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linux/fs/afs/proc.c
Josh Triplett 99fc705996 [PATCH] afs: add lock annotations to afs_proc_cell_servers_{start,stop}
afs_proc_cell_servers_start acquires a lock, and afs_proc_cell_servers_stop
releases that lock.  Add lock annotations to these two functions so that
sparse can check callers for lock pairing, and so that sparse will not
complain about these functions since they intentionally use locks in this
manner.

Signed-off-by: Josh Triplett <josh@freedesktop.org>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29 09:18:07 -07:00

860 lines
21 KiB
C

/* proc.c: /proc interface for AFS
*
* Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.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 of the License, or (at your option) any later version.
*/
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include "cell.h"
#include "volume.h"
#include <asm/uaccess.h>
#include "internal.h"
static struct proc_dir_entry *proc_afs;
static int afs_proc_cells_open(struct inode *inode, struct file *file);
static void *afs_proc_cells_start(struct seq_file *p, loff_t *pos);
static void *afs_proc_cells_next(struct seq_file *p, void *v, loff_t *pos);
static void afs_proc_cells_stop(struct seq_file *p, void *v);
static int afs_proc_cells_show(struct seq_file *m, void *v);
static ssize_t afs_proc_cells_write(struct file *file, const char __user *buf,
size_t size, loff_t *_pos);
static struct seq_operations afs_proc_cells_ops = {
.start = afs_proc_cells_start,
.next = afs_proc_cells_next,
.stop = afs_proc_cells_stop,
.show = afs_proc_cells_show,
};
static const struct file_operations afs_proc_cells_fops = {
.open = afs_proc_cells_open,
.read = seq_read,
.write = afs_proc_cells_write,
.llseek = seq_lseek,
.release = seq_release,
};
static int afs_proc_rootcell_open(struct inode *inode, struct file *file);
static int afs_proc_rootcell_release(struct inode *inode, struct file *file);
static ssize_t afs_proc_rootcell_read(struct file *file, char __user *buf,
size_t size, loff_t *_pos);
static ssize_t afs_proc_rootcell_write(struct file *file,
const char __user *buf,
size_t size, loff_t *_pos);
static const struct file_operations afs_proc_rootcell_fops = {
.open = afs_proc_rootcell_open,
.read = afs_proc_rootcell_read,
.write = afs_proc_rootcell_write,
.llseek = no_llseek,
.release = afs_proc_rootcell_release
};
static int afs_proc_cell_volumes_open(struct inode *inode, struct file *file);
static int afs_proc_cell_volumes_release(struct inode *inode,
struct file *file);
static void *afs_proc_cell_volumes_start(struct seq_file *p, loff_t *pos);
static void *afs_proc_cell_volumes_next(struct seq_file *p, void *v,
loff_t *pos);
static void afs_proc_cell_volumes_stop(struct seq_file *p, void *v);
static int afs_proc_cell_volumes_show(struct seq_file *m, void *v);
static struct seq_operations afs_proc_cell_volumes_ops = {
.start = afs_proc_cell_volumes_start,
.next = afs_proc_cell_volumes_next,
.stop = afs_proc_cell_volumes_stop,
.show = afs_proc_cell_volumes_show,
};
static const struct file_operations afs_proc_cell_volumes_fops = {
.open = afs_proc_cell_volumes_open,
.read = seq_read,
.llseek = seq_lseek,
.release = afs_proc_cell_volumes_release,
};
static int afs_proc_cell_vlservers_open(struct inode *inode,
struct file *file);
static int afs_proc_cell_vlservers_release(struct inode *inode,
struct file *file);
static void *afs_proc_cell_vlservers_start(struct seq_file *p, loff_t *pos);
static void *afs_proc_cell_vlservers_next(struct seq_file *p, void *v,
loff_t *pos);
static void afs_proc_cell_vlservers_stop(struct seq_file *p, void *v);
static int afs_proc_cell_vlservers_show(struct seq_file *m, void *v);
static struct seq_operations afs_proc_cell_vlservers_ops = {
.start = afs_proc_cell_vlservers_start,
.next = afs_proc_cell_vlservers_next,
.stop = afs_proc_cell_vlservers_stop,
.show = afs_proc_cell_vlservers_show,
};
static const struct file_operations afs_proc_cell_vlservers_fops = {
.open = afs_proc_cell_vlservers_open,
.read = seq_read,
.llseek = seq_lseek,
.release = afs_proc_cell_vlservers_release,
};
static int afs_proc_cell_servers_open(struct inode *inode, struct file *file);
static int afs_proc_cell_servers_release(struct inode *inode,
struct file *file);
static void *afs_proc_cell_servers_start(struct seq_file *p, loff_t *pos);
static void *afs_proc_cell_servers_next(struct seq_file *p, void *v,
loff_t *pos);
static void afs_proc_cell_servers_stop(struct seq_file *p, void *v);
static int afs_proc_cell_servers_show(struct seq_file *m, void *v);
static struct seq_operations afs_proc_cell_servers_ops = {
.start = afs_proc_cell_servers_start,
.next = afs_proc_cell_servers_next,
.stop = afs_proc_cell_servers_stop,
.show = afs_proc_cell_servers_show,
};
static const struct file_operations afs_proc_cell_servers_fops = {
.open = afs_proc_cell_servers_open,
.read = seq_read,
.llseek = seq_lseek,
.release = afs_proc_cell_servers_release,
};
/*****************************************************************************/
/*
* initialise the /proc/fs/afs/ directory
*/
int afs_proc_init(void)
{
struct proc_dir_entry *p;
_enter("");
proc_afs = proc_mkdir("fs/afs", NULL);
if (!proc_afs)
goto error;
proc_afs->owner = THIS_MODULE;
p = create_proc_entry("cells", 0, proc_afs);
if (!p)
goto error_proc;
p->proc_fops = &afs_proc_cells_fops;
p->owner = THIS_MODULE;
p = create_proc_entry("rootcell", 0, proc_afs);
if (!p)
goto error_cells;
p->proc_fops = &afs_proc_rootcell_fops;
p->owner = THIS_MODULE;
_leave(" = 0");
return 0;
error_cells:
remove_proc_entry("cells", proc_afs);
error_proc:
remove_proc_entry("fs/afs", NULL);
error:
_leave(" = -ENOMEM");
return -ENOMEM;
} /* end afs_proc_init() */
/*****************************************************************************/
/*
* clean up the /proc/fs/afs/ directory
*/
void afs_proc_cleanup(void)
{
remove_proc_entry("cells", proc_afs);
remove_proc_entry("fs/afs", NULL);
} /* end afs_proc_cleanup() */
/*****************************************************************************/
/*
* open "/proc/fs/afs/cells" which provides a summary of extant cells
*/
static int afs_proc_cells_open(struct inode *inode, struct file *file)
{
struct seq_file *m;
int ret;
ret = seq_open(file, &afs_proc_cells_ops);
if (ret < 0)
return ret;
m = file->private_data;
m->private = PDE(inode)->data;
return 0;
} /* end afs_proc_cells_open() */
/*****************************************************************************/
/*
* set up the iterator to start reading from the cells list and return the
* first item
*/
static void *afs_proc_cells_start(struct seq_file *m, loff_t *_pos)
{
struct list_head *_p;
loff_t pos = *_pos;
/* lock the list against modification */
down_read(&afs_proc_cells_sem);
/* allow for the header line */
if (!pos)
return (void *) 1;
pos--;
/* find the n'th element in the list */
list_for_each(_p, &afs_proc_cells)
if (!pos--)
break;
return _p != &afs_proc_cells ? _p : NULL;
} /* end afs_proc_cells_start() */
/*****************************************************************************/
/*
* move to next cell in cells list
*/
static void *afs_proc_cells_next(struct seq_file *p, void *v, loff_t *pos)
{
struct list_head *_p;
(*pos)++;
_p = v;
_p = v == (void *) 1 ? afs_proc_cells.next : _p->next;
return _p != &afs_proc_cells ? _p : NULL;
} /* end afs_proc_cells_next() */
/*****************************************************************************/
/*
* clean up after reading from the cells list
*/
static void afs_proc_cells_stop(struct seq_file *p, void *v)
{
up_read(&afs_proc_cells_sem);
} /* end afs_proc_cells_stop() */
/*****************************************************************************/
/*
* display a header line followed by a load of cell lines
*/
static int afs_proc_cells_show(struct seq_file *m, void *v)
{
struct afs_cell *cell = list_entry(v, struct afs_cell, proc_link);
/* display header on line 1 */
if (v == (void *) 1) {
seq_puts(m, "USE NAME\n");
return 0;
}
/* display one cell per line on subsequent lines */
seq_printf(m, "%3d %s\n", atomic_read(&cell->usage), cell->name);
return 0;
} /* end afs_proc_cells_show() */
/*****************************************************************************/
/*
* handle writes to /proc/fs/afs/cells
* - to add cells: echo "add <cellname> <IP>[:<IP>][:<IP>]"
*/
static ssize_t afs_proc_cells_write(struct file *file, const char __user *buf,
size_t size, loff_t *_pos)
{
char *kbuf, *name, *args;
int ret;
/* start by dragging the command into memory */
if (size <= 1 || size >= PAGE_SIZE)
return -EINVAL;
kbuf = kmalloc(size + 1, GFP_KERNEL);
if (!kbuf)
return -ENOMEM;
ret = -EFAULT;
if (copy_from_user(kbuf, buf, size) != 0)
goto done;
kbuf[size] = 0;
/* trim to first NL */
name = memchr(kbuf, '\n', size);
if (name)
*name = 0;
/* split into command, name and argslist */
name = strchr(kbuf, ' ');
if (!name)
goto inval;
do {
*name++ = 0;
} while(*name == ' ');
if (!*name)
goto inval;
args = strchr(name, ' ');
if (!args)
goto inval;
do {
*args++ = 0;
} while(*args == ' ');
if (!*args)
goto inval;
/* determine command to perform */
_debug("cmd=%s name=%s args=%s", kbuf, name, args);
if (strcmp(kbuf, "add") == 0) {
struct afs_cell *cell;
ret = afs_cell_create(name, args, &cell);
if (ret < 0)
goto done;
printk("kAFS: Added new cell '%s'\n", name);
}
else {
goto inval;
}
ret = size;
done:
kfree(kbuf);
_leave(" = %d", ret);
return ret;
inval:
ret = -EINVAL;
printk("kAFS: Invalid Command on /proc/fs/afs/cells file\n");
goto done;
} /* end afs_proc_cells_write() */
/*****************************************************************************/
/*
* Stubs for /proc/fs/afs/rootcell
*/
static int afs_proc_rootcell_open(struct inode *inode, struct file *file)
{
return 0;
}
static int afs_proc_rootcell_release(struct inode *inode, struct file *file)
{
return 0;
}
static ssize_t afs_proc_rootcell_read(struct file *file, char __user *buf,
size_t size, loff_t *_pos)
{
return 0;
}
/*****************************************************************************/
/*
* handle writes to /proc/fs/afs/rootcell
* - to initialize rootcell: echo "cell.name:192.168.231.14"
*/
static ssize_t afs_proc_rootcell_write(struct file *file,
const char __user *buf,
size_t size, loff_t *_pos)
{
char *kbuf, *s;
int ret;
/* start by dragging the command into memory */
if (size <= 1 || size >= PAGE_SIZE)
return -EINVAL;
ret = -ENOMEM;
kbuf = kmalloc(size + 1, GFP_KERNEL);
if (!kbuf)
goto nomem;
ret = -EFAULT;
if (copy_from_user(kbuf, buf, size) != 0)
goto infault;
kbuf[size] = 0;
/* trim to first NL */
s = memchr(kbuf, '\n', size);
if (s)
*s = 0;
/* determine command to perform */
_debug("rootcell=%s", kbuf);
ret = afs_cell_init(kbuf);
if (ret >= 0)
ret = size; /* consume everything, always */
infault:
kfree(kbuf);
nomem:
_leave(" = %d", ret);
return ret;
} /* end afs_proc_rootcell_write() */
/*****************************************************************************/
/*
* initialise /proc/fs/afs/<cell>/
*/
int afs_proc_cell_setup(struct afs_cell *cell)
{
struct proc_dir_entry *p;
_enter("%p{%s}", cell, cell->name);
cell->proc_dir = proc_mkdir(cell->name, proc_afs);
if (!cell->proc_dir)
return -ENOMEM;
p = create_proc_entry("servers", 0, cell->proc_dir);
if (!p)
goto error_proc;
p->proc_fops = &afs_proc_cell_servers_fops;
p->owner = THIS_MODULE;
p->data = cell;
p = create_proc_entry("vlservers", 0, cell->proc_dir);
if (!p)
goto error_servers;
p->proc_fops = &afs_proc_cell_vlservers_fops;
p->owner = THIS_MODULE;
p->data = cell;
p = create_proc_entry("volumes", 0, cell->proc_dir);
if (!p)
goto error_vlservers;
p->proc_fops = &afs_proc_cell_volumes_fops;
p->owner = THIS_MODULE;
p->data = cell;
_leave(" = 0");
return 0;
error_vlservers:
remove_proc_entry("vlservers", cell->proc_dir);
error_servers:
remove_proc_entry("servers", cell->proc_dir);
error_proc:
remove_proc_entry(cell->name, proc_afs);
_leave(" = -ENOMEM");
return -ENOMEM;
} /* end afs_proc_cell_setup() */
/*****************************************************************************/
/*
* remove /proc/fs/afs/<cell>/
*/
void afs_proc_cell_remove(struct afs_cell *cell)
{
_enter("");
remove_proc_entry("volumes", cell->proc_dir);
remove_proc_entry("vlservers", cell->proc_dir);
remove_proc_entry("servers", cell->proc_dir);
remove_proc_entry(cell->name, proc_afs);
_leave("");
} /* end afs_proc_cell_remove() */
/*****************************************************************************/
/*
* open "/proc/fs/afs/<cell>/volumes" which provides a summary of extant cells
*/
static int afs_proc_cell_volumes_open(struct inode *inode, struct file *file)
{
struct afs_cell *cell;
struct seq_file *m;
int ret;
cell = afs_get_cell_maybe((struct afs_cell **) &PDE(inode)->data);
if (!cell)
return -ENOENT;
ret = seq_open(file, &afs_proc_cell_volumes_ops);
if (ret < 0)
return ret;
m = file->private_data;
m->private = cell;
return 0;
} /* end afs_proc_cell_volumes_open() */
/*****************************************************************************/
/*
* close the file and release the ref to the cell
*/
static int afs_proc_cell_volumes_release(struct inode *inode, struct file *file)
{
struct afs_cell *cell = PDE(inode)->data;
int ret;
ret = seq_release(inode,file);
afs_put_cell(cell);
return ret;
} /* end afs_proc_cell_volumes_release() */
/*****************************************************************************/
/*
* set up the iterator to start reading from the cells list and return the
* first item
*/
static void *afs_proc_cell_volumes_start(struct seq_file *m, loff_t *_pos)
{
struct list_head *_p;
struct afs_cell *cell = m->private;
loff_t pos = *_pos;
_enter("cell=%p pos=%Ld", cell, *_pos);
/* lock the list against modification */
down_read(&cell->vl_sem);
/* allow for the header line */
if (!pos)
return (void *) 1;
pos--;
/* find the n'th element in the list */
list_for_each(_p, &cell->vl_list)
if (!pos--)
break;
return _p != &cell->vl_list ? _p : NULL;
} /* end afs_proc_cell_volumes_start() */
/*****************************************************************************/
/*
* move to next cell in cells list
*/
static void *afs_proc_cell_volumes_next(struct seq_file *p, void *v,
loff_t *_pos)
{
struct list_head *_p;
struct afs_cell *cell = p->private;
_enter("cell=%p pos=%Ld", cell, *_pos);
(*_pos)++;
_p = v;
_p = v == (void *) 1 ? cell->vl_list.next : _p->next;
return _p != &cell->vl_list ? _p : NULL;
} /* end afs_proc_cell_volumes_next() */
/*****************************************************************************/
/*
* clean up after reading from the cells list
*/
static void afs_proc_cell_volumes_stop(struct seq_file *p, void *v)
{
struct afs_cell *cell = p->private;
up_read(&cell->vl_sem);
} /* end afs_proc_cell_volumes_stop() */
/*****************************************************************************/
/*
* display a header line followed by a load of volume lines
*/
static int afs_proc_cell_volumes_show(struct seq_file *m, void *v)
{
struct afs_vlocation *vlocation =
list_entry(v, struct afs_vlocation, link);
/* display header on line 1 */
if (v == (void *) 1) {
seq_puts(m, "USE VLID[0] VLID[1] VLID[2] NAME\n");
return 0;
}
/* display one cell per line on subsequent lines */
seq_printf(m, "%3d %08x %08x %08x %s\n",
atomic_read(&vlocation->usage),
vlocation->vldb.vid[0],
vlocation->vldb.vid[1],
vlocation->vldb.vid[2],
vlocation->vldb.name
);
return 0;
} /* end afs_proc_cell_volumes_show() */
/*****************************************************************************/
/*
* open "/proc/fs/afs/<cell>/vlservers" which provides a list of volume
* location server
*/
static int afs_proc_cell_vlservers_open(struct inode *inode, struct file *file)
{
struct afs_cell *cell;
struct seq_file *m;
int ret;
cell = afs_get_cell_maybe((struct afs_cell**)&PDE(inode)->data);
if (!cell)
return -ENOENT;
ret = seq_open(file,&afs_proc_cell_vlservers_ops);
if (ret<0)
return ret;
m = file->private_data;
m->private = cell;
return 0;
} /* end afs_proc_cell_vlservers_open() */
/*****************************************************************************/
/*
* close the file and release the ref to the cell
*/
static int afs_proc_cell_vlservers_release(struct inode *inode,
struct file *file)
{
struct afs_cell *cell = PDE(inode)->data;
int ret;
ret = seq_release(inode,file);
afs_put_cell(cell);
return ret;
} /* end afs_proc_cell_vlservers_release() */
/*****************************************************************************/
/*
* set up the iterator to start reading from the cells list and return the
* first item
*/
static void *afs_proc_cell_vlservers_start(struct seq_file *m, loff_t *_pos)
{
struct afs_cell *cell = m->private;
loff_t pos = *_pos;
_enter("cell=%p pos=%Ld", cell, *_pos);
/* lock the list against modification */
down_read(&cell->vl_sem);
/* allow for the header line */
if (!pos)
return (void *) 1;
pos--;
if (pos >= cell->vl_naddrs)
return NULL;
return &cell->vl_addrs[pos];
} /* end afs_proc_cell_vlservers_start() */
/*****************************************************************************/
/*
* move to next cell in cells list
*/
static void *afs_proc_cell_vlservers_next(struct seq_file *p, void *v,
loff_t *_pos)
{
struct afs_cell *cell = p->private;
loff_t pos;
_enter("cell=%p{nad=%u} pos=%Ld", cell, cell->vl_naddrs, *_pos);
pos = *_pos;
(*_pos)++;
if (pos >= cell->vl_naddrs)
return NULL;
return &cell->vl_addrs[pos];
} /* end afs_proc_cell_vlservers_next() */
/*****************************************************************************/
/*
* clean up after reading from the cells list
*/
static void afs_proc_cell_vlservers_stop(struct seq_file *p, void *v)
{
struct afs_cell *cell = p->private;
up_read(&cell->vl_sem);
} /* end afs_proc_cell_vlservers_stop() */
/*****************************************************************************/
/*
* display a header line followed by a load of volume lines
*/
static int afs_proc_cell_vlservers_show(struct seq_file *m, void *v)
{
struct in_addr *addr = v;
/* display header on line 1 */
if (v == (struct in_addr *) 1) {
seq_puts(m, "ADDRESS\n");
return 0;
}
/* display one cell per line on subsequent lines */
seq_printf(m, "%u.%u.%u.%u\n", NIPQUAD(addr->s_addr));
return 0;
} /* end afs_proc_cell_vlservers_show() */
/*****************************************************************************/
/*
* open "/proc/fs/afs/<cell>/servers" which provides a summary of active
* servers
*/
static int afs_proc_cell_servers_open(struct inode *inode, struct file *file)
{
struct afs_cell *cell;
struct seq_file *m;
int ret;
cell = afs_get_cell_maybe((struct afs_cell **) &PDE(inode)->data);
if (!cell)
return -ENOENT;
ret = seq_open(file, &afs_proc_cell_servers_ops);
if (ret < 0)
return ret;
m = file->private_data;
m->private = cell;
return 0;
} /* end afs_proc_cell_servers_open() */
/*****************************************************************************/
/*
* close the file and release the ref to the cell
*/
static int afs_proc_cell_servers_release(struct inode *inode,
struct file *file)
{
struct afs_cell *cell = PDE(inode)->data;
int ret;
ret = seq_release(inode, file);
afs_put_cell(cell);
return ret;
} /* end afs_proc_cell_servers_release() */
/*****************************************************************************/
/*
* set up the iterator to start reading from the cells list and return the
* first item
*/
static void *afs_proc_cell_servers_start(struct seq_file *m, loff_t *_pos)
__acquires(m->private->sv_lock)
{
struct list_head *_p;
struct afs_cell *cell = m->private;
loff_t pos = *_pos;
_enter("cell=%p pos=%Ld", cell, *_pos);
/* lock the list against modification */
read_lock(&cell->sv_lock);
/* allow for the header line */
if (!pos)
return (void *) 1;
pos--;
/* find the n'th element in the list */
list_for_each(_p, &cell->sv_list)
if (!pos--)
break;
return _p != &cell->sv_list ? _p : NULL;
} /* end afs_proc_cell_servers_start() */
/*****************************************************************************/
/*
* move to next cell in cells list
*/
static void *afs_proc_cell_servers_next(struct seq_file *p, void *v,
loff_t *_pos)
{
struct list_head *_p;
struct afs_cell *cell = p->private;
_enter("cell=%p pos=%Ld", cell, *_pos);
(*_pos)++;
_p = v;
_p = v == (void *) 1 ? cell->sv_list.next : _p->next;
return _p != &cell->sv_list ? _p : NULL;
} /* end afs_proc_cell_servers_next() */
/*****************************************************************************/
/*
* clean up after reading from the cells list
*/
static void afs_proc_cell_servers_stop(struct seq_file *p, void *v)
__releases(p->private->sv_lock)
{
struct afs_cell *cell = p->private;
read_unlock(&cell->sv_lock);
} /* end afs_proc_cell_servers_stop() */
/*****************************************************************************/
/*
* display a header line followed by a load of volume lines
*/
static int afs_proc_cell_servers_show(struct seq_file *m, void *v)
{
struct afs_server *server = list_entry(v, struct afs_server, link);
char ipaddr[20];
/* display header on line 1 */
if (v == (void *) 1) {
seq_puts(m, "USE ADDR STATE\n");
return 0;
}
/* display one cell per line on subsequent lines */
sprintf(ipaddr, "%u.%u.%u.%u", NIPQUAD(server->addr));
seq_printf(m, "%3d %-15.15s %5d\n",
atomic_read(&server->usage),
ipaddr,
server->fs_state
);
return 0;
} /* end afs_proc_cell_servers_show() */