377 lines
9.6 KiB
C
377 lines
9.6 KiB
C
/*
|
||
* arch/m68k/atari/stram.c: Functions for ST-RAM allocations
|
||
*
|
||
* Copyright 1994-97 Roman Hodek <Roman.Hodek@informatik.uni-erlangen.de>
|
||
*
|
||
* This file is subject to the terms and conditions of the GNU General Public
|
||
* License. See the file COPYING in the main directory of this archive
|
||
* for more details.
|
||
*/
|
||
|
||
#include <linux/types.h>
|
||
#include <linux/kernel.h>
|
||
#include <linux/mm.h>
|
||
#include <linux/kdev_t.h>
|
||
#include <linux/major.h>
|
||
#include <linux/init.h>
|
||
#include <linux/slab.h>
|
||
#include <linux/vmalloc.h>
|
||
#include <linux/pagemap.h>
|
||
#include <linux/bootmem.h>
|
||
#include <linux/mount.h>
|
||
#include <linux/blkdev.h>
|
||
#include <linux/module.h>
|
||
|
||
#include <asm/setup.h>
|
||
#include <asm/machdep.h>
|
||
#include <asm/page.h>
|
||
#include <asm/pgtable.h>
|
||
#include <asm/atarihw.h>
|
||
#include <asm/atari_stram.h>
|
||
#include <asm/io.h>
|
||
|
||
#undef DEBUG
|
||
|
||
#ifdef DEBUG
|
||
#define DPRINTK(fmt,args...) printk( fmt, ##args )
|
||
#else
|
||
#define DPRINTK(fmt,args...)
|
||
#endif
|
||
|
||
#if defined(CONFIG_PROC_FS) && defined(CONFIG_STRAM_PROC)
|
||
/* abbrev for the && above... */
|
||
#define DO_PROC
|
||
#include <linux/proc_fs.h>
|
||
#include <linux/seq_file.h>
|
||
#endif
|
||
|
||
/*
|
||
* ++roman:
|
||
*
|
||
* New version of ST-Ram buffer allocation. Instead of using the
|
||
* 1 MB - 4 KB that remain when the ST-Ram chunk starts at $1000
|
||
* (1 MB granularity!), such buffers are reserved like this:
|
||
*
|
||
* - If the kernel resides in ST-Ram anyway, we can take the buffer
|
||
* from behind the current kernel data space the normal way
|
||
* (incrementing start_mem).
|
||
*
|
||
* - If the kernel is in TT-Ram, stram_init() initializes start and
|
||
* end of the available region. Buffers are allocated from there
|
||
* and mem_init() later marks the such used pages as reserved.
|
||
* Since each TT-Ram chunk is at least 4 MB in size, I hope there
|
||
* won't be an overrun of the ST-Ram region by normal kernel data
|
||
* space.
|
||
*
|
||
* For that, ST-Ram may only be allocated while kernel initialization
|
||
* is going on, or exactly: before mem_init() is called. There is also
|
||
* no provision now for freeing ST-Ram buffers. It seems that isn't
|
||
* really needed.
|
||
*
|
||
*/
|
||
|
||
/* Start and end (virtual) of ST-RAM */
|
||
static void *stram_start, *stram_end;
|
||
|
||
/* set after memory_init() executed and allocations via start_mem aren't
|
||
* possible anymore */
|
||
static int mem_init_done;
|
||
|
||
/* set if kernel is in ST-RAM */
|
||
static int kernel_in_stram;
|
||
|
||
typedef struct stram_block {
|
||
struct stram_block *next;
|
||
void *start;
|
||
unsigned long size;
|
||
unsigned flags;
|
||
const char *owner;
|
||
} BLOCK;
|
||
|
||
/* values for flags field */
|
||
#define BLOCK_FREE 0x01 /* free structure in the BLOCKs pool */
|
||
#define BLOCK_KMALLOCED 0x02 /* structure allocated by kmalloc() */
|
||
#define BLOCK_GFP 0x08 /* block allocated with __get_dma_pages() */
|
||
|
||
/* list of allocated blocks */
|
||
static BLOCK *alloc_list;
|
||
|
||
/* We can't always use kmalloc() to allocate BLOCK structures, since
|
||
* stram_alloc() can be called rather early. So we need some pool of
|
||
* statically allocated structures. 20 of them is more than enough, so in most
|
||
* cases we never should need to call kmalloc(). */
|
||
#define N_STATIC_BLOCKS 20
|
||
static BLOCK static_blocks[N_STATIC_BLOCKS];
|
||
|
||
/***************************** Prototypes *****************************/
|
||
|
||
static BLOCK *add_region( void *addr, unsigned long size );
|
||
static BLOCK *find_region( void *addr );
|
||
static int remove_region( BLOCK *block );
|
||
|
||
/************************* End of Prototypes **************************/
|
||
|
||
|
||
/* ------------------------------------------------------------------------ */
|
||
/* Public Interface */
|
||
/* ------------------------------------------------------------------------ */
|
||
|
||
/*
|
||
* This init function is called very early by atari/config.c
|
||
* It initializes some internal variables needed for stram_alloc()
|
||
*/
|
||
void __init atari_stram_init(void)
|
||
{
|
||
int i;
|
||
|
||
/* initialize static blocks */
|
||
for( i = 0; i < N_STATIC_BLOCKS; ++i )
|
||
static_blocks[i].flags = BLOCK_FREE;
|
||
|
||
/* determine whether kernel code resides in ST-RAM (then ST-RAM is the
|
||
* first memory block at virtual 0x0) */
|
||
stram_start = phys_to_virt(0);
|
||
kernel_in_stram = (stram_start == 0);
|
||
|
||
for( i = 0; i < m68k_num_memory; ++i ) {
|
||
if (m68k_memory[i].addr == 0) {
|
||
/* skip first 2kB or page (supervisor-only!) */
|
||
stram_end = stram_start + m68k_memory[i].size;
|
||
return;
|
||
}
|
||
}
|
||
/* Should never come here! (There is always ST-Ram!) */
|
||
panic( "atari_stram_init: no ST-RAM found!" );
|
||
}
|
||
|
||
|
||
/*
|
||
* This function is called from setup_arch() to reserve the pages needed for
|
||
* ST-RAM management.
|
||
*/
|
||
void __init atari_stram_reserve_pages(void *start_mem)
|
||
{
|
||
/* always reserve first page of ST-RAM, the first 2 kB are
|
||
* supervisor-only! */
|
||
if (!kernel_in_stram)
|
||
reserve_bootmem(0, PAGE_SIZE, BOOTMEM_DEFAULT);
|
||
|
||
}
|
||
|
||
void atari_stram_mem_init_hook (void)
|
||
{
|
||
mem_init_done = 1;
|
||
}
|
||
|
||
|
||
/*
|
||
* This is main public interface: somehow allocate a ST-RAM block
|
||
*
|
||
* - If we're before mem_init(), we have to make a static allocation. The
|
||
* region is taken in the kernel data area (if the kernel is in ST-RAM) or
|
||
* from the start of ST-RAM (if the kernel is in TT-RAM) and added to the
|
||
* rsvd_stram_* region. The ST-RAM is somewhere in the middle of kernel
|
||
* address space in the latter case.
|
||
*
|
||
* - If mem_init() already has been called, try with __get_dma_pages().
|
||
* This has the disadvantage that it's very hard to get more than 1 page,
|
||
* and it is likely to fail :-(
|
||
*
|
||
*/
|
||
void *atari_stram_alloc(long size, const char *owner)
|
||
{
|
||
void *addr = NULL;
|
||
BLOCK *block;
|
||
int flags;
|
||
|
||
DPRINTK("atari_stram_alloc(size=%08lx,owner=%s)\n", size, owner);
|
||
|
||
if (!mem_init_done)
|
||
return alloc_bootmem_low(size);
|
||
else {
|
||
/* After mem_init(): can only resort to __get_dma_pages() */
|
||
addr = (void *)__get_dma_pages(GFP_KERNEL, get_order(size));
|
||
flags = BLOCK_GFP;
|
||
DPRINTK( "atari_stram_alloc: after mem_init, "
|
||
"get_pages=%p\n", addr );
|
||
}
|
||
|
||
if (addr) {
|
||
if (!(block = add_region( addr, size ))) {
|
||
/* out of memory for BLOCK structure :-( */
|
||
DPRINTK( "atari_stram_alloc: out of mem for BLOCK -- "
|
||
"freeing again\n" );
|
||
free_pages((unsigned long)addr, get_order(size));
|
||
return( NULL );
|
||
}
|
||
block->owner = owner;
|
||
block->flags |= flags;
|
||
}
|
||
return( addr );
|
||
}
|
||
EXPORT_SYMBOL(atari_stram_alloc);
|
||
|
||
void atari_stram_free( void *addr )
|
||
|
||
{
|
||
BLOCK *block;
|
||
|
||
DPRINTK( "atari_stram_free(addr=%p)\n", addr );
|
||
|
||
if (!(block = find_region( addr ))) {
|
||
printk( KERN_ERR "Attempt to free non-allocated ST-RAM block at %p "
|
||
"from %p\n", addr, __builtin_return_address(0) );
|
||
return;
|
||
}
|
||
DPRINTK( "atari_stram_free: found block (%p): size=%08lx, owner=%s, "
|
||
"flags=%02x\n", block, block->size, block->owner, block->flags );
|
||
|
||
if (!(block->flags & BLOCK_GFP))
|
||
goto fail;
|
||
|
||
DPRINTK("atari_stram_free: is kmalloced, order_size=%d\n",
|
||
get_order(block->size));
|
||
free_pages((unsigned long)addr, get_order(block->size));
|
||
remove_region( block );
|
||
return;
|
||
|
||
fail:
|
||
printk( KERN_ERR "atari_stram_free: cannot free block at %p "
|
||
"(called from %p)\n", addr, __builtin_return_address(0) );
|
||
}
|
||
EXPORT_SYMBOL(atari_stram_free);
|
||
|
||
|
||
/* ------------------------------------------------------------------------ */
|
||
/* Region Management */
|
||
/* ------------------------------------------------------------------------ */
|
||
|
||
|
||
/* insert a region into the alloced list (sorted) */
|
||
static BLOCK *add_region( void *addr, unsigned long size )
|
||
{
|
||
BLOCK **p, *n = NULL;
|
||
int i;
|
||
|
||
for( i = 0; i < N_STATIC_BLOCKS; ++i ) {
|
||
if (static_blocks[i].flags & BLOCK_FREE) {
|
||
n = &static_blocks[i];
|
||
n->flags = 0;
|
||
break;
|
||
}
|
||
}
|
||
if (!n && mem_init_done) {
|
||
/* if statics block pool exhausted and we can call kmalloc() already
|
||
* (after mem_init()), try that */
|
||
n = kmalloc( sizeof(BLOCK), GFP_KERNEL );
|
||
if (n)
|
||
n->flags = BLOCK_KMALLOCED;
|
||
}
|
||
if (!n) {
|
||
printk( KERN_ERR "Out of memory for ST-RAM descriptor blocks\n" );
|
||
return( NULL );
|
||
}
|
||
n->start = addr;
|
||
n->size = size;
|
||
|
||
for( p = &alloc_list; *p; p = &((*p)->next) )
|
||
if ((*p)->start > addr) break;
|
||
n->next = *p;
|
||
*p = n;
|
||
|
||
return( n );
|
||
}
|
||
|
||
|
||
/* find a region (by start addr) in the alloced list */
|
||
static BLOCK *find_region( void *addr )
|
||
{
|
||
BLOCK *p;
|
||
|
||
for( p = alloc_list; p; p = p->next ) {
|
||
if (p->start == addr)
|
||
return( p );
|
||
if (p->start > addr)
|
||
break;
|
||
}
|
||
return( NULL );
|
||
}
|
||
|
||
|
||
/* remove a block from the alloced list */
|
||
static int remove_region( BLOCK *block )
|
||
{
|
||
BLOCK **p;
|
||
|
||
for( p = &alloc_list; *p; p = &((*p)->next) )
|
||
if (*p == block) break;
|
||
if (!*p)
|
||
return( 0 );
|
||
|
||
*p = block->next;
|
||
if (block->flags & BLOCK_KMALLOCED)
|
||
kfree( block );
|
||
else
|
||
block->flags |= BLOCK_FREE;
|
||
return( 1 );
|
||
}
|
||
|
||
|
||
|
||
/* ------------------------------------------------------------------------ */
|
||
/* /proc statistics file stuff */
|
||
/* ------------------------------------------------------------------------ */
|
||
|
||
#ifdef DO_PROC
|
||
|
||
#define PRINT_PROC(fmt,args...) seq_printf( m, fmt, ##args )
|
||
|
||
static int stram_proc_show(struct seq_file *m, void *v)
|
||
{
|
||
BLOCK *p;
|
||
|
||
PRINT_PROC("Total ST-RAM: %8u kB\n",
|
||
(stram_end - stram_start) >> 10);
|
||
PRINT_PROC( "Allocated regions:\n" );
|
||
for( p = alloc_list; p; p = p->next ) {
|
||
PRINT_PROC("0x%08lx-0x%08lx: %s (",
|
||
virt_to_phys(p->start),
|
||
virt_to_phys(p->start+p->size-1),
|
||
p->owner);
|
||
if (p->flags & BLOCK_GFP)
|
||
PRINT_PROC( "page-alloced)\n" );
|
||
else
|
||
PRINT_PROC( "??)\n" );
|
||
}
|
||
|
||
return 0;
|
||
}
|
||
|
||
static int stram_proc_open(struct inode *inode, struct file *file)
|
||
{
|
||
return single_open(file, stram_proc_show, NULL);
|
||
}
|
||
|
||
static const struct file_operations stram_proc_fops = {
|
||
.open = stram_proc_open,
|
||
.read = seq_read,
|
||
.llseek = seq_lseek,
|
||
.release = single_release,
|
||
};
|
||
|
||
static int __init proc_stram_init(void)
|
||
{
|
||
proc_create("stram", 0, NULL, &stram_proc_fops);
|
||
return 0;
|
||
}
|
||
module_init(proc_stram_init);
|
||
#endif
|
||
|
||
|
||
/*
|
||
* Local variables:
|
||
* c-indent-level: 4
|
||
* tab-width: 4
|
||
* End:
|
||
*/
|