/** * \file drm_context.h * IOCTLs for generic contexts * * \author Rickard E. (Rik) Faith * \author Gareth Hughes */ /* * Created: Fri Nov 24 18:31:37 2000 by gareth@valinux.com * * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas. * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California. * 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 * VA LINUX SYSTEMS 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. */ /* * ChangeLog: * 2001-11-16 Torsten Duwe * added context constructor/destructor hooks, * needed by SiS driver's memory management. */ #include "drmP.h" /******************************************************************/ /** \name Context bitmap support */ /*@{*/ /** * Free a handle from the context bitmap. * * \param dev DRM device. * \param ctx_handle context handle. * * Clears the bit specified by \p ctx_handle in drm_device::ctx_bitmap and the entry * in drm_device::context_sareas, while holding the drm_device::struct_sem * lock. */ void drm_ctxbitmap_free( drm_device_t *dev, int ctx_handle ) { if ( ctx_handle < 0 ) goto failed; if ( !dev->ctx_bitmap ) goto failed; if ( ctx_handle < DRM_MAX_CTXBITMAP ) { down(&dev->struct_sem); clear_bit( ctx_handle, dev->ctx_bitmap ); dev->context_sareas[ctx_handle] = NULL; up(&dev->struct_sem); return; } failed: DRM_ERROR( "Attempt to free invalid context handle: %d\n", ctx_handle ); return; } /** * Context bitmap allocation. * * \param dev DRM device. * \return (non-negative) context handle on success or a negative number on failure. * * Find the first zero bit in drm_device::ctx_bitmap and (re)allocates * drm_device::context_sareas to accommodate the new entry while holding the * drm_device::struct_sem lock. */ static int drm_ctxbitmap_next( drm_device_t *dev ) { int bit; if(!dev->ctx_bitmap) return -1; down(&dev->struct_sem); bit = find_first_zero_bit( dev->ctx_bitmap, DRM_MAX_CTXBITMAP ); if ( bit < DRM_MAX_CTXBITMAP ) { set_bit( bit, dev->ctx_bitmap ); DRM_DEBUG( "drm_ctxbitmap_next bit : %d\n", bit ); if((bit+1) > dev->max_context) { dev->max_context = (bit+1); if(dev->context_sareas) { drm_map_t **ctx_sareas; ctx_sareas = drm_realloc(dev->context_sareas, (dev->max_context - 1) * sizeof(*dev->context_sareas), dev->max_context * sizeof(*dev->context_sareas), DRM_MEM_MAPS); if(!ctx_sareas) { clear_bit(bit, dev->ctx_bitmap); up(&dev->struct_sem); return -1; } dev->context_sareas = ctx_sareas; dev->context_sareas[bit] = NULL; } else { /* max_context == 1 at this point */ dev->context_sareas = drm_alloc( dev->max_context * sizeof(*dev->context_sareas), DRM_MEM_MAPS); if(!dev->context_sareas) { clear_bit(bit, dev->ctx_bitmap); up(&dev->struct_sem); return -1; } dev->context_sareas[bit] = NULL; } } up(&dev->struct_sem); return bit; } up(&dev->struct_sem); return -1; } /** * Context bitmap initialization. * * \param dev DRM device. * * Allocates and initialize drm_device::ctx_bitmap and drm_device::context_sareas, while holding * the drm_device::struct_sem lock. */ int drm_ctxbitmap_init( drm_device_t *dev ) { int i; int temp; down(&dev->struct_sem); dev->ctx_bitmap = (unsigned long *) drm_alloc( PAGE_SIZE, DRM_MEM_CTXBITMAP ); if ( dev->ctx_bitmap == NULL ) { up(&dev->struct_sem); return -ENOMEM; } memset( (void *)dev->ctx_bitmap, 0, PAGE_SIZE ); dev->context_sareas = NULL; dev->max_context = -1; up(&dev->struct_sem); for ( i = 0 ; i < DRM_RESERVED_CONTEXTS ; i++ ) { temp = drm_ctxbitmap_next( dev ); DRM_DEBUG( "drm_ctxbitmap_init : %d\n", temp ); } return 0; } /** * Context bitmap cleanup. * * \param dev DRM device. * * Frees drm_device::ctx_bitmap and drm_device::context_sareas, while holding * the drm_device::struct_sem lock. */ void drm_ctxbitmap_cleanup( drm_device_t *dev ) { down(&dev->struct_sem); if( dev->context_sareas ) drm_free( dev->context_sareas, sizeof(*dev->context_sareas) * dev->max_context, DRM_MEM_MAPS ); drm_free( (void *)dev->ctx_bitmap, PAGE_SIZE, DRM_MEM_CTXBITMAP ); up(&dev->struct_sem); } /*@}*/ /******************************************************************/ /** \name Per Context SAREA Support */ /*@{*/ /** * Get per-context SAREA. * * \param inode device inode. * \param filp file pointer. * \param cmd command. * \param arg user argument pointing to a drm_ctx_priv_map structure. * \return zero on success or a negative number on failure. * * Gets the map from drm_device::context_sareas with the handle specified and * returns its handle. */ int drm_getsareactx(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg) { drm_file_t *priv = filp->private_data; drm_device_t *dev = priv->head->dev; drm_ctx_priv_map_t __user *argp = (void __user *)arg; drm_ctx_priv_map_t request; drm_map_t *map; if (copy_from_user(&request, argp, sizeof(request))) return -EFAULT; down(&dev->struct_sem); if (dev->max_context < 0 || request.ctx_id >= (unsigned) dev->max_context) { up(&dev->struct_sem); return -EINVAL; } map = dev->context_sareas[request.ctx_id]; up(&dev->struct_sem); request.handle = (void *) map->offset; if (copy_to_user(argp, &request, sizeof(request))) return -EFAULT; return 0; } /** * Set per-context SAREA. * * \param inode device inode. * \param filp file pointer. * \param cmd command. * \param arg user argument pointing to a drm_ctx_priv_map structure. * \return zero on success or a negative number on failure. * * Searches the mapping specified in \p arg and update the entry in * drm_device::context_sareas with it. */ int drm_setsareactx(struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg) { drm_file_t *priv = filp->private_data; drm_device_t *dev = priv->head->dev; drm_ctx_priv_map_t request; drm_map_t *map = NULL; drm_map_list_t *r_list = NULL; struct list_head *list; if (copy_from_user(&request, (drm_ctx_priv_map_t __user *)arg, sizeof(request))) return -EFAULT; down(&dev->struct_sem); list_for_each(list, &dev->maplist->head) { r_list = list_entry(list, drm_map_list_t, head); if (r_list->map && r_list->map->offset == (unsigned long) request.handle) goto found; } bad: up(&dev->struct_sem); return -EINVAL; found: map = r_list->map; if (!map) goto bad; if (dev->max_context < 0) goto bad; if (request.ctx_id >= (unsigned) dev->max_context) goto bad; dev->context_sareas[request.ctx_id] = map; up(&dev->struct_sem); return 0; } /*@}*/ /******************************************************************/ /** \name The actual DRM context handling routines */ /*@{*/ /** * Switch context. * * \param dev DRM device. * \param old old context handle. * \param new new context handle. * \return zero on success or a negative number on failure. * * Attempt to set drm_device::context_flag. */ int drm_context_switch( drm_device_t *dev, int old, int new ) { if ( test_and_set_bit( 0, &dev->context_flag ) ) { DRM_ERROR( "Reentering -- FIXME\n" ); return -EBUSY; } DRM_DEBUG( "Context switch from %d to %d\n", old, new ); if ( new == dev->last_context ) { clear_bit( 0, &dev->context_flag ); return 0; } return 0; } /** * Complete context switch. * * \param dev DRM device. * \param new new context handle. * \return zero on success or a negative number on failure. * * Updates drm_device::last_context and drm_device::last_switch. Verifies the * hardware lock is held, clears the drm_device::context_flag and wakes up * drm_device::context_wait. */ static int drm_context_switch_complete( drm_device_t *dev, int new ) { dev->last_context = new; /* PRE/POST: This is the _only_ writer. */ dev->last_switch = jiffies; if ( !_DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock) ) { DRM_ERROR( "Lock isn't held after context switch\n" ); } /* If a context switch is ever initiated when the kernel holds the lock, release that lock here. */ clear_bit( 0, &dev->context_flag ); wake_up( &dev->context_wait ); return 0; } /** * Reserve contexts. * * \param inode device inode. * \param filp file pointer. * \param cmd command. * \param arg user argument pointing to a drm_ctx_res structure. * \return zero on success or a negative number on failure. */ int drm_resctx( struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg ) { drm_ctx_res_t res; drm_ctx_t __user *argp = (void __user *)arg; drm_ctx_t ctx; int i; if ( copy_from_user( &res, argp, sizeof(res) ) ) return -EFAULT; if ( res.count >= DRM_RESERVED_CONTEXTS ) { memset( &ctx, 0, sizeof(ctx) ); for ( i = 0 ; i < DRM_RESERVED_CONTEXTS ; i++ ) { ctx.handle = i; if ( copy_to_user( &res.contexts[i], &ctx, sizeof(ctx) ) ) return -EFAULT; } } res.count = DRM_RESERVED_CONTEXTS; if ( copy_to_user( argp, &res, sizeof(res) ) ) return -EFAULT; return 0; } /** * Add context. * * \param inode device inode. * \param filp file pointer. * \param cmd command. * \param arg user argument pointing to a drm_ctx structure. * \return zero on success or a negative number on failure. * * Get a new handle for the context and copy to userspace. */ int drm_addctx( struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg ) { drm_file_t *priv = filp->private_data; drm_device_t *dev = priv->head->dev; drm_ctx_list_t * ctx_entry; drm_ctx_t __user *argp = (void __user *)arg; drm_ctx_t ctx; if ( copy_from_user( &ctx, argp, sizeof(ctx) ) ) return -EFAULT; ctx.handle = drm_ctxbitmap_next( dev ); if ( ctx.handle == DRM_KERNEL_CONTEXT ) { /* Skip kernel's context and get a new one. */ ctx.handle = drm_ctxbitmap_next( dev ); } DRM_DEBUG( "%d\n", ctx.handle ); if ( ctx.handle == -1 ) { DRM_DEBUG( "Not enough free contexts.\n" ); /* Should this return -EBUSY instead? */ return -ENOMEM; } if ( ctx.handle != DRM_KERNEL_CONTEXT ) { if (dev->driver->context_ctor) dev->driver->context_ctor(dev, ctx.handle); } ctx_entry = drm_alloc( sizeof(*ctx_entry), DRM_MEM_CTXLIST ); if ( !ctx_entry ) { DRM_DEBUG("out of memory\n"); return -ENOMEM; } INIT_LIST_HEAD( &ctx_entry->head ); ctx_entry->handle = ctx.handle; ctx_entry->tag = priv; down( &dev->ctxlist_sem ); list_add( &ctx_entry->head, &dev->ctxlist->head ); ++dev->ctx_count; up( &dev->ctxlist_sem ); if ( copy_to_user( argp, &ctx, sizeof(ctx) ) ) return -EFAULT; return 0; } int drm_modctx( struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg ) { /* This does nothing */ return 0; } /** * Get context. * * \param inode device inode. * \param filp file pointer. * \param cmd command. * \param arg user argument pointing to a drm_ctx structure. * \return zero on success or a negative number on failure. */ int drm_getctx( struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg ) { drm_ctx_t __user *argp = (void __user *)arg; drm_ctx_t ctx; if ( copy_from_user( &ctx, argp, sizeof(ctx) ) ) return -EFAULT; /* This is 0, because we don't handle any context flags */ ctx.flags = 0; if ( copy_to_user( argp, &ctx, sizeof(ctx) ) ) return -EFAULT; return 0; } /** * Switch context. * * \param inode device inode. * \param filp file pointer. * \param cmd command. * \param arg user argument pointing to a drm_ctx structure. * \return zero on success or a negative number on failure. * * Calls context_switch(). */ int drm_switchctx( struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg ) { drm_file_t *priv = filp->private_data; drm_device_t *dev = priv->head->dev; drm_ctx_t ctx; if ( copy_from_user( &ctx, (drm_ctx_t __user *)arg, sizeof(ctx) ) ) return -EFAULT; DRM_DEBUG( "%d\n", ctx.handle ); return drm_context_switch( dev, dev->last_context, ctx.handle ); } /** * New context. * * \param inode device inode. * \param filp file pointer. * \param cmd command. * \param arg user argument pointing to a drm_ctx structure. * \return zero on success or a negative number on failure. * * Calls context_switch_complete(). */ int drm_newctx( struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg ) { drm_file_t *priv = filp->private_data; drm_device_t *dev = priv->head->dev; drm_ctx_t ctx; if ( copy_from_user( &ctx, (drm_ctx_t __user *)arg, sizeof(ctx) ) ) return -EFAULT; DRM_DEBUG( "%d\n", ctx.handle ); drm_context_switch_complete( dev, ctx.handle ); return 0; } /** * Remove context. * * \param inode device inode. * \param filp file pointer. * \param cmd command. * \param arg user argument pointing to a drm_ctx structure. * \return zero on success or a negative number on failure. * * If not the special kernel context, calls ctxbitmap_free() to free the specified context. */ int drm_rmctx( struct inode *inode, struct file *filp, unsigned int cmd, unsigned long arg ) { drm_file_t *priv = filp->private_data; drm_device_t *dev = priv->head->dev; drm_ctx_t ctx; if ( copy_from_user( &ctx, (drm_ctx_t __user *)arg, sizeof(ctx) ) ) return -EFAULT; DRM_DEBUG( "%d\n", ctx.handle ); if ( ctx.handle == DRM_KERNEL_CONTEXT + 1 ) { priv->remove_auth_on_close = 1; } if ( ctx.handle != DRM_KERNEL_CONTEXT ) { if (dev->driver->context_dtor) dev->driver->context_dtor(dev, ctx.handle); drm_ctxbitmap_free( dev, ctx.handle ); } down( &dev->ctxlist_sem ); if ( !list_empty( &dev->ctxlist->head ) ) { drm_ctx_list_t *pos, *n; list_for_each_entry_safe( pos, n, &dev->ctxlist->head, head ) { if ( pos->handle == ctx.handle ) { list_del( &pos->head ); drm_free( pos, sizeof(*pos), DRM_MEM_CTXLIST ); --dev->ctx_count; } } } up( &dev->ctxlist_sem ); return 0; } /*@}*/