src/gallium/winsys/nouveau/drm/nouveau_drm_winsys.c

   1 #include <sys/stat.h>
   2 #include <unistd.h>
   3 #include <fcntl.h>
   4 #include "pipe/p_context.h"
   5 #include "pipe/p_state.h"
   6 #include "util/u_format.h"
   7 #include "util/u_memory.h"
   8 #include "util/u_inlines.h"
   9 #include "util/u_hash_table.h"
  10 #include "os/os_thread.h"
  11
  12 #include "nouveau_drm_public.h"
  13
  14 #include "nouveau/nouveau_winsys.h"
  15 #include "nouveau/nouveau_screen.h"
  16
  17 #include <nvif/class.h>
  18 #include <nvif/cl0080.h>
  19
  20 static struct util_hash_table *fd_tab = NULL;
  21
  22 static mtx_t nouveau_screen_mutex = _MTX_INITIALIZER_NP;
  23
  24 bool nouveau_drm_screen_unref(struct nouveau_screen *screen)
  25 {
  26         int ret;
  27         if (screen->refcount == -1)
  28                 return true;
  29
  30         pipe_mutex_lock(nouveau_screen_mutex);
  31         ret = --screen->refcount;
  32         assert(ret >= 0);
  33         if (ret == 0)
  34                 util_hash_table_remove(fd_tab, intptr_to_pointer(screen->drm->fd));
  35         pipe_mutex_unlock(nouveau_screen_mutex);
  36         return ret == 0;
  37 }
  38
  39 static unsigned hash_fd(void *key)
  40 {
  41     int fd = pointer_to_intptr(key);
  42     struct stat stat;
  43     fstat(fd, &stat);
  44
  45     return stat.st_dev ^ stat.st_ino ^ stat.st_rdev;
  46 }
  47
  48 static int compare_fd(void *key1, void *key2)
  49 {
  50     int fd1 = pointer_to_intptr(key1);
  51     int fd2 = pointer_to_intptr(key2);
  52     struct stat stat1, stat2;
  53     fstat(fd1, &stat1);
  54     fstat(fd2, &stat2);
  55
  56     return stat1.st_dev != stat2.st_dev ||
  57            stat1.st_ino != stat2.st_ino ||
  58            stat1.st_rdev != stat2.st_rdev;
  59 }
  60
  61 PUBLIC struct pipe_screen *
  62 nouveau_drm_screen_create(int fd)
  63 {
  64         struct nouveau_drm *drm = NULL;
  65         struct nouveau_device *dev = NULL;
  66         struct nouveau_screen *(*init)(struct nouveau_device *);
  67         struct nouveau_screen *screen = NULL;
  68         int ret, dupfd;
  69
  70         pipe_mutex_lock(nouveau_screen_mutex);
  71         if (!fd_tab) {
  72                 fd_tab = util_hash_table_create(hash_fd, compare_fd);
  73                 if (!fd_tab) {
  74                         pipe_mutex_unlock(nouveau_screen_mutex);
  75                         return NULL;
  76                 }
  77         }
  78
  79         screen = util_hash_table_get(fd_tab, intptr_to_pointer(fd));
  80         if (screen) {
  81                 screen->refcount++;
  82                 pipe_mutex_unlock(nouveau_screen_mutex);
  83                 return &screen->base;
  84         }
  85
  86         /* Since the screen re-use is based on the device node and not the fd,
  87          * create a copy of the fd to be owned by the device. Otherwise a
  88          * scenario could occur where two screens are created, and the first
  89          * one is shut down, along with the fd being closed. The second
  90          * (identical) screen would now have a reference to the closed fd. We
  91          * avoid this by duplicating the original fd. Note that
  92          * nouveau_device_wrap does not close the fd in case of a device
  93          * creation error.
  94          */
  95         dupfd = fcntl(fd, F_DUPFD_CLOEXEC, 3);
  96
  97         ret = nouveau_drm_new(dupfd, &drm);
  98         if (ret)
  99                 goto err;
 100
 101         ret = nouveau_device_new(&drm->client, NV_DEVICE,
 102                                  &(struct nv_device_v0) {
 103                                         .device = ~0ULL,
 104                                  }, sizeof(struct nv_device_v0), &dev);
 105         if (ret)
 106                 goto err;
 107
 108         switch (dev->chipset & ~0xf) {
 109         case 0x30:
 110         case 0x40:
 111         case 0x60:
 112                 init = nv30_screen_create;
 113                 break;
 114         case 0x50:
 115         case 0x80:
 116         case 0x90:
 117         case 0xa0:
 118                 init = nv50_screen_create;
 119                 break;
 120         case 0xc0:
 121         case 0xd0:
 122         case 0xe0:
 123         case 0xf0:
 124         case 0x100:
 125         case 0x110:
 126         case 0x120:
 127         case 0x130:
 128                 init = nvc0_screen_create;
 129                 break;
 130         default:
 131                 debug_printf("%s: unknown chipset nv%02x\n", __func__,
 132                              dev->chipset);
 133                 goto err;
 134         }
 135
 136         screen = init(dev);
 137         if (!screen || !screen->base.context_create)
 138                 goto err;
 139
 140         /* Use dupfd in hash table, to avoid errors if the original fd gets
 141          * closed by its owner. The hash key needs to live at least as long as
 142          * the screen.
 143          */
 144         util_hash_table_set(fd_tab, intptr_to_pointer(dupfd), screen);
 145         screen->refcount = 1;
 146         pipe_mutex_unlock(nouveau_screen_mutex);
 147         return &screen->base;
 148
 149 err:
 150         if (screen) {
 151                 screen->base.destroy(&screen->base);
 152         } else {
 153                 nouveau_device_del(&dev);
 154                 nouveau_drm_del(&drm);
 155                 close(dupfd);
 156         }
 157         pipe_mutex_unlock(nouveau_screen_mutex);
 158         return NULL;
 159 }