1 /* SPDX-License-Identifier: BSD-3-Clause
2 * Copyright (c) 2018, Microsoft Corporation.
16 #include <rte_memory.h>
17 #include <rte_eal_memconfig.h>
18 #include <rte_common.h>
19 #include <rte_malloc.h>
20 #include <rte_bus_vmbus.h>
21 #include <rte_string_fns.h>
25 /** Pathname of VMBUS devices directory. */
26 #define SYSFS_VMBUS_DEVICES "/sys/bus/vmbus/devices"
28 static void *vmbus_map_addr;
30 /* Control interrupts */
31 void vmbus_uio_irq_control(struct rte_vmbus_device *dev, int32_t onoff)
33 if (write(dev->intr_handle.fd, &onoff, sizeof(onoff)) < 0) {
34 VMBUS_LOG(ERR, "cannot write to %d:%s",
35 dev->intr_handle.fd, strerror(errno));
39 int vmbus_uio_irq_read(struct rte_vmbus_device *dev)
44 cc = read(dev->intr_handle.fd, &count, sizeof(count));
45 if (cc < (int)sizeof(count)) {
47 VMBUS_LOG(ERR, "IRQ read failed %s",
51 VMBUS_LOG(ERR, "can't read IRQ count");
59 vmbus_uio_free_resource(struct rte_vmbus_device *dev,
60 struct mapped_vmbus_resource *uio_res)
64 if (dev->intr_handle.uio_cfg_fd >= 0) {
65 close(dev->intr_handle.uio_cfg_fd);
66 dev->intr_handle.uio_cfg_fd = -1;
69 if (dev->intr_handle.fd >= 0) {
70 close(dev->intr_handle.fd);
71 dev->intr_handle.fd = -1;
72 dev->intr_handle.type = RTE_INTR_HANDLE_UNKNOWN;
77 vmbus_uio_alloc_resource(struct rte_vmbus_device *dev,
78 struct mapped_vmbus_resource **uio_res)
80 char devname[PATH_MAX]; /* contains the /dev/uioX */
82 /* save fd if in primary process */
83 snprintf(devname, sizeof(devname), "/dev/uio%u", dev->uio_num);
84 dev->intr_handle.fd = open(devname, O_RDWR);
85 if (dev->intr_handle.fd < 0) {
86 VMBUS_LOG(ERR, "Cannot open %s: %s",
87 devname, strerror(errno));
90 dev->intr_handle.type = RTE_INTR_HANDLE_UIO_INTX;
92 /* allocate the mapping details for secondary processes*/
93 *uio_res = rte_zmalloc("UIO_RES", sizeof(**uio_res), 0);
94 if (*uio_res == NULL) {
95 VMBUS_LOG(ERR, "cannot store uio mmap details");
99 strlcpy((*uio_res)->path, devname, PATH_MAX);
100 rte_uuid_copy((*uio_res)->id, dev->device_id);
105 vmbus_uio_free_resource(dev, *uio_res);
110 find_max_end_va(const struct rte_memseg_list *msl, void *arg)
112 size_t sz = msl->memseg_arr.len * msl->page_sz;
113 void *end_va = RTE_PTR_ADD(msl->base_va, sz);
116 if (*max_va < end_va)
122 * TODO: this should be part of memseg api.
123 * code is duplicated from PCI.
126 vmbus_find_max_end_va(void)
130 rte_memseg_list_walk(find_max_end_va, &va);
135 vmbus_uio_map_resource_by_index(struct rte_vmbus_device *dev, int idx,
136 struct mapped_vmbus_resource *uio_res,
139 size_t size = dev->resource[idx].len;
140 struct vmbus_map *maps = uio_res->maps;
145 /* devname for mmap */
146 fd = open(uio_res->path, O_RDWR);
148 VMBUS_LOG(ERR, "Cannot open %s: %s",
149 uio_res->path, strerror(errno));
153 /* try mapping somewhere close to the end of hugepages */
154 if (vmbus_map_addr == NULL)
155 vmbus_map_addr = vmbus_find_max_end_va();
157 /* offset is special in uio it indicates which resource */
158 offset = idx * PAGE_SIZE;
160 mapaddr = vmbus_map_resource(vmbus_map_addr, fd, offset, size, flags);
163 if (mapaddr == MAP_FAILED)
166 dev->resource[idx].addr = mapaddr;
167 vmbus_map_addr = RTE_PTR_ADD(mapaddr, size);
169 /* Record result of sucessful mapping for use by secondary */
170 maps[idx].addr = mapaddr;
171 maps[idx].size = size;
176 static int vmbus_uio_map_primary(struct vmbus_channel *chan,
177 void **ring_buf, uint32_t *ring_size)
179 struct mapped_vmbus_resource *uio_res;
181 uio_res = vmbus_uio_find_resource(chan->device);
183 VMBUS_LOG(ERR, "can not find resources!");
187 if (uio_res->nb_maps < VMBUS_MAX_RESOURCE) {
188 VMBUS_LOG(ERR, "VMBUS: only %u resources found!",
193 *ring_size = uio_res->maps[HV_TXRX_RING_MAP].size / 2;
194 *ring_buf = uio_res->maps[HV_TXRX_RING_MAP].addr;
198 static int vmbus_uio_map_subchan(const struct rte_vmbus_device *dev,
199 const struct vmbus_channel *chan,
200 void **ring_buf, uint32_t *ring_size)
202 char ring_path[PATH_MAX];
208 snprintf(ring_path, sizeof(ring_path),
209 "%s/%s/channels/%u/ring",
210 SYSFS_VMBUS_DEVICES, dev->device.name,
213 fd = open(ring_path, O_RDWR);
215 VMBUS_LOG(ERR, "Cannot open %s: %s",
216 ring_path, strerror(errno));
220 if (fstat(fd, &sb) < 0) {
221 VMBUS_LOG(ERR, "Cannot state %s: %s",
222 ring_path, strerror(errno));
226 file_size = sb.st_size;
228 if (file_size == 0 || (file_size & (PAGE_SIZE - 1))) {
229 VMBUS_LOG(ERR, "incorrect size %s: %zu",
230 ring_path, file_size);
236 mapaddr = vmbus_map_resource(vmbus_map_addr, fd,
240 if (mapaddr == MAP_FAILED)
243 *ring_size = file_size / 2;
246 vmbus_map_addr = RTE_PTR_ADD(ring_buf, file_size);
251 vmbus_uio_map_secondary_subchan(const struct rte_vmbus_device *dev,
252 const struct vmbus_channel *chan)
254 const struct vmbus_br *br = &chan->txbr;
255 char ring_path[PATH_MAX];
256 void *mapaddr, *ring_buf;
260 snprintf(ring_path, sizeof(ring_path),
261 "%s/%s/channels/%u/ring",
262 SYSFS_VMBUS_DEVICES, dev->device.name,
266 ring_size = br->dsize + sizeof(struct vmbus_bufring);
267 VMBUS_LOG(INFO, "secondary ring_buf %p size %u",
268 ring_buf, ring_size);
270 fd = open(ring_path, O_RDWR);
272 VMBUS_LOG(ERR, "Cannot open %s: %s",
273 ring_path, strerror(errno));
277 mapaddr = vmbus_map_resource(ring_buf, fd, 0, 2 * ring_size, 0);
280 if (mapaddr == ring_buf)
283 if (mapaddr == MAP_FAILED)
285 "mmap subchan %u in secondary failed", chan->relid);
288 "mmap subchan %u in secondary address mismatch",
290 vmbus_unmap_resource(mapaddr, 2 * ring_size);
295 int vmbus_uio_map_rings(struct vmbus_channel *chan)
297 const struct rte_vmbus_device *dev = chan->device;
302 /* Primary channel */
303 if (chan->subchannel_id == 0)
304 ret = vmbus_uio_map_primary(chan, &ring_buf, &ring_size);
306 ret = vmbus_uio_map_subchan(dev, chan, &ring_buf, &ring_size);
311 vmbus_br_setup(&chan->txbr, ring_buf, ring_size);
312 vmbus_br_setup(&chan->rxbr, (char *)ring_buf + ring_size, ring_size);
316 static int vmbus_uio_sysfs_read(const char *dir, const char *name,
317 unsigned long *val, unsigned long max_range)
323 snprintf(path, sizeof(path), "%s/%s", dir, name);
324 f = fopen(path, "r");
326 VMBUS_LOG(ERR, "can't open %s:%s",
327 path, strerror(errno));
331 if (fscanf(f, "%lu", val) != 1)
333 else if (*val > max_range)
342 static bool vmbus_uio_ring_present(const struct rte_vmbus_device *dev,
345 char ring_path[PATH_MAX];
347 /* Check if kernel has subchannel sysfs files */
348 snprintf(ring_path, sizeof(ring_path),
349 "%s/%s/channels/%u/ring",
350 SYSFS_VMBUS_DEVICES, dev->device.name, relid);
352 return access(ring_path, R_OK|W_OK) == 0;
355 bool vmbus_uio_subchannels_supported(const struct rte_vmbus_device *dev,
356 const struct vmbus_channel *chan)
358 return vmbus_uio_ring_present(dev, chan->relid);
361 static bool vmbus_isnew_subchannel(struct vmbus_channel *primary,
364 const struct vmbus_channel *c;
366 STAILQ_FOREACH(c, &primary->subchannel_list, next) {
373 int vmbus_uio_get_subchan(struct vmbus_channel *primary,
374 struct vmbus_channel **subchan)
376 const struct rte_vmbus_device *dev = primary->device;
377 char chan_path[PATH_MAX], subchan_path[PATH_MAX];
382 snprintf(chan_path, sizeof(chan_path),
384 SYSFS_VMBUS_DEVICES, dev->device.name);
386 chan_dir = opendir(chan_path);
388 VMBUS_LOG(ERR, "cannot open %s: %s",
389 chan_path, strerror(errno));
393 while ((ent = readdir(chan_dir))) {
394 unsigned long relid, subid, monid;
397 if (ent->d_name[0] == '.')
401 relid = strtoul(ent->d_name, &endp, 0);
402 if (*endp || errno != 0 || relid > UINT16_MAX) {
403 VMBUS_LOG(NOTICE, "not a valid channel relid: %s",
408 if (!vmbus_isnew_subchannel(primary, relid)) {
409 VMBUS_LOG(DEBUG, "skip already found channel: %lu",
414 if (!vmbus_uio_ring_present(dev, relid)) {
415 VMBUS_LOG(DEBUG, "ring mmap not found (yet) for: %lu",
420 snprintf(subchan_path, sizeof(subchan_path), "%s/%lu",
422 err = vmbus_uio_sysfs_read(subchan_path, "subchannel_id",
425 VMBUS_LOG(NOTICE, "no subchannel_id in %s:%s",
426 subchan_path, strerror(-err));
431 continue; /* skip primary channel */
433 err = vmbus_uio_sysfs_read(subchan_path, "monitor_id",
436 VMBUS_LOG(NOTICE, "no monitor_id in %s:%s",
437 subchan_path, strerror(-err));
441 err = vmbus_chan_create(dev, relid, subid, monid, subchan);
443 VMBUS_LOG(ERR, "subchannel setup failed");
450 return (ent == NULL) ? -ENOENT : 0;