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Diffstat (limited to 'drivers/staging/dt3155/allocator.c')
-rw-r--r-- | drivers/staging/dt3155/allocator.c | 294 |
1 files changed, 0 insertions, 294 deletions
diff --git a/drivers/staging/dt3155/allocator.c b/drivers/staging/dt3155/allocator.c deleted file mode 100644 index d33947b..0000000 --- a/drivers/staging/dt3155/allocator.c +++ /dev/null @@ -1,294 +0,0 @@ -/* - * allocator.c -- allocate after high_memory, if available - * - * NOTE: this is different from my previous allocator, the one that - * assembles pages, which revealed itself both slow and unreliable. - * - * Copyright (C) 1998 rubini@linux.it (Alessandro Rubini) - * - * 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, write to the Free Software - * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - * - --- Changes -- - - Date Programmer Description of changes made - ------------------------------------------------------------------- - 02-Aug-2002 NJC allocator now steps in 1MB increments, rather - than doubling its size each time. - Also, allocator_init(u32 *) now returns - (in the first arg) the size of the free - space. This is no longer consistent with - using the allocator as a module, and some changes - may be necessary for that purpose. This was - designed to work with the DT3155 driver, in - stand alone mode only!!! - 26-Oct-2009 SS Port to 2.6.30 kernel. - */ - - -#ifndef __KERNEL__ -# define __KERNEL__ -#endif -#ifndef MODULE -# define MODULE -#endif - - -#include <linux/sched.h> -#include <linux/kernel.h> -#include <linux/fs.h> -#include <linux/proc_fs.h> -#include <linux/errno.h> -#include <linux/types.h> -#include <linux/mm.h> /* PAGE_ALIGN() */ -#include <linux/io.h> -#include <linux/slab.h> - -#include <asm/page.h> - -#include "allocator.h" - -/*#define ALL_DEBUG*/ -#define ALL_MSG "allocator: " - -#undef PDEBUG /* undef it, just in case */ -#ifdef ALL_DEBUG -# define __static -# define DUMP_LIST() dump_list() -# ifdef __KERNEL__ - /* This one if debugging is on, and kernel space */ -# define PDEBUG(fmt, args...) printk(KERN_DEBUG ALL_MSG fmt, ## args) -# else - /* This one for user space */ -# define PDEBUG(fmt, args...) fprintf(stderr, fmt, ## args) -# endif -#else -# define PDEBUG(fmt, args...) /* not debugging: nothing */ -# define DUMP_LIST() -# define __static static -#endif - -#undef PDEBUGG -#define PDEBUGG(fmt, args...) -/*#define PDEBUGG(fmt, args...) printk( KERN_DEBUG ALL_MSG fmt, ## args)*/ - - -static int allocator_himem = 1; /* 0 = probe, pos. = megs, neg. = disable */ -static int allocator_step = 1; /* This is the step size in MB */ -static int allocator_probe = 1; /* This is a flag -- 1=probe, 0=don't probe */ - -static unsigned long allocator_buffer; /* physical address */ -static unsigned long allocator_buffer_size; /* kilobytes */ - -/* - * The allocator keeps a list of DMA areas, so multiple devices - * can coexist. The list is kept sorted by address - */ - -struct allocator_struct { - unsigned long address; - unsigned long size; - struct allocator_struct *next; -}; - -static struct allocator_struct *allocator_list; - -#ifdef ALL_DEBUG -static int dump_list(void) -{ - struct allocator_struct *ptr; - - PDEBUG("Current list:\n"); - for (ptr = allocator_list; ptr; ptr = ptr->next) - PDEBUG("0x%08lx (size %likB)\n", ptr->address, ptr->size>>10); - return 0; -} -#endif - -/* ======================================================================== - * This function is the actual allocator. - * - * If space is available in high memory (as detected at load time), that - * one is returned. The return value is a physical address (i.e., it can - * be used straight ahead for DMA, but needs remapping for program use). - */ - -unsigned long allocator_allocate_dma(unsigned long kilobytes, gfp_t flags) -{ - struct allocator_struct *ptr = allocator_list, *newptr; - unsigned long bytes = kilobytes << 10; - - /* check if high memory is available */ - if (!allocator_buffer) - return 0; - - /* Round it to a multiple of the pagesize */ - bytes = PAGE_ALIGN(bytes); - PDEBUG("request for %li bytes\n", bytes); - - while (ptr && ptr->next) { - if (ptr->next->address - (ptr->address + ptr->size) >= bytes) - break; /* enough space */ - ptr = ptr->next; - } - if (!ptr->next) { - DUMP_LIST(); - PDEBUG("alloc failed\n"); - return 0; /* end of list */ - } - newptr = kmalloc(sizeof(struct allocator_struct), flags); - if (!newptr) - return 0; - - /* ok, now stick it after ptr */ - newptr->address = ptr->address + ptr->size; - newptr->size = bytes; - newptr->next = ptr->next; - ptr->next = newptr; - - DUMP_LIST(); - PDEBUG("returning 0x%08lx\n", newptr->address); - return newptr->address; -} - -int allocator_free_dma(unsigned long address) -{ - struct allocator_struct *ptr = allocator_list, *prev; - - while (ptr && ptr->next) { - if (ptr->next->address == address) - break; - ptr = ptr->next; - } - /* the one being freed is ptr->next */ - prev = ptr; ptr = ptr->next; - - if (!ptr) { - pr_err(ALL_MSG "free_dma but add. not allocated\n"); - return -EINVAL; - } - PDEBUGG("freeing: %08lx (%li) next %08lx\n", ptr->address, ptr->size, - ptr->next->address); - prev->next = ptr->next; - kfree(ptr); - - /* dump_list(); */ - return 0; -} - -/* ======================================================================== - * Init and cleanup - * - * On cleanup everything is released. If the list is not empty, that a - * problem of our clients - */ -int allocator_init(u32 *allocator_max) -{ - /* check how much free memory is there */ - void *remapped; - unsigned long max; - unsigned long trial_size = allocator_himem<<20; - unsigned long last_trial = 0; - unsigned long step = allocator_step<<20; - unsigned long i = 0; - struct allocator_struct *head, *tail; - char test_string[] = "0123456789abcde"; /* 16 bytes */ - - PDEBUGG("himem = %i\n", allocator_himem); - if (allocator_himem < 0) /* don't even try */ - return -EINVAL; - - if (!trial_size) - trial_size = 1<<20; /* not specified: try one meg */ - - while (1) { - remapped = ioremap(__pa(high_memory), trial_size); - if (!remapped) { - PDEBUGG("%li megs failed!\n", trial_size>>20); - break; - } - PDEBUGG("Trying %li megs (at %p, %p)\n", trial_size>>20, - (void *)__pa(high_memory), remapped); - for (i = last_trial; i < trial_size; i += 16) { - strcpy((char *)(remapped)+i, test_string); - if (strcmp((char *)(remapped)+i, test_string)) - break; - } - iounmap((void *)remapped); - schedule(); - last_trial = trial_size; - if (i == trial_size) - trial_size += step; /* increment, if all went well */ - else { - PDEBUGG("%li megs copy test failed!\n", trial_size>>20); - break; - } - if (!allocator_probe) - break; - } - PDEBUG("%li megs (%li k, %li b)\n", i>>20, i>>10, i); - allocator_buffer_size = i>>10; /* kilobytes */ - allocator_buffer = __pa(high_memory); - if (!allocator_buffer_size) { - printk(KERN_WARNING ALL_MSG "no free high memory to use\n"); - return -ENOMEM; - } - - /* - * to simplify things, always have two cells in the list: - * the first and the last. This avoids some conditionals and - * extra code when allocating and deallocating: we only play - * in the middle of the list - */ - head = kmalloc(sizeof(struct allocator_struct), GFP_KERNEL); - if (!head) - return -ENOMEM; - tail = kmalloc(sizeof(struct allocator_struct), GFP_KERNEL); - if (!tail) { - kfree(head); - return -ENOMEM; - } - - max = allocator_buffer_size<<10; - - head->size = tail->size = 0; - head->address = allocator_buffer; - tail->address = allocator_buffer + max; - head->next = tail; - tail->next = NULL; - allocator_list = head; - - /* Back to the user code, in KB */ - *allocator_max = allocator_buffer_size; - - return 0; /* ok, ready */ -} - -void allocator_cleanup(void) -{ - struct allocator_struct *ptr, *next; - - for (ptr = allocator_list; ptr; ptr = next) { - next = ptr->next; - PDEBUG("freeing list: 0x%08lx\n", ptr->address); - kfree(ptr); - } - - allocator_buffer = 0; - allocator_buffer_size = 0; - allocator_list = NULL; -} - - |