linux/drivers/nubus/proc.c
Finn Thain 6c8b89ea55 nubus: Call proc_mkdir() not more than once per slot directory
This patch fixes the following WARNING.

proc_dir_entry 'nubus/a' already registered
Modules linked in:
CPU: 0 PID: 1 Comm: swapper Tainted: G        W       4.13.0-00036-gd57552077387 #1
Stack from 01c1bd9c:
        01c1bd9c 003c2c8b 01c1bdc0 0001b0fe 00000000 00322f4a 01c43a20 01c43b0c
        01c8c420 01c1bde8 0001b1b8 003a4ac3 00000148 000faa26 00000009 00000000
        01c1bde0 003a4b6c 01c1bdfc 01c1be20 000faa26 003a4ac3 00000148 003a4b6c
        01c43a71 01c8c471 01c10000 00326430 0043d00c 00000005 01c71a00 0020bce0
        00322964 01c1be38 000fac04 01c43a20 01c8c420 01c1bee0 01c8c420 01c1be50
        000fac4c 01c1bee0 00000000 01c43a20 00000000 01c1bee8 0020bd26 01c1bee0
Call Trace: [<0001b0fe>] __warn+0xae/0xde
 [<00322f4a>] memcmp+0x0/0x5c
 [<0001b1b8>] warn_slowpath_fmt+0x2e/0x36
 [<000faa26>] proc_register+0xbe/0xd8
 [<000faa26>] proc_register+0xbe/0xd8
 [<00326430>] sprintf+0x0/0x20
 [<0020bce0>] nubus_proc_attach_device+0x0/0x1b8
 [<00322964>] strcpy+0x0/0x22
 [<000fac04>] proc_mkdir_data+0x64/0x96
 [<000fac4c>] proc_mkdir+0x16/0x1c
 [<0020bd26>] nubus_proc_attach_device+0x46/0x1b8
 [<0020bce0>] nubus_proc_attach_device+0x0/0x1b8
 [<00322964>] strcpy+0x0/0x22
 [<00001ba6>] kernel_pg_dir+0xba6/0x1000
 [<004339a2>] proc_bus_nubus_add_devices+0x1a/0x2e
 [<000faa40>] proc_create_data+0x0/0xf2
 [<0003297c>] parse_args+0x0/0x2d4
 [<00433a08>] nubus_proc_init+0x52/0x5a
 [<00433944>] nubus_init+0x0/0x44
 [<00433982>] nubus_init+0x3e/0x44
 [<000020dc>] do_one_initcall+0x38/0x196
 [<000020a4>] do_one_initcall+0x0/0x196
 [<0003297c>] parse_args+0x0/0x2d4
 [<00322964>] strcpy+0x0/0x22
 [<00040004>] __up_read+0xe/0x40
 [<004231d4>] repair_env_string+0x0/0x7a
 [<0042312e>] kernel_init_freeable+0xee/0x194
 [<00423146>] kernel_init_freeable+0x106/0x194
 [<00433944>] nubus_init+0x0/0x44
 [<000a6000>] kfree+0x0/0x156
 [<0032768c>] kernel_init+0x0/0xda
 [<00327698>] kernel_init+0xc/0xda
 [<0032768c>] kernel_init+0x0/0xda
 [<00002a90>] ret_from_kernel_thread+0xc/0x14
---[ end trace 14a6d619908ea253 ]---
------------[ cut here ]------------

This gets repeated with each additional functional reasource.

The problem here is the call to proc_mkdir() when the directory already
exists. Each nubus_board gets a directory, such as /proc/bus/nubus/s/
where s is the hex slot number. Therefore, store the 'procdir' pointer
in struct nubus_board instead of struct nubus_dev.

Tested-by: Stan Johnson <userm57@yahoo.com>
Signed-off-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2018-01-16 16:47:29 +01:00

239 lines
5.8 KiB
C

// SPDX-License-Identifier: GPL-2.0
/* drivers/nubus/proc.c: Proc FS interface for NuBus.
By David Huggins-Daines <dhd@debian.org>
Much code and many ideas from drivers/pci/proc.c:
Copyright (c) 1997, 1998 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
This is initially based on the Zorro and PCI interfaces. However,
it works somewhat differently. The intent is to provide a
structure in /proc analogous to the structure of the NuBus ROM
resources.
Therefore each NuBus device is in fact a directory, which may in
turn contain subdirectories. The "files" correspond to NuBus
resource records. For those types of records which we know how to
convert to formats that are meaningful to userspace (mostly just
icons) these files will provide "cooked" data. Otherwise they will
simply provide raw access (read-only of course) to the ROM. */
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/nubus.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/uaccess.h>
#include <asm/byteorder.h>
static int
nubus_devices_proc_show(struct seq_file *m, void *v)
{
struct nubus_dev *dev = nubus_devices;
while (dev) {
seq_printf(m, "%x\t%04x %04x %04x %04x",
dev->board->slot,
dev->category,
dev->type,
dev->dr_sw,
dev->dr_hw);
seq_printf(m, "\t%08lx\n", dev->board->slot_addr);
dev = dev->next;
}
return 0;
}
static int nubus_devices_proc_open(struct inode *inode, struct file *file)
{
return single_open(file, nubus_devices_proc_show, NULL);
}
static const struct file_operations nubus_devices_proc_fops = {
.open = nubus_devices_proc_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static struct proc_dir_entry *proc_bus_nubus_dir;
static const struct file_operations nubus_proc_subdir_fops = {
#warning Need to set some I/O handlers here
};
static void nubus_proc_subdir(struct nubus_dev* dev,
struct proc_dir_entry* parent,
struct nubus_dir* dir)
{
struct nubus_dirent ent;
/* Some of these are directories, others aren't */
while (nubus_readdir(dir, &ent) != -1) {
char name[9];
struct proc_dir_entry* e;
snprintf(name, sizeof(name), "%x", ent.type);
e = proc_create(name, S_IFREG | S_IRUGO | S_IWUSR, parent,
&nubus_proc_subdir_fops);
if (!e)
return;
}
}
/* Can't do this recursively since the root directory is structured
somewhat differently from the subdirectories */
static void nubus_proc_populate(struct nubus_dev* dev,
struct proc_dir_entry* parent,
struct nubus_dir* root)
{
struct nubus_dirent ent;
/* We know these are all directories (board resource + one or
more functional resources) */
while (nubus_readdir(root, &ent) != -1) {
char name[9];
struct proc_dir_entry* e;
struct nubus_dir dir;
snprintf(name, sizeof(name), "%x", ent.type);
e = proc_mkdir(name, parent);
if (!e) return;
/* And descend */
if (nubus_get_subdir(&ent, &dir) == -1) {
/* This shouldn't happen */
printk(KERN_ERR "NuBus root directory node %x:%x has no subdir!\n",
dev->board->slot, ent.type);
continue;
} else {
nubus_proc_subdir(dev, e, &dir);
}
}
}
int nubus_proc_attach_device(struct nubus_dev *dev)
{
struct proc_dir_entry *e;
struct nubus_dir root;
char name[9];
if (dev == NULL) {
printk(KERN_ERR
"NULL pointer in nubus_proc_attach_device, shoot the programmer!\n");
return -1;
}
if (dev->board == NULL) {
printk(KERN_ERR
"NULL pointer in nubus_proc_attach_device, shoot the programmer!\n");
printk("dev = %p, dev->board = %p\n", dev, dev->board);
return -1;
}
if (dev->board->procdir)
return 0;
/* Create a directory */
snprintf(name, sizeof(name), "%x", dev->board->slot);
e = proc_mkdir(name, proc_bus_nubus_dir);
dev->board->procdir = e;
if (!e)
return -ENOMEM;
/* Now recursively populate it with files */
nubus_get_root_dir(dev->board, &root);
nubus_proc_populate(dev, e, &root);
return 0;
}
EXPORT_SYMBOL(nubus_proc_attach_device);
/*
* /proc/nubus stuff
*/
static int nubus_proc_show(struct seq_file *m, void *v)
{
const struct nubus_board *board = v;
/* Display header on line 1 */
if (v == SEQ_START_TOKEN)
seq_puts(m, "Nubus devices found:\n");
else
seq_printf(m, "Slot %X: %s\n", board->slot, board->name);
return 0;
}
static void *nubus_proc_start(struct seq_file *m, loff_t *_pos)
{
struct nubus_board *board;
unsigned pos;
if (*_pos > LONG_MAX)
return NULL;
pos = *_pos;
if (pos == 0)
return SEQ_START_TOKEN;
for (board = nubus_boards; board; board = board->next)
if (--pos == 0)
break;
return board;
}
static void *nubus_proc_next(struct seq_file *p, void *v, loff_t *_pos)
{
/* Walk the list of NuBus boards */
struct nubus_board *board = v;
++*_pos;
if (v == SEQ_START_TOKEN)
board = nubus_boards;
else if (board)
board = board->next;
return board;
}
static void nubus_proc_stop(struct seq_file *p, void *v)
{
}
static const struct seq_operations nubus_proc_seqops = {
.start = nubus_proc_start,
.next = nubus_proc_next,
.stop = nubus_proc_stop,
.show = nubus_proc_show,
};
static int nubus_proc_open(struct inode *inode, struct file *file)
{
return seq_open(file, &nubus_proc_seqops);
}
static const struct file_operations nubus_proc_fops = {
.open = nubus_proc_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
void __init proc_bus_nubus_add_devices(void)
{
struct nubus_dev *dev;
for(dev = nubus_devices; dev; dev = dev->next)
nubus_proc_attach_device(dev);
}
void __init nubus_proc_init(void)
{
proc_create("nubus", 0, NULL, &nubus_proc_fops);
if (!MACH_IS_MAC)
return;
proc_bus_nubus_dir = proc_mkdir("bus/nubus", NULL);
proc_create("devices", 0, proc_bus_nubus_dir, &nubus_devices_proc_fops);
proc_bus_nubus_add_devices();
}