask = (u32)PCI_BASE_ADDRESS_IO_MASK;
 		else
 			mask = (u32)PCI_BASE_ADDRESS_MEM_MASK;
@@ -211,7 +211,7 @@  void pci__config_wr(struct kvm *kvm, union pci_config_address addr, void *data,
 		 */
 		memcpy(&value, data, size);
 		if (value == 0xffffffff)
-			value = ~(pci_hdr->bar_size[bar] - 1);
+			value = ~(pci__bar_size(pci_hdr, bar) - 1);
 		/* Preserve the special bits. */
 		value = (value & mask) | (pci_hdr->bar[bar] & ~mask);
 		memcpy(base + offset, &value, size);
diff --git a/powerpc/spapr_pci.c b/powerpc/spapr_pci.c
index a15f7d895a46..7be44d950acb 100644
--- a/powerpc/spapr_pci.c
+++ b/powerpc/spapr_pci.c
@@ -369,7 +369,7 @@  int spapr_populate_pci_devices(struct kvm *kvm,
 				of_pci_b_ddddd(devid) |
 				of_pci_b_fff(fn) |
 				of_pci_b_rrrrrrrr(bars[i]));
-			reg[n+1].size = cpu_to_be64(hdr->bar_size[i]);
+			reg[n+1].size = cpu_to_be64(pci__bar_size(hdr, i));
 			reg[n+1].addr = 0;
 
 			assigned_addresses[n].phys_hi = cpu_to_be32(