xref: /dpdk/drivers/bus/pci/pci_common_uio.c (revision fd8c20aab4c2fe2c568455be4efab76db126791f)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright(c) 2010-2015 Intel Corporation
3  */
4 
5 #include <fcntl.h>
6 #include <string.h>
7 #include <unistd.h>
8 #include <sys/types.h>
9 #include <sys/stat.h>
10 #include <sys/mman.h>
11 
12 #include <rte_eal.h>
13 #include <rte_pci.h>
14 #include <rte_bus_pci.h>
15 #include <rte_tailq.h>
16 #include <rte_log.h>
17 #include <rte_malloc.h>
18 
19 #include "private.h"
20 
21 static struct rte_tailq_elem rte_uio_tailq = {
22 	.name = "UIO_RESOURCE_LIST",
23 };
24 EAL_REGISTER_TAILQ(rte_uio_tailq)
25 
26 static int
27 pci_uio_map_secondary(struct rte_pci_device *dev)
28 {
29 	int fd, i, j;
30 	struct mapped_pci_resource *uio_res;
31 	struct mapped_pci_res_list *uio_res_list =
32 			RTE_TAILQ_CAST(rte_uio_tailq.head, mapped_pci_res_list);
33 
34 	TAILQ_FOREACH(uio_res, uio_res_list, next) {
35 
36 		/* skip this element if it doesn't match our PCI address */
37 		if (rte_pci_addr_cmp(&uio_res->pci_addr, &dev->addr))
38 			continue;
39 
40 		for (i = 0; i != uio_res->nb_maps; i++) {
41 			/*
42 			 * open devname, to mmap it
43 			 */
44 			fd = open(uio_res->maps[i].path, O_RDWR);
45 			if (fd < 0) {
46 				RTE_LOG(ERR, EAL, "Cannot open %s: %s\n",
47 					uio_res->maps[i].path, strerror(errno));
48 				return -1;
49 			}
50 
51 			void *mapaddr = pci_map_resource(uio_res->maps[i].addr,
52 					fd, (off_t)uio_res->maps[i].offset,
53 					(size_t)uio_res->maps[i].size, 0);
54 			/* fd is not needed in slave process, close it */
55 			close(fd);
56 			if (mapaddr != uio_res->maps[i].addr) {
57 				RTE_LOG(ERR, EAL,
58 					"Cannot mmap device resource file %s to address: %p\n",
59 					uio_res->maps[i].path,
60 					uio_res->maps[i].addr);
61 				if (mapaddr != MAP_FAILED) {
62 					/* unmap addrs correctly mapped */
63 					for (j = 0; j < i; j++)
64 						pci_unmap_resource(
65 							uio_res->maps[j].addr,
66 							(size_t)uio_res->maps[j].size);
67 					/* unmap addr wrongly mapped */
68 					pci_unmap_resource(mapaddr,
69 						(size_t)uio_res->maps[i].size);
70 				}
71 				return -1;
72 			}
73 		}
74 		return 0;
75 	}
76 
77 	RTE_LOG(ERR, EAL, "Cannot find resource for device\n");
78 	return 1;
79 }
80 
81 /* map the PCI resource of a PCI device in virtual memory */
82 int
83 pci_uio_map_resource(struct rte_pci_device *dev)
84 {
85 	int i, map_idx = 0, ret;
86 	uint64_t phaddr;
87 	struct mapped_pci_resource *uio_res = NULL;
88 	struct mapped_pci_res_list *uio_res_list =
89 		RTE_TAILQ_CAST(rte_uio_tailq.head, mapped_pci_res_list);
90 
91 	dev->intr_handle.fd = -1;
92 	dev->intr_handle.uio_cfg_fd = -1;
93 
94 	/* secondary processes - use already recorded details */
95 	if (rte_eal_process_type() != RTE_PROC_PRIMARY)
96 		return pci_uio_map_secondary(dev);
97 
98 	/* allocate uio resource */
99 	ret = pci_uio_alloc_resource(dev, &uio_res);
100 	if (ret)
101 		return ret;
102 
103 	/* Map all BARs */
104 	for (i = 0; i != PCI_MAX_RESOURCE; i++) {
105 		/* skip empty BAR */
106 		phaddr = dev->mem_resource[i].phys_addr;
107 		if (phaddr == 0)
108 			continue;
109 
110 		ret = pci_uio_map_resource_by_index(dev, i,
111 				uio_res, map_idx);
112 		if (ret)
113 			goto error;
114 
115 		map_idx++;
116 	}
117 
118 	uio_res->nb_maps = map_idx;
119 
120 	TAILQ_INSERT_TAIL(uio_res_list, uio_res, next);
121 
122 	return 0;
123 error:
124 	for (i = 0; i < map_idx; i++) {
125 		pci_unmap_resource(uio_res->maps[i].addr,
126 				(size_t)uio_res->maps[i].size);
127 		rte_free(uio_res->maps[i].path);
128 	}
129 	pci_uio_free_resource(dev, uio_res);
130 	return -1;
131 }
132 
133 static void
134 pci_uio_unmap(struct mapped_pci_resource *uio_res)
135 {
136 	int i;
137 
138 	if (uio_res == NULL)
139 		return;
140 
141 	for (i = 0; i != uio_res->nb_maps; i++) {
142 		pci_unmap_resource(uio_res->maps[i].addr,
143 				(size_t)uio_res->maps[i].size);
144 		if (rte_eal_process_type() == RTE_PROC_PRIMARY)
145 			rte_free(uio_res->maps[i].path);
146 	}
147 }
148 
149 static struct mapped_pci_resource *
150 pci_uio_find_resource(struct rte_pci_device *dev)
151 {
152 	struct mapped_pci_resource *uio_res;
153 	struct mapped_pci_res_list *uio_res_list =
154 			RTE_TAILQ_CAST(rte_uio_tailq.head, mapped_pci_res_list);
155 
156 	if (dev == NULL)
157 		return NULL;
158 
159 	TAILQ_FOREACH(uio_res, uio_res_list, next) {
160 
161 		/* skip this element if it doesn't match our PCI address */
162 		if (!rte_pci_addr_cmp(&uio_res->pci_addr, &dev->addr))
163 			return uio_res;
164 	}
165 	return NULL;
166 }
167 
168 /* unmap the PCI resource of a PCI device in virtual memory */
169 void
170 pci_uio_unmap_resource(struct rte_pci_device *dev)
171 {
172 	struct mapped_pci_resource *uio_res;
173 	struct mapped_pci_res_list *uio_res_list =
174 			RTE_TAILQ_CAST(rte_uio_tailq.head, mapped_pci_res_list);
175 
176 	if (dev == NULL)
177 		return;
178 
179 	/* find an entry for the device */
180 	uio_res = pci_uio_find_resource(dev);
181 	if (uio_res == NULL)
182 		return;
183 
184 	/* secondary processes - just free maps */
185 	if (rte_eal_process_type() != RTE_PROC_PRIMARY)
186 		return pci_uio_unmap(uio_res);
187 
188 	TAILQ_REMOVE(uio_res_list, uio_res, next);
189 
190 	/* unmap all resources */
191 	pci_uio_unmap(uio_res);
192 
193 	/* free uio resource */
194 	rte_free(uio_res);
195 
196 	/* close fd if in primary process */
197 	close(dev->intr_handle.fd);
198 	if (dev->intr_handle.uio_cfg_fd >= 0) {
199 		close(dev->intr_handle.uio_cfg_fd);
200 		dev->intr_handle.uio_cfg_fd = -1;
201 	}
202 
203 	dev->intr_handle.fd = -1;
204 	dev->intr_handle.type = RTE_INTR_HANDLE_UNKNOWN;
205 }
206