1 // SPDX-License-Identifier: GPL-2.0-only
3 * VFIO PCI config space virtualization
5 * Copyright (C) 2012 Red Hat, Inc. All rights reserved.
6 * Author: Alex Williamson <alex.williamson@redhat.com>
8 * Derived from original vfio:
9 * Copyright 2010 Cisco Systems, Inc. All rights reserved.
10 * Author: Tom Lyon, pugs@cisco.com
14 * This code handles reading and writing of PCI configuration registers.
15 * This is hairy because we want to allow a lot of flexibility to the
16 * user driver, but cannot trust it with all of the config fields.
17 * Tables determine which fields can be read and written, as well as
18 * which fields are 'virtualized' - special actions and translations to
19 * make it appear to the user that he has control, when in fact things
20 * must be negotiated with the underlying OS.
24 #include <linux/pci.h>
25 #include <linux/uaccess.h>
26 #include <linux/vfio.h>
27 #include <linux/slab.h>
29 #include "vfio_pci_private.h"
31 /* Fake capability ID for standard config space */
32 #define PCI_CAP_ID_BASIC 0
34 #define is_bar(offset) \
35 ((offset >= PCI_BASE_ADDRESS_0 && offset < PCI_BASE_ADDRESS_5 + 4) || \
36 (offset >= PCI_ROM_ADDRESS && offset < PCI_ROM_ADDRESS + 4))
39 * Lengths of PCI Config Capabilities
40 * 0: Removed from the user visible capability list
43 static const u8 pci_cap_length
[PCI_CAP_ID_MAX
+ 1] = {
44 [PCI_CAP_ID_BASIC
] = PCI_STD_HEADER_SIZEOF
, /* pci config header */
45 [PCI_CAP_ID_PM
] = PCI_PM_SIZEOF
,
46 [PCI_CAP_ID_AGP
] = PCI_AGP_SIZEOF
,
47 [PCI_CAP_ID_VPD
] = PCI_CAP_VPD_SIZEOF
,
48 [PCI_CAP_ID_SLOTID
] = 0, /* bridge - don't care */
49 [PCI_CAP_ID_MSI
] = 0xFF, /* 10, 14, 20, or 24 */
50 [PCI_CAP_ID_CHSWP
] = 0, /* cpci - not yet */
51 [PCI_CAP_ID_PCIX
] = 0xFF, /* 8 or 24 */
52 [PCI_CAP_ID_HT
] = 0xFF, /* hypertransport */
53 [PCI_CAP_ID_VNDR
] = 0xFF, /* variable */
54 [PCI_CAP_ID_DBG
] = 0, /* debug - don't care */
55 [PCI_CAP_ID_CCRC
] = 0, /* cpci - not yet */
56 [PCI_CAP_ID_SHPC
] = 0, /* hotswap - not yet */
57 [PCI_CAP_ID_SSVID
] = 0, /* bridge - don't care */
58 [PCI_CAP_ID_AGP3
] = 0, /* AGP8x - not yet */
59 [PCI_CAP_ID_SECDEV
] = 0, /* secure device not yet */
60 [PCI_CAP_ID_EXP
] = 0xFF, /* 20 or 44 */
61 [PCI_CAP_ID_MSIX
] = PCI_CAP_MSIX_SIZEOF
,
62 [PCI_CAP_ID_SATA
] = 0xFF,
63 [PCI_CAP_ID_AF
] = PCI_CAP_AF_SIZEOF
,
67 * Lengths of PCIe/PCI-X Extended Config Capabilities
68 * 0: Removed or masked from the user visible capability list
71 static const u16 pci_ext_cap_length
[PCI_EXT_CAP_ID_MAX
+ 1] = {
72 [PCI_EXT_CAP_ID_ERR
] = PCI_ERR_ROOT_COMMAND
,
73 [PCI_EXT_CAP_ID_VC
] = 0xFF,
74 [PCI_EXT_CAP_ID_DSN
] = PCI_EXT_CAP_DSN_SIZEOF
,
75 [PCI_EXT_CAP_ID_PWR
] = PCI_EXT_CAP_PWR_SIZEOF
,
76 [PCI_EXT_CAP_ID_RCLD
] = 0, /* root only - don't care */
77 [PCI_EXT_CAP_ID_RCILC
] = 0, /* root only - don't care */
78 [PCI_EXT_CAP_ID_RCEC
] = 0, /* root only - don't care */
79 [PCI_EXT_CAP_ID_MFVC
] = 0xFF,
80 [PCI_EXT_CAP_ID_VC9
] = 0xFF, /* same as CAP_ID_VC */
81 [PCI_EXT_CAP_ID_RCRB
] = 0, /* root only - don't care */
82 [PCI_EXT_CAP_ID_VNDR
] = 0xFF,
83 [PCI_EXT_CAP_ID_CAC
] = 0, /* obsolete */
84 [PCI_EXT_CAP_ID_ACS
] = 0xFF,
85 [PCI_EXT_CAP_ID_ARI
] = PCI_EXT_CAP_ARI_SIZEOF
,
86 [PCI_EXT_CAP_ID_ATS
] = PCI_EXT_CAP_ATS_SIZEOF
,
87 [PCI_EXT_CAP_ID_SRIOV
] = PCI_EXT_CAP_SRIOV_SIZEOF
,
88 [PCI_EXT_CAP_ID_MRIOV
] = 0, /* not yet */
89 [PCI_EXT_CAP_ID_MCAST
] = PCI_EXT_CAP_MCAST_ENDPOINT_SIZEOF
,
90 [PCI_EXT_CAP_ID_PRI
] = PCI_EXT_CAP_PRI_SIZEOF
,
91 [PCI_EXT_CAP_ID_AMD_XXX
] = 0, /* not yet */
92 [PCI_EXT_CAP_ID_REBAR
] = 0xFF,
93 [PCI_EXT_CAP_ID_DPA
] = 0xFF,
94 [PCI_EXT_CAP_ID_TPH
] = 0xFF,
95 [PCI_EXT_CAP_ID_LTR
] = PCI_EXT_CAP_LTR_SIZEOF
,
96 [PCI_EXT_CAP_ID_SECPCI
] = 0, /* not yet */
97 [PCI_EXT_CAP_ID_PMUX
] = 0, /* not yet */
98 [PCI_EXT_CAP_ID_PASID
] = 0, /* not yet */
102 * Read/Write Permission Bits - one bit for each bit in capability
103 * Any field can be read if it exists, but what is read depends on
104 * whether the field is 'virtualized', or just pass thru to the
105 * hardware. Any virtualized field is also virtualized for writes.
106 * Writes are only permitted if they have a 1 bit here.
109 u8
*virt
; /* read/write virtual data, not hw */
110 u8
*write
; /* writeable bits */
111 int (*readfn
)(struct vfio_pci_device
*vdev
, int pos
, int count
,
112 struct perm_bits
*perm
, int offset
, __le32
*val
);
113 int (*writefn
)(struct vfio_pci_device
*vdev
, int pos
, int count
,
114 struct perm_bits
*perm
, int offset
, __le32 val
);
118 #define ALL_VIRT 0xFFFFFFFFU
120 #define ALL_WRITE 0xFFFFFFFFU
122 static int vfio_user_config_read(struct pci_dev
*pdev
, int offset
,
123 __le32
*val
, int count
)
132 ret
= pci_user_read_config_byte(pdev
, offset
, &tmp
);
139 ret
= pci_user_read_config_word(pdev
, offset
, &tmp
);
144 ret
= pci_user_read_config_dword(pdev
, offset
, &tmp_val
);
148 *val
= cpu_to_le32(tmp_val
);
153 static int vfio_user_config_write(struct pci_dev
*pdev
, int offset
,
154 __le32 val
, int count
)
157 u32 tmp_val
= le32_to_cpu(val
);
161 ret
= pci_user_write_config_byte(pdev
, offset
, tmp_val
);
164 ret
= pci_user_write_config_word(pdev
, offset
, tmp_val
);
167 ret
= pci_user_write_config_dword(pdev
, offset
, tmp_val
);
174 static int vfio_default_config_read(struct vfio_pci_device
*vdev
, int pos
,
175 int count
, struct perm_bits
*perm
,
176 int offset
, __le32
*val
)
180 memcpy(val
, vdev
->vconfig
+ pos
, count
);
182 memcpy(&virt
, perm
->virt
+ offset
, count
);
184 /* Any non-virtualized bits? */
185 if (cpu_to_le32(~0U >> (32 - (count
* 8))) != virt
) {
186 struct pci_dev
*pdev
= vdev
->pdev
;
190 ret
= vfio_user_config_read(pdev
, pos
, &phys_val
, count
);
194 *val
= (phys_val
& ~virt
) | (*val
& virt
);
200 static int vfio_default_config_write(struct vfio_pci_device
*vdev
, int pos
,
201 int count
, struct perm_bits
*perm
,
202 int offset
, __le32 val
)
204 __le32 virt
= 0, write
= 0;
206 memcpy(&write
, perm
->write
+ offset
, count
);
209 return count
; /* drop, no writable bits */
211 memcpy(&virt
, perm
->virt
+ offset
, count
);
213 /* Virtualized and writable bits go to vconfig */
217 memcpy(&virt_val
, vdev
->vconfig
+ pos
, count
);
219 virt_val
&= ~(write
& virt
);
220 virt_val
|= (val
& (write
& virt
));
222 memcpy(vdev
->vconfig
+ pos
, &virt_val
, count
);
225 /* Non-virtualzed and writable bits go to hardware */
227 struct pci_dev
*pdev
= vdev
->pdev
;
231 ret
= vfio_user_config_read(pdev
, pos
, &phys_val
, count
);
235 phys_val
&= ~(write
& ~virt
);
236 phys_val
|= (val
& (write
& ~virt
));
238 ret
= vfio_user_config_write(pdev
, pos
, phys_val
, count
);
246 /* Allow direct read from hardware, except for capability next pointer */
247 static int vfio_direct_config_read(struct vfio_pci_device
*vdev
, int pos
,
248 int count
, struct perm_bits
*perm
,
249 int offset
, __le32
*val
)
253 ret
= vfio_user_config_read(vdev
->pdev
, pos
, val
, count
);
257 if (pos
>= PCI_CFG_SPACE_SIZE
) { /* Extended cap header mangling */
259 memcpy(val
, vdev
->vconfig
+ pos
, count
);
260 } else if (pos
>= PCI_STD_HEADER_SIZEOF
) { /* Std cap mangling */
261 if (offset
== PCI_CAP_LIST_ID
&& count
> 1)
262 memcpy(val
, vdev
->vconfig
+ pos
,
263 min(PCI_CAP_FLAGS
, count
));
264 else if (offset
== PCI_CAP_LIST_NEXT
)
265 memcpy(val
, vdev
->vconfig
+ pos
, 1);
271 /* Raw access skips any kind of virtualization */
272 static int vfio_raw_config_write(struct vfio_pci_device
*vdev
, int pos
,
273 int count
, struct perm_bits
*perm
,
274 int offset
, __le32 val
)
278 ret
= vfio_user_config_write(vdev
->pdev
, pos
, val
, count
);
285 static int vfio_raw_config_read(struct vfio_pci_device
*vdev
, int pos
,
286 int count
, struct perm_bits
*perm
,
287 int offset
, __le32
*val
)
291 ret
= vfio_user_config_read(vdev
->pdev
, pos
, val
, count
);
298 /* Virt access uses only virtualization */
299 static int vfio_virt_config_write(struct vfio_pci_device
*vdev
, int pos
,
300 int count
, struct perm_bits
*perm
,
301 int offset
, __le32 val
)
303 memcpy(vdev
->vconfig
+ pos
, &val
, count
);
307 static int vfio_virt_config_read(struct vfio_pci_device
*vdev
, int pos
,
308 int count
, struct perm_bits
*perm
,
309 int offset
, __le32
*val
)
311 memcpy(val
, vdev
->vconfig
+ pos
, count
);
315 /* Default capability regions to read-only, no-virtualization */
316 static struct perm_bits cap_perms
[PCI_CAP_ID_MAX
+ 1] = {
317 [0 ... PCI_CAP_ID_MAX
] = { .readfn
= vfio_direct_config_read
}
319 static struct perm_bits ecap_perms
[PCI_EXT_CAP_ID_MAX
+ 1] = {
320 [0 ... PCI_EXT_CAP_ID_MAX
] = { .readfn
= vfio_direct_config_read
}
323 * Default unassigned regions to raw read-write access. Some devices
324 * require this to function as they hide registers between the gaps in
325 * config space (be2net). Like MMIO and I/O port registers, we have
326 * to trust the hardware isolation.
328 static struct perm_bits unassigned_perms
= {
329 .readfn
= vfio_raw_config_read
,
330 .writefn
= vfio_raw_config_write
333 static struct perm_bits virt_perms
= {
334 .readfn
= vfio_virt_config_read
,
335 .writefn
= vfio_virt_config_write
338 static void free_perm_bits(struct perm_bits
*perm
)
346 static int alloc_perm_bits(struct perm_bits
*perm
, int size
)
349 * Round up all permission bits to the next dword, this lets us
350 * ignore whether a read/write exceeds the defined capability
351 * structure. We can do this because:
352 * - Standard config space is already dword aligned
353 * - Capabilities are all dword aligned (bits 0:1 of next reserved)
354 * - Express capabilities defined as dword aligned
356 size
= round_up(size
, 4);
360 * - All Readable, None Writeable, None Virtualized
362 perm
->virt
= kzalloc(size
, GFP_KERNEL
);
363 perm
->write
= kzalloc(size
, GFP_KERNEL
);
364 if (!perm
->virt
|| !perm
->write
) {
365 free_perm_bits(perm
);
369 perm
->readfn
= vfio_default_config_read
;
370 perm
->writefn
= vfio_default_config_write
;
376 * Helper functions for filling in permission tables
378 static inline void p_setb(struct perm_bits
*p
, int off
, u8 virt
, u8 write
)
381 p
->write
[off
] = write
;
384 /* Handle endian-ness - pci and tables are little-endian */
385 static inline void p_setw(struct perm_bits
*p
, int off
, u16 virt
, u16 write
)
387 *(__le16
*)(&p
->virt
[off
]) = cpu_to_le16(virt
);
388 *(__le16
*)(&p
->write
[off
]) = cpu_to_le16(write
);
391 /* Handle endian-ness - pci and tables are little-endian */
392 static inline void p_setd(struct perm_bits
*p
, int off
, u32 virt
, u32 write
)
394 *(__le32
*)(&p
->virt
[off
]) = cpu_to_le32(virt
);
395 *(__le32
*)(&p
->write
[off
]) = cpu_to_le32(write
);
398 /* Caller should hold memory_lock semaphore */
399 bool __vfio_pci_memory_enabled(struct vfio_pci_device
*vdev
)
401 struct pci_dev
*pdev
= vdev
->pdev
;
402 u16 cmd
= le16_to_cpu(*(__le16
*)&vdev
->vconfig
[PCI_COMMAND
]);
405 * SR-IOV VF memory enable is handled by the MSE bit in the
406 * PF SR-IOV capability, there's therefore no need to trigger
407 * faults based on the virtual value.
409 return pdev
->no_command_memory
|| (cmd
& PCI_COMMAND_MEMORY
);
413 * Restore the *real* BARs after we detect a FLR or backdoor reset.
414 * (backdoor = some device specific technique that we didn't catch)
416 static void vfio_bar_restore(struct vfio_pci_device
*vdev
)
418 struct pci_dev
*pdev
= vdev
->pdev
;
419 u32
*rbar
= vdev
->rbar
;
426 pci_info(pdev
, "%s: reset recovery - restoring BARs\n", __func__
);
428 for (i
= PCI_BASE_ADDRESS_0
; i
<= PCI_BASE_ADDRESS_5
; i
+= 4, rbar
++)
429 pci_user_write_config_dword(pdev
, i
, *rbar
);
431 pci_user_write_config_dword(pdev
, PCI_ROM_ADDRESS
, *rbar
);
434 pci_user_read_config_word(pdev
, PCI_COMMAND
, &cmd
);
435 cmd
|= PCI_COMMAND_INTX_DISABLE
;
436 pci_user_write_config_word(pdev
, PCI_COMMAND
, cmd
);
440 static __le32
vfio_generate_bar_flags(struct pci_dev
*pdev
, int bar
)
442 unsigned long flags
= pci_resource_flags(pdev
, bar
);
445 if (flags
& IORESOURCE_IO
)
446 return cpu_to_le32(PCI_BASE_ADDRESS_SPACE_IO
);
448 val
= PCI_BASE_ADDRESS_SPACE_MEMORY
;
450 if (flags
& IORESOURCE_PREFETCH
)
451 val
|= PCI_BASE_ADDRESS_MEM_PREFETCH
;
453 if (flags
& IORESOURCE_MEM_64
)
454 val
|= PCI_BASE_ADDRESS_MEM_TYPE_64
;
456 return cpu_to_le32(val
);
460 * Pretend we're hardware and tweak the values of the *virtual* PCI BARs
461 * to reflect the hardware capabilities. This implements BAR sizing.
463 static void vfio_bar_fixup(struct vfio_pci_device
*vdev
)
465 struct pci_dev
*pdev
= vdev
->pdev
;
473 vbar
= (__le32
*)&vdev
->vconfig
[PCI_BASE_ADDRESS_0
];
475 for (i
= 0; i
< PCI_STD_NUM_BARS
; i
++, vbar
++) {
476 int bar
= i
+ PCI_STD_RESOURCES
;
478 if (!pci_resource_start(pdev
, bar
)) {
479 *vbar
= 0; /* Unmapped by host = unimplemented to user */
483 mask
= ~(pci_resource_len(pdev
, bar
) - 1);
485 *vbar
&= cpu_to_le32((u32
)mask
);
486 *vbar
|= vfio_generate_bar_flags(pdev
, bar
);
488 if (*vbar
& cpu_to_le32(PCI_BASE_ADDRESS_MEM_TYPE_64
)) {
490 *vbar
&= cpu_to_le32((u32
)(mask
>> 32));
495 vbar
= (__le32
*)&vdev
->vconfig
[PCI_ROM_ADDRESS
];
498 * NB. REGION_INFO will have reported zero size if we weren't able
499 * to read the ROM, but we still return the actual BAR size here if
500 * it exists (or the shadow ROM space).
502 if (pci_resource_start(pdev
, PCI_ROM_RESOURCE
)) {
503 mask
= ~(pci_resource_len(pdev
, PCI_ROM_RESOURCE
) - 1);
504 mask
|= PCI_ROM_ADDRESS_ENABLE
;
505 *vbar
&= cpu_to_le32((u32
)mask
);
506 } else if (pdev
->resource
[PCI_ROM_RESOURCE
].flags
&
507 IORESOURCE_ROM_SHADOW
) {
508 mask
= ~(0x20000 - 1);
509 mask
|= PCI_ROM_ADDRESS_ENABLE
;
510 *vbar
&= cpu_to_le32((u32
)mask
);
514 vdev
->bardirty
= false;
517 static int vfio_basic_config_read(struct vfio_pci_device
*vdev
, int pos
,
518 int count
, struct perm_bits
*perm
,
519 int offset
, __le32
*val
)
521 if (is_bar(offset
)) /* pos == offset for basic config */
522 vfio_bar_fixup(vdev
);
524 count
= vfio_default_config_read(vdev
, pos
, count
, perm
, offset
, val
);
526 /* Mask in virtual memory enable */
527 if (offset
== PCI_COMMAND
&& vdev
->pdev
->no_command_memory
) {
528 u16 cmd
= le16_to_cpu(*(__le16
*)&vdev
->vconfig
[PCI_COMMAND
]);
529 u32 tmp_val
= le32_to_cpu(*val
);
531 tmp_val
|= cmd
& PCI_COMMAND_MEMORY
;
532 *val
= cpu_to_le32(tmp_val
);
538 /* Test whether BARs match the value we think they should contain */
539 static bool vfio_need_bar_restore(struct vfio_pci_device
*vdev
)
541 int i
= 0, pos
= PCI_BASE_ADDRESS_0
, ret
;
544 for (; pos
<= PCI_BASE_ADDRESS_5
; i
++, pos
+= 4) {
546 ret
= pci_user_read_config_dword(vdev
->pdev
, pos
, &bar
);
547 if (ret
|| vdev
->rbar
[i
] != bar
)
555 static int vfio_basic_config_write(struct vfio_pci_device
*vdev
, int pos
,
556 int count
, struct perm_bits
*perm
,
557 int offset
, __le32 val
)
559 struct pci_dev
*pdev
= vdev
->pdev
;
564 virt_cmd
= (__le16
*)&vdev
->vconfig
[PCI_COMMAND
];
566 if (offset
== PCI_COMMAND
) {
567 bool phys_mem
, virt_mem
, new_mem
, phys_io
, virt_io
, new_io
;
570 ret
= pci_user_read_config_word(pdev
, PCI_COMMAND
, &phys_cmd
);
574 new_cmd
= le32_to_cpu(val
);
576 phys_io
= !!(phys_cmd
& PCI_COMMAND_IO
);
577 virt_io
= !!(le16_to_cpu(*virt_cmd
) & PCI_COMMAND_IO
);
578 new_io
= !!(new_cmd
& PCI_COMMAND_IO
);
580 phys_mem
= !!(phys_cmd
& PCI_COMMAND_MEMORY
);
581 virt_mem
= !!(le16_to_cpu(*virt_cmd
) & PCI_COMMAND_MEMORY
);
582 new_mem
= !!(new_cmd
& PCI_COMMAND_MEMORY
);
585 vfio_pci_zap_and_down_write_memory_lock(vdev
);
587 down_write(&vdev
->memory_lock
);
590 * If the user is writing mem/io enable (new_mem/io) and we
591 * think it's already enabled (virt_mem/io), but the hardware
592 * shows it disabled (phys_mem/io, then the device has
593 * undergone some kind of backdoor reset and needs to be
594 * restored before we allow it to enable the bars.
595 * SR-IOV devices will trigger this - for mem enable let's
596 * catch this now and for io enable it will be caught later
598 if ((new_mem
&& virt_mem
&& !phys_mem
&&
599 !pdev
->no_command_memory
) ||
600 (new_io
&& virt_io
&& !phys_io
) ||
601 vfio_need_bar_restore(vdev
))
602 vfio_bar_restore(vdev
);
605 count
= vfio_default_config_write(vdev
, pos
, count
, perm
, offset
, val
);
607 if (offset
== PCI_COMMAND
)
608 up_write(&vdev
->memory_lock
);
613 * Save current memory/io enable bits in vconfig to allow for
614 * the test above next time.
616 if (offset
== PCI_COMMAND
) {
617 u16 mask
= PCI_COMMAND_MEMORY
| PCI_COMMAND_IO
;
619 *virt_cmd
&= cpu_to_le16(~mask
);
620 *virt_cmd
|= cpu_to_le16(new_cmd
& mask
);
622 up_write(&vdev
->memory_lock
);
625 /* Emulate INTx disable */
626 if (offset
>= PCI_COMMAND
&& offset
<= PCI_COMMAND
+ 1) {
627 bool virt_intx_disable
;
629 virt_intx_disable
= !!(le16_to_cpu(*virt_cmd
) &
630 PCI_COMMAND_INTX_DISABLE
);
632 if (virt_intx_disable
&& !vdev
->virq_disabled
) {
633 vdev
->virq_disabled
= true;
634 vfio_pci_intx_mask(vdev
);
635 } else if (!virt_intx_disable
&& vdev
->virq_disabled
) {
636 vdev
->virq_disabled
= false;
637 vfio_pci_intx_unmask(vdev
);
642 vdev
->bardirty
= true;
647 /* Permissions for the Basic PCI Header */
648 static int __init
init_pci_cap_basic_perm(struct perm_bits
*perm
)
650 if (alloc_perm_bits(perm
, PCI_STD_HEADER_SIZEOF
))
653 perm
->readfn
= vfio_basic_config_read
;
654 perm
->writefn
= vfio_basic_config_write
;
656 /* Virtualized for SR-IOV functions, which just have FFFF */
657 p_setw(perm
, PCI_VENDOR_ID
, (u16
)ALL_VIRT
, NO_WRITE
);
658 p_setw(perm
, PCI_DEVICE_ID
, (u16
)ALL_VIRT
, NO_WRITE
);
661 * Virtualize INTx disable, we use it internally for interrupt
662 * control and can emulate it for non-PCI 2.3 devices.
664 p_setw(perm
, PCI_COMMAND
, PCI_COMMAND_INTX_DISABLE
, (u16
)ALL_WRITE
);
666 /* Virtualize capability list, we might want to skip/disable */
667 p_setw(perm
, PCI_STATUS
, PCI_STATUS_CAP_LIST
, NO_WRITE
);
669 /* No harm to write */
670 p_setb(perm
, PCI_CACHE_LINE_SIZE
, NO_VIRT
, (u8
)ALL_WRITE
);
671 p_setb(perm
, PCI_LATENCY_TIMER
, NO_VIRT
, (u8
)ALL_WRITE
);
672 p_setb(perm
, PCI_BIST
, NO_VIRT
, (u8
)ALL_WRITE
);
674 /* Virtualize all bars, can't touch the real ones */
675 p_setd(perm
, PCI_BASE_ADDRESS_0
, ALL_VIRT
, ALL_WRITE
);
676 p_setd(perm
, PCI_BASE_ADDRESS_1
, ALL_VIRT
, ALL_WRITE
);
677 p_setd(perm
, PCI_BASE_ADDRESS_2
, ALL_VIRT
, ALL_WRITE
);
678 p_setd(perm
, PCI_BASE_ADDRESS_3
, ALL_VIRT
, ALL_WRITE
);
679 p_setd(perm
, PCI_BASE_ADDRESS_4
, ALL_VIRT
, ALL_WRITE
);
680 p_setd(perm
, PCI_BASE_ADDRESS_5
, ALL_VIRT
, ALL_WRITE
);
681 p_setd(perm
, PCI_ROM_ADDRESS
, ALL_VIRT
, ALL_WRITE
);
683 /* Allow us to adjust capability chain */
684 p_setb(perm
, PCI_CAPABILITY_LIST
, (u8
)ALL_VIRT
, NO_WRITE
);
686 /* Sometimes used by sw, just virtualize */
687 p_setb(perm
, PCI_INTERRUPT_LINE
, (u8
)ALL_VIRT
, (u8
)ALL_WRITE
);
689 /* Virtualize interrupt pin to allow hiding INTx */
690 p_setb(perm
, PCI_INTERRUPT_PIN
, (u8
)ALL_VIRT
, (u8
)NO_WRITE
);
695 static int vfio_pm_config_write(struct vfio_pci_device
*vdev
, int pos
,
696 int count
, struct perm_bits
*perm
,
697 int offset
, __le32 val
)
699 count
= vfio_default_config_write(vdev
, pos
, count
, perm
, offset
, val
);
703 if (offset
== PCI_PM_CTRL
) {
706 switch (le32_to_cpu(val
) & PCI_PM_CTRL_STATE_MASK
) {
721 vfio_pci_set_power_state(vdev
, state
);
727 /* Permissions for the Power Management capability */
728 static int __init
init_pci_cap_pm_perm(struct perm_bits
*perm
)
730 if (alloc_perm_bits(perm
, pci_cap_length
[PCI_CAP_ID_PM
]))
733 perm
->writefn
= vfio_pm_config_write
;
736 * We always virtualize the next field so we can remove
737 * capabilities from the chain if we want to.
739 p_setb(perm
, PCI_CAP_LIST_NEXT
, (u8
)ALL_VIRT
, NO_WRITE
);
742 * Power management is defined *per function*, so we can let
743 * the user change power state, but we trap and initiate the
744 * change ourselves, so the state bits are read-only.
746 p_setd(perm
, PCI_PM_CTRL
, NO_VIRT
, ~PCI_PM_CTRL_STATE_MASK
);
750 static int vfio_vpd_config_write(struct vfio_pci_device
*vdev
, int pos
,
751 int count
, struct perm_bits
*perm
,
752 int offset
, __le32 val
)
754 struct pci_dev
*pdev
= vdev
->pdev
;
755 __le16
*paddr
= (__le16
*)(vdev
->vconfig
+ pos
- offset
+ PCI_VPD_ADDR
);
756 __le32
*pdata
= (__le32
*)(vdev
->vconfig
+ pos
- offset
+ PCI_VPD_DATA
);
761 * Write through to emulation. If the write includes the upper byte
762 * of PCI_VPD_ADDR, then the PCI_VPD_ADDR_F bit is written and we
765 count
= vfio_default_config_write(vdev
, pos
, count
, perm
, offset
, val
);
766 if (count
< 0 || offset
> PCI_VPD_ADDR
+ 1 ||
767 offset
+ count
<= PCI_VPD_ADDR
+ 1)
770 addr
= le16_to_cpu(*paddr
);
772 if (addr
& PCI_VPD_ADDR_F
) {
773 data
= le32_to_cpu(*pdata
);
774 if (pci_write_vpd(pdev
, addr
& ~PCI_VPD_ADDR_F
, 4, &data
) != 4)
778 if (pci_read_vpd(pdev
, addr
, 4, &data
) < 0)
780 *pdata
= cpu_to_le32(data
);
784 * Toggle PCI_VPD_ADDR_F in the emulated PCI_VPD_ADDR register to
785 * signal completion. If an error occurs above, we assume that not
786 * toggling this bit will induce a driver timeout.
788 addr
^= PCI_VPD_ADDR_F
;
789 *paddr
= cpu_to_le16(addr
);
794 /* Permissions for Vital Product Data capability */
795 static int __init
init_pci_cap_vpd_perm(struct perm_bits
*perm
)
797 if (alloc_perm_bits(perm
, pci_cap_length
[PCI_CAP_ID_VPD
]))
800 perm
->writefn
= vfio_vpd_config_write
;
803 * We always virtualize the next field so we can remove
804 * capabilities from the chain if we want to.
806 p_setb(perm
, PCI_CAP_LIST_NEXT
, (u8
)ALL_VIRT
, NO_WRITE
);
809 * Both the address and data registers are virtualized to
810 * enable access through the pci_vpd_read/write functions
812 p_setw(perm
, PCI_VPD_ADDR
, (u16
)ALL_VIRT
, (u16
)ALL_WRITE
);
813 p_setd(perm
, PCI_VPD_DATA
, ALL_VIRT
, ALL_WRITE
);
818 /* Permissions for PCI-X capability */
819 static int __init
init_pci_cap_pcix_perm(struct perm_bits
*perm
)
821 /* Alloc 24, but only 8 are used in v0 */
822 if (alloc_perm_bits(perm
, PCI_CAP_PCIX_SIZEOF_V2
))
825 p_setb(perm
, PCI_CAP_LIST_NEXT
, (u8
)ALL_VIRT
, NO_WRITE
);
827 p_setw(perm
, PCI_X_CMD
, NO_VIRT
, (u16
)ALL_WRITE
);
828 p_setd(perm
, PCI_X_ECC_CSR
, NO_VIRT
, ALL_WRITE
);
832 static int vfio_exp_config_write(struct vfio_pci_device
*vdev
, int pos
,
833 int count
, struct perm_bits
*perm
,
834 int offset
, __le32 val
)
836 __le16
*ctrl
= (__le16
*)(vdev
->vconfig
+ pos
-
837 offset
+ PCI_EXP_DEVCTL
);
838 int readrq
= le16_to_cpu(*ctrl
) & PCI_EXP_DEVCTL_READRQ
;
840 count
= vfio_default_config_write(vdev
, pos
, count
, perm
, offset
, val
);
845 * The FLR bit is virtualized, if set and the device supports PCIe
846 * FLR, issue a reset_function. Regardless, clear the bit, the spec
847 * requires it to be always read as zero. NB, reset_function might
848 * not use a PCIe FLR, we don't have that level of granularity.
850 if (*ctrl
& cpu_to_le16(PCI_EXP_DEVCTL_BCR_FLR
)) {
854 *ctrl
&= ~cpu_to_le16(PCI_EXP_DEVCTL_BCR_FLR
);
856 ret
= pci_user_read_config_dword(vdev
->pdev
,
857 pos
- offset
+ PCI_EXP_DEVCAP
,
860 if (!ret
&& (cap
& PCI_EXP_DEVCAP_FLR
)) {
861 vfio_pci_zap_and_down_write_memory_lock(vdev
);
862 pci_try_reset_function(vdev
->pdev
);
863 up_write(&vdev
->memory_lock
);
868 * MPS is virtualized to the user, writes do not change the physical
869 * register since determining a proper MPS value requires a system wide
870 * device view. The MRRS is largely independent of MPS, but since the
871 * user does not have that system-wide view, they might set a safe, but
872 * inefficiently low value. Here we allow writes through to hardware,
873 * but we set the floor to the physical device MPS setting, so that
874 * we can at least use full TLPs, as defined by the MPS value.
876 * NB, if any devices actually depend on an artificially low MRRS
877 * setting, this will need to be revisited, perhaps with a quirk
878 * though pcie_set_readrq().
880 if (readrq
!= (le16_to_cpu(*ctrl
) & PCI_EXP_DEVCTL_READRQ
)) {
882 ((le16_to_cpu(*ctrl
) & PCI_EXP_DEVCTL_READRQ
) >> 12);
883 readrq
= max(readrq
, pcie_get_mps(vdev
->pdev
));
885 pcie_set_readrq(vdev
->pdev
, readrq
);
891 /* Permissions for PCI Express capability */
892 static int __init
init_pci_cap_exp_perm(struct perm_bits
*perm
)
894 /* Alloc largest of possible sizes */
895 if (alloc_perm_bits(perm
, PCI_CAP_EXP_ENDPOINT_SIZEOF_V2
))
898 perm
->writefn
= vfio_exp_config_write
;
900 p_setb(perm
, PCI_CAP_LIST_NEXT
, (u8
)ALL_VIRT
, NO_WRITE
);
903 * Allow writes to device control fields, except devctl_phantom,
904 * which could confuse IOMMU, MPS, which can break communication
905 * with other physical devices, and the ARI bit in devctl2, which
906 * is set at probe time. FLR and MRRS get virtualized via our
909 p_setw(perm
, PCI_EXP_DEVCTL
,
910 PCI_EXP_DEVCTL_BCR_FLR
| PCI_EXP_DEVCTL_PAYLOAD
|
911 PCI_EXP_DEVCTL_READRQ
, ~PCI_EXP_DEVCTL_PHANTOM
);
912 p_setw(perm
, PCI_EXP_DEVCTL2
, NO_VIRT
, ~PCI_EXP_DEVCTL2_ARI
);
916 static int vfio_af_config_write(struct vfio_pci_device
*vdev
, int pos
,
917 int count
, struct perm_bits
*perm
,
918 int offset
, __le32 val
)
920 u8
*ctrl
= vdev
->vconfig
+ pos
- offset
+ PCI_AF_CTRL
;
922 count
= vfio_default_config_write(vdev
, pos
, count
, perm
, offset
, val
);
927 * The FLR bit is virtualized, if set and the device supports AF
928 * FLR, issue a reset_function. Regardless, clear the bit, the spec
929 * requires it to be always read as zero. NB, reset_function might
930 * not use an AF FLR, we don't have that level of granularity.
932 if (*ctrl
& PCI_AF_CTRL_FLR
) {
936 *ctrl
&= ~PCI_AF_CTRL_FLR
;
938 ret
= pci_user_read_config_byte(vdev
->pdev
,
939 pos
- offset
+ PCI_AF_CAP
,
942 if (!ret
&& (cap
& PCI_AF_CAP_FLR
) && (cap
& PCI_AF_CAP_TP
)) {
943 vfio_pci_zap_and_down_write_memory_lock(vdev
);
944 pci_try_reset_function(vdev
->pdev
);
945 up_write(&vdev
->memory_lock
);
952 /* Permissions for Advanced Function capability */
953 static int __init
init_pci_cap_af_perm(struct perm_bits
*perm
)
955 if (alloc_perm_bits(perm
, pci_cap_length
[PCI_CAP_ID_AF
]))
958 perm
->writefn
= vfio_af_config_write
;
960 p_setb(perm
, PCI_CAP_LIST_NEXT
, (u8
)ALL_VIRT
, NO_WRITE
);
961 p_setb(perm
, PCI_AF_CTRL
, PCI_AF_CTRL_FLR
, PCI_AF_CTRL_FLR
);
965 /* Permissions for Advanced Error Reporting extended capability */
966 static int __init
init_pci_ext_cap_err_perm(struct perm_bits
*perm
)
970 if (alloc_perm_bits(perm
, pci_ext_cap_length
[PCI_EXT_CAP_ID_ERR
]))
974 * Virtualize the first dword of all express capabilities
975 * because it includes the next pointer. This lets us later
976 * remove capabilities from the chain if we need to.
978 p_setd(perm
, 0, ALL_VIRT
, NO_WRITE
);
980 /* Writable bits mask */
981 mask
= PCI_ERR_UNC_UND
| /* Undefined */
982 PCI_ERR_UNC_DLP
| /* Data Link Protocol */
983 PCI_ERR_UNC_SURPDN
| /* Surprise Down */
984 PCI_ERR_UNC_POISON_TLP
| /* Poisoned TLP */
985 PCI_ERR_UNC_FCP
| /* Flow Control Protocol */
986 PCI_ERR_UNC_COMP_TIME
| /* Completion Timeout */
987 PCI_ERR_UNC_COMP_ABORT
| /* Completer Abort */
988 PCI_ERR_UNC_UNX_COMP
| /* Unexpected Completion */
989 PCI_ERR_UNC_RX_OVER
| /* Receiver Overflow */
990 PCI_ERR_UNC_MALF_TLP
| /* Malformed TLP */
991 PCI_ERR_UNC_ECRC
| /* ECRC Error Status */
992 PCI_ERR_UNC_UNSUP
| /* Unsupported Request */
993 PCI_ERR_UNC_ACSV
| /* ACS Violation */
994 PCI_ERR_UNC_INTN
| /* internal error */
995 PCI_ERR_UNC_MCBTLP
| /* MC blocked TLP */
996 PCI_ERR_UNC_ATOMEG
| /* Atomic egress blocked */
997 PCI_ERR_UNC_TLPPRE
; /* TLP prefix blocked */
998 p_setd(perm
, PCI_ERR_UNCOR_STATUS
, NO_VIRT
, mask
);
999 p_setd(perm
, PCI_ERR_UNCOR_MASK
, NO_VIRT
, mask
);
1000 p_setd(perm
, PCI_ERR_UNCOR_SEVER
, NO_VIRT
, mask
);
1002 mask
= PCI_ERR_COR_RCVR
| /* Receiver Error Status */
1003 PCI_ERR_COR_BAD_TLP
| /* Bad TLP Status */
1004 PCI_ERR_COR_BAD_DLLP
| /* Bad DLLP Status */
1005 PCI_ERR_COR_REP_ROLL
| /* REPLAY_NUM Rollover */
1006 PCI_ERR_COR_REP_TIMER
| /* Replay Timer Timeout */
1007 PCI_ERR_COR_ADV_NFAT
| /* Advisory Non-Fatal */
1008 PCI_ERR_COR_INTERNAL
| /* Corrected Internal */
1009 PCI_ERR_COR_LOG_OVER
; /* Header Log Overflow */
1010 p_setd(perm
, PCI_ERR_COR_STATUS
, NO_VIRT
, mask
);
1011 p_setd(perm
, PCI_ERR_COR_MASK
, NO_VIRT
, mask
);
1013 mask
= PCI_ERR_CAP_ECRC_GENE
| /* ECRC Generation Enable */
1014 PCI_ERR_CAP_ECRC_CHKE
; /* ECRC Check Enable */
1015 p_setd(perm
, PCI_ERR_CAP
, NO_VIRT
, mask
);
1019 /* Permissions for Power Budgeting extended capability */
1020 static int __init
init_pci_ext_cap_pwr_perm(struct perm_bits
*perm
)
1022 if (alloc_perm_bits(perm
, pci_ext_cap_length
[PCI_EXT_CAP_ID_PWR
]))
1025 p_setd(perm
, 0, ALL_VIRT
, NO_WRITE
);
1027 /* Writing the data selector is OK, the info is still read-only */
1028 p_setb(perm
, PCI_PWR_DATA
, NO_VIRT
, (u8
)ALL_WRITE
);
1033 * Initialize the shared permission tables
1035 void vfio_pci_uninit_perm_bits(void)
1037 free_perm_bits(&cap_perms
[PCI_CAP_ID_BASIC
]);
1039 free_perm_bits(&cap_perms
[PCI_CAP_ID_PM
]);
1040 free_perm_bits(&cap_perms
[PCI_CAP_ID_VPD
]);
1041 free_perm_bits(&cap_perms
[PCI_CAP_ID_PCIX
]);
1042 free_perm_bits(&cap_perms
[PCI_CAP_ID_EXP
]);
1043 free_perm_bits(&cap_perms
[PCI_CAP_ID_AF
]);
1045 free_perm_bits(&ecap_perms
[PCI_EXT_CAP_ID_ERR
]);
1046 free_perm_bits(&ecap_perms
[PCI_EXT_CAP_ID_PWR
]);
1049 int __init
vfio_pci_init_perm_bits(void)
1053 /* Basic config space */
1054 ret
= init_pci_cap_basic_perm(&cap_perms
[PCI_CAP_ID_BASIC
]);
1057 ret
|= init_pci_cap_pm_perm(&cap_perms
[PCI_CAP_ID_PM
]);
1058 ret
|= init_pci_cap_vpd_perm(&cap_perms
[PCI_CAP_ID_VPD
]);
1059 ret
|= init_pci_cap_pcix_perm(&cap_perms
[PCI_CAP_ID_PCIX
]);
1060 cap_perms
[PCI_CAP_ID_VNDR
].writefn
= vfio_raw_config_write
;
1061 ret
|= init_pci_cap_exp_perm(&cap_perms
[PCI_CAP_ID_EXP
]);
1062 ret
|= init_pci_cap_af_perm(&cap_perms
[PCI_CAP_ID_AF
]);
1064 /* Extended capabilities */
1065 ret
|= init_pci_ext_cap_err_perm(&ecap_perms
[PCI_EXT_CAP_ID_ERR
]);
1066 ret
|= init_pci_ext_cap_pwr_perm(&ecap_perms
[PCI_EXT_CAP_ID_PWR
]);
1067 ecap_perms
[PCI_EXT_CAP_ID_VNDR
].writefn
= vfio_raw_config_write
;
1070 vfio_pci_uninit_perm_bits();
1075 static int vfio_find_cap_start(struct vfio_pci_device
*vdev
, int pos
)
1078 int base
= (pos
>= PCI_CFG_SPACE_SIZE
) ? PCI_CFG_SPACE_SIZE
:
1079 PCI_STD_HEADER_SIZEOF
;
1080 cap
= vdev
->pci_config_map
[pos
];
1082 if (cap
== PCI_CAP_ID_BASIC
)
1085 /* XXX Can we have to abutting capabilities of the same type? */
1086 while (pos
- 1 >= base
&& vdev
->pci_config_map
[pos
- 1] == cap
)
1092 static int vfio_msi_config_read(struct vfio_pci_device
*vdev
, int pos
,
1093 int count
, struct perm_bits
*perm
,
1094 int offset
, __le32
*val
)
1096 /* Update max available queue size from msi_qmax */
1097 if (offset
<= PCI_MSI_FLAGS
&& offset
+ count
>= PCI_MSI_FLAGS
) {
1101 start
= vfio_find_cap_start(vdev
, pos
);
1103 flags
= (__le16
*)&vdev
->vconfig
[start
];
1105 *flags
&= cpu_to_le16(~PCI_MSI_FLAGS_QMASK
);
1106 *flags
|= cpu_to_le16(vdev
->msi_qmax
<< 1);
1109 return vfio_default_config_read(vdev
, pos
, count
, perm
, offset
, val
);
1112 static int vfio_msi_config_write(struct vfio_pci_device
*vdev
, int pos
,
1113 int count
, struct perm_bits
*perm
,
1114 int offset
, __le32 val
)
1116 count
= vfio_default_config_write(vdev
, pos
, count
, perm
, offset
, val
);
1120 /* Fixup and write configured queue size and enable to hardware */
1121 if (offset
<= PCI_MSI_FLAGS
&& offset
+ count
>= PCI_MSI_FLAGS
) {
1126 start
= vfio_find_cap_start(vdev
, pos
);
1128 pflags
= (__le16
*)&vdev
->vconfig
[start
+ PCI_MSI_FLAGS
];
1130 flags
= le16_to_cpu(*pflags
);
1132 /* MSI is enabled via ioctl */
1134 flags
&= ~PCI_MSI_FLAGS_ENABLE
;
1136 /* Check queue size */
1137 if ((flags
& PCI_MSI_FLAGS_QSIZE
) >> 4 > vdev
->msi_qmax
) {
1138 flags
&= ~PCI_MSI_FLAGS_QSIZE
;
1139 flags
|= vdev
->msi_qmax
<< 4;
1142 /* Write back to virt and to hardware */
1143 *pflags
= cpu_to_le16(flags
);
1144 ret
= pci_user_write_config_word(vdev
->pdev
,
1145 start
+ PCI_MSI_FLAGS
,
1155 * MSI determination is per-device, so this routine gets used beyond
1156 * initialization time. Don't add __init
1158 static int init_pci_cap_msi_perm(struct perm_bits
*perm
, int len
, u16 flags
)
1160 if (alloc_perm_bits(perm
, len
))
1163 perm
->readfn
= vfio_msi_config_read
;
1164 perm
->writefn
= vfio_msi_config_write
;
1166 p_setb(perm
, PCI_CAP_LIST_NEXT
, (u8
)ALL_VIRT
, NO_WRITE
);
1169 * The upper byte of the control register is reserved,
1170 * just setup the lower byte.
1172 p_setb(perm
, PCI_MSI_FLAGS
, (u8
)ALL_VIRT
, (u8
)ALL_WRITE
);
1173 p_setd(perm
, PCI_MSI_ADDRESS_LO
, ALL_VIRT
, ALL_WRITE
);
1174 if (flags
& PCI_MSI_FLAGS_64BIT
) {
1175 p_setd(perm
, PCI_MSI_ADDRESS_HI
, ALL_VIRT
, ALL_WRITE
);
1176 p_setw(perm
, PCI_MSI_DATA_64
, (u16
)ALL_VIRT
, (u16
)ALL_WRITE
);
1177 if (flags
& PCI_MSI_FLAGS_MASKBIT
) {
1178 p_setd(perm
, PCI_MSI_MASK_64
, NO_VIRT
, ALL_WRITE
);
1179 p_setd(perm
, PCI_MSI_PENDING_64
, NO_VIRT
, ALL_WRITE
);
1182 p_setw(perm
, PCI_MSI_DATA_32
, (u16
)ALL_VIRT
, (u16
)ALL_WRITE
);
1183 if (flags
& PCI_MSI_FLAGS_MASKBIT
) {
1184 p_setd(perm
, PCI_MSI_MASK_32
, NO_VIRT
, ALL_WRITE
);
1185 p_setd(perm
, PCI_MSI_PENDING_32
, NO_VIRT
, ALL_WRITE
);
1191 /* Determine MSI CAP field length; initialize msi_perms on 1st call per vdev */
1192 static int vfio_msi_cap_len(struct vfio_pci_device
*vdev
, u8 pos
)
1194 struct pci_dev
*pdev
= vdev
->pdev
;
1198 ret
= pci_read_config_word(pdev
, pos
+ PCI_MSI_FLAGS
, &flags
);
1200 return pcibios_err_to_errno(ret
);
1202 len
= 10; /* Minimum size */
1203 if (flags
& PCI_MSI_FLAGS_64BIT
)
1205 if (flags
& PCI_MSI_FLAGS_MASKBIT
)
1211 vdev
->msi_perm
= kmalloc(sizeof(struct perm_bits
), GFP_KERNEL
);
1212 if (!vdev
->msi_perm
)
1215 ret
= init_pci_cap_msi_perm(vdev
->msi_perm
, len
, flags
);
1217 kfree(vdev
->msi_perm
);
1224 /* Determine extended capability length for VC (2 & 9) and MFVC */
1225 static int vfio_vc_cap_len(struct vfio_pci_device
*vdev
, u16 pos
)
1227 struct pci_dev
*pdev
= vdev
->pdev
;
1229 int ret
, evcc
, phases
, vc_arb
;
1230 int len
= PCI_CAP_VC_BASE_SIZEOF
;
1232 ret
= pci_read_config_dword(pdev
, pos
+ PCI_VC_PORT_CAP1
, &tmp
);
1234 return pcibios_err_to_errno(ret
);
1236 evcc
= tmp
& PCI_VC_CAP1_EVCC
; /* extended vc count */
1237 ret
= pci_read_config_dword(pdev
, pos
+ PCI_VC_PORT_CAP2
, &tmp
);
1239 return pcibios_err_to_errno(ret
);
1241 if (tmp
& PCI_VC_CAP2_128_PHASE
)
1243 else if (tmp
& PCI_VC_CAP2_64_PHASE
)
1245 else if (tmp
& PCI_VC_CAP2_32_PHASE
)
1250 vc_arb
= phases
* 4;
1253 * Port arbitration tables are root & switch only;
1254 * function arbitration tables are function 0 only.
1255 * In either case, we'll never let user write them so
1256 * we don't care how big they are
1258 len
+= (1 + evcc
) * PCI_CAP_VC_PER_VC_SIZEOF
;
1260 len
= round_up(len
, 16);
1266 static int vfio_cap_len(struct vfio_pci_device
*vdev
, u8 cap
, u8 pos
)
1268 struct pci_dev
*pdev
= vdev
->pdev
;
1275 case PCI_CAP_ID_MSI
:
1276 return vfio_msi_cap_len(vdev
, pos
);
1277 case PCI_CAP_ID_PCIX
:
1278 ret
= pci_read_config_word(pdev
, pos
+ PCI_X_CMD
, &word
);
1280 return pcibios_err_to_errno(ret
);
1282 if (PCI_X_CMD_VERSION(word
)) {
1283 if (pdev
->cfg_size
> PCI_CFG_SPACE_SIZE
) {
1284 /* Test for extended capabilities */
1285 pci_read_config_dword(pdev
, PCI_CFG_SPACE_SIZE
,
1287 vdev
->extended_caps
= (dword
!= 0);
1289 return PCI_CAP_PCIX_SIZEOF_V2
;
1291 return PCI_CAP_PCIX_SIZEOF_V0
;
1292 case PCI_CAP_ID_VNDR
:
1293 /* length follows next field */
1294 ret
= pci_read_config_byte(pdev
, pos
+ PCI_CAP_FLAGS
, &byte
);
1296 return pcibios_err_to_errno(ret
);
1299 case PCI_CAP_ID_EXP
:
1300 if (pdev
->cfg_size
> PCI_CFG_SPACE_SIZE
) {
1301 /* Test for extended capabilities */
1302 pci_read_config_dword(pdev
, PCI_CFG_SPACE_SIZE
, &dword
);
1303 vdev
->extended_caps
= (dword
!= 0);
1306 /* length based on version and type */
1307 if ((pcie_caps_reg(pdev
) & PCI_EXP_FLAGS_VERS
) == 1) {
1308 if (pci_pcie_type(pdev
) == PCI_EXP_TYPE_RC_END
)
1309 return 0xc; /* "All Devices" only, no link */
1310 return PCI_CAP_EXP_ENDPOINT_SIZEOF_V1
;
1312 if (pci_pcie_type(pdev
) == PCI_EXP_TYPE_RC_END
)
1313 return 0x2c; /* No link */
1314 return PCI_CAP_EXP_ENDPOINT_SIZEOF_V2
;
1317 ret
= pci_read_config_byte(pdev
, pos
+ 3, &byte
);
1319 return pcibios_err_to_errno(ret
);
1321 return (byte
& HT_3BIT_CAP_MASK
) ?
1322 HT_CAP_SIZEOF_SHORT
: HT_CAP_SIZEOF_LONG
;
1323 case PCI_CAP_ID_SATA
:
1324 ret
= pci_read_config_byte(pdev
, pos
+ PCI_SATA_REGS
, &byte
);
1326 return pcibios_err_to_errno(ret
);
1328 byte
&= PCI_SATA_REGS_MASK
;
1329 if (byte
== PCI_SATA_REGS_INLINE
)
1330 return PCI_SATA_SIZEOF_LONG
;
1332 return PCI_SATA_SIZEOF_SHORT
;
1334 pci_warn(pdev
, "%s: unknown length for PCI cap %#x@%#x\n",
1335 __func__
, cap
, pos
);
1341 static int vfio_ext_cap_len(struct vfio_pci_device
*vdev
, u16 ecap
, u16 epos
)
1343 struct pci_dev
*pdev
= vdev
->pdev
;
1349 case PCI_EXT_CAP_ID_VNDR
:
1350 ret
= pci_read_config_dword(pdev
, epos
+ PCI_VSEC_HDR
, &dword
);
1352 return pcibios_err_to_errno(ret
);
1354 return dword
>> PCI_VSEC_HDR_LEN_SHIFT
;
1355 case PCI_EXT_CAP_ID_VC
:
1356 case PCI_EXT_CAP_ID_VC9
:
1357 case PCI_EXT_CAP_ID_MFVC
:
1358 return vfio_vc_cap_len(vdev
, epos
);
1359 case PCI_EXT_CAP_ID_ACS
:
1360 ret
= pci_read_config_byte(pdev
, epos
+ PCI_ACS_CAP
, &byte
);
1362 return pcibios_err_to_errno(ret
);
1364 if (byte
& PCI_ACS_EC
) {
1367 ret
= pci_read_config_byte(pdev
,
1368 epos
+ PCI_ACS_EGRESS_BITS
,
1371 return pcibios_err_to_errno(ret
);
1373 bits
= byte
? round_up(byte
, 32) : 256;
1374 return 8 + (bits
/ 8);
1378 case PCI_EXT_CAP_ID_REBAR
:
1379 ret
= pci_read_config_byte(pdev
, epos
+ PCI_REBAR_CTRL
, &byte
);
1381 return pcibios_err_to_errno(ret
);
1383 byte
&= PCI_REBAR_CTRL_NBAR_MASK
;
1384 byte
>>= PCI_REBAR_CTRL_NBAR_SHIFT
;
1386 return 4 + (byte
* 8);
1387 case PCI_EXT_CAP_ID_DPA
:
1388 ret
= pci_read_config_byte(pdev
, epos
+ PCI_DPA_CAP
, &byte
);
1390 return pcibios_err_to_errno(ret
);
1392 byte
&= PCI_DPA_CAP_SUBSTATE_MASK
;
1393 return PCI_DPA_BASE_SIZEOF
+ byte
+ 1;
1394 case PCI_EXT_CAP_ID_TPH
:
1395 ret
= pci_read_config_dword(pdev
, epos
+ PCI_TPH_CAP
, &dword
);
1397 return pcibios_err_to_errno(ret
);
1399 if ((dword
& PCI_TPH_CAP_LOC_MASK
) == PCI_TPH_LOC_CAP
) {
1402 sts
= dword
& PCI_TPH_CAP_ST_MASK
;
1403 sts
>>= PCI_TPH_CAP_ST_SHIFT
;
1404 return PCI_TPH_BASE_SIZEOF
+ (sts
* 2) + 2;
1406 return PCI_TPH_BASE_SIZEOF
;
1408 pci_warn(pdev
, "%s: unknown length for PCI ecap %#x@%#x\n",
1409 __func__
, ecap
, epos
);
1415 static int vfio_fill_vconfig_bytes(struct vfio_pci_device
*vdev
,
1416 int offset
, int size
)
1418 struct pci_dev
*pdev
= vdev
->pdev
;
1422 * We try to read physical config space in the largest chunks
1423 * we can, assuming that all of the fields support dword access.
1424 * pci_save_state() makes this same assumption and seems to do ok.
1429 if (size
>= 4 && !(offset
% 4)) {
1430 __le32
*dwordp
= (__le32
*)&vdev
->vconfig
[offset
];
1433 ret
= pci_read_config_dword(pdev
, offset
, &dword
);
1436 *dwordp
= cpu_to_le32(dword
);
1438 } else if (size
>= 2 && !(offset
% 2)) {
1439 __le16
*wordp
= (__le16
*)&vdev
->vconfig
[offset
];
1442 ret
= pci_read_config_word(pdev
, offset
, &word
);
1445 *wordp
= cpu_to_le16(word
);
1448 u8
*byte
= &vdev
->vconfig
[offset
];
1449 ret
= pci_read_config_byte(pdev
, offset
, byte
);
1462 static int vfio_cap_init(struct vfio_pci_device
*vdev
)
1464 struct pci_dev
*pdev
= vdev
->pdev
;
1465 u8
*map
= vdev
->pci_config_map
;
1468 int loops
, ret
, caps
= 0;
1470 /* Any capabilities? */
1471 ret
= pci_read_config_word(pdev
, PCI_STATUS
, &status
);
1475 if (!(status
& PCI_STATUS_CAP_LIST
))
1476 return 0; /* Done */
1478 ret
= pci_read_config_byte(pdev
, PCI_CAPABILITY_LIST
, &pos
);
1482 /* Mark the previous position in case we want to skip a capability */
1483 prev
= &vdev
->vconfig
[PCI_CAPABILITY_LIST
];
1485 /* We can bound our loop, capabilities are dword aligned */
1486 loops
= (PCI_CFG_SPACE_SIZE
- PCI_STD_HEADER_SIZEOF
) / PCI_CAP_SIZEOF
;
1487 while (pos
&& loops
--) {
1491 ret
= pci_read_config_byte(pdev
, pos
, &cap
);
1495 ret
= pci_read_config_byte(pdev
,
1496 pos
+ PCI_CAP_LIST_NEXT
, &next
);
1501 * ID 0 is a NULL capability, conflicting with our fake
1502 * PCI_CAP_ID_BASIC. As it has no content, consider it
1505 if (cap
&& cap
<= PCI_CAP_ID_MAX
) {
1506 len
= pci_cap_length
[cap
];
1507 if (len
== 0xFF) { /* Variable length */
1508 len
= vfio_cap_len(vdev
, cap
, pos
);
1515 pci_info(pdev
, "%s: hiding cap %#x@%#x\n", __func__
,
1522 /* Sanity check, do we overlap other capabilities? */
1523 for (i
= 0; i
< len
; i
++) {
1524 if (likely(map
[pos
+ i
] == PCI_CAP_ID_INVALID
))
1527 pci_warn(pdev
, "%s: PCI config conflict @%#x, was cap %#x now cap %#x\n",
1528 __func__
, pos
+ i
, map
[pos
+ i
], cap
);
1531 BUILD_BUG_ON(PCI_CAP_ID_MAX
>= PCI_CAP_ID_INVALID_VIRT
);
1533 memset(map
+ pos
, cap
, len
);
1534 ret
= vfio_fill_vconfig_bytes(vdev
, pos
, len
);
1538 prev
= &vdev
->vconfig
[pos
+ PCI_CAP_LIST_NEXT
];
1543 /* If we didn't fill any capabilities, clear the status flag */
1545 __le16
*vstatus
= (__le16
*)&vdev
->vconfig
[PCI_STATUS
];
1546 *vstatus
&= ~cpu_to_le16(PCI_STATUS_CAP_LIST
);
1552 static int vfio_ecap_init(struct vfio_pci_device
*vdev
)
1554 struct pci_dev
*pdev
= vdev
->pdev
;
1555 u8
*map
= vdev
->pci_config_map
;
1557 __le32
*prev
= NULL
;
1558 int loops
, ret
, ecaps
= 0;
1560 if (!vdev
->extended_caps
)
1563 epos
= PCI_CFG_SPACE_SIZE
;
1565 loops
= (pdev
->cfg_size
- PCI_CFG_SPACE_SIZE
) / PCI_CAP_SIZEOF
;
1567 while (loops
-- && epos
>= PCI_CFG_SPACE_SIZE
) {
1571 bool hidden
= false;
1573 ret
= pci_read_config_dword(pdev
, epos
, &header
);
1577 ecap
= PCI_EXT_CAP_ID(header
);
1579 if (ecap
<= PCI_EXT_CAP_ID_MAX
) {
1580 len
= pci_ext_cap_length
[ecap
];
1582 len
= vfio_ext_cap_len(vdev
, ecap
, epos
);
1589 pci_info(pdev
, "%s: hiding ecap %#x@%#x\n",
1590 __func__
, ecap
, epos
);
1592 /* If not the first in the chain, we can skip over it */
1594 u32 val
= epos
= PCI_EXT_CAP_NEXT(header
);
1595 *prev
&= cpu_to_le32(~(0xffcU
<< 20));
1596 *prev
|= cpu_to_le32(val
<< 20);
1601 * Otherwise, fill in a placeholder, the direct
1602 * readfn will virtualize this automatically
1604 len
= PCI_CAP_SIZEOF
;
1608 for (i
= 0; i
< len
; i
++) {
1609 if (likely(map
[epos
+ i
] == PCI_CAP_ID_INVALID
))
1612 pci_warn(pdev
, "%s: PCI config conflict @%#x, was ecap %#x now ecap %#x\n",
1613 __func__
, epos
+ i
, map
[epos
+ i
], ecap
);
1617 * Even though ecap is 2 bytes, we're currently a long way
1618 * from exceeding 1 byte capabilities. If we ever make it
1619 * up to 0xFE we'll need to up this to a two-byte, byte map.
1621 BUILD_BUG_ON(PCI_EXT_CAP_ID_MAX
>= PCI_CAP_ID_INVALID_VIRT
);
1623 memset(map
+ epos
, ecap
, len
);
1624 ret
= vfio_fill_vconfig_bytes(vdev
, epos
, len
);
1629 * If we're just using this capability to anchor the list,
1630 * hide the real ID. Only count real ecaps. XXX PCI spec
1631 * indicates to use cap id = 0, version = 0, next = 0 if
1632 * ecaps are absent, hope users check all the way to next.
1635 *(__le32
*)&vdev
->vconfig
[epos
] &=
1636 cpu_to_le32((0xffcU
<< 20));
1640 prev
= (__le32
*)&vdev
->vconfig
[epos
];
1641 epos
= PCI_EXT_CAP_NEXT(header
);
1645 *(u32
*)&vdev
->vconfig
[PCI_CFG_SPACE_SIZE
] = 0;
1651 * Nag about hardware bugs, hopefully to have vendors fix them, but at least
1652 * to collect a list of dependencies for the VF INTx pin quirk below.
1654 static const struct pci_device_id known_bogus_vf_intx_pin
[] = {
1655 { PCI_DEVICE(PCI_VENDOR_ID_INTEL
, 0x270c) },
1660 * For each device we allocate a pci_config_map that indicates the
1661 * capability occupying each dword and thus the struct perm_bits we
1662 * use for read and write. We also allocate a virtualized config
1663 * space which tracks reads and writes to bits that we emulate for
1664 * the user. Initial values filled from device.
1666 * Using shared struct perm_bits between all vfio-pci devices saves
1667 * us from allocating cfg_size buffers for virt and write for every
1668 * device. We could remove vconfig and allocate individual buffers
1669 * for each area requiring emulated bits, but the array of pointers
1670 * would be comparable in size (at least for standard config space).
1672 int vfio_config_init(struct vfio_pci_device
*vdev
)
1674 struct pci_dev
*pdev
= vdev
->pdev
;
1679 * Config space, caps and ecaps are all dword aligned, so we could
1680 * use one byte per dword to record the type. However, there are
1681 * no requiremenst on the length of a capability, so the gap between
1682 * capabilities needs byte granularity.
1684 map
= kmalloc(pdev
->cfg_size
, GFP_KERNEL
);
1688 vconfig
= kmalloc(pdev
->cfg_size
, GFP_KERNEL
);
1694 vdev
->pci_config_map
= map
;
1695 vdev
->vconfig
= vconfig
;
1697 memset(map
, PCI_CAP_ID_BASIC
, PCI_STD_HEADER_SIZEOF
);
1698 memset(map
+ PCI_STD_HEADER_SIZEOF
, PCI_CAP_ID_INVALID
,
1699 pdev
->cfg_size
- PCI_STD_HEADER_SIZEOF
);
1701 ret
= vfio_fill_vconfig_bytes(vdev
, 0, PCI_STD_HEADER_SIZEOF
);
1705 vdev
->bardirty
= true;
1708 * XXX can we just pci_load_saved_state/pci_restore_state?
1709 * may need to rebuild vconfig after that
1712 /* For restore after reset */
1713 vdev
->rbar
[0] = le32_to_cpu(*(__le32
*)&vconfig
[PCI_BASE_ADDRESS_0
]);
1714 vdev
->rbar
[1] = le32_to_cpu(*(__le32
*)&vconfig
[PCI_BASE_ADDRESS_1
]);
1715 vdev
->rbar
[2] = le32_to_cpu(*(__le32
*)&vconfig
[PCI_BASE_ADDRESS_2
]);
1716 vdev
->rbar
[3] = le32_to_cpu(*(__le32
*)&vconfig
[PCI_BASE_ADDRESS_3
]);
1717 vdev
->rbar
[4] = le32_to_cpu(*(__le32
*)&vconfig
[PCI_BASE_ADDRESS_4
]);
1718 vdev
->rbar
[5] = le32_to_cpu(*(__le32
*)&vconfig
[PCI_BASE_ADDRESS_5
]);
1719 vdev
->rbar
[6] = le32_to_cpu(*(__le32
*)&vconfig
[PCI_ROM_ADDRESS
]);
1721 if (pdev
->is_virtfn
) {
1722 *(__le16
*)&vconfig
[PCI_VENDOR_ID
] = cpu_to_le16(pdev
->vendor
);
1723 *(__le16
*)&vconfig
[PCI_DEVICE_ID
] = cpu_to_le16(pdev
->device
);
1726 * Per SR-IOV spec rev 1.1, 3.4.1.18 the interrupt pin register
1727 * does not apply to VFs and VFs must implement this register
1728 * as read-only with value zero. Userspace is not readily able
1729 * to identify whether a device is a VF and thus that the pin
1730 * definition on the device is bogus should it violate this
1731 * requirement. We already virtualize the pin register for
1732 * other purposes, so we simply need to replace the bogus value
1733 * and consider VFs when we determine INTx IRQ count.
1735 if (vconfig
[PCI_INTERRUPT_PIN
] &&
1736 !pci_match_id(known_bogus_vf_intx_pin
, pdev
))
1738 "Hardware bug: VF reports bogus INTx pin %d\n",
1739 vconfig
[PCI_INTERRUPT_PIN
]);
1741 vconfig
[PCI_INTERRUPT_PIN
] = 0; /* Gratuitous for good VFs */
1743 if (pdev
->no_command_memory
) {
1745 * VFs and devices that set pdev->no_command_memory do not
1746 * implement the memory enable bit of the COMMAND register
1747 * therefore we'll not have it set in our initial copy of
1748 * config space after pci_enable_device(). For consistency
1749 * with PFs, set the virtual enable bit here.
1751 *(__le16
*)&vconfig
[PCI_COMMAND
] |=
1752 cpu_to_le16(PCI_COMMAND_MEMORY
);
1755 if (!IS_ENABLED(CONFIG_VFIO_PCI_INTX
) || vdev
->nointx
)
1756 vconfig
[PCI_INTERRUPT_PIN
] = 0;
1758 ret
= vfio_cap_init(vdev
);
1762 ret
= vfio_ecap_init(vdev
);
1770 vdev
->pci_config_map
= NULL
;
1772 vdev
->vconfig
= NULL
;
1773 return pcibios_err_to_errno(ret
);
1776 void vfio_config_free(struct vfio_pci_device
*vdev
)
1778 kfree(vdev
->vconfig
);
1779 vdev
->vconfig
= NULL
;
1780 kfree(vdev
->pci_config_map
);
1781 vdev
->pci_config_map
= NULL
;
1782 if (vdev
->msi_perm
) {
1783 free_perm_bits(vdev
->msi_perm
);
1784 kfree(vdev
->msi_perm
);
1785 vdev
->msi_perm
= NULL
;
1790 * Find the remaining number of bytes in a dword that match the given
1791 * position. Stop at either the end of the capability or the dword boundary.
1793 static size_t vfio_pci_cap_remaining_dword(struct vfio_pci_device
*vdev
,
1796 u8 cap
= vdev
->pci_config_map
[pos
];
1799 for (i
= 1; (pos
+ i
) % 4 && vdev
->pci_config_map
[pos
+ i
] == cap
; i
++)
1805 static ssize_t
vfio_config_do_rw(struct vfio_pci_device
*vdev
, char __user
*buf
,
1806 size_t count
, loff_t
*ppos
, bool iswrite
)
1808 struct pci_dev
*pdev
= vdev
->pdev
;
1809 struct perm_bits
*perm
;
1811 int cap_start
= 0, offset
;
1815 if (*ppos
< 0 || *ppos
>= pdev
->cfg_size
||
1816 *ppos
+ count
> pdev
->cfg_size
)
1820 * Chop accesses into aligned chunks containing no more than a
1821 * single capability. Caller increments to the next chunk.
1823 count
= min(count
, vfio_pci_cap_remaining_dword(vdev
, *ppos
));
1824 if (count
>= 4 && !(*ppos
% 4))
1826 else if (count
>= 2 && !(*ppos
% 2))
1833 cap_id
= vdev
->pci_config_map
[*ppos
];
1835 if (cap_id
== PCI_CAP_ID_INVALID
) {
1836 perm
= &unassigned_perms
;
1838 } else if (cap_id
== PCI_CAP_ID_INVALID_VIRT
) {
1842 if (*ppos
>= PCI_CFG_SPACE_SIZE
) {
1843 WARN_ON(cap_id
> PCI_EXT_CAP_ID_MAX
);
1845 perm
= &ecap_perms
[cap_id
];
1846 cap_start
= vfio_find_cap_start(vdev
, *ppos
);
1848 WARN_ON(cap_id
> PCI_CAP_ID_MAX
);
1850 perm
= &cap_perms
[cap_id
];
1852 if (cap_id
== PCI_CAP_ID_MSI
)
1853 perm
= vdev
->msi_perm
;
1855 if (cap_id
> PCI_CAP_ID_BASIC
)
1856 cap_start
= vfio_find_cap_start(vdev
, *ppos
);
1860 WARN_ON(!cap_start
&& cap_id
!= PCI_CAP_ID_BASIC
);
1861 WARN_ON(cap_start
> *ppos
);
1863 offset
= *ppos
- cap_start
;
1869 if (copy_from_user(&val
, buf
, count
))
1872 ret
= perm
->writefn(vdev
, *ppos
, count
, perm
, offset
, val
);
1875 ret
= perm
->readfn(vdev
, *ppos
, count
,
1876 perm
, offset
, &val
);
1881 if (copy_to_user(buf
, &val
, count
))
1888 ssize_t
vfio_pci_config_rw(struct vfio_pci_device
*vdev
, char __user
*buf
,
1889 size_t count
, loff_t
*ppos
, bool iswrite
)
1895 pos
&= VFIO_PCI_OFFSET_MASK
;
1898 ret
= vfio_config_do_rw(vdev
, buf
, count
, &pos
, iswrite
);