drivers/s390/char/sclp_pci.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * PCI I/O adapter configuration related functions.
   4  *
   5  * Copyright IBM Corp. 2016
   6  */
   7 #define KMSG_COMPONENT "sclp_cmd"
   8 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
   9
  10 #include <linux/completion.h>
  11 #include <linux/export.h>
  12 #include <linux/mutex.h>
  13 #include <linux/errno.h>
  14 #include <linux/slab.h>
  15 #include <linux/init.h>
  16 #include <linux/err.h>
  17
  18 #include <asm/sclp.h>
  19
  20 #include "sclp.h"
  21
  22 #define SCLP_CMDW_CONFIGURE_PCI                 0x001a0001
  23 #define SCLP_CMDW_DECONFIGURE_PCI               0x001b0001
  24
  25 #define SCLP_ATYPE_PCI                          2
  26
  27 #define SCLP_ERRNOTIFY_AQ_REPAIR                1
  28 #define SCLP_ERRNOTIFY_AQ_INFO_LOG              2
  29
  30 static DEFINE_MUTEX(sclp_pci_mutex);
  31 static struct sclp_register sclp_pci_event = {
  32         .send_mask = EVTYP_ERRNOTIFY_MASK,
  33 };
  34
  35 struct err_notify_evbuf {
  36         struct evbuf_header header;
  37         u8 action;
  38         u8 atype;
  39         u32 fh;
  40         u32 fid;
  41         u8 data[0];
  42 } __packed;
  43
  44 struct err_notify_sccb {
  45         struct sccb_header header;
  46         struct err_notify_evbuf evbuf;
  47 } __packed;
  48
  49 struct pci_cfg_sccb {
  50         struct sccb_header header;
  51         u8 atype;               /* adapter type */
  52         u8 reserved1;
  53         u16 reserved2;
  54         u32 aid;                /* adapter identifier */
  55 } __packed;
  56
  57 static int do_pci_configure(sclp_cmdw_t cmd, u32 fid)
  58 {
  59         struct pci_cfg_sccb *sccb;
  60         int rc;
  61
  62         if (!SCLP_HAS_PCI_RECONFIG)
  63                 return -EOPNOTSUPP;
  64
  65         sccb = (struct pci_cfg_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
  66         if (!sccb)
  67                 return -ENOMEM;
  68
  69         sccb->header.length = PAGE_SIZE;
  70         sccb->atype = SCLP_ATYPE_PCI;
  71         sccb->aid = fid;
  72         rc = sclp_sync_request(cmd, sccb);
  73         if (rc)
  74                 goto out;
  75         switch (sccb->header.response_code) {
  76         case 0x0020:
  77         case 0x0120:
  78                 break;
  79         default:
  80                 pr_warn("configure PCI I/O adapter failed: cmd=0x%08x  response=0x%04x\n",
  81                         cmd, sccb->header.response_code);
  82                 rc = -EIO;
  83                 break;
  84         }
  85 out:
  86         free_page((unsigned long) sccb);
  87         return rc;
  88 }
  89
  90 int sclp_pci_configure(u32 fid)
  91 {
  92         return do_pci_configure(SCLP_CMDW_CONFIGURE_PCI, fid);
  93 }
  94 EXPORT_SYMBOL(sclp_pci_configure);
  95
  96 int sclp_pci_deconfigure(u32 fid)
  97 {
  98         return do_pci_configure(SCLP_CMDW_DECONFIGURE_PCI, fid);
  99 }
 100 EXPORT_SYMBOL(sclp_pci_deconfigure);
 101
 102 static void sclp_pci_callback(struct sclp_req *req, void *data)
 103 {
 104         struct completion *completion = data;
 105
 106         complete(completion);
 107 }
 108
 109 static int sclp_pci_check_report(struct zpci_report_error_header *report)
 110 {
 111         if (report->version != 1)
 112                 return -EINVAL;
 113
 114         if (report->action != SCLP_ERRNOTIFY_AQ_REPAIR &&
 115             report->action != SCLP_ERRNOTIFY_AQ_INFO_LOG)
 116                 return -EINVAL;
 117
 118         if (report->length > (PAGE_SIZE - sizeof(struct err_notify_sccb)))
 119                 return -EINVAL;
 120
 121         return 0;
 122 }
 123
 124 int sclp_pci_report(struct zpci_report_error_header *report, u32 fh, u32 fid)
 125 {
 126         DECLARE_COMPLETION_ONSTACK(completion);
 127         struct err_notify_sccb *sccb;
 128         struct sclp_req req;
 129         int ret;
 130
 131         ret = sclp_pci_check_report(report);
 132         if (ret)
 133                 return ret;
 134
 135         mutex_lock(&sclp_pci_mutex);
 136         ret = sclp_register(&sclp_pci_event);
 137         if (ret)
 138                 goto out_unlock;
 139
 140         if (!(sclp_pci_event.sclp_receive_mask & EVTYP_ERRNOTIFY_MASK)) {
 141                 ret = -EOPNOTSUPP;
 142                 goto out_unregister;
 143         }
 144
 145         sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
 146         if (!sccb) {
 147                 ret = -ENOMEM;
 148                 goto out_unregister;
 149         }
 150
 151         memset(&req, 0, sizeof(req));
 152         req.callback_data = &completion;
 153         req.callback = sclp_pci_callback;
 154         req.command = SCLP_CMDW_WRITE_EVENT_DATA;
 155         req.status = SCLP_REQ_FILLED;
 156         req.sccb = sccb;
 157
 158         sccb->evbuf.header.length = sizeof(sccb->evbuf) + report->length;
 159         sccb->evbuf.header.type = EVTYP_ERRNOTIFY;
 160         sccb->header.length = sizeof(sccb->header) + sccb->evbuf.header.length;
 161
 162         sccb->evbuf.action = report->action;
 163         sccb->evbuf.atype = SCLP_ATYPE_PCI;
 164         sccb->evbuf.fh = fh;
 165         sccb->evbuf.fid = fid;
 166
 167         memcpy(sccb->evbuf.data, report->data, report->length);
 168
 169         ret = sclp_add_request(&req);
 170         if (ret)
 171                 goto out_free_req;
 172
 173         wait_for_completion(&completion);
 174         if (req.status != SCLP_REQ_DONE) {
 175                 pr_warn("request failed (status=0x%02x)\n",
 176                         req.status);
 177                 ret = -EIO;
 178                 goto out_free_req;
 179         }
 180
 181         if (sccb->header.response_code != 0x0020) {
 182                 pr_warn("request failed with response code 0x%x\n",
 183                         sccb->header.response_code);
 184                 ret = -EIO;
 185         }
 186
 187 out_free_req:
 188         free_page((unsigned long) sccb);
 189 out_unregister:
 190         sclp_unregister(&sclp_pci_event);
 191 out_unlock:
 192         mutex_unlock(&sclp_pci_mutex);
 193         return ret;
 194 }