drivers/sbus/char/oradax.c

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This source file includes following definitions.
dax_attach
dax_detach
dax_devmap
dax_unlock_pages
dax_lock_page
dax_lock_pages
dax_ccb_wait
dax_close
dax_read
dax_write
dax_open
dax_hv_errno
dax_ccb_kill
dax_ccb_info
dax_prt_ccbs
dax_preprocess_usr_ccbs
dax_ccb_exec
   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
   4  */
   5 
   6 /*
   7  * Oracle Data Analytics Accelerator (DAX)
   8  *
   9  * DAX is a coprocessor which resides on the SPARC M7 (DAX1) and M8
  10  * (DAX2) processor chips, and has direct access to the CPU's L3
  11  * caches as well as physical memory. It can perform several
  12  * operations on data streams with various input and output formats.
  13  * The driver provides a transport mechanism only and has limited
  14  * knowledge of the various opcodes and data formats. A user space
  15  * library provides high level services and translates these into low
  16  * level commands which are then passed into the driver and
  17  * subsequently the hypervisor and the coprocessor.  The library is
  18  * the recommended way for applications to use the coprocessor, and
  19  * the driver interface is not intended for general use.
  20  *
  21  * See Documentation/sparc/oradax/oracle-dax.rst for more details.
  22  */
  23 
  24 #include <linux/uaccess.h>
  25 #include <linux/module.h>
  26 #include <linux/delay.h>
  27 #include <linux/cdev.h>
  28 #include <linux/slab.h>
  29 #include <linux/mm.h>
  30 
  31 #include <asm/hypervisor.h>
  32 #include <asm/mdesc.h>
  33 #include <asm/oradax.h>
  34 
  35 MODULE_LICENSE("GPL");
  36 MODULE_DESCRIPTION("Driver for Oracle Data Analytics Accelerator");
  37 
  38 #define DAX_DBG_FLG_BASIC       0x01
  39 #define DAX_DBG_FLG_STAT        0x02
  40 #define DAX_DBG_FLG_INFO        0x04
  41 #define DAX_DBG_FLG_ALL         0xff
  42 
  43 #define dax_err(fmt, ...)      pr_err("%s: " fmt "\n", __func__, ##__VA_ARGS__)
  44 #define dax_info(fmt, ...)     pr_info("%s: " fmt "\n", __func__, ##__VA_ARGS__)
  45 
  46 #define dax_dbg(fmt, ...)       do {                                    \
  47                                         if (dax_debug & DAX_DBG_FLG_BASIC)\
  48                                                 dax_info(fmt, ##__VA_ARGS__); \
  49                                 } while (0)
  50 #define dax_stat_dbg(fmt, ...)  do {                                    \
  51                                         if (dax_debug & DAX_DBG_FLG_STAT) \
  52                                                 dax_info(fmt, ##__VA_ARGS__); \
  53                                 } while (0)
  54 #define dax_info_dbg(fmt, ...)  do { \
  55                                         if (dax_debug & DAX_DBG_FLG_INFO) \
  56                                                 dax_info(fmt, ##__VA_ARGS__); \
  57                                 } while (0)
  58 
  59 #define DAX1_MINOR              1
  60 #define DAX1_MAJOR              1
  61 #define DAX2_MINOR              0
  62 #define DAX2_MAJOR              2
  63 
  64 #define DAX1_STR    "ORCL,sun4v-dax"
  65 #define DAX2_STR    "ORCL,sun4v-dax2"
  66 
  67 #define DAX_CA_ELEMS            (DAX_MMAP_LEN / sizeof(struct dax_cca))
  68 
  69 #define DAX_CCB_USEC            100
  70 #define DAX_CCB_RETRIES         10000
  71 
  72 /* stream types */
  73 enum {
  74         OUT,
  75         PRI,
  76         SEC,
  77         TBL,
  78         NUM_STREAM_TYPES
  79 };
  80 
  81 /* completion status */
  82 #define CCA_STAT_NOT_COMPLETED  0
  83 #define CCA_STAT_COMPLETED      1
  84 #define CCA_STAT_FAILED         2
  85 #define CCA_STAT_KILLED         3
  86 #define CCA_STAT_NOT_RUN        4
  87 #define CCA_STAT_PIPE_OUT       5
  88 #define CCA_STAT_PIPE_SRC       6
  89 #define CCA_STAT_PIPE_DST       7
  90 
  91 /* completion err */
  92 #define CCA_ERR_SUCCESS         0x0     /* no error */
  93 #define CCA_ERR_OVERFLOW        0x1     /* buffer overflow */
  94 #define CCA_ERR_DECODE          0x2     /* CCB decode error */
  95 #define CCA_ERR_PAGE_OVERFLOW   0x3     /* page overflow */
  96 #define CCA_ERR_KILLED          0x7     /* command was killed */
  97 #define CCA_ERR_TIMEOUT         0x8     /* Timeout */
  98 #define CCA_ERR_ADI             0x9     /* ADI error */
  99 #define CCA_ERR_DATA_FMT        0xA     /* data format error */
 100 #define CCA_ERR_OTHER_NO_RETRY  0xE     /* Other error, do not retry */
 101 #define CCA_ERR_OTHER_RETRY     0xF     /* Other error, retry */
 102 #define CCA_ERR_PARTIAL_SYMBOL  0x80    /* QP partial symbol warning */
 103 
 104 /* CCB address types */
 105 #define DAX_ADDR_TYPE_NONE      0
 106 #define DAX_ADDR_TYPE_VA_ALT    1       /* secondary context */
 107 #define DAX_ADDR_TYPE_RA        2       /* real address */
 108 #define DAX_ADDR_TYPE_VA        3       /* virtual address */
 109 
 110 /* dax_header_t opcode */
 111 #define DAX_OP_SYNC_NOP         0x0
 112 #define DAX_OP_EXTRACT          0x1
 113 #define DAX_OP_SCAN_VALUE       0x2
 114 #define DAX_OP_SCAN_RANGE       0x3
 115 #define DAX_OP_TRANSLATE        0x4
 116 #define DAX_OP_SELECT           0x5
 117 #define DAX_OP_INVERT           0x10    /* OR with translate, scan opcodes */
 118 
 119 struct dax_header {
 120         u32 ccb_version:4;      /* 31:28 CCB Version */
 121                                 /* 27:24 Sync Flags */
 122         u32 pipe:1;             /* Pipeline */
 123         u32 longccb:1;          /* Longccb. Set for scan with lu2, lu3, lu4. */
 124         u32 cond:1;             /* Conditional */
 125         u32 serial:1;           /* Serial */
 126         u32 opcode:8;           /* 23:16 Opcode */
 127                                 /* 15:0 Address Type. */
 128         u32 reserved:3;         /* 15:13 reserved */
 129         u32 table_addr_type:2;  /* 12:11 Huffman Table Address Type */
 130         u32 out_addr_type:3;    /* 10:8 Destination Address Type */
 131         u32 sec_addr_type:3;    /* 7:5 Secondary Source Address Type */
 132         u32 pri_addr_type:3;    /* 4:2 Primary Source Address Type */
 133         u32 cca_addr_type:2;    /* 1:0 Completion Address Type */
 134 };
 135 
 136 struct dax_control {
 137         u32 pri_fmt:4;          /* 31:28 Primary Input Format */
 138         u32 pri_elem_size:5;    /* 27:23 Primary Input Element Size(less1) */
 139         u32 pri_offset:3;       /* 22:20 Primary Input Starting Offset */
 140         u32 sec_encoding:1;     /* 19    Secondary Input Encoding */
 141                                 /*       (must be 0 for Select) */
 142         u32 sec_offset:3;       /* 18:16 Secondary Input Starting Offset */
 143         u32 sec_elem_size:2;    /* 15:14 Secondary Input Element Size */
 144                                 /*       (must be 0 for Select) */
 145         u32 out_fmt:2;          /* 13:12 Output Format */
 146         u32 out_elem_size:2;    /* 11:10 Output Element Size */
 147         u32 misc:10;            /* 9:0 Opcode specific info */
 148 };
 149 
 150 struct dax_data_access {
 151         u64 flow_ctrl:2;        /* 63:62 Flow Control Type */
 152         u64 pipe_target:2;      /* 61:60 Pipeline Target */
 153         u64 out_buf_size:20;    /* 59:40 Output Buffer Size */
 154                                 /*       (cachelines less 1) */
 155         u64 unused1:8;          /* 39:32 Reserved, Set to 0 */
 156         u64 out_alloc:5;        /* 31:27 Output Allocation */
 157         u64 unused2:1;          /* 26    Reserved */
 158         u64 pri_len_fmt:2;      /* 25:24 Input Length Format */
 159         u64 pri_len:24;         /* 23:0  Input Element/Byte/Bit Count */
 160                                 /*       (less 1) */
 161 };
 162 
 163 struct dax_ccb {
 164         struct dax_header hdr;  /* CCB Header */
 165         struct dax_control ctrl;/* Control Word */
 166         void *ca;               /* Completion Address */
 167         void *pri;              /* Primary Input Address */
 168         struct dax_data_access dac; /* Data Access Control */
 169         void *sec;              /* Secondary Input Address */
 170         u64 dword5;             /* depends on opcode */
 171         void *out;              /* Output Address */
 172         void *tbl;              /* Table Address or bitmap */
 173 };
 174 
 175 struct dax_cca {
 176         u8      status;         /* user may mwait on this address */
 177         u8      err;            /* user visible error notification */
 178         u8      rsvd[2];        /* reserved */
 179         u32     n_remaining;    /* for QP partial symbol warning */
 180         u32     output_sz;      /* output in bytes */
 181         u32     rsvd2;          /* reserved */
 182         u64     run_cycles;     /* run time in OCND2 cycles */
 183         u64     run_stats;      /* nothing reported in version 1.0 */
 184         u32     n_processed;    /* number input elements */
 185         u32     rsvd3[5];       /* reserved */
 186         u64     retval;         /* command return value */
 187         u64     rsvd4[8];       /* reserved */
 188 };
 189 
 190 /* per thread CCB context */
 191 struct dax_ctx {
 192         struct dax_ccb          *ccb_buf;
 193         u64                     ccb_buf_ra;     /* cached RA of ccb_buf  */
 194         struct dax_cca          *ca_buf;
 195         u64                     ca_buf_ra;      /* cached RA of ca_buf   */
 196         struct page             *pages[DAX_CA_ELEMS][NUM_STREAM_TYPES];
 197                                                 /* array of locked pages */
 198         struct task_struct      *owner;         /* thread that owns ctx  */
 199         struct task_struct      *client;        /* requesting thread     */
 200         union ccb_result        result;
 201         u32                     ccb_count;
 202         u32                     fail_count;
 203 };
 204 
 205 /* driver public entry points */
 206 static int dax_open(struct inode *inode, struct file *file);
 207 static ssize_t dax_read(struct file *filp, char __user *buf,
 208                         size_t count, loff_t *ppos);
 209 static ssize_t dax_write(struct file *filp, const char __user *buf,
 210                          size_t count, loff_t *ppos);
 211 static int dax_devmap(struct file *f, struct vm_area_struct *vma);
 212 static int dax_close(struct inode *i, struct file *f);
 213 
 214 static const struct file_operations dax_fops = {
 215         .owner  =       THIS_MODULE,
 216         .open   =       dax_open,
 217         .read   =       dax_read,
 218         .write  =       dax_write,
 219         .mmap   =       dax_devmap,
 220         .release =      dax_close,
 221 };
 222 
 223 static int dax_ccb_exec(struct dax_ctx *ctx, const char __user *buf,
 224                         size_t count, loff_t *ppos);
 225 static int dax_ccb_info(u64 ca, struct ccb_info_result *info);
 226 static int dax_ccb_kill(u64 ca, u16 *kill_res);
 227 
 228 static struct cdev c_dev;
 229 static struct class *cl;
 230 static dev_t first;
 231 
 232 static int max_ccb_version;
 233 static int dax_debug;
 234 module_param(dax_debug, int, 0644);
 235 MODULE_PARM_DESC(dax_debug, "Debug flags");
 236 
 237 static int __init dax_attach(void)
 238 {
 239         unsigned long dummy, hv_rv, major, minor, minor_requested, max_ccbs;
 240         struct mdesc_handle *hp = mdesc_grab();
 241         char *prop, *dax_name;
 242         bool found = false;
 243         int len, ret = 0;
 244         u64 pn;
 245 
 246         if (hp == NULL) {
 247                 dax_err("Unable to grab mdesc");
 248                 return -ENODEV;
 249         }
 250 
 251         mdesc_for_each_node_by_name(hp, pn, "virtual-device") {
 252                 prop = (char *)mdesc_get_property(hp, pn, "name", &len);
 253                 if (prop == NULL)
 254                         continue;
 255                 if (strncmp(prop, "dax", strlen("dax")))
 256                         continue;
 257                 dax_dbg("Found node 0x%llx = %s", pn, prop);
 258 
 259                 prop = (char *)mdesc_get_property(hp, pn, "compatible", &len);
 260                 if (prop == NULL)
 261                         continue;
 262                 dax_dbg("Found node 0x%llx = %s", pn, prop);
 263                 found = true;
 264                 break;
 265         }
 266 
 267         if (!found) {
 268                 dax_err("No DAX device found");
 269                 ret = -ENODEV;
 270                 goto done;
 271         }
 272 
 273         if (strncmp(prop, DAX2_STR, strlen(DAX2_STR)) == 0) {
 274                 dax_name = DAX_NAME "2";
 275                 major = DAX2_MAJOR;
 276                 minor_requested = DAX2_MINOR;
 277                 max_ccb_version = 1;
 278                 dax_dbg("MD indicates DAX2 coprocessor");
 279         } else if (strncmp(prop, DAX1_STR, strlen(DAX1_STR)) == 0) {
 280                 dax_name = DAX_NAME "1";
 281                 major = DAX1_MAJOR;
 282                 minor_requested = DAX1_MINOR;
 283                 max_ccb_version = 0;
 284                 dax_dbg("MD indicates DAX1 coprocessor");
 285         } else {
 286                 dax_err("Unknown dax type: %s", prop);
 287                 ret = -ENODEV;
 288                 goto done;
 289         }
 290 
 291         minor = minor_requested;
 292         dax_dbg("Registering DAX HV api with major %ld minor %ld", major,
 293                 minor);
 294         if (sun4v_hvapi_register(HV_GRP_DAX, major, &minor)) {
 295                 dax_err("hvapi_register failed");
 296                 ret = -ENODEV;
 297                 goto done;
 298         } else {
 299                 dax_dbg("Max minor supported by HV = %ld (major %ld)", minor,
 300                         major);
 301                 minor = min(minor, minor_requested);
 302                 dax_dbg("registered DAX major %ld minor %ld", major, minor);
 303         }
 304 
 305         /* submit a zero length ccb array to query coprocessor queue size */
 306         hv_rv = sun4v_ccb_submit(0, 0, HV_CCB_QUERY_CMD, 0, &max_ccbs, &dummy);
 307         if (hv_rv != 0) {
 308                 dax_err("get_hwqueue_size failed with status=%ld and max_ccbs=%ld",
 309                         hv_rv, max_ccbs);
 310                 ret = -ENODEV;
 311                 goto done;
 312         }
 313 
 314         if (max_ccbs != DAX_MAX_CCBS) {
 315                 dax_err("HV reports unsupported max_ccbs=%ld", max_ccbs);
 316                 ret = -ENODEV;
 317                 goto done;
 318         }
 319 
 320         if (alloc_chrdev_region(&first, 0, 1, DAX_NAME) < 0) {
 321                 dax_err("alloc_chrdev_region failed");
 322                 ret = -ENXIO;
 323                 goto done;
 324         }
 325 
 326         cl = class_create(THIS_MODULE, DAX_NAME);
 327         if (IS_ERR(cl)) {
 328                 dax_err("class_create failed");
 329                 ret = PTR_ERR(cl);
 330                 goto class_error;
 331         }
 332 
 333         if (device_create(cl, NULL, first, NULL, dax_name) == NULL) {
 334                 dax_err("device_create failed");
 335                 ret = -ENXIO;
 336                 goto device_error;
 337         }
 338 
 339         cdev_init(&c_dev, &dax_fops);
 340         if (cdev_add(&c_dev, first, 1) == -1) {
 341                 dax_err("cdev_add failed");
 342                 ret = -ENXIO;
 343                 goto cdev_error;
 344         }
 345 
 346         pr_info("Attached DAX module\n");
 347         goto done;
 348 
 349 cdev_error:
 350         device_destroy(cl, first);
 351 device_error:
 352         class_destroy(cl);
 353 class_error:
 354         unregister_chrdev_region(first, 1);
 355 done:
 356         mdesc_release(hp);
 357         return ret;
 358 }
 359 module_init(dax_attach);
 360 
 361 static void __exit dax_detach(void)
 362 {
 363         pr_info("Cleaning up DAX module\n");
 364         cdev_del(&c_dev);
 365         device_destroy(cl, first);
 366         class_destroy(cl);
 367         unregister_chrdev_region(first, 1);
 368 }
 369 module_exit(dax_detach);
 370 
 371 /* map completion area */
 372 static int dax_devmap(struct file *f, struct vm_area_struct *vma)
 373 {
 374         struct dax_ctx *ctx = (struct dax_ctx *)f->private_data;
 375         size_t len = vma->vm_end - vma->vm_start;
 376 
 377         dax_dbg("len=0x%lx, flags=0x%lx", len, vma->vm_flags);
 378 
 379         if (ctx->owner != current) {
 380                 dax_dbg("devmap called from wrong thread");
 381                 return -EINVAL;
 382         }
 383 
 384         if (len != DAX_MMAP_LEN) {
 385                 dax_dbg("len(%lu) != DAX_MMAP_LEN(%d)", len, DAX_MMAP_LEN);
 386                 return -EINVAL;
 387         }
 388 
 389         /* completion area is mapped read-only for user */
 390         if (vma->vm_flags & VM_WRITE)
 391                 return -EPERM;
 392         vma->vm_flags &= ~VM_MAYWRITE;
 393 
 394         if (remap_pfn_range(vma, vma->vm_start, ctx->ca_buf_ra >> PAGE_SHIFT,
 395                             len, vma->vm_page_prot))
 396                 return -EAGAIN;
 397 
 398         dax_dbg("mmapped completion area at uva 0x%lx", vma->vm_start);
 399         return 0;
 400 }
 401 
 402 /* Unlock user pages. Called during dequeue or device close */
 403 static void dax_unlock_pages(struct dax_ctx *ctx, int ccb_index, int nelem)
 404 {
 405         int i, j;
 406 
 407         for (i = ccb_index; i < ccb_index + nelem; i++) {
 408                 for (j = 0; j < NUM_STREAM_TYPES; j++) {
 409                         struct page *p = ctx->pages[i][j];
 410 
 411                         if (p) {
 412                                 dax_dbg("freeing page %p", p);
 413                                 if (j == OUT)
 414                                         set_page_dirty(p);
 415                                 put_page(p);
 416                                 ctx->pages[i][j] = NULL;
 417                         }
 418                 }
 419         }
 420 }
 421 
 422 static int dax_lock_page(void *va, struct page **p)
 423 {
 424         int ret;
 425 
 426         dax_dbg("uva %p", va);
 427 
 428         ret = get_user_pages_fast((unsigned long)va, 1, FOLL_WRITE, p);
 429         if (ret == 1) {
 430                 dax_dbg("locked page %p, for VA %p", *p, va);
 431                 return 0;
 432         }
 433 
 434         dax_dbg("get_user_pages failed, va=%p, ret=%d", va, ret);
 435         return -1;
 436 }
 437 
 438 static int dax_lock_pages(struct dax_ctx *ctx, int idx,
 439                           int nelem, u64 *err_va)
 440 {
 441         int i;
 442 
 443         for (i = 0; i < nelem; i++) {
 444                 struct dax_ccb *ccbp = &ctx->ccb_buf[i];
 445 
 446                 /*
 447                  * For each address in the CCB whose type is virtual,
 448                  * lock the page and change the type to virtual alternate
 449                  * context. On error, return the offending address in
 450                  * err_va.
 451                  */
 452                 if (ccbp->hdr.out_addr_type == DAX_ADDR_TYPE_VA) {
 453                         dax_dbg("output");
 454                         if (dax_lock_page(ccbp->out,
 455                                           &ctx->pages[i + idx][OUT]) != 0) {
 456                                 *err_va = (u64)ccbp->out;
 457                                 goto error;
 458                         }
 459                         ccbp->hdr.out_addr_type = DAX_ADDR_TYPE_VA_ALT;
 460                 }
 461 
 462                 if (ccbp->hdr.pri_addr_type == DAX_ADDR_TYPE_VA) {
 463                         dax_dbg("input");
 464                         if (dax_lock_page(ccbp->pri,
 465                                           &ctx->pages[i + idx][PRI]) != 0) {
 466                                 *err_va = (u64)ccbp->pri;
 467                                 goto error;
 468                         }
 469                         ccbp->hdr.pri_addr_type = DAX_ADDR_TYPE_VA_ALT;
 470                 }
 471 
 472                 if (ccbp->hdr.sec_addr_type == DAX_ADDR_TYPE_VA) {
 473                         dax_dbg("sec input");
 474                         if (dax_lock_page(ccbp->sec,
 475                                           &ctx->pages[i + idx][SEC]) != 0) {
 476                                 *err_va = (u64)ccbp->sec;
 477                                 goto error;
 478                         }
 479                         ccbp->hdr.sec_addr_type = DAX_ADDR_TYPE_VA_ALT;
 480                 }
 481 
 482                 if (ccbp->hdr.table_addr_type == DAX_ADDR_TYPE_VA) {
 483                         dax_dbg("tbl");
 484                         if (dax_lock_page(ccbp->tbl,
 485                                           &ctx->pages[i + idx][TBL]) != 0) {
 486                                 *err_va = (u64)ccbp->tbl;
 487                                 goto error;
 488                         }
 489                         ccbp->hdr.table_addr_type = DAX_ADDR_TYPE_VA_ALT;
 490                 }
 491 
 492                 /* skip over 2nd 64 bytes of long CCB */
 493                 if (ccbp->hdr.longccb)
 494                         i++;
 495         }
 496         return DAX_SUBMIT_OK;
 497 
 498 error:
 499         dax_unlock_pages(ctx, idx, nelem);
 500         return DAX_SUBMIT_ERR_NOACCESS;
 501 }
 502 
 503 static void dax_ccb_wait(struct dax_ctx *ctx, int idx)
 504 {
 505         int ret, nretries;
 506         u16 kill_res;
 507 
 508         dax_dbg("idx=%d", idx);
 509 
 510         for (nretries = 0; nretries < DAX_CCB_RETRIES; nretries++) {
 511                 if (ctx->ca_buf[idx].status == CCA_STAT_NOT_COMPLETED)
 512                         udelay(DAX_CCB_USEC);
 513                 else
 514                         return;
 515         }
 516         dax_dbg("ctx (%p): CCB[%d] timed out, wait usec=%d, retries=%d. Killing ccb",
 517                 (void *)ctx, idx, DAX_CCB_USEC, DAX_CCB_RETRIES);
 518 
 519         ret = dax_ccb_kill(ctx->ca_buf_ra + idx * sizeof(struct dax_cca),
 520                            &kill_res);
 521         dax_dbg("Kill CCB[%d] %s", idx, ret ? "failed" : "succeeded");
 522 }
 523 
 524 static int dax_close(struct inode *ino, struct file *f)
 525 {
 526         struct dax_ctx *ctx = (struct dax_ctx *)f->private_data;
 527         int i;
 528 
 529         f->private_data = NULL;
 530 
 531         for (i = 0; i < DAX_CA_ELEMS; i++) {
 532                 if (ctx->ca_buf[i].status == CCA_STAT_NOT_COMPLETED) {
 533                         dax_dbg("CCB[%d] not completed", i);
 534                         dax_ccb_wait(ctx, i);
 535                 }
 536                 dax_unlock_pages(ctx, i, 1);
 537         }
 538 
 539         kfree(ctx->ccb_buf);
 540         kfree(ctx->ca_buf);
 541         dax_stat_dbg("CCBs: %d good, %d bad", ctx->ccb_count, ctx->fail_count);
 542         kfree(ctx);
 543 
 544         return 0;
 545 }
 546 
 547 static ssize_t dax_read(struct file *f, char __user *buf,
 548                         size_t count, loff_t *ppos)
 549 {
 550         struct dax_ctx *ctx = f->private_data;
 551 
 552         if (ctx->client != current)
 553                 return -EUSERS;
 554 
 555         ctx->client = NULL;
 556 
 557         if (count != sizeof(union ccb_result))
 558                 return -EINVAL;
 559         if (copy_to_user(buf, &ctx->result, sizeof(union ccb_result)))
 560                 return -EFAULT;
 561         return count;
 562 }
 563 
 564 static ssize_t dax_write(struct file *f, const char __user *buf,
 565                          size_t count, loff_t *ppos)
 566 {
 567         struct dax_ctx *ctx = f->private_data;
 568         struct dax_command hdr;
 569         unsigned long ca;
 570         int i, idx, ret;
 571 
 572         if (ctx->client != NULL)
 573                 return -EINVAL;
 574 
 575         if (count == 0 || count > DAX_MAX_CCBS * sizeof(struct dax_ccb))
 576                 return -EINVAL;
 577 
 578         if (count % sizeof(struct dax_ccb) == 0)
 579                 return dax_ccb_exec(ctx, buf, count, ppos); /* CCB EXEC */
 580 
 581         if (count != sizeof(struct dax_command))
 582                 return -EINVAL;
 583 
 584         /* immediate command */
 585         if (ctx->owner != current)
 586                 return -EUSERS;
 587 
 588         if (copy_from_user(&hdr, buf, sizeof(hdr)))
 589                 return -EFAULT;
 590 
 591         ca = ctx->ca_buf_ra + hdr.ca_offset;
 592 
 593         switch (hdr.command) {
 594         case CCB_KILL:
 595                 if (hdr.ca_offset >= DAX_MMAP_LEN) {
 596                         dax_dbg("invalid ca_offset (%d) >= ca_buflen (%d)",
 597                                 hdr.ca_offset, DAX_MMAP_LEN);
 598                         return -EINVAL;
 599                 }
 600 
 601                 ret = dax_ccb_kill(ca, &ctx->result.kill.action);
 602                 if (ret != 0) {
 603                         dax_dbg("dax_ccb_kill failed (ret=%d)", ret);
 604                         return ret;
 605                 }
 606 
 607                 dax_info_dbg("killed (ca_offset %d)", hdr.ca_offset);
 608                 idx = hdr.ca_offset / sizeof(struct dax_cca);
 609                 ctx->ca_buf[idx].status = CCA_STAT_KILLED;
 610                 ctx->ca_buf[idx].err = CCA_ERR_KILLED;
 611                 ctx->client = current;
 612                 return count;
 613 
 614         case CCB_INFO:
 615                 if (hdr.ca_offset >= DAX_MMAP_LEN) {
 616                         dax_dbg("invalid ca_offset (%d) >= ca_buflen (%d)",
 617                                 hdr.ca_offset, DAX_MMAP_LEN);
 618                         return -EINVAL;
 619                 }
 620 
 621                 ret = dax_ccb_info(ca, &ctx->result.info);
 622                 if (ret != 0) {
 623                         dax_dbg("dax_ccb_info failed (ret=%d)", ret);
 624                         return ret;
 625                 }
 626 
 627                 dax_info_dbg("info succeeded on ca_offset %d", hdr.ca_offset);
 628                 ctx->client = current;
 629                 return count;
 630 
 631         case CCB_DEQUEUE:
 632                 for (i = 0; i < DAX_CA_ELEMS; i++) {
 633                         if (ctx->ca_buf[i].status !=
 634                             CCA_STAT_NOT_COMPLETED)
 635                                 dax_unlock_pages(ctx, i, 1);
 636                 }
 637                 return count;
 638 
 639         default:
 640                 return -EINVAL;
 641         }
 642 }
 643 
 644 static int dax_open(struct inode *inode, struct file *f)
 645 {
 646         struct dax_ctx *ctx = NULL;
 647         int i;
 648 
 649         ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
 650         if (ctx == NULL)
 651                 goto done;
 652 
 653         ctx->ccb_buf = kcalloc(DAX_MAX_CCBS, sizeof(struct dax_ccb),
 654                                GFP_KERNEL);
 655         if (ctx->ccb_buf == NULL)
 656                 goto done;
 657 
 658         ctx->ccb_buf_ra = virt_to_phys(ctx->ccb_buf);
 659         dax_dbg("ctx->ccb_buf=0x%p, ccb_buf_ra=0x%llx",
 660                 (void *)ctx->ccb_buf, ctx->ccb_buf_ra);
 661 
 662         /* allocate CCB completion area buffer */
 663         ctx->ca_buf = kzalloc(DAX_MMAP_LEN, GFP_KERNEL);
 664         if (ctx->ca_buf == NULL)
 665                 goto alloc_error;
 666         for (i = 0; i < DAX_CA_ELEMS; i++)
 667                 ctx->ca_buf[i].status = CCA_STAT_COMPLETED;
 668 
 669         ctx->ca_buf_ra = virt_to_phys(ctx->ca_buf);
 670         dax_dbg("ctx=0x%p, ctx->ca_buf=0x%p, ca_buf_ra=0x%llx",
 671                 (void *)ctx, (void *)ctx->ca_buf, ctx->ca_buf_ra);
 672 
 673         ctx->owner = current;
 674         f->private_data = ctx;
 675         return 0;
 676 
 677 alloc_error:
 678         kfree(ctx->ccb_buf);
 679 done:
 680         kfree(ctx);
 681         return -ENOMEM;
 682 }
 683 
 684 static char *dax_hv_errno(unsigned long hv_ret, int *ret)
 685 {
 686         switch (hv_ret) {
 687         case HV_EBADALIGN:
 688                 *ret = -EFAULT;
 689                 return "HV_EBADALIGN";
 690         case HV_ENORADDR:
 691                 *ret = -EFAULT;
 692                 return "HV_ENORADDR";
 693         case HV_EINVAL:
 694                 *ret = -EINVAL;
 695                 return "HV_EINVAL";
 696         case HV_EWOULDBLOCK:
 697                 *ret = -EAGAIN;
 698                 return "HV_EWOULDBLOCK";
 699         case HV_ENOACCESS:
 700                 *ret = -EPERM;
 701                 return "HV_ENOACCESS";
 702         default:
 703                 break;
 704         }
 705 
 706         *ret = -EIO;
 707         return "UNKNOWN";
 708 }
 709 
 710 static int dax_ccb_kill(u64 ca, u16 *kill_res)
 711 {
 712         unsigned long hv_ret;
 713         int count, ret = 0;
 714         char *err_str;
 715 
 716         for (count = 0; count < DAX_CCB_RETRIES; count++) {
 717                 dax_dbg("attempting kill on ca_ra 0x%llx", ca);
 718                 hv_ret = sun4v_ccb_kill(ca, kill_res);
 719 
 720                 if (hv_ret == HV_EOK) {
 721                         dax_info_dbg("HV_EOK (ca_ra 0x%llx): %d", ca,
 722                                      *kill_res);
 723                 } else {
 724                         err_str = dax_hv_errno(hv_ret, &ret);
 725                         dax_dbg("%s (ca_ra 0x%llx)", err_str, ca);
 726                 }
 727 
 728                 if (ret != -EAGAIN)
 729                         return ret;
 730                 dax_info_dbg("ccb_kill count = %d", count);
 731                 udelay(DAX_CCB_USEC);
 732         }
 733 
 734         return -EAGAIN;
 735 }
 736 
 737 static int dax_ccb_info(u64 ca, struct ccb_info_result *info)
 738 {
 739         unsigned long hv_ret;
 740         char *err_str;
 741         int ret = 0;
 742 
 743         dax_dbg("attempting info on ca_ra 0x%llx", ca);
 744         hv_ret = sun4v_ccb_info(ca, info);
 745 
 746         if (hv_ret == HV_EOK) {
 747                 dax_info_dbg("HV_EOK (ca_ra 0x%llx): %d", ca, info->state);
 748                 if (info->state == DAX_CCB_ENQUEUED) {
 749                         dax_info_dbg("dax_unit %d, queue_num %d, queue_pos %d",
 750                                      info->inst_num, info->q_num, info->q_pos);
 751                 }
 752         } else {
 753                 err_str = dax_hv_errno(hv_ret, &ret);
 754                 dax_dbg("%s (ca_ra 0x%llx)", err_str, ca);
 755         }
 756 
 757         return ret;
 758 }
 759 
 760 static void dax_prt_ccbs(struct dax_ccb *ccb, int nelem)
 761 {
 762         int i, j;
 763         u64 *ccbp;
 764 
 765         dax_dbg("ccb buffer:");
 766         for (i = 0; i < nelem; i++) {
 767                 ccbp = (u64 *)&ccb[i];
 768                 dax_dbg(" %sccb[%d]", ccb[i].hdr.longccb ? "long " : "",  i);
 769                 for (j = 0; j < 8; j++)
 770                         dax_dbg("\tccb[%d].dwords[%d]=0x%llx",
 771                                 i, j, *(ccbp + j));
 772         }
 773 }
 774 
 775 /*
 776  * Validates user CCB content.  Also sets completion address and address types
 777  * for all addresses contained in CCB.
 778  */
 779 static int dax_preprocess_usr_ccbs(struct dax_ctx *ctx, int idx, int nelem)
 780 {
 781         int i;
 782 
 783         /*
 784          * The user is not allowed to specify real address types in
 785          * the CCB header.  This must be enforced by the kernel before
 786          * submitting the CCBs to HV.  The only allowed values for all
 787          * address fields are VA or IMM
 788          */
 789         for (i = 0; i < nelem; i++) {
 790                 struct dax_ccb *ccbp = &ctx->ccb_buf[i];
 791                 unsigned long ca_offset;
 792 
 793                 if (ccbp->hdr.ccb_version > max_ccb_version)
 794                         return DAX_SUBMIT_ERR_CCB_INVAL;
 795 
 796                 switch (ccbp->hdr.opcode) {
 797                 case DAX_OP_SYNC_NOP:
 798                 case DAX_OP_EXTRACT:
 799                 case DAX_OP_SCAN_VALUE:
 800                 case DAX_OP_SCAN_RANGE:
 801                 case DAX_OP_TRANSLATE:
 802                 case DAX_OP_SCAN_VALUE | DAX_OP_INVERT:
 803                 case DAX_OP_SCAN_RANGE | DAX_OP_INVERT:
 804                 case DAX_OP_TRANSLATE | DAX_OP_INVERT:
 805                 case DAX_OP_SELECT:
 806                         break;
 807                 default:
 808                         return DAX_SUBMIT_ERR_CCB_INVAL;
 809                 }
 810 
 811                 if (ccbp->hdr.out_addr_type != DAX_ADDR_TYPE_VA &&
 812                     ccbp->hdr.out_addr_type != DAX_ADDR_TYPE_NONE) {
 813                         dax_dbg("invalid out_addr_type in user CCB[%d]", i);
 814                         return DAX_SUBMIT_ERR_CCB_INVAL;
 815                 }
 816 
 817                 if (ccbp->hdr.pri_addr_type != DAX_ADDR_TYPE_VA &&
 818                     ccbp->hdr.pri_addr_type != DAX_ADDR_TYPE_NONE) {
 819                         dax_dbg("invalid pri_addr_type in user CCB[%d]", i);
 820                         return DAX_SUBMIT_ERR_CCB_INVAL;
 821                 }
 822 
 823                 if (ccbp->hdr.sec_addr_type != DAX_ADDR_TYPE_VA &&
 824                     ccbp->hdr.sec_addr_type != DAX_ADDR_TYPE_NONE) {
 825                         dax_dbg("invalid sec_addr_type in user CCB[%d]", i);
 826                         return DAX_SUBMIT_ERR_CCB_INVAL;
 827                 }
 828 
 829                 if (ccbp->hdr.table_addr_type != DAX_ADDR_TYPE_VA &&
 830                     ccbp->hdr.table_addr_type != DAX_ADDR_TYPE_NONE) {
 831                         dax_dbg("invalid table_addr_type in user CCB[%d]", i);
 832                         return DAX_SUBMIT_ERR_CCB_INVAL;
 833                 }
 834 
 835                 /* set completion (real) address and address type */
 836                 ccbp->hdr.cca_addr_type = DAX_ADDR_TYPE_RA;
 837                 ca_offset = (idx + i) * sizeof(struct dax_cca);
 838                 ccbp->ca = (void *)ctx->ca_buf_ra + ca_offset;
 839                 memset(&ctx->ca_buf[idx + i], 0, sizeof(struct dax_cca));
 840 
 841                 dax_dbg("ccb[%d]=%p, ca_offset=0x%lx, compl RA=0x%llx",
 842                         i, ccbp, ca_offset, ctx->ca_buf_ra + ca_offset);
 843 
 844                 /* skip over 2nd 64 bytes of long CCB */
 845                 if (ccbp->hdr.longccb)
 846                         i++;
 847         }
 848 
 849         return DAX_SUBMIT_OK;
 850 }
 851 
 852 static int dax_ccb_exec(struct dax_ctx *ctx, const char __user *buf,
 853                         size_t count, loff_t *ppos)
 854 {
 855         unsigned long accepted_len, hv_rv;
 856         int i, idx, nccbs, naccepted;
 857 
 858         ctx->client = current;
 859         idx = *ppos;
 860         nccbs = count / sizeof(struct dax_ccb);
 861 
 862         if (ctx->owner != current) {
 863                 dax_dbg("wrong thread");
 864                 ctx->result.exec.status = DAX_SUBMIT_ERR_THR_INIT;
 865                 return 0;
 866         }
 867         dax_dbg("args: ccb_buf_len=%ld, idx=%d", count, idx);
 868 
 869         /* for given index and length, verify ca_buf range exists */
 870         if (idx < 0 || idx > (DAX_CA_ELEMS - nccbs)) {
 871                 ctx->result.exec.status = DAX_SUBMIT_ERR_NO_CA_AVAIL;
 872                 return 0;
 873         }
 874 
 875         /*
 876          * Copy CCBs into kernel buffer to prevent modification by the
 877          * user in between validation and submission.
 878          */
 879         if (copy_from_user(ctx->ccb_buf, buf, count)) {
 880                 dax_dbg("copyin of user CCB buffer failed");
 881                 ctx->result.exec.status = DAX_SUBMIT_ERR_CCB_ARR_MMU_MISS;
 882                 return 0;
 883         }
 884 
 885         /* check to see if ca_buf[idx] .. ca_buf[idx + nccbs] are available */
 886         for (i = idx; i < idx + nccbs; i++) {
 887                 if (ctx->ca_buf[i].status == CCA_STAT_NOT_COMPLETED) {
 888                         dax_dbg("CA range not available, dequeue needed");
 889                         ctx->result.exec.status = DAX_SUBMIT_ERR_NO_CA_AVAIL;
 890                         return 0;
 891                 }
 892         }
 893         dax_unlock_pages(ctx, idx, nccbs);
 894 
 895         ctx->result.exec.status = dax_preprocess_usr_ccbs(ctx, idx, nccbs);
 896         if (ctx->result.exec.status != DAX_SUBMIT_OK)
 897                 return 0;
 898 
 899         ctx->result.exec.status = dax_lock_pages(ctx, idx, nccbs,
 900                                                  &ctx->result.exec.status_data);
 901         if (ctx->result.exec.status != DAX_SUBMIT_OK)
 902                 return 0;
 903 
 904         if (dax_debug & DAX_DBG_FLG_BASIC)
 905                 dax_prt_ccbs(ctx->ccb_buf, nccbs);
 906 
 907         hv_rv = sun4v_ccb_submit(ctx->ccb_buf_ra, count,
 908                                  HV_CCB_QUERY_CMD | HV_CCB_VA_SECONDARY, 0,
 909                                  &accepted_len, &ctx->result.exec.status_data);
 910 
 911         switch (hv_rv) {
 912         case HV_EOK:
 913                 /*
 914                  * Hcall succeeded with no errors but the accepted
 915                  * length may be less than the requested length.  The
 916                  * only way the driver can resubmit the remainder is
 917                  * to wait for completion of the submitted CCBs since
 918                  * there is no way to guarantee the ordering semantics
 919                  * required by the client applications.  Therefore we
 920                  * let the user library deal with resubmissions.
 921                  */
 922                 ctx->result.exec.status = DAX_SUBMIT_OK;
 923                 break;
 924         case HV_EWOULDBLOCK:
 925                 /*
 926                  * This is a transient HV API error. The user library
 927                  * can retry.
 928                  */
 929                 dax_dbg("hcall returned HV_EWOULDBLOCK");
 930                 ctx->result.exec.status = DAX_SUBMIT_ERR_WOULDBLOCK;
 931                 break;
 932         case HV_ENOMAP:
 933                 /*
 934                  * HV was unable to translate a VA. The VA it could
 935                  * not translate is returned in the status_data param.
 936                  */
 937                 dax_dbg("hcall returned HV_ENOMAP");
 938                 ctx->result.exec.status = DAX_SUBMIT_ERR_NOMAP;
 939                 break;
 940         case HV_EINVAL:
 941                 /*
 942                  * This is the result of an invalid user CCB as HV is
 943                  * validating some of the user CCB fields.  Pass this
 944                  * error back to the user. There is no supporting info
 945                  * to isolate the invalid field.
 946                  */
 947                 dax_dbg("hcall returned HV_EINVAL");
 948                 ctx->result.exec.status = DAX_SUBMIT_ERR_CCB_INVAL;
 949                 break;
 950         case HV_ENOACCESS:
 951                 /*
 952                  * HV found a VA that did not have the appropriate
 953                  * permissions (such as the w bit). The VA in question
 954                  * is returned in status_data param.
 955                  */
 956                 dax_dbg("hcall returned HV_ENOACCESS");
 957                 ctx->result.exec.status = DAX_SUBMIT_ERR_NOACCESS;
 958                 break;
 959         case HV_EUNAVAILABLE:
 960                 /*
 961                  * The requested CCB operation could not be performed
 962                  * at this time. Return the specific unavailable code
 963                  * in the status_data field.
 964                  */
 965                 dax_dbg("hcall returned HV_EUNAVAILABLE");
 966                 ctx->result.exec.status = DAX_SUBMIT_ERR_UNAVAIL;
 967                 break;
 968         default:
 969                 ctx->result.exec.status = DAX_SUBMIT_ERR_INTERNAL;
 970                 dax_dbg("unknown hcall return value (%ld)", hv_rv);
 971                 break;
 972         }
 973 
 974         /* unlock pages associated with the unaccepted CCBs */
 975         naccepted = accepted_len / sizeof(struct dax_ccb);
 976         dax_unlock_pages(ctx, idx + naccepted, nccbs - naccepted);
 977 
 978         /* mark unaccepted CCBs as not completed */
 979         for (i = idx + naccepted; i < idx + nccbs; i++)
 980                 ctx->ca_buf[i].status = CCA_STAT_COMPLETED;
 981 
 982         ctx->ccb_count += naccepted;
 983         ctx->fail_count += nccbs - naccepted;
 984 
 985         dax_dbg("hcall rv=%ld, accepted_len=%ld, status_data=0x%llx, ret status=%d",
 986                 hv_rv, accepted_len, ctx->result.exec.status_data,
 987                 ctx->result.exec.status);
 988 
 989         if (count == accepted_len)
 990                 ctx->client = NULL; /* no read needed to complete protocol */
 991         return accepted_len;
 992 }
/* [<][>][^][v][top][bottom][index][help] */
root/drivers/sbus/char/oradax.c

DEFINITIONS
