drivers/misc/cxl/api.c

   1 /*
   2  * Copyright 2014 IBM Corp.
   3  *
   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.
   8  */
   9
  10 #include <linux/pci.h>
  11 #include <linux/slab.h>
  12 #include <linux/anon_inodes.h>
  13 #include <linux/file.h>
  14 #include <misc/cxl.h>
  15 #include <linux/fs.h>
  16
  17 #include "cxl.h"
  18
  19 struct cxl_context *cxl_dev_context_init(struct pci_dev *dev)
  20 {
  21         struct address_space *mapping;
  22         struct cxl_afu *afu;
  23         struct cxl_context  *ctx;
  24         int rc;
  25
  26         afu = cxl_pci_to_afu(dev);
  27
  28         get_device(&afu->dev);
  29         ctx = cxl_context_alloc();
  30         if (IS_ERR(ctx)) {
  31                 rc = PTR_ERR(ctx);
  32                 goto err_dev;
  33         }
  34
  35         ctx->kernelapi = true;
  36
  37         /*
  38          * Make our own address space since we won't have one from the
  39          * filesystem like the user api has, and even if we do associate a file
  40          * with this context we don't want to use the global anonymous inode's
  41          * address space as that can invalidate unrelated users:
  42          */
  43         mapping = kmalloc(sizeof(struct address_space), GFP_KERNEL);
  44         if (!mapping) {
  45                 rc = -ENOMEM;
  46                 goto err_ctx;
  47         }
  48         address_space_init_once(mapping);
  49
  50         /* Make it a slave context.  We can promote it later? */
  51         rc = cxl_context_init(ctx, afu, false, mapping);
  52         if (rc)
  53                 goto err_mapping;
  54
  55         cxl_assign_psn_space(ctx);
  56
  57         return ctx;
  58
  59 err_mapping:
  60         kfree(mapping);
  61 err_ctx:
  62         kfree(ctx);
  63 err_dev:
  64         put_device(&afu->dev);
  65         return ERR_PTR(rc);
  66 }
  67 EXPORT_SYMBOL_GPL(cxl_dev_context_init);
  68
  69 struct cxl_context *cxl_get_context(struct pci_dev *dev)
  70 {
  71         return dev->dev.archdata.cxl_ctx;
  72 }
  73 EXPORT_SYMBOL_GPL(cxl_get_context);
  74
  75 struct device *cxl_get_phys_dev(struct pci_dev *dev)
  76 {
  77         struct cxl_afu *afu;
  78
  79         afu = cxl_pci_to_afu(dev);
  80
  81         return afu->adapter->dev.parent;
  82 }
  83 EXPORT_SYMBOL_GPL(cxl_get_phys_dev);
  84
  85 int cxl_release_context(struct cxl_context *ctx)
  86 {
  87         if (ctx->status >= STARTED)
  88                 return -EBUSY;
  89
  90         put_device(&ctx->afu->dev);
  91
  92         cxl_context_free(ctx);
  93
  94         return 0;
  95 }
  96 EXPORT_SYMBOL_GPL(cxl_release_context);
  97
  98 int cxl_allocate_afu_irqs(struct cxl_context *ctx, int num)
  99 {
 100         if (num == 0)
 101                 num = ctx->afu->pp_irqs;
 102         return afu_allocate_irqs(ctx, num);
 103 }
 104 EXPORT_SYMBOL_GPL(cxl_allocate_afu_irqs);
 105
 106 void cxl_free_afu_irqs(struct cxl_context *ctx)
 107 {
 108         afu_irq_name_free(ctx);
 109         cxl_release_irq_ranges(&ctx->irqs, ctx->afu->adapter);
 110 }
 111 EXPORT_SYMBOL_GPL(cxl_free_afu_irqs);
 112
 113 static irq_hw_number_t cxl_find_afu_irq(struct cxl_context *ctx, int num)
 114 {
 115         __u16 range;
 116         int r;
 117
 118         WARN_ON(num == 0);
 119
 120         for (r = 0; r < CXL_IRQ_RANGES; r++) {
 121                 range = ctx->irqs.range[r];
 122                 if (num < range) {
 123                         return ctx->irqs.offset[r] + num;
 124                 }
 125                 num -= range;
 126         }
 127         return 0;
 128 }
 129
 130 int cxl_map_afu_irq(struct cxl_context *ctx, int num,
 131                     irq_handler_t handler, void *cookie, char *name)
 132 {
 133         irq_hw_number_t hwirq;
 134
 135         /*
 136          * Find interrupt we are to register.
 137          */
 138         hwirq = cxl_find_afu_irq(ctx, num);
 139         if (!hwirq)
 140                 return -ENOENT;
 141
 142         return cxl_map_irq(ctx->afu->adapter, hwirq, handler, cookie, name);
 143 }
 144 EXPORT_SYMBOL_GPL(cxl_map_afu_irq);
 145
 146 void cxl_unmap_afu_irq(struct cxl_context *ctx, int num, void *cookie)
 147 {
 148         irq_hw_number_t hwirq;
 149         unsigned int virq;
 150
 151         hwirq = cxl_find_afu_irq(ctx, num);
 152         if (!hwirq)
 153                 return;
 154
 155         virq = irq_find_mapping(NULL, hwirq);
 156         if (virq)
 157                 cxl_unmap_irq(virq, cookie);
 158 }
 159 EXPORT_SYMBOL_GPL(cxl_unmap_afu_irq);
 160
 161 /*
 162  * Start a context
 163  * Code here similar to afu_ioctl_start_work().
 164  */
 165 int cxl_start_context(struct cxl_context *ctx, u64 wed,
 166                       struct task_struct *task)
 167 {
 168         int rc = 0;
 169         bool kernel = true;
 170
 171         pr_devel("%s: pe: %i\n", __func__, ctx->pe);
 172
 173         mutex_lock(&ctx->status_mutex);
 174         if (ctx->status == STARTED)
 175                 goto out; /* already started */
 176
 177         if (task) {
 178                 ctx->pid = get_task_pid(task, PIDTYPE_PID);
 179                 get_pid(ctx->pid);
 180                 kernel = false;
 181         }
 182
 183         cxl_ctx_get();
 184
 185         if ((rc = cxl_attach_process(ctx, kernel, wed , 0))) {
 186                 put_pid(ctx->pid);
 187                 cxl_ctx_put();
 188                 goto out;
 189         }
 190
 191         ctx->status = STARTED;
 192 out:
 193         mutex_unlock(&ctx->status_mutex);
 194         return rc;
 195 }
 196 EXPORT_SYMBOL_GPL(cxl_start_context);
 197
 198 int cxl_process_element(struct cxl_context *ctx)
 199 {
 200         return ctx->pe;
 201 }
 202 EXPORT_SYMBOL_GPL(cxl_process_element);
 203
 204 /* Stop a context.  Returns 0 on success, otherwise -Errno */
 205 int cxl_stop_context(struct cxl_context *ctx)
 206 {
 207         return __detach_context(ctx);
 208 }
 209 EXPORT_SYMBOL_GPL(cxl_stop_context);
 210
 211 void cxl_set_master(struct cxl_context *ctx)
 212 {
 213         ctx->master = true;
 214         cxl_assign_psn_space(ctx);
 215 }
 216 EXPORT_SYMBOL_GPL(cxl_set_master);
 217
 218 /* wrappers around afu_* file ops which are EXPORTED */
 219 int cxl_fd_open(struct inode *inode, struct file *file)
 220 {
 221         return afu_open(inode, file);
 222 }
 223 EXPORT_SYMBOL_GPL(cxl_fd_open);
 224 int cxl_fd_release(struct inode *inode, struct file *file)
 225 {
 226         return afu_release(inode, file);
 227 }
 228 EXPORT_SYMBOL_GPL(cxl_fd_release);
 229 long cxl_fd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 230 {
 231         return afu_ioctl(file, cmd, arg);
 232 }
 233 EXPORT_SYMBOL_GPL(cxl_fd_ioctl);
 234 int cxl_fd_mmap(struct file *file, struct vm_area_struct *vm)
 235 {
 236         return afu_mmap(file, vm);
 237 }
 238 EXPORT_SYMBOL_GPL(cxl_fd_mmap);
 239 unsigned int cxl_fd_poll(struct file *file, struct poll_table_struct *poll)
 240 {
 241         return afu_poll(file, poll);
 242 }
 243 EXPORT_SYMBOL_GPL(cxl_fd_poll);
 244 ssize_t cxl_fd_read(struct file *file, char __user *buf, size_t count,
 245                         loff_t *off)
 246 {
 247         return afu_read(file, buf, count, off);
 248 }
 249 EXPORT_SYMBOL_GPL(cxl_fd_read);
 250
 251 #define PATCH_FOPS(NAME) if (!fops->NAME) fops->NAME = afu_fops.NAME
 252
 253 /* Get a struct file and fd for a context and attach the ops */
 254 struct file *cxl_get_fd(struct cxl_context *ctx, struct file_operations *fops,
 255                         int *fd)
 256 {
 257         struct file *file;
 258         int rc, flags, fdtmp;
 259
 260         flags = O_RDWR | O_CLOEXEC;
 261
 262         /* This code is similar to anon_inode_getfd() */
 263         rc = get_unused_fd_flags(flags);
 264         if (rc < 0)
 265                 return ERR_PTR(rc);
 266         fdtmp = rc;
 267
 268         /*
 269          * Patch the file ops.  Needs to be careful that this is rentrant safe.
 270          */
 271         if (fops) {
 272                 PATCH_FOPS(open);
 273                 PATCH_FOPS(poll);
 274                 PATCH_FOPS(read);
 275                 PATCH_FOPS(release);
 276                 PATCH_FOPS(unlocked_ioctl);
 277                 PATCH_FOPS(compat_ioctl);
 278                 PATCH_FOPS(mmap);
 279         } else /* use default ops */
 280                 fops = (struct file_operations *)&afu_fops;
 281
 282         file = anon_inode_getfile("cxl", fops, ctx, flags);
 283         if (IS_ERR(file))
 284                 goto err_fd;
 285
 286         file->f_mapping = ctx->mapping;
 287
 288         *fd = fdtmp;
 289         return file;
 290
 291 err_fd:
 292         put_unused_fd(fdtmp);
 293         return NULL;
 294 }
 295 EXPORT_SYMBOL_GPL(cxl_get_fd);
 296
 297 struct cxl_context *cxl_fops_get_context(struct file *file)
 298 {
 299         return file->private_data;
 300 }
 301 EXPORT_SYMBOL_GPL(cxl_fops_get_context);
 302
 303 int cxl_start_work(struct cxl_context *ctx,
 304                    struct cxl_ioctl_start_work *work)
 305 {
 306         int rc;
 307
 308         /* code taken from afu_ioctl_start_work */
 309         if (!(work->flags & CXL_START_WORK_NUM_IRQS))
 310                 work->num_interrupts = ctx->afu->pp_irqs;
 311         else if ((work->num_interrupts < ctx->afu->pp_irqs) ||
 312                  (work->num_interrupts > ctx->afu->irqs_max)) {
 313                 return -EINVAL;
 314         }
 315
 316         rc = afu_register_irqs(ctx, work->num_interrupts);
 317         if (rc)
 318                 return rc;
 319
 320         rc = cxl_start_context(ctx, work->work_element_descriptor, current);
 321         if (rc < 0) {
 322                 afu_release_irqs(ctx, ctx);
 323                 return rc;
 324         }
 325
 326         return 0;
 327 }
 328 EXPORT_SYMBOL_GPL(cxl_start_work);
 329
 330 void __iomem *cxl_psa_map(struct cxl_context *ctx)
 331 {
 332         struct cxl_afu *afu = ctx->afu;
 333         int rc;
 334
 335         rc = cxl_afu_check_and_enable(afu);
 336         if (rc)
 337                 return NULL;
 338
 339         pr_devel("%s: psn_phys%llx size:%llx\n",
 340                  __func__, afu->psn_phys, afu->adapter->ps_size);
 341         return ioremap(ctx->psn_phys, ctx->psn_size);
 342 }
 343 EXPORT_SYMBOL_GPL(cxl_psa_map);
 344
 345 void cxl_psa_unmap(void __iomem *addr)
 346 {
 347         iounmap(addr);
 348 }
 349 EXPORT_SYMBOL_GPL(cxl_psa_unmap);
 350
 351 int cxl_afu_reset(struct cxl_context *ctx)
 352 {
 353         struct cxl_afu *afu = ctx->afu;
 354         int rc;
 355
 356         rc = __cxl_afu_reset(afu);
 357         if (rc)
 358                 return rc;
 359
 360         return cxl_afu_check_and_enable(afu);
 361 }
 362 EXPORT_SYMBOL_GPL(cxl_afu_reset);
 363
 364 void cxl_perst_reloads_same_image(struct cxl_afu *afu,
 365                                   bool perst_reloads_same_image)
 366 {
 367         afu->adapter->perst_same_image = perst_reloads_same_image;
 368 }
 369 EXPORT_SYMBOL_GPL(cxl_perst_reloads_same_image);