diff options
Diffstat (limited to 'drivers/sbus/char/oradax.c')
-rw-r--r-- | drivers/sbus/char/oradax.c | 1004 |
1 files changed, 1004 insertions, 0 deletions
diff --git a/drivers/sbus/char/oradax.c b/drivers/sbus/char/oradax.c new file mode 100644 index 000000000..6516bc3cb --- /dev/null +++ b/drivers/sbus/char/oradax.c @@ -0,0 +1,1004 @@ +/* + * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved. + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +/* + * Oracle Data Analytics Accelerator (DAX) + * + * DAX is a coprocessor which resides on the SPARC M7 (DAX1) and M8 + * (DAX2) processor chips, and has direct access to the CPU's L3 + * caches as well as physical memory. It can perform several + * operations on data streams with various input and output formats. + * The driver provides a transport mechanism only and has limited + * knowledge of the various opcodes and data formats. A user space + * library provides high level services and translates these into low + * level commands which are then passed into the driver and + * subsequently the hypervisor and the coprocessor. The library is + * the recommended way for applications to use the coprocessor, and + * the driver interface is not intended for general use. + * + * See Documentation/sparc/oradax/oracle-dax.txt for more details. + */ + +#include <linux/uaccess.h> +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/cdev.h> +#include <linux/slab.h> +#include <linux/mm.h> + +#include <asm/hypervisor.h> +#include <asm/mdesc.h> +#include <asm/oradax.h> + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Driver for Oracle Data Analytics Accelerator"); + +#define DAX_DBG_FLG_BASIC 0x01 +#define DAX_DBG_FLG_STAT 0x02 +#define DAX_DBG_FLG_INFO 0x04 +#define DAX_DBG_FLG_ALL 0xff + +#define dax_err(fmt, ...) pr_err("%s: " fmt "\n", __func__, ##__VA_ARGS__) +#define dax_info(fmt, ...) pr_info("%s: " fmt "\n", __func__, ##__VA_ARGS__) + +#define dax_dbg(fmt, ...) do { \ + if (dax_debug & DAX_DBG_FLG_BASIC)\ + dax_info(fmt, ##__VA_ARGS__); \ + } while (0) +#define dax_stat_dbg(fmt, ...) do { \ + if (dax_debug & DAX_DBG_FLG_STAT) \ + dax_info(fmt, ##__VA_ARGS__); \ + } while (0) +#define dax_info_dbg(fmt, ...) do { \ + if (dax_debug & DAX_DBG_FLG_INFO) \ + dax_info(fmt, ##__VA_ARGS__); \ + } while (0) + +#define DAX1_MINOR 1 +#define DAX1_MAJOR 1 +#define DAX2_MINOR 0 +#define DAX2_MAJOR 2 + +#define DAX1_STR "ORCL,sun4v-dax" +#define DAX2_STR "ORCL,sun4v-dax2" + +#define DAX_CA_ELEMS (DAX_MMAP_LEN / sizeof(struct dax_cca)) + +#define DAX_CCB_USEC 100 +#define DAX_CCB_RETRIES 10000 + +/* stream types */ +enum { + OUT, + PRI, + SEC, + TBL, + NUM_STREAM_TYPES +}; + +/* completion status */ +#define CCA_STAT_NOT_COMPLETED 0 +#define CCA_STAT_COMPLETED 1 +#define CCA_STAT_FAILED 2 +#define CCA_STAT_KILLED 3 +#define CCA_STAT_NOT_RUN 4 +#define CCA_STAT_PIPE_OUT 5 +#define CCA_STAT_PIPE_SRC 6 +#define CCA_STAT_PIPE_DST 7 + +/* completion err */ +#define CCA_ERR_SUCCESS 0x0 /* no error */ +#define CCA_ERR_OVERFLOW 0x1 /* buffer overflow */ +#define CCA_ERR_DECODE 0x2 /* CCB decode error */ +#define CCA_ERR_PAGE_OVERFLOW 0x3 /* page overflow */ +#define CCA_ERR_KILLED 0x7 /* command was killed */ +#define CCA_ERR_TIMEOUT 0x8 /* Timeout */ +#define CCA_ERR_ADI 0x9 /* ADI error */ +#define CCA_ERR_DATA_FMT 0xA /* data format error */ +#define CCA_ERR_OTHER_NO_RETRY 0xE /* Other error, do not retry */ +#define CCA_ERR_OTHER_RETRY 0xF /* Other error, retry */ +#define CCA_ERR_PARTIAL_SYMBOL 0x80 /* QP partial symbol warning */ + +/* CCB address types */ +#define DAX_ADDR_TYPE_NONE 0 +#define DAX_ADDR_TYPE_VA_ALT 1 /* secondary context */ +#define DAX_ADDR_TYPE_RA 2 /* real address */ +#define DAX_ADDR_TYPE_VA 3 /* virtual address */ + +/* dax_header_t opcode */ +#define DAX_OP_SYNC_NOP 0x0 +#define DAX_OP_EXTRACT 0x1 +#define DAX_OP_SCAN_VALUE 0x2 +#define DAX_OP_SCAN_RANGE 0x3 +#define DAX_OP_TRANSLATE 0x4 +#define DAX_OP_SELECT 0x5 +#define DAX_OP_INVERT 0x10 /* OR with translate, scan opcodes */ + +struct dax_header { + u32 ccb_version:4; /* 31:28 CCB Version */ + /* 27:24 Sync Flags */ + u32 pipe:1; /* Pipeline */ + u32 longccb:1; /* Longccb. Set for scan with lu2, lu3, lu4. */ + u32 cond:1; /* Conditional */ + u32 serial:1; /* Serial */ + u32 opcode:8; /* 23:16 Opcode */ + /* 15:0 Address Type. */ + u32 reserved:3; /* 15:13 reserved */ + u32 table_addr_type:2; /* 12:11 Huffman Table Address Type */ + u32 out_addr_type:3; /* 10:8 Destination Address Type */ + u32 sec_addr_type:3; /* 7:5 Secondary Source Address Type */ + u32 pri_addr_type:3; /* 4:2 Primary Source Address Type */ + u32 cca_addr_type:2; /* 1:0 Completion Address Type */ +}; + +struct dax_control { + u32 pri_fmt:4; /* 31:28 Primary Input Format */ + u32 pri_elem_size:5; /* 27:23 Primary Input Element Size(less1) */ + u32 pri_offset:3; /* 22:20 Primary Input Starting Offset */ + u32 sec_encoding:1; /* 19 Secondary Input Encoding */ + /* (must be 0 for Select) */ + u32 sec_offset:3; /* 18:16 Secondary Input Starting Offset */ + u32 sec_elem_size:2; /* 15:14 Secondary Input Element Size */ + /* (must be 0 for Select) */ + u32 out_fmt:2; /* 13:12 Output Format */ + u32 out_elem_size:2; /* 11:10 Output Element Size */ + u32 misc:10; /* 9:0 Opcode specific info */ +}; + +struct dax_data_access { + u64 flow_ctrl:2; /* 63:62 Flow Control Type */ + u64 pipe_target:2; /* 61:60 Pipeline Target */ + u64 out_buf_size:20; /* 59:40 Output Buffer Size */ + /* (cachelines less 1) */ + u64 unused1:8; /* 39:32 Reserved, Set to 0 */ + u64 out_alloc:5; /* 31:27 Output Allocation */ + u64 unused2:1; /* 26 Reserved */ + u64 pri_len_fmt:2; /* 25:24 Input Length Format */ + u64 pri_len:24; /* 23:0 Input Element/Byte/Bit Count */ + /* (less 1) */ +}; + +struct dax_ccb { + struct dax_header hdr; /* CCB Header */ + struct dax_control ctrl;/* Control Word */ + void *ca; /* Completion Address */ + void *pri; /* Primary Input Address */ + struct dax_data_access dac; /* Data Access Control */ + void *sec; /* Secondary Input Address */ + u64 dword5; /* depends on opcode */ + void *out; /* Output Address */ + void *tbl; /* Table Address or bitmap */ +}; + +struct dax_cca { + u8 status; /* user may mwait on this address */ + u8 err; /* user visible error notification */ + u8 rsvd[2]; /* reserved */ + u32 n_remaining; /* for QP partial symbol warning */ + u32 output_sz; /* output in bytes */ + u32 rsvd2; /* reserved */ + u64 run_cycles; /* run time in OCND2 cycles */ + u64 run_stats; /* nothing reported in version 1.0 */ + u32 n_processed; /* number input elements */ + u32 rsvd3[5]; /* reserved */ + u64 retval; /* command return value */ + u64 rsvd4[8]; /* reserved */ +}; + +/* per thread CCB context */ +struct dax_ctx { + struct dax_ccb *ccb_buf; + u64 ccb_buf_ra; /* cached RA of ccb_buf */ + struct dax_cca *ca_buf; + u64 ca_buf_ra; /* cached RA of ca_buf */ + struct page *pages[DAX_CA_ELEMS][NUM_STREAM_TYPES]; + /* array of locked pages */ + struct task_struct *owner; /* thread that owns ctx */ + struct task_struct *client; /* requesting thread */ + union ccb_result result; + u32 ccb_count; + u32 fail_count; +}; + +/* driver public entry points */ +static int dax_open(struct inode *inode, struct file *file); +static ssize_t dax_read(struct file *filp, char __user *buf, + size_t count, loff_t *ppos); +static ssize_t dax_write(struct file *filp, const char __user *buf, + size_t count, loff_t *ppos); +static int dax_devmap(struct file *f, struct vm_area_struct *vma); +static int dax_close(struct inode *i, struct file *f); + +static const struct file_operations dax_fops = { + .owner = THIS_MODULE, + .open = dax_open, + .read = dax_read, + .write = dax_write, + .mmap = dax_devmap, + .release = dax_close, +}; + +static int dax_ccb_exec(struct dax_ctx *ctx, const char __user *buf, + size_t count, loff_t *ppos); +static int dax_ccb_info(u64 ca, struct ccb_info_result *info); +static int dax_ccb_kill(u64 ca, u16 *kill_res); + +static struct cdev c_dev; +static struct class *cl; +static dev_t first; + +static int max_ccb_version; +static int dax_debug; +module_param(dax_debug, int, 0644); +MODULE_PARM_DESC(dax_debug, "Debug flags"); + +static int __init dax_attach(void) +{ + unsigned long dummy, hv_rv, major, minor, minor_requested, max_ccbs; + struct mdesc_handle *hp = mdesc_grab(); + char *prop, *dax_name; + bool found = false; + int len, ret = 0; + u64 pn; + + if (hp == NULL) { + dax_err("Unable to grab mdesc"); + return -ENODEV; + } + + mdesc_for_each_node_by_name(hp, pn, "virtual-device") { + prop = (char *)mdesc_get_property(hp, pn, "name", &len); + if (prop == NULL) + continue; + if (strncmp(prop, "dax", strlen("dax"))) + continue; + dax_dbg("Found node 0x%llx = %s", pn, prop); + + prop = (char *)mdesc_get_property(hp, pn, "compatible", &len); + if (prop == NULL) + continue; + dax_dbg("Found node 0x%llx = %s", pn, prop); + found = true; + break; + } + + if (!found) { + dax_err("No DAX device found"); + ret = -ENODEV; + goto done; + } + + if (strncmp(prop, DAX2_STR, strlen(DAX2_STR)) == 0) { + dax_name = DAX_NAME "2"; + major = DAX2_MAJOR; + minor_requested = DAX2_MINOR; + max_ccb_version = 1; + dax_dbg("MD indicates DAX2 coprocessor"); + } else if (strncmp(prop, DAX1_STR, strlen(DAX1_STR)) == 0) { + dax_name = DAX_NAME "1"; + major = DAX1_MAJOR; + minor_requested = DAX1_MINOR; + max_ccb_version = 0; + dax_dbg("MD indicates DAX1 coprocessor"); + } else { + dax_err("Unknown dax type: %s", prop); + ret = -ENODEV; + goto done; + } + + minor = minor_requested; + dax_dbg("Registering DAX HV api with major %ld minor %ld", major, + minor); + if (sun4v_hvapi_register(HV_GRP_DAX, major, &minor)) { + dax_err("hvapi_register failed"); + ret = -ENODEV; + goto done; + } else { + dax_dbg("Max minor supported by HV = %ld (major %ld)", minor, + major); + minor = min(minor, minor_requested); + dax_dbg("registered DAX major %ld minor %ld", major, minor); + } + + /* submit a zero length ccb array to query coprocessor queue size */ + hv_rv = sun4v_ccb_submit(0, 0, HV_CCB_QUERY_CMD, 0, &max_ccbs, &dummy); + if (hv_rv != 0) { + dax_err("get_hwqueue_size failed with status=%ld and max_ccbs=%ld", + hv_rv, max_ccbs); + ret = -ENODEV; + goto done; + } + + if (max_ccbs != DAX_MAX_CCBS) { + dax_err("HV reports unsupported max_ccbs=%ld", max_ccbs); + ret = -ENODEV; + goto done; + } + + if (alloc_chrdev_region(&first, 0, 1, DAX_NAME) < 0) { + dax_err("alloc_chrdev_region failed"); + ret = -ENXIO; + goto done; + } + + cl = class_create(THIS_MODULE, DAX_NAME); + if (IS_ERR(cl)) { + dax_err("class_create failed"); + ret = PTR_ERR(cl); + goto class_error; + } + + if (device_create(cl, NULL, first, NULL, dax_name) == NULL) { + dax_err("device_create failed"); + ret = -ENXIO; + goto device_error; + } + + cdev_init(&c_dev, &dax_fops); + if (cdev_add(&c_dev, first, 1) == -1) { + dax_err("cdev_add failed"); + ret = -ENXIO; + goto cdev_error; + } + + pr_info("Attached DAX module\n"); + goto done; + +cdev_error: + device_destroy(cl, first); +device_error: + class_destroy(cl); +class_error: + unregister_chrdev_region(first, 1); +done: + mdesc_release(hp); + return ret; +} +module_init(dax_attach); + +static void __exit dax_detach(void) +{ + pr_info("Cleaning up DAX module\n"); + cdev_del(&c_dev); + device_destroy(cl, first); + class_destroy(cl); + unregister_chrdev_region(first, 1); +} +module_exit(dax_detach); + +/* map completion area */ +static int dax_devmap(struct file *f, struct vm_area_struct *vma) +{ + struct dax_ctx *ctx = (struct dax_ctx *)f->private_data; + size_t len = vma->vm_end - vma->vm_start; + + dax_dbg("len=0x%lx, flags=0x%lx", len, vma->vm_flags); + + if (ctx->owner != current) { + dax_dbg("devmap called from wrong thread"); + return -EINVAL; + } + + if (len != DAX_MMAP_LEN) { + dax_dbg("len(%lu) != DAX_MMAP_LEN(%d)", len, DAX_MMAP_LEN); + return -EINVAL; + } + + /* completion area is mapped read-only for user */ + if (vma->vm_flags & VM_WRITE) + return -EPERM; + vma->vm_flags &= ~VM_MAYWRITE; + + if (remap_pfn_range(vma, vma->vm_start, ctx->ca_buf_ra >> PAGE_SHIFT, + len, vma->vm_page_prot)) + return -EAGAIN; + + dax_dbg("mmapped completion area at uva 0x%lx", vma->vm_start); + return 0; +} + +/* Unlock user pages. Called during dequeue or device close */ +static void dax_unlock_pages(struct dax_ctx *ctx, int ccb_index, int nelem) +{ + int i, j; + + for (i = ccb_index; i < ccb_index + nelem; i++) { + for (j = 0; j < NUM_STREAM_TYPES; j++) { + struct page *p = ctx->pages[i][j]; + + if (p) { + dax_dbg("freeing page %p", p); + if (j == OUT) + set_page_dirty(p); + put_page(p); + ctx->pages[i][j] = NULL; + } + } + } +} + +static int dax_lock_page(void *va, struct page **p) +{ + int ret; + + dax_dbg("uva %p", va); + + ret = get_user_pages_fast((unsigned long)va, 1, 1, p); + if (ret == 1) { + dax_dbg("locked page %p, for VA %p", *p, va); + return 0; + } + + dax_dbg("get_user_pages failed, va=%p, ret=%d", va, ret); + return -1; +} + +static int dax_lock_pages(struct dax_ctx *ctx, int idx, + int nelem, u64 *err_va) +{ + int i; + + for (i = 0; i < nelem; i++) { + struct dax_ccb *ccbp = &ctx->ccb_buf[i]; + + /* + * For each address in the CCB whose type is virtual, + * lock the page and change the type to virtual alternate + * context. On error, return the offending address in + * err_va. + */ + if (ccbp->hdr.out_addr_type == DAX_ADDR_TYPE_VA) { + dax_dbg("output"); + if (dax_lock_page(ccbp->out, + &ctx->pages[i + idx][OUT]) != 0) { + *err_va = (u64)ccbp->out; + goto error; + } + ccbp->hdr.out_addr_type = DAX_ADDR_TYPE_VA_ALT; + } + + if (ccbp->hdr.pri_addr_type == DAX_ADDR_TYPE_VA) { + dax_dbg("input"); + if (dax_lock_page(ccbp->pri, + &ctx->pages[i + idx][PRI]) != 0) { + *err_va = (u64)ccbp->pri; + goto error; + } + ccbp->hdr.pri_addr_type = DAX_ADDR_TYPE_VA_ALT; + } + + if (ccbp->hdr.sec_addr_type == DAX_ADDR_TYPE_VA) { + dax_dbg("sec input"); + if (dax_lock_page(ccbp->sec, + &ctx->pages[i + idx][SEC]) != 0) { + *err_va = (u64)ccbp->sec; + goto error; + } + ccbp->hdr.sec_addr_type = DAX_ADDR_TYPE_VA_ALT; + } + + if (ccbp->hdr.table_addr_type == DAX_ADDR_TYPE_VA) { + dax_dbg("tbl"); + if (dax_lock_page(ccbp->tbl, + &ctx->pages[i + idx][TBL]) != 0) { + *err_va = (u64)ccbp->tbl; + goto error; + } + ccbp->hdr.table_addr_type = DAX_ADDR_TYPE_VA_ALT; + } + + /* skip over 2nd 64 bytes of long CCB */ + if (ccbp->hdr.longccb) + i++; + } + return DAX_SUBMIT_OK; + +error: + dax_unlock_pages(ctx, idx, nelem); + return DAX_SUBMIT_ERR_NOACCESS; +} + +static void dax_ccb_wait(struct dax_ctx *ctx, int idx) +{ + int ret, nretries; + u16 kill_res; + + dax_dbg("idx=%d", idx); + + for (nretries = 0; nretries < DAX_CCB_RETRIES; nretries++) { + if (ctx->ca_buf[idx].status == CCA_STAT_NOT_COMPLETED) + udelay(DAX_CCB_USEC); + else + return; + } + dax_dbg("ctx (%p): CCB[%d] timed out, wait usec=%d, retries=%d. Killing ccb", + (void *)ctx, idx, DAX_CCB_USEC, DAX_CCB_RETRIES); + + ret = dax_ccb_kill(ctx->ca_buf_ra + idx * sizeof(struct dax_cca), + &kill_res); + dax_dbg("Kill CCB[%d] %s", idx, ret ? "failed" : "succeeded"); +} + +static int dax_close(struct inode *ino, struct file *f) +{ + struct dax_ctx *ctx = (struct dax_ctx *)f->private_data; + int i; + + f->private_data = NULL; + + for (i = 0; i < DAX_CA_ELEMS; i++) { + if (ctx->ca_buf[i].status == CCA_STAT_NOT_COMPLETED) { + dax_dbg("CCB[%d] not completed", i); + dax_ccb_wait(ctx, i); + } + dax_unlock_pages(ctx, i, 1); + } + + kfree(ctx->ccb_buf); + kfree(ctx->ca_buf); + dax_stat_dbg("CCBs: %d good, %d bad", ctx->ccb_count, ctx->fail_count); + kfree(ctx); + + return 0; +} + +static ssize_t dax_read(struct file *f, char __user *buf, + size_t count, loff_t *ppos) +{ + struct dax_ctx *ctx = f->private_data; + + if (ctx->client != current) + return -EUSERS; + + ctx->client = NULL; + + if (count != sizeof(union ccb_result)) + return -EINVAL; + if (copy_to_user(buf, &ctx->result, sizeof(union ccb_result))) + return -EFAULT; + return count; +} + +static ssize_t dax_write(struct file *f, const char __user *buf, + size_t count, loff_t *ppos) +{ + struct dax_ctx *ctx = f->private_data; + struct dax_command hdr; + unsigned long ca; + int i, idx, ret; + + if (ctx->client != NULL) + return -EINVAL; + + if (count == 0 || count > DAX_MAX_CCBS * sizeof(struct dax_ccb)) + return -EINVAL; + + if (count % sizeof(struct dax_ccb) == 0) + return dax_ccb_exec(ctx, buf, count, ppos); /* CCB EXEC */ + + if (count != sizeof(struct dax_command)) + return -EINVAL; + + /* immediate command */ + if (ctx->owner != current) + return -EUSERS; + + if (copy_from_user(&hdr, buf, sizeof(hdr))) + return -EFAULT; + + ca = ctx->ca_buf_ra + hdr.ca_offset; + + switch (hdr.command) { + case CCB_KILL: + if (hdr.ca_offset >= DAX_MMAP_LEN) { + dax_dbg("invalid ca_offset (%d) >= ca_buflen (%d)", + hdr.ca_offset, DAX_MMAP_LEN); + return -EINVAL; + } + + ret = dax_ccb_kill(ca, &ctx->result.kill.action); + if (ret != 0) { + dax_dbg("dax_ccb_kill failed (ret=%d)", ret); + return ret; + } + + dax_info_dbg("killed (ca_offset %d)", hdr.ca_offset); + idx = hdr.ca_offset / sizeof(struct dax_cca); + ctx->ca_buf[idx].status = CCA_STAT_KILLED; + ctx->ca_buf[idx].err = CCA_ERR_KILLED; + ctx->client = current; + return count; + + case CCB_INFO: + if (hdr.ca_offset >= DAX_MMAP_LEN) { + dax_dbg("invalid ca_offset (%d) >= ca_buflen (%d)", + hdr.ca_offset, DAX_MMAP_LEN); + return -EINVAL; + } + + ret = dax_ccb_info(ca, &ctx->result.info); + if (ret != 0) { + dax_dbg("dax_ccb_info failed (ret=%d)", ret); + return ret; + } + + dax_info_dbg("info succeeded on ca_offset %d", hdr.ca_offset); + ctx->client = current; + return count; + + case CCB_DEQUEUE: + for (i = 0; i < DAX_CA_ELEMS; i++) { + if (ctx->ca_buf[i].status != + CCA_STAT_NOT_COMPLETED) + dax_unlock_pages(ctx, i, 1); + } + return count; + + default: + return -EINVAL; + } +} + +static int dax_open(struct inode *inode, struct file *f) +{ + struct dax_ctx *ctx = NULL; + int i; + + ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); + if (ctx == NULL) + goto done; + + ctx->ccb_buf = kcalloc(DAX_MAX_CCBS, sizeof(struct dax_ccb), + GFP_KERNEL); + if (ctx->ccb_buf == NULL) + goto done; + + ctx->ccb_buf_ra = virt_to_phys(ctx->ccb_buf); + dax_dbg("ctx->ccb_buf=0x%p, ccb_buf_ra=0x%llx", + (void *)ctx->ccb_buf, ctx->ccb_buf_ra); + + /* allocate CCB completion area buffer */ + ctx->ca_buf = kzalloc(DAX_MMAP_LEN, GFP_KERNEL); + if (ctx->ca_buf == NULL) + goto alloc_error; + for (i = 0; i < DAX_CA_ELEMS; i++) + ctx->ca_buf[i].status = CCA_STAT_COMPLETED; + + ctx->ca_buf_ra = virt_to_phys(ctx->ca_buf); + dax_dbg("ctx=0x%p, ctx->ca_buf=0x%p, ca_buf_ra=0x%llx", + (void *)ctx, (void *)ctx->ca_buf, ctx->ca_buf_ra); + + ctx->owner = current; + f->private_data = ctx; + return 0; + +alloc_error: + kfree(ctx->ccb_buf); +done: + kfree(ctx); + return -ENOMEM; +} + +static char *dax_hv_errno(unsigned long hv_ret, int *ret) +{ + switch (hv_ret) { + case HV_EBADALIGN: + *ret = -EFAULT; + return "HV_EBADALIGN"; + case HV_ENORADDR: + *ret = -EFAULT; + return "HV_ENORADDR"; + case HV_EINVAL: + *ret = -EINVAL; + return "HV_EINVAL"; + case HV_EWOULDBLOCK: + *ret = -EAGAIN; + return "HV_EWOULDBLOCK"; + case HV_ENOACCESS: + *ret = -EPERM; + return "HV_ENOACCESS"; + default: + break; + } + + *ret = -EIO; + return "UNKNOWN"; +} + +static int dax_ccb_kill(u64 ca, u16 *kill_res) +{ + unsigned long hv_ret; + int count, ret = 0; + char *err_str; + + for (count = 0; count < DAX_CCB_RETRIES; count++) { + dax_dbg("attempting kill on ca_ra 0x%llx", ca); + hv_ret = sun4v_ccb_kill(ca, kill_res); + + if (hv_ret == HV_EOK) { + dax_info_dbg("HV_EOK (ca_ra 0x%llx): %d", ca, + *kill_res); + } else { + err_str = dax_hv_errno(hv_ret, &ret); + dax_dbg("%s (ca_ra 0x%llx)", err_str, ca); + } + + if (ret != -EAGAIN) + return ret; + dax_info_dbg("ccb_kill count = %d", count); + udelay(DAX_CCB_USEC); + } + + return -EAGAIN; +} + +static int dax_ccb_info(u64 ca, struct ccb_info_result *info) +{ + unsigned long hv_ret; + char *err_str; + int ret = 0; + + dax_dbg("attempting info on ca_ra 0x%llx", ca); + hv_ret = sun4v_ccb_info(ca, info); + + if (hv_ret == HV_EOK) { + dax_info_dbg("HV_EOK (ca_ra 0x%llx): %d", ca, info->state); + if (info->state == DAX_CCB_ENQUEUED) { + dax_info_dbg("dax_unit %d, queue_num %d, queue_pos %d", + info->inst_num, info->q_num, info->q_pos); + } + } else { + err_str = dax_hv_errno(hv_ret, &ret); + dax_dbg("%s (ca_ra 0x%llx)", err_str, ca); + } + + return ret; +} + +static void dax_prt_ccbs(struct dax_ccb *ccb, int nelem) +{ + int i, j; + u64 *ccbp; + + dax_dbg("ccb buffer:"); + for (i = 0; i < nelem; i++) { + ccbp = (u64 *)&ccb[i]; + dax_dbg(" %sccb[%d]", ccb[i].hdr.longccb ? "long " : "", i); + for (j = 0; j < 8; j++) + dax_dbg("\tccb[%d].dwords[%d]=0x%llx", + i, j, *(ccbp + j)); + } +} + +/* + * Validates user CCB content. Also sets completion address and address types + * for all addresses contained in CCB. + */ +static int dax_preprocess_usr_ccbs(struct dax_ctx *ctx, int idx, int nelem) +{ + int i; + + /* + * The user is not allowed to specify real address types in + * the CCB header. This must be enforced by the kernel before + * submitting the CCBs to HV. The only allowed values for all + * address fields are VA or IMM + */ + for (i = 0; i < nelem; i++) { + struct dax_ccb *ccbp = &ctx->ccb_buf[i]; + unsigned long ca_offset; + + if (ccbp->hdr.ccb_version > max_ccb_version) + return DAX_SUBMIT_ERR_CCB_INVAL; + + switch (ccbp->hdr.opcode) { + case DAX_OP_SYNC_NOP: + case DAX_OP_EXTRACT: + case DAX_OP_SCAN_VALUE: + case DAX_OP_SCAN_RANGE: + case DAX_OP_TRANSLATE: + case DAX_OP_SCAN_VALUE | DAX_OP_INVERT: + case DAX_OP_SCAN_RANGE | DAX_OP_INVERT: + case DAX_OP_TRANSLATE | DAX_OP_INVERT: + case DAX_OP_SELECT: + break; + default: + return DAX_SUBMIT_ERR_CCB_INVAL; + } + + if (ccbp->hdr.out_addr_type != DAX_ADDR_TYPE_VA && + ccbp->hdr.out_addr_type != DAX_ADDR_TYPE_NONE) { + dax_dbg("invalid out_addr_type in user CCB[%d]", i); + return DAX_SUBMIT_ERR_CCB_INVAL; + } + + if (ccbp->hdr.pri_addr_type != DAX_ADDR_TYPE_VA && + ccbp->hdr.pri_addr_type != DAX_ADDR_TYPE_NONE) { + dax_dbg("invalid pri_addr_type in user CCB[%d]", i); + return DAX_SUBMIT_ERR_CCB_INVAL; + } + + if (ccbp->hdr.sec_addr_type != DAX_ADDR_TYPE_VA && + ccbp->hdr.sec_addr_type != DAX_ADDR_TYPE_NONE) { + dax_dbg("invalid sec_addr_type in user CCB[%d]", i); + return DAX_SUBMIT_ERR_CCB_INVAL; + } + + if (ccbp->hdr.table_addr_type != DAX_ADDR_TYPE_VA && + ccbp->hdr.table_addr_type != DAX_ADDR_TYPE_NONE) { + dax_dbg("invalid table_addr_type in user CCB[%d]", i); + return DAX_SUBMIT_ERR_CCB_INVAL; + } + + /* set completion (real) address and address type */ + ccbp->hdr.cca_addr_type = DAX_ADDR_TYPE_RA; + ca_offset = (idx + i) * sizeof(struct dax_cca); + ccbp->ca = (void *)ctx->ca_buf_ra + ca_offset; + memset(&ctx->ca_buf[idx + i], 0, sizeof(struct dax_cca)); + + dax_dbg("ccb[%d]=%p, ca_offset=0x%lx, compl RA=0x%llx", + i, ccbp, ca_offset, ctx->ca_buf_ra + ca_offset); + + /* skip over 2nd 64 bytes of long CCB */ + if (ccbp->hdr.longccb) + i++; + } + + return DAX_SUBMIT_OK; +} + +static int dax_ccb_exec(struct dax_ctx *ctx, const char __user *buf, + size_t count, loff_t *ppos) +{ + unsigned long accepted_len, hv_rv; + int i, idx, nccbs, naccepted; + + ctx->client = current; + idx = *ppos; + nccbs = count / sizeof(struct dax_ccb); + + if (ctx->owner != current) { + dax_dbg("wrong thread"); + ctx->result.exec.status = DAX_SUBMIT_ERR_THR_INIT; + return 0; + } + dax_dbg("args: ccb_buf_len=%ld, idx=%d", count, idx); + + /* for given index and length, verify ca_buf range exists */ + if (idx < 0 || idx > (DAX_CA_ELEMS - nccbs)) { + ctx->result.exec.status = DAX_SUBMIT_ERR_NO_CA_AVAIL; + return 0; + } + + /* + * Copy CCBs into kernel buffer to prevent modification by the + * user in between validation and submission. + */ + if (copy_from_user(ctx->ccb_buf, buf, count)) { + dax_dbg("copyin of user CCB buffer failed"); + ctx->result.exec.status = DAX_SUBMIT_ERR_CCB_ARR_MMU_MISS; + return 0; + } + + /* check to see if ca_buf[idx] .. ca_buf[idx + nccbs] are available */ + for (i = idx; i < idx + nccbs; i++) { + if (ctx->ca_buf[i].status == CCA_STAT_NOT_COMPLETED) { + dax_dbg("CA range not available, dequeue needed"); + ctx->result.exec.status = DAX_SUBMIT_ERR_NO_CA_AVAIL; + return 0; + } + } + dax_unlock_pages(ctx, idx, nccbs); + + ctx->result.exec.status = dax_preprocess_usr_ccbs(ctx, idx, nccbs); + if (ctx->result.exec.status != DAX_SUBMIT_OK) + return 0; + + ctx->result.exec.status = dax_lock_pages(ctx, idx, nccbs, + &ctx->result.exec.status_data); + if (ctx->result.exec.status != DAX_SUBMIT_OK) + return 0; + + if (dax_debug & DAX_DBG_FLG_BASIC) + dax_prt_ccbs(ctx->ccb_buf, nccbs); + + hv_rv = sun4v_ccb_submit(ctx->ccb_buf_ra, count, + HV_CCB_QUERY_CMD | HV_CCB_VA_SECONDARY, 0, + &accepted_len, &ctx->result.exec.status_data); + + switch (hv_rv) { + case HV_EOK: + /* + * Hcall succeeded with no errors but the accepted + * length may be less than the requested length. The + * only way the driver can resubmit the remainder is + * to wait for completion of the submitted CCBs since + * there is no way to guarantee the ordering semantics + * required by the client applications. Therefore we + * let the user library deal with resubmissions. + */ + ctx->result.exec.status = DAX_SUBMIT_OK; + break; + case HV_EWOULDBLOCK: + /* + * This is a transient HV API error. The user library + * can retry. + */ + dax_dbg("hcall returned HV_EWOULDBLOCK"); + ctx->result.exec.status = DAX_SUBMIT_ERR_WOULDBLOCK; + break; + case HV_ENOMAP: + /* + * HV was unable to translate a VA. The VA it could + * not translate is returned in the status_data param. + */ + dax_dbg("hcall returned HV_ENOMAP"); + ctx->result.exec.status = DAX_SUBMIT_ERR_NOMAP; + break; + case HV_EINVAL: + /* + * This is the result of an invalid user CCB as HV is + * validating some of the user CCB fields. Pass this + * error back to the user. There is no supporting info + * to isolate the invalid field. + */ + dax_dbg("hcall returned HV_EINVAL"); + ctx->result.exec.status = DAX_SUBMIT_ERR_CCB_INVAL; + break; + case HV_ENOACCESS: + /* + * HV found a VA that did not have the appropriate + * permissions (such as the w bit). The VA in question + * is returned in status_data param. + */ + dax_dbg("hcall returned HV_ENOACCESS"); + ctx->result.exec.status = DAX_SUBMIT_ERR_NOACCESS; + break; + case HV_EUNAVAILABLE: + /* + * The requested CCB operation could not be performed + * at this time. Return the specific unavailable code + * in the status_data field. + */ + dax_dbg("hcall returned HV_EUNAVAILABLE"); + ctx->result.exec.status = DAX_SUBMIT_ERR_UNAVAIL; + break; + default: + ctx->result.exec.status = DAX_SUBMIT_ERR_INTERNAL; + dax_dbg("unknown hcall return value (%ld)", hv_rv); + break; + } + + /* unlock pages associated with the unaccepted CCBs */ + naccepted = accepted_len / sizeof(struct dax_ccb); + dax_unlock_pages(ctx, idx + naccepted, nccbs - naccepted); + + /* mark unaccepted CCBs as not completed */ + for (i = idx + naccepted; i < idx + nccbs; i++) + ctx->ca_buf[i].status = CCA_STAT_COMPLETED; + + ctx->ccb_count += naccepted; + ctx->fail_count += nccbs - naccepted; + + dax_dbg("hcall rv=%ld, accepted_len=%ld, status_data=0x%llx, ret status=%d", + hv_rv, accepted_len, ctx->result.exec.status_data, + ctx->result.exec.status); + + if (count == accepted_len) + ctx->client = NULL; /* no read needed to complete protocol */ + return accepted_len; +} |