2 * Copyright 2014 IBM Corp.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
10 #include <linux/pci.h>
11 #include <linux/slab.h>
12 #include <linux/file.h>
14 #include <linux/module.h>
15 #include <linux/mount.h>
16 #include <linux/sched/mm.h>
17 #include <linux/mmu_context.h>
22 * Since we want to track memory mappings to be able to force-unmap
23 * when the AFU is no longer reachable, we need an inode. For devices
24 * opened through the cxl user API, this is not a problem, but a
25 * userland process can also get a cxl fd through the cxl_get_fd()
26 * API, which is used by the cxlflash driver.
28 * Therefore we implement our own simple pseudo-filesystem and inode
29 * allocator. We don't use the anonymous inode, as we need the
30 * meta-data associated with it (address_space) and it is shared by
31 * other drivers/processes, so it could lead to cxl unmapping VMAs
32 * from random processes.
35 #define CXL_PSEUDO_FS_MAGIC 0x1697697f
37 static int cxl_fs_cnt;
38 static struct vfsmount *cxl_vfs_mount;
40 static const struct dentry_operations cxl_fs_dops = {
41 .d_dname = simple_dname,
44 static struct dentry *cxl_fs_mount(struct file_system_type *fs_type, int flags,
45 const char *dev_name, void *data)
47 return mount_pseudo(fs_type, "cxl:", NULL, &cxl_fs_dops,
51 static struct file_system_type cxl_fs_type = {
54 .mount = cxl_fs_mount,
55 .kill_sb = kill_anon_super,
59 void cxl_release_mapping(struct cxl_context *ctx)
61 if (ctx->kernelapi && ctx->mapping)
62 simple_release_fs(&cxl_vfs_mount, &cxl_fs_cnt);
65 static struct file *cxl_getfile(const char *name,
66 const struct file_operations *fops,
67 void *priv, int flags)
73 /* strongly inspired by anon_inode_getfile() */
75 if (fops->owner && !try_module_get(fops->owner))
76 return ERR_PTR(-ENOENT);
78 rc = simple_pin_fs(&cxl_fs_type, &cxl_vfs_mount, &cxl_fs_cnt);
80 pr_err("Cannot mount cxl pseudo filesystem: %d\n", rc);
85 inode = alloc_anon_inode(cxl_vfs_mount->mnt_sb);
87 file = ERR_CAST(inode);
91 file = alloc_file_pseudo(inode, cxl_vfs_mount, name,
92 flags & (O_ACCMODE | O_NONBLOCK), fops);
96 file->private_data = priv;
103 simple_release_fs(&cxl_vfs_mount, &cxl_fs_cnt);
105 module_put(fops->owner);
109 struct cxl_context *cxl_dev_context_init(struct pci_dev *dev)
112 struct cxl_context *ctx;
115 afu = cxl_pci_to_afu(dev);
117 return ERR_CAST(afu);
119 ctx = cxl_context_alloc();
121 return ERR_PTR(-ENOMEM);
123 ctx->kernelapi = true;
125 /* Make it a slave context. We can promote it later? */
126 rc = cxl_context_init(ctx, afu, false);
136 EXPORT_SYMBOL_GPL(cxl_dev_context_init);
138 struct cxl_context *cxl_get_context(struct pci_dev *dev)
140 return dev->dev.archdata.cxl_ctx;
142 EXPORT_SYMBOL_GPL(cxl_get_context);
144 int cxl_release_context(struct cxl_context *ctx)
146 if (ctx->status >= STARTED)
149 cxl_context_free(ctx);
153 EXPORT_SYMBOL_GPL(cxl_release_context);
155 static irq_hw_number_t cxl_find_afu_irq(struct cxl_context *ctx, int num)
160 for (r = 0; r < CXL_IRQ_RANGES; r++) {
161 range = ctx->irqs.range[r];
163 return ctx->irqs.offset[r] + num;
171 int cxl_set_priv(struct cxl_context *ctx, void *priv)
180 EXPORT_SYMBOL_GPL(cxl_set_priv);
182 void *cxl_get_priv(struct cxl_context *ctx)
185 return ERR_PTR(-EINVAL);
189 EXPORT_SYMBOL_GPL(cxl_get_priv);
191 int cxl_allocate_afu_irqs(struct cxl_context *ctx, int num)
194 irq_hw_number_t hwirq;
197 num = ctx->afu->pp_irqs;
198 res = afu_allocate_irqs(ctx, num);
202 if (!cpu_has_feature(CPU_FTR_HVMODE)) {
203 /* In a guest, the PSL interrupt is not multiplexed. It was
204 * allocated above, and we need to set its handler
206 hwirq = cxl_find_afu_irq(ctx, 0);
208 cxl_map_irq(ctx->afu->adapter, hwirq, cxl_ops->psl_interrupt, ctx, "psl");
211 if (ctx->status == STARTED) {
212 if (cxl_ops->update_ivtes)
213 cxl_ops->update_ivtes(ctx);
214 else WARN(1, "BUG: cxl_allocate_afu_irqs must be called prior to starting the context on this platform\n");
219 EXPORT_SYMBOL_GPL(cxl_allocate_afu_irqs);
221 void cxl_free_afu_irqs(struct cxl_context *ctx)
223 irq_hw_number_t hwirq;
226 if (!cpu_has_feature(CPU_FTR_HVMODE)) {
227 hwirq = cxl_find_afu_irq(ctx, 0);
229 virq = irq_find_mapping(NULL, hwirq);
231 cxl_unmap_irq(virq, ctx);
234 afu_irq_name_free(ctx);
235 cxl_ops->release_irq_ranges(&ctx->irqs, ctx->afu->adapter);
237 EXPORT_SYMBOL_GPL(cxl_free_afu_irqs);
239 int cxl_map_afu_irq(struct cxl_context *ctx, int num,
240 irq_handler_t handler, void *cookie, char *name)
242 irq_hw_number_t hwirq;
245 * Find interrupt we are to register.
247 hwirq = cxl_find_afu_irq(ctx, num);
251 return cxl_map_irq(ctx->afu->adapter, hwirq, handler, cookie, name);
253 EXPORT_SYMBOL_GPL(cxl_map_afu_irq);
255 void cxl_unmap_afu_irq(struct cxl_context *ctx, int num, void *cookie)
257 irq_hw_number_t hwirq;
260 hwirq = cxl_find_afu_irq(ctx, num);
264 virq = irq_find_mapping(NULL, hwirq);
266 cxl_unmap_irq(virq, cookie);
268 EXPORT_SYMBOL_GPL(cxl_unmap_afu_irq);
272 * Code here similar to afu_ioctl_start_work().
274 int cxl_start_context(struct cxl_context *ctx, u64 wed,
275 struct task_struct *task)
280 pr_devel("%s: pe: %i\n", __func__, ctx->pe);
282 mutex_lock(&ctx->status_mutex);
283 if (ctx->status == STARTED)
284 goto out; /* already started */
287 * Increment the mapped context count for adapter. This also checks
288 * if adapter_context_lock is taken.
290 rc = cxl_adapter_context_get(ctx->afu->adapter);
295 ctx->pid = get_task_pid(task, PIDTYPE_PID);
298 /* acquire a reference to the task's mm */
299 ctx->mm = get_task_mm(current);
301 /* ensure this mm_struct can't be freed */
302 cxl_context_mm_count_get(ctx);
305 /* decrement the use count from above */
307 /* make TLBIs for this context global */
308 mm_context_add_copro(ctx->mm);
313 * Increment driver use count. Enables global TLBIs for hash
314 * and callbacks to handle the segment table
318 /* See the comment in afu_ioctl_start_work() */
321 if ((rc = cxl_ops->attach_process(ctx, kernel, wed, 0))) {
324 cxl_adapter_context_put(ctx->afu->adapter);
327 cxl_context_mm_count_put(ctx);
329 mm_context_remove_copro(ctx->mm);
334 ctx->status = STARTED;
336 mutex_unlock(&ctx->status_mutex);
339 EXPORT_SYMBOL_GPL(cxl_start_context);
341 int cxl_process_element(struct cxl_context *ctx)
343 return ctx->external_pe;
345 EXPORT_SYMBOL_GPL(cxl_process_element);
347 /* Stop a context. Returns 0 on success, otherwise -Errno */
348 int cxl_stop_context(struct cxl_context *ctx)
350 return __detach_context(ctx);
352 EXPORT_SYMBOL_GPL(cxl_stop_context);
354 void cxl_set_master(struct cxl_context *ctx)
358 EXPORT_SYMBOL_GPL(cxl_set_master);
360 /* wrappers around afu_* file ops which are EXPORTED */
361 int cxl_fd_open(struct inode *inode, struct file *file)
363 return afu_open(inode, file);
365 EXPORT_SYMBOL_GPL(cxl_fd_open);
366 int cxl_fd_release(struct inode *inode, struct file *file)
368 return afu_release(inode, file);
370 EXPORT_SYMBOL_GPL(cxl_fd_release);
371 long cxl_fd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
373 return afu_ioctl(file, cmd, arg);
375 EXPORT_SYMBOL_GPL(cxl_fd_ioctl);
376 int cxl_fd_mmap(struct file *file, struct vm_area_struct *vm)
378 return afu_mmap(file, vm);
380 EXPORT_SYMBOL_GPL(cxl_fd_mmap);
381 __poll_t cxl_fd_poll(struct file *file, struct poll_table_struct *poll)
383 return afu_poll(file, poll);
385 EXPORT_SYMBOL_GPL(cxl_fd_poll);
386 ssize_t cxl_fd_read(struct file *file, char __user *buf, size_t count,
389 return afu_read(file, buf, count, off);
391 EXPORT_SYMBOL_GPL(cxl_fd_read);
393 #define PATCH_FOPS(NAME) if (!fops->NAME) fops->NAME = afu_fops.NAME
395 /* Get a struct file and fd for a context and attach the ops */
396 struct file *cxl_get_fd(struct cxl_context *ctx, struct file_operations *fops,
400 int rc, flags, fdtmp;
403 /* only allow one per context */
405 return ERR_PTR(-EEXIST);
407 flags = O_RDWR | O_CLOEXEC;
409 /* This code is similar to anon_inode_getfd() */
410 rc = get_unused_fd_flags(flags);
416 * Patch the file ops. Needs to be careful that this is rentrant safe.
423 PATCH_FOPS(unlocked_ioctl);
424 PATCH_FOPS(compat_ioctl);
426 } else /* use default ops */
427 fops = (struct file_operations *)&afu_fops;
429 name = kasprintf(GFP_KERNEL, "cxl:%d", ctx->pe);
430 file = cxl_getfile(name, fops, ctx, flags);
435 cxl_context_set_mapping(ctx, file->f_mapping);
440 put_unused_fd(fdtmp);
443 EXPORT_SYMBOL_GPL(cxl_get_fd);
445 struct cxl_context *cxl_fops_get_context(struct file *file)
447 return file->private_data;
449 EXPORT_SYMBOL_GPL(cxl_fops_get_context);
451 void cxl_set_driver_ops(struct cxl_context *ctx,
452 struct cxl_afu_driver_ops *ops)
454 WARN_ON(!ops->fetch_event || !ops->event_delivered);
455 atomic_set(&ctx->afu_driver_events, 0);
456 ctx->afu_driver_ops = ops;
458 EXPORT_SYMBOL_GPL(cxl_set_driver_ops);
460 void cxl_context_events_pending(struct cxl_context *ctx,
461 unsigned int new_events)
463 atomic_add(new_events, &ctx->afu_driver_events);
464 wake_up_all(&ctx->wq);
466 EXPORT_SYMBOL_GPL(cxl_context_events_pending);
468 int cxl_start_work(struct cxl_context *ctx,
469 struct cxl_ioctl_start_work *work)
473 /* code taken from afu_ioctl_start_work */
474 if (!(work->flags & CXL_START_WORK_NUM_IRQS))
475 work->num_interrupts = ctx->afu->pp_irqs;
476 else if ((work->num_interrupts < ctx->afu->pp_irqs) ||
477 (work->num_interrupts > ctx->afu->irqs_max)) {
481 rc = afu_register_irqs(ctx, work->num_interrupts);
485 rc = cxl_start_context(ctx, work->work_element_descriptor, current);
487 afu_release_irqs(ctx, ctx);
493 EXPORT_SYMBOL_GPL(cxl_start_work);
495 void __iomem *cxl_psa_map(struct cxl_context *ctx)
497 if (ctx->status != STARTED)
500 pr_devel("%s: psn_phys%llx size:%llx\n",
501 __func__, ctx->psn_phys, ctx->psn_size);
502 return ioremap(ctx->psn_phys, ctx->psn_size);
504 EXPORT_SYMBOL_GPL(cxl_psa_map);
506 void cxl_psa_unmap(void __iomem *addr)
510 EXPORT_SYMBOL_GPL(cxl_psa_unmap);
512 int cxl_afu_reset(struct cxl_context *ctx)
514 struct cxl_afu *afu = ctx->afu;
517 rc = cxl_ops->afu_reset(afu);
521 return cxl_ops->afu_check_and_enable(afu);
523 EXPORT_SYMBOL_GPL(cxl_afu_reset);
525 void cxl_perst_reloads_same_image(struct cxl_afu *afu,
526 bool perst_reloads_same_image)
528 afu->adapter->perst_same_image = perst_reloads_same_image;
530 EXPORT_SYMBOL_GPL(cxl_perst_reloads_same_image);
532 ssize_t cxl_read_adapter_vpd(struct pci_dev *dev, void *buf, size_t count)
534 struct cxl_afu *afu = cxl_pci_to_afu(dev);
538 return cxl_ops->read_adapter_vpd(afu->adapter, buf, count);
540 EXPORT_SYMBOL_GPL(cxl_read_adapter_vpd);