blob: eea120229cdbc800a9540f534e49978adb0a446c [file] [log] [blame]
/*
* SPU core dump code
*
* (C) Copyright 2006 IBM Corp.
*
* Author: Dwayne Grant McConnell <decimal@us.ibm.com>
*
* 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, 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.
*/
#include <linux/elf.h>
#include <linux/file.h>
#include <linux/fdtable.h>
#include <linux/fs.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/syscalls.h>
#include <asm/uaccess.h>
#include "spufs.h"
static ssize_t do_coredump_read(int num, struct spu_context *ctx, void *buffer,
size_t size, loff_t *off)
{
u64 data;
int ret;
if (spufs_coredump_read[num].read)
return spufs_coredump_read[num].read(ctx, buffer, size, off);
data = spufs_coredump_read[num].get(ctx);
ret = snprintf(buffer, size, "0x%.16llx", data);
if (ret >= size)
return size;
return ++ret; /* count trailing NULL */
}
/*
* These are the only things you should do on a core-file: use only these
* functions to write out all the necessary info.
*/
static int spufs_dump_write(struct file *file, const void *addr, int nr, loff_t *foffset)
{
unsigned long limit = rlimit(RLIMIT_CORE);
ssize_t written;
if (*foffset + nr > limit)
return -EIO;
written = file->f_op->write(file, addr, nr, &file->f_pos);
*foffset += written;
if (written != nr)
return -EIO;
return 0;
}
static int spufs_dump_align(struct file *file, char *buf, loff_t new_off,
loff_t *foffset)
{
int rc, size;
size = min((loff_t)PAGE_SIZE, new_off - *foffset);
memset(buf, 0, size);
rc = 0;
while (rc == 0 && new_off > *foffset) {
size = min((loff_t)PAGE_SIZE, new_off - *foffset);
rc = spufs_dump_write(file, buf, size, foffset);
}
return rc;
}
static int spufs_ctx_note_size(struct spu_context *ctx, int dfd)
{
int i, sz, total = 0;
char *name;
char fullname[80];
for (i = 0; spufs_coredump_read[i].name != NULL; i++) {
name = spufs_coredump_read[i].name;
sz = spufs_coredump_read[i].size;
sprintf(fullname, "SPU/%d/%s", dfd, name);
total += sizeof(struct elf_note);
total += roundup(strlen(fullname) + 1, 4);
total += roundup(sz, 4);
}
return total;
}
/*
* The additional architecture-specific notes for Cell are various
* context files in the spu context.
*
* This function iterates over all open file descriptors and sees
* if they are a directory in spufs. In that case we use spufs
* internal functionality to dump them without needing to actually
* open the files.
*/
static struct spu_context *coredump_next_context(int *fd)
{
struct fdtable *fdt = files_fdtable(current->files);
struct file *file;
struct spu_context *ctx = NULL;
for (; *fd < fdt->max_fds; (*fd)++) {
if (!FD_ISSET(*fd, fdt->open_fds))
continue;
file = fcheck(*fd);
if (!file || file->f_op != &spufs_context_fops)
continue;
ctx = SPUFS_I(file->f_dentry->d_inode)->i_ctx;
if (ctx->flags & SPU_CREATE_NOSCHED)
continue;
break;
}
return ctx;
}
int spufs_coredump_extra_notes_size(void)
{
struct spu_context *ctx;
int size = 0, rc, fd;
fd = 0;
while ((ctx = coredump_next_context(&fd)) != NULL) {
rc = spu_acquire_saved(ctx);
if (rc)
break;
rc = spufs_ctx_note_size(ctx, fd);
spu_release_saved(ctx);
if (rc < 0)
break;
size += rc;
/* start searching the next fd next time */
fd++;
}
return size;
}
static int spufs_arch_write_note(struct spu_context *ctx, int i,
struct file *file, int dfd, loff_t *foffset)
{
loff_t pos = 0;
int sz, rc, nread, total = 0;
const int bufsz = PAGE_SIZE;
char *name;
char fullname[80], *buf;
struct elf_note en;
buf = (void *)get_zeroed_page(GFP_KERNEL);
if (!buf)
return -ENOMEM;
name = spufs_coredump_read[i].name;
sz = spufs_coredump_read[i].size;
sprintf(fullname, "SPU/%d/%s", dfd, name);
en.n_namesz = strlen(fullname) + 1;
en.n_descsz = sz;
en.n_type = NT_SPU;
rc = spufs_dump_write(file, &en, sizeof(en), foffset);
if (rc)
goto out;
rc = spufs_dump_write(file, fullname, en.n_namesz, foffset);
if (rc)
goto out;
rc = spufs_dump_align(file, buf, roundup(*foffset, 4), foffset);
if (rc)
goto out;
do {
nread = do_coredump_read(i, ctx, buf, bufsz, &pos);
if (nread > 0) {
rc = spufs_dump_write(file, buf, nread, foffset);
if (rc)
goto out;
total += nread;
}
} while (nread == bufsz && total < sz);
if (nread < 0) {
rc = nread;
goto out;
}
rc = spufs_dump_align(file, buf, roundup(*foffset - total + sz, 4),
foffset);
out:
free_page((unsigned long)buf);
return rc;
}
int spufs_coredump_extra_notes_write(struct file *file, loff_t *foffset)
{
struct spu_context *ctx;
int fd, j, rc;
fd = 0;
while ((ctx = coredump_next_context(&fd)) != NULL) {
rc = spu_acquire_saved(ctx);
if (rc)
return rc;
for (j = 0; spufs_coredump_read[j].name != NULL; j++) {
rc = spufs_arch_write_note(ctx, j, file, fd, foffset);
if (rc) {
spu_release_saved(ctx);
return rc;
}
}
spu_release_saved(ctx);
/* start searching the next fd next time */
fd++;
}
return 0;
}