1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright IBM Corp. 2020
4 *
5 * Author(s):
6 * Niklas Schnelle <schnelle@linux.ibm.com>
7 *
8 */
9
10 #define KMSG_COMPONENT "zpci"
11 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
12
13 #include <linux/kernel.h>
14 #include <linux/pci.h>
15
16 #include "pci_iov.h"
17
18 static struct resource iov_res = {
19 .name = "PCI IOV res",
20 .start = 0,
21 .end = -1,
22 .flags = IORESOURCE_MEM,
23 };
24
25 void zpci_iov_map_resources(struct pci_dev *pdev)
26 {
27 resource_size_t len;
28 int i;
29
30 for (i = 0; i < PCI_SRIOV_NUM_BARS; i++) {
31 int bar = i + PCI_IOV_RESOURCES;
32
33 len = pci_resource_len(pdev, bar);
34 if (!len)
35 continue;
36 pdev->resource[bar].parent = &iov_res;
37 }
38 }
39
40 void zpci_iov_remove_virtfn(struct pci_dev *pdev, int vfn)
41 {
42 pci_lock_rescan_remove();
43 /* Linux' vfid's start at 0 vfn at 1 */
44 pci_iov_remove_virtfn(pdev->physfn, vfn - 1);
45 pci_unlock_rescan_remove();
46 }
47
48 static int zpci_iov_link_virtfn(struct pci_dev *pdev, struct pci_dev *virtfn, int vfid)
49 {
50 int rc;
51
52 rc = pci_iov_sysfs_link(pdev, virtfn, vfid);
53 if (rc)
54 return rc;
55
56 virtfn->is_virtfn = 1;
57 virtfn->multifunction = 0;
58 virtfn->physfn = pci_dev_get(pdev);
59
60 return 0;
61 }
62
63 int zpci_iov_setup_virtfn(struct zpci_bus *zbus, struct pci_dev *virtfn, int vfn)
64 {
65 int i, cand_devfn;
66 struct zpci_dev *zdev;
67 struct pci_dev *pdev;
68 int vfid = vfn - 1; /* Linux' vfid's start at 0 vfn at 1*/
69 int rc = 0;
70
71 if (!zbus->multifunction)
72 return 0;
73
74 /* If the parent PF for the given VF is also configured in the
75 * instance, it must be on the same zbus.
76 * We can then identify the parent PF by checking what
77 * devfn the VF would have if it belonged to that PF using the PF's
78 * stride and offset. Only if this candidate devfn matches the
79 * actual devfn will we link both functions.
80 */
81 for (i = 0; i < ZPCI_FUNCTIONS_PER_BUS; i++) {
82 zdev = zbus->function[i];
83 if (zdev && zdev->is_physfn) {
84 pdev = pci_get_slot(zbus->bus, zdev->devfn);
85 if (!pdev)
86 continue;
87 cand_devfn = pci_iov_virtfn_devfn(pdev, vfid);
88 if (cand_devfn == virtfn->devfn) {
89 rc = zpci_iov_link_virtfn(pdev, virtfn, vfid);
90 /* balance pci_get_slot() */
91 pci_dev_put(pdev);
92 break;
93 }
94 /* balance pci_get_slot() */
95 pci_dev_put(pdev);
96 }
97 }
98 return rc;
99 }
100
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