patch-2.3.31 linux/drivers/char/drm/tdfx_drv.c

Next file: linux/drivers/char/drm/tdfx_drv.h
Previous file: linux/drivers/char/drm/tdfx_context.c
Back to the patch index
Back to the overall index

diff -u --recursive --new-file v2.3.30/linux/drivers/char/drm/tdfx_drv.c linux/drivers/char/drm/tdfx_drv.c
@@ -0,0 +1,601 @@
+/* tdfx.c -- tdfx driver -*- linux-c -*-
+ * Created: Thu Oct  7 10:38:32 1999 by faith@precisioninsight.com
+ * Revised: Tue Oct 12 08:51:35 1999 by faith@precisioninsight.com
+ *
+ * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * PRECISION INSIGHT AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ * 
+ * $PI$
+ * $XFree86$
+ *
+ */
+
+#define EXPORT_SYMTAB
+#include <linux/config.h>
+#include "drmP.h"
+#include "tdfx_drv.h"
+EXPORT_SYMBOL(tdfx_init);
+EXPORT_SYMBOL(tdfx_cleanup);
+
+#define TDFX_NAME	 "tdfx"
+#define TDFX_DESC	 "tdfx"
+#define TDFX_DATE	 "19991009"
+#define TDFX_MAJOR	 0
+#define TDFX_MINOR	 0
+#define TDFX_PATCHLEVEL  1
+
+static drm_device_t	      tdfx_device;
+drm_ctx_t	              tdfx_res_ctx;
+
+static struct file_operations tdfx_fops = {
+	open:	 tdfx_open,
+	flush:	 drm_flush,
+	release: tdfx_release,
+	ioctl:	 tdfx_ioctl,
+	mmap:	 drm_mmap,
+	read:	 drm_read,
+	fasync:	 drm_fasync,
+};
+
+static struct miscdevice      tdfx_misc = {
+	minor: MISC_DYNAMIC_MINOR,
+	name:  TDFX_NAME,
+	fops:  &tdfx_fops,
+};
+
+static drm_ioctl_desc_t	      tdfx_ioctls[] = {
+	[DRM_IOCTL_NR(DRM_IOCTL_VERSION)]    = { tdfx_version,	  0, 0 },
+	[DRM_IOCTL_NR(DRM_IOCTL_GET_UNIQUE)] = { drm_getunique,	  0, 0 },
+	[DRM_IOCTL_NR(DRM_IOCTL_GET_MAGIC)]  = { drm_getmagic,	  0, 0 },
+	[DRM_IOCTL_NR(DRM_IOCTL_IRQ_BUSID)]  = { drm_irq_busid,	  0, 1 },
+
+	[DRM_IOCTL_NR(DRM_IOCTL_SET_UNIQUE)] = { drm_setunique,	  1, 1 },
+	[DRM_IOCTL_NR(DRM_IOCTL_BLOCK)]	     = { drm_block,	  1, 1 },
+	[DRM_IOCTL_NR(DRM_IOCTL_UNBLOCK)]    = { drm_unblock,	  1, 1 },
+	[DRM_IOCTL_NR(DRM_IOCTL_AUTH_MAGIC)] = { drm_authmagic,	  1, 1 },
+	[DRM_IOCTL_NR(DRM_IOCTL_ADD_MAP)]    = { drm_addmap,	  1, 1 },
+	
+	[DRM_IOCTL_NR(DRM_IOCTL_ADD_CTX)]    = { tdfx_addctx,	  1, 1 },
+	[DRM_IOCTL_NR(DRM_IOCTL_RM_CTX)]     = { tdfx_rmctx,	  1, 1 },
+	[DRM_IOCTL_NR(DRM_IOCTL_MOD_CTX)]    = { tdfx_modctx,	  1, 1 },
+	[DRM_IOCTL_NR(DRM_IOCTL_GET_CTX)]    = { tdfx_getctx,	  1, 0 },
+	[DRM_IOCTL_NR(DRM_IOCTL_SWITCH_CTX)] = { tdfx_switchctx,  1, 1 },
+	[DRM_IOCTL_NR(DRM_IOCTL_NEW_CTX)]    = { tdfx_newctx,	  1, 1 },
+	[DRM_IOCTL_NR(DRM_IOCTL_RES_CTX)]    = { tdfx_resctx,	  1, 0 },
+	[DRM_IOCTL_NR(DRM_IOCTL_ADD_DRAW)]   = { drm_adddraw,	  1, 1 },
+	[DRM_IOCTL_NR(DRM_IOCTL_RM_DRAW)]    = { drm_rmdraw,	  1, 1 },
+	[DRM_IOCTL_NR(DRM_IOCTL_LOCK)]	     = { tdfx_lock,	  1, 0 },
+	[DRM_IOCTL_NR(DRM_IOCTL_UNLOCK)]     = { tdfx_unlock,	  1, 0 },
+	[DRM_IOCTL_NR(DRM_IOCTL_FINISH)]     = { drm_finish,	  1, 0 },
+};
+#define TDFX_IOCTL_COUNT DRM_ARRAY_SIZE(tdfx_ioctls)
+
+static char		      *tdfx = NULL;
+
+MODULE_AUTHOR("Precision Insight, Inc., Cedar Park, Texas.");
+MODULE_DESCRIPTION("tdfx");
+MODULE_PARM(tdfx, "s");
+
+static int tdfx_setup(drm_device_t *dev)
+{
+	int i;
+	
+	atomic_set(&dev->ioctl_count, 0);
+	atomic_set(&dev->vma_count, 0);
+	dev->buf_use	  = 0;
+	atomic_set(&dev->buf_alloc, 0);
+
+	atomic_set(&dev->total_open, 0);
+	atomic_set(&dev->total_close, 0);
+	atomic_set(&dev->total_ioctl, 0);
+	atomic_set(&dev->total_irq, 0);
+	atomic_set(&dev->total_ctx, 0);
+	atomic_set(&dev->total_locks, 0);
+	atomic_set(&dev->total_unlocks, 0);
+	atomic_set(&dev->total_contends, 0);
+	atomic_set(&dev->total_sleeps, 0);
+
+	for (i = 0; i < DRM_HASH_SIZE; i++) {
+		dev->magiclist[i].head = NULL;
+		dev->magiclist[i].tail = NULL;
+	}
+	dev->maplist	    = NULL;
+	dev->map_count	    = 0;
+	dev->vmalist	    = NULL;
+	dev->lock.hw_lock   = NULL;
+	init_waitqueue_head(&dev->lock.lock_queue);
+	dev->queue_count    = 0;
+	dev->queue_reserved = 0;
+	dev->queue_slots    = 0;
+	dev->queuelist	    = NULL;
+	dev->irq	    = 0;
+	dev->context_flag   = 0;
+	dev->interrupt_flag = 0;
+	dev->dma            = 0;
+	dev->dma_flag	    = 0;
+	dev->last_context   = 0;
+	dev->last_switch    = 0;
+	dev->last_checked   = 0;
+	init_timer(&dev->timer);
+	init_waitqueue_head(&dev->context_wait);
+
+	dev->ctx_start	    = 0;
+	dev->lck_start	    = 0;
+	
+	dev->buf_rp	  = dev->buf;
+	dev->buf_wp	  = dev->buf;
+	dev->buf_end	  = dev->buf + DRM_BSZ;
+	dev->buf_async	  = NULL;
+	init_waitqueue_head(&dev->buf_readers);
+	init_waitqueue_head(&dev->buf_writers);
+
+	tdfx_res_ctx.handle=-1;
+			
+	DRM_DEBUG("\n");
+			
+	/* The kernel's context could be created here, but is now created
+	   in drm_dma_enqueue.	This is more resource-efficient for
+	   hardware that does not do DMA, but may mean that
+	   drm_select_queue fails between the time the interrupt is
+	   initialized and the time the queues are initialized. */
+			
+	return 0;
+}
+
+
+static int tdfx_takedown(drm_device_t *dev)
+{
+	int		  i;
+	drm_magic_entry_t *pt, *next;
+	drm_map_t	  *map;
+	drm_vma_entry_t	  *vma, *vma_next;
+
+	DRM_DEBUG("\n");
+
+	down(&dev->struct_sem);
+	del_timer(&dev->timer);
+	
+	if (dev->devname) {
+		drm_free(dev->devname, strlen(dev->devname)+1, DRM_MEM_DRIVER);
+		dev->devname = NULL;
+	}
+	
+	if (dev->unique) {
+		drm_free(dev->unique, strlen(dev->unique)+1, DRM_MEM_DRIVER);
+		dev->unique = NULL;
+		dev->unique_len = 0;
+	}
+				/* Clear pid list */
+	for (i = 0; i < DRM_HASH_SIZE; i++) {
+		for (pt = dev->magiclist[i].head; pt; pt = next) {
+			next = pt->next;
+			drm_free(pt, sizeof(*pt), DRM_MEM_MAGIC);
+		}
+		dev->magiclist[i].head = dev->magiclist[i].tail = NULL;
+	}
+	
+				/* Clear vma list (only built for debugging) */
+	if (dev->vmalist) {
+		for (vma = dev->vmalist; vma; vma = vma_next) {
+			vma_next = vma->next;
+			drm_free(vma, sizeof(*vma), DRM_MEM_VMAS);
+		}
+		dev->vmalist = NULL;
+	}
+	
+				/* Clear map area and mtrr information */
+	if (dev->maplist) {
+		for (i = 0; i < dev->map_count; i++) {
+			map = dev->maplist[i];
+			switch (map->type) {
+			case _DRM_REGISTERS:
+			case _DRM_FRAME_BUFFER:
+#ifdef CONFIG_MTRR
+				if (map->mtrr >= 0) {
+					int retcode;
+					retcode = mtrr_del(map->mtrr,
+							   map->offset,
+							   map->size);
+					DRM_DEBUG("mtrr_del = %d\n", retcode);
+				}
+#endif
+				drm_ioremapfree(map->handle, map->size);
+				break;
+			case _DRM_SHM:
+				drm_free_pages((unsigned long)map->handle,
+					       drm_order(map->size)
+					       - PAGE_SHIFT,
+					       DRM_MEM_SAREA);
+				break;
+			}
+			drm_free(map, sizeof(*map), DRM_MEM_MAPS);
+		}
+		drm_free(dev->maplist,
+			 dev->map_count * sizeof(*dev->maplist),
+			 DRM_MEM_MAPS);
+		dev->maplist   = NULL;
+		dev->map_count = 0;
+	}
+	
+	if (dev->lock.hw_lock) {
+		dev->lock.hw_lock    = NULL; /* SHM removed */
+		dev->lock.pid	     = 0;
+		wake_up_interruptible(&dev->lock.lock_queue);
+	}
+	up(&dev->struct_sem);
+	
+	return 0;
+}
+
+/* tdfx_init is called via init_module at module load time, or via
+ * linux/init/main.c (this is not currently supported). */
+
+int tdfx_init(void)
+{
+	int		      retcode;
+	drm_device_t	      *dev = &tdfx_device;
+
+	DRM_DEBUG("\n");
+
+	memset((void *)dev, 0, sizeof(*dev));
+	dev->count_lock	  = SPIN_LOCK_UNLOCKED;
+	sema_init(&dev->struct_sem, 1);
+	
+#ifdef MODULE
+	drm_parse_options(tdfx);
+#endif
+
+	if ((retcode = misc_register(&tdfx_misc))) {
+		DRM_ERROR("Cannot register \"%s\"\n", TDFX_NAME);
+		return retcode;
+	}
+	dev->device = MKDEV(MISC_MAJOR, tdfx_misc.minor);
+	dev->name   = TDFX_NAME;
+
+	drm_mem_init();
+	drm_proc_init(dev);
+
+	DRM_INFO("Initialized %s %d.%d.%d %s on minor %d\n",
+		 TDFX_NAME,
+		 TDFX_MAJOR,
+		 TDFX_MINOR,
+		 TDFX_PATCHLEVEL,
+		 TDFX_DATE,
+		 tdfx_misc.minor);
+	
+	return 0;
+}
+
+/* tdfx_cleanup is called via cleanup_module at module unload time. */
+
+void tdfx_cleanup(void)
+{
+	drm_device_t	      *dev = &tdfx_device;
+
+	DRM_DEBUG("\n");
+	
+	drm_proc_cleanup();
+	if (misc_deregister(&tdfx_misc)) {
+		DRM_ERROR("Cannot unload module\n");
+	} else {
+		DRM_INFO("Module unloaded\n");
+	}
+	tdfx_takedown(dev);
+}
+
+int tdfx_version(struct inode *inode, struct file *filp, unsigned int cmd,
+		  unsigned long arg)
+{
+	drm_version_t version;
+	int	      len;
+
+	copy_from_user_ret(&version,
+			   (drm_version_t *)arg,
+			   sizeof(version),
+			   -EFAULT);
+
+#define DRM_COPY(name,value)				     \
+	len = strlen(value);				     \
+	if (len > name##_len) len = name##_len;		     \
+	name##_len = strlen(value);			     \
+	if (len && name) {				     \
+		copy_to_user_ret(name, value, len, -EFAULT); \
+	}
+
+	version.version_major	   = TDFX_MAJOR;
+	version.version_minor	   = TDFX_MINOR;
+	version.version_patchlevel = TDFX_PATCHLEVEL;
+
+	DRM_COPY(version.name, TDFX_NAME);
+	DRM_COPY(version.date, TDFX_DATE);
+	DRM_COPY(version.desc, TDFX_DESC);
+
+	copy_to_user_ret((drm_version_t *)arg,
+			 &version,
+			 sizeof(version),
+			 -EFAULT);
+	return 0;
+}
+
+int tdfx_open(struct inode *inode, struct file *filp)
+{
+	drm_device_t  *dev    = &tdfx_device;
+	int	      retcode = 0;
+	
+	DRM_DEBUG("open_count = %d\n", dev->open_count);
+	if (!(retcode = drm_open_helper(inode, filp, dev))) {
+		MOD_INC_USE_COUNT;
+		atomic_inc(&dev->total_open);
+		spin_lock(&dev->count_lock);
+		if (!dev->open_count++) {
+			spin_unlock(&dev->count_lock);
+			return tdfx_setup(dev);
+		}
+		spin_unlock(&dev->count_lock);
+	}
+	return retcode;
+}
+
+int tdfx_release(struct inode *inode, struct file *filp)
+{
+	drm_file_t    *priv   = filp->private_data;
+	drm_device_t  *dev    = priv->dev;
+	int	      retcode = 0;
+
+	DRM_DEBUG("open_count = %d\n", dev->open_count);
+	if (!(retcode = drm_release(inode, filp))) {
+		MOD_DEC_USE_COUNT;
+		atomic_inc(&dev->total_close);
+		spin_lock(&dev->count_lock);
+		if (!--dev->open_count) {
+			if (atomic_read(&dev->ioctl_count) || dev->blocked) {
+				DRM_ERROR("Device busy: %d %d\n",
+					  atomic_read(&dev->ioctl_count),
+					  dev->blocked);
+				spin_unlock(&dev->count_lock);
+				return -EBUSY;
+			}
+			spin_unlock(&dev->count_lock);
+			return tdfx_takedown(dev);
+		}
+		spin_unlock(&dev->count_lock);
+	}
+	return retcode;
+}
+
+/* tdfx_ioctl is called whenever a process performs an ioctl on /dev/drm. */
+
+int tdfx_ioctl(struct inode *inode, struct file *filp, unsigned int cmd,
+		unsigned long arg)
+{
+	int		 nr	 = DRM_IOCTL_NR(cmd);
+	drm_file_t	 *priv	 = filp->private_data;
+	drm_device_t	 *dev	 = priv->dev;
+	int		 retcode = 0;
+	drm_ioctl_desc_t *ioctl;
+	drm_ioctl_t	 *func;
+
+	atomic_inc(&dev->ioctl_count);
+	atomic_inc(&dev->total_ioctl);
+	++priv->ioctl_count;
+	
+	DRM_DEBUG("pid = %d, cmd = 0x%02x, nr = 0x%02x, dev 0x%x, auth = %d\n",
+		  current->pid, cmd, nr, dev->device, priv->authenticated);
+
+	if (nr >= TDFX_IOCTL_COUNT) {
+		retcode = -EINVAL;
+	} else {
+		ioctl	  = &tdfx_ioctls[nr];
+		func	  = ioctl->func;
+
+		if (!func) {
+			DRM_DEBUG("no function\n");
+			retcode = -EINVAL;
+		} else if ((ioctl->root_only && !capable(CAP_SYS_ADMIN))
+			    || (ioctl->auth_needed && !priv->authenticated)) {
+			retcode = -EACCES;
+		} else {
+			retcode = (func)(inode, filp, cmd, arg);
+		}
+	}
+	
+	atomic_dec(&dev->ioctl_count);
+	return retcode;
+}
+
+int tdfx_lock(struct inode *inode, struct file *filp, unsigned int cmd,
+	      unsigned long arg)
+{
+        drm_file_t        *priv   = filp->private_data;
+        drm_device_t      *dev    = priv->dev;
+        DECLARE_WAITQUEUE(entry, current);
+        int               ret   = 0;
+        drm_lock_t        lock;
+#if DRM_DMA_HISTOGRAM
+        cycles_t          start;
+
+        dev->lck_start = start = get_cycles();
+#endif
+
+        copy_from_user_ret(&lock, (drm_lock_t *)arg, sizeof(lock), -EFAULT);
+
+        if (lock.context == DRM_KERNEL_CONTEXT) {
+                DRM_ERROR("Process %d using kernel context %d\n",
+                          current->pid, lock.context);
+                return -EINVAL;
+        }
+
+        DRM_DEBUG("%d (pid %d) requests lock (0x%08x), flags = 0x%08x\n",
+                  lock.context, current->pid, dev->lock.hw_lock->lock,
+                  lock.flags);
+
+#if 0
+				/* dev->queue_count == 0 right now for
+                                   tdfx.  FIXME? */
+        if (lock.context < 0 || lock.context >= dev->queue_count)
+                return -EINVAL;
+#endif
+        
+        if (!ret) {
+#if 0
+                if (_DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock)
+                    != lock.context) {
+                        long j = jiffies - dev->lock.lock_time;
+
+                        if (lock.context == tdfx_res_ctx.handle &&
+				j >= 0 && j < DRM_LOCK_SLICE) {
+                                /* Can't take lock if we just had it and
+                                   there is contention. */
+                                DRM_DEBUG("%d (pid %d) delayed j=%d dev=%d jiffies=%d\n",
+					lock.context, current->pid, j, 
+					dev->lock.lock_time, jiffies);
+                                current->state = TASK_INTERRUPTIBLE;
+				current->policy |= SCHED_YIELD;
+                                schedule_timeout(DRM_LOCK_SLICE-j);
+				DRM_DEBUG("jiffies=%d\n", jiffies);
+                        }
+                }
+#endif
+                add_wait_queue(&dev->lock.lock_queue, &entry);
+                for (;;) {
+                        if (!dev->lock.hw_lock) {
+                                /* Device has been unregistered */
+                                ret = -EINTR;
+                                break;
+                        }
+                        if (drm_lock_take(&dev->lock.hw_lock->lock,
+                                          lock.context)) {
+                                dev->lock.pid       = current->pid;
+                                dev->lock.lock_time = jiffies;
+                                atomic_inc(&dev->total_locks);
+                                break;  /* Got lock */
+                        }
+                        
+                                /* Contention */
+                        atomic_inc(&dev->total_sleeps);
+                        current->state = TASK_INTERRUPTIBLE;
+			current->policy |= SCHED_YIELD;
+                        schedule();
+                        if (signal_pending(current)) {
+                                ret = -ERESTARTSYS;
+                                break;
+                        }
+                }
+                current->state = TASK_RUNNING;
+                remove_wait_queue(&dev->lock.lock_queue, &entry);
+        }
+
+#if 0
+	if (!ret && dev->last_context != lock.context &&
+		lock.context != tdfx_res_ctx.handle &&
+		dev->last_context != tdfx_res_ctx.handle) {
+		add_wait_queue(&dev->context_wait, &entry);
+	        current->state = TASK_INTERRUPTIBLE;
+                /* PRE: dev->last_context != lock.context */
+	        tdfx_context_switch(dev, dev->last_context, lock.context);
+		/* POST: we will wait for the context
+                   switch and will dispatch on a later call
+                   when dev->last_context == lock.context
+                   NOTE WE HOLD THE LOCK THROUGHOUT THIS
+                   TIME! */
+		current->policy |= SCHED_YIELD;
+	        schedule();
+	        current->state = TASK_RUNNING;
+	        remove_wait_queue(&dev->context_wait, &entry);
+	        if (signal_pending(current)) {
+	                ret = -EINTR;
+	        } else if (dev->last_context != lock.context) {
+			DRM_ERROR("Context mismatch: %d %d\n",
+                        	dev->last_context, lock.context);
+	        }
+	}
+#endif
+
+        if (!ret) {
+                if (lock.flags & _DRM_LOCK_READY) {
+				/* Wait for space in DMA/FIFO */
+		}
+                if (lock.flags & _DRM_LOCK_QUIESCENT) {
+				/* Make hardware quiescent */
+#if 0
+                        tdfx_quiescent(dev);
+#endif
+		}
+        }
+        DRM_DEBUG("%d %s\n", lock.context, ret ? "interrupted" : "has lock");
+
+#if DRM_DMA_HISTOGRAM
+        atomic_inc(&dev->histo.lacq[drm_histogram_slot(get_cycles() - start)]);
+#endif
+        
+        return ret;
+}
+
+
+int tdfx_unlock(struct inode *inode, struct file *filp, unsigned int cmd,
+		 unsigned long arg)
+{
+	drm_file_t	  *priv	  = filp->private_data;
+	drm_device_t	  *dev	  = priv->dev;
+	drm_lock_t	  lock;
+
+	copy_from_user_ret(&lock, (drm_lock_t *)arg, sizeof(lock), -EFAULT);
+	
+	if (lock.context == DRM_KERNEL_CONTEXT) {
+		DRM_ERROR("Process %d using kernel context %d\n",
+			  current->pid, lock.context);
+		return -EINVAL;
+	}
+
+	DRM_DEBUG("%d frees lock (%d holds)\n",
+		  lock.context,
+		  _DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock));
+	atomic_inc(&dev->total_unlocks);
+	if (_DRM_LOCK_IS_CONT(dev->lock.hw_lock->lock))
+		atomic_inc(&dev->total_contends);
+	drm_lock_transfer(dev, &dev->lock.hw_lock->lock, DRM_KERNEL_CONTEXT);
+				/* FIXME: Try to send data to card here */
+	if (!dev->context_flag) {
+		if (drm_lock_free(dev, &dev->lock.hw_lock->lock,
+				  DRM_KERNEL_CONTEXT)) {
+			DRM_ERROR("\n");
+		}
+	}
+	
+	return 0;
+}
+
+module_init(tdfx_init);
+module_exit(tdfx_cleanup);
+
+/*
+ * tdfx_setup is called by the kernel to parse command-line options passed
+ * via the boot-loader (e.g., LILO).  It calls the insmod option routine,
+ * drm_parse_drm.
+ */
+static int __init tdfx_options(char *str)
+{
+	drm_parse_options(str);
+	return 1;
+}
+
+__setup("tdfx=", tdfx_options);

FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)