WSL2-Linux-Kernel/fs/afs/proc.c

707 строки
16 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/* /proc interface for AFS
*
* Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*/
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/sched.h>
#include <linux/uaccess.h>
#include "internal.h"
struct afs_vl_seq_net_private {
struct seq_net_private seq; /* Must be first */
struct afs_vlserver_list *vllist;
};
static inline struct afs_net *afs_seq2net(struct seq_file *m)
{
return afs_net(seq_file_net(m));
}
static inline struct afs_net *afs_seq2net_single(struct seq_file *m)
{
return afs_net(seq_file_single_net(m));
}
/*
* Display the list of cells known to the namespace.
*/
static int afs_proc_cells_show(struct seq_file *m, void *v)
{
struct afs_vlserver_list *vllist;
struct afs_cell *cell;
if (v == SEQ_START_TOKEN) {
/* display header on line 1 */
seq_puts(m, "USE TTL SV ST NAME\n");
return 0;
}
cell = list_entry(v, struct afs_cell, proc_link);
vllist = rcu_dereference(cell->vl_servers);
/* display one cell per line on subsequent lines */
seq_printf(m, "%3u %6lld %2u %2u %s\n",
atomic_read(&cell->usage),
cell->dns_expiry - ktime_get_real_seconds(),
vllist->nr_servers,
cell->state,
cell->name);
return 0;
}
static void *afs_proc_cells_start(struct seq_file *m, loff_t *_pos)
__acquires(rcu)
{
rcu_read_lock();
return seq_hlist_start_head_rcu(&afs_seq2net(m)->proc_cells, *_pos);
}
static void *afs_proc_cells_next(struct seq_file *m, void *v, loff_t *pos)
{
return seq_hlist_next_rcu(v, &afs_seq2net(m)->proc_cells, pos);
}
static void afs_proc_cells_stop(struct seq_file *m, void *v)
__releases(rcu)
{
rcu_read_unlock();
}
static const 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,
};
/*
* handle writes to /proc/fs/afs/cells
* - to add cells: echo "add <cellname> <IP>[:<IP>][:<IP>]"
*/
static int afs_proc_cells_write(struct file *file, char *buf, size_t size)
{
struct seq_file *m = file->private_data;
struct afs_net *net = afs_seq2net(m);
char *name, *args;
int ret;
/* trim to first NL */
name = memchr(buf, '\n', size);
if (name)
*name = 0;
/* split into command, name and argslist */
name = strchr(buf, ' ');
if (!name)
goto inval;
do {
*name++ = 0;
} while(*name == ' ');
if (!*name)
goto inval;
args = strchr(name, ' ');
if (args) {
do {
*args++ = 0;
} while(*args == ' ');
if (!*args)
goto inval;
}
/* determine command to perform */
_debug("cmd=%s name=%s args=%s", buf, name, args);
if (strcmp(buf, "add") == 0) {
struct afs_cell *cell;
cell = afs_lookup_cell(net, name, strlen(name), args, true);
if (IS_ERR(cell)) {
ret = PTR_ERR(cell);
goto done;
}
if (test_and_set_bit(AFS_CELL_FL_NO_GC, &cell->flags))
afs_put_cell(net, cell);
} else {
goto inval;
}
ret = 0;
done:
_leave(" = %d", ret);
return ret;
inval:
ret = -EINVAL;
printk("kAFS: Invalid Command on /proc/fs/afs/cells file\n");
goto done;
}
/*
* Display the name of the current workstation cell.
*/
static int afs_proc_rootcell_show(struct seq_file *m, void *v)
{
struct afs_cell *cell;
struct afs_net *net;
net = afs_seq2net_single(m);
if (rcu_access_pointer(net->ws_cell)) {
rcu_read_lock();
cell = rcu_dereference(net->ws_cell);
if (cell)
seq_printf(m, "%s\n", cell->name);
rcu_read_unlock();
}
return 0;
}
/*
* Set the current workstation cell and optionally supply its list of volume
* location servers.
*
* echo "cell.name:192.168.231.14" >/proc/fs/afs/rootcell
*/
static int afs_proc_rootcell_write(struct file *file, char *buf, size_t size)
{
struct seq_file *m = file->private_data;
struct afs_net *net = afs_seq2net_single(m);
char *s;
int ret;
ret = -EINVAL;
if (buf[0] == '.')
goto out;
if (memchr(buf, '/', size))
goto out;
/* trim to first NL */
s = memchr(buf, '\n', size);
if (s)
*s = 0;
/* determine command to perform */
_debug("rootcell=%s", buf);
ret = afs_cell_init(net, buf);
out:
_leave(" = %d", ret);
return ret;
}
static const char afs_vol_types[3][3] = {
[AFSVL_RWVOL] = "RW",
[AFSVL_ROVOL] = "RO",
[AFSVL_BACKVOL] = "BK",
};
/*
* Display the list of volumes known to a cell.
*/
static int afs_proc_cell_volumes_show(struct seq_file *m, void *v)
{
struct afs_volume *vol = hlist_entry(v, struct afs_volume, proc_link);
/* Display header on line 1 */
if (v == SEQ_START_TOKEN) {
seq_puts(m, "USE VID TY NAME\n");
return 0;
}
seq_printf(m, "%3d %08llx %s %s\n",
atomic_read(&vol->usage), vol->vid,
afs_vol_types[vol->type],
vol->name);
return 0;
}
static void *afs_proc_cell_volumes_start(struct seq_file *m, loff_t *_pos)
__acquires(cell->proc_lock)
{
struct afs_cell *cell = PDE_DATA(file_inode(m->file));
rcu_read_lock();
return seq_hlist_start_head_rcu(&cell->proc_volumes, *_pos);
}
static void *afs_proc_cell_volumes_next(struct seq_file *m, void *v,
loff_t *_pos)
{
struct afs_cell *cell = PDE_DATA(file_inode(m->file));
return seq_hlist_next_rcu(v, &cell->proc_volumes, _pos);
}
static void afs_proc_cell_volumes_stop(struct seq_file *m, void *v)
__releases(cell->proc_lock)
{
rcu_read_unlock();
}
static const 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 char *const dns_record_sources[NR__dns_record_source + 1] = {
[DNS_RECORD_UNAVAILABLE] = "unav",
[DNS_RECORD_FROM_CONFIG] = "cfg",
[DNS_RECORD_FROM_DNS_A] = "A",
[DNS_RECORD_FROM_DNS_AFSDB] = "AFSDB",
[DNS_RECORD_FROM_DNS_SRV] = "SRV",
[DNS_RECORD_FROM_NSS] = "nss",
[NR__dns_record_source] = "[weird]"
};
static const char *const dns_lookup_statuses[NR__dns_lookup_status + 1] = {
[DNS_LOOKUP_NOT_DONE] = "no-lookup",
[DNS_LOOKUP_GOOD] = "good",
[DNS_LOOKUP_GOOD_WITH_BAD] = "good/bad",
[DNS_LOOKUP_BAD] = "bad",
[DNS_LOOKUP_GOT_NOT_FOUND] = "not-found",
[DNS_LOOKUP_GOT_LOCAL_FAILURE] = "local-failure",
[DNS_LOOKUP_GOT_TEMP_FAILURE] = "temp-failure",
[DNS_LOOKUP_GOT_NS_FAILURE] = "ns-failure",
[NR__dns_lookup_status] = "[weird]"
};
/*
* Display the list of Volume Location servers we're using for a cell.
*/
static int afs_proc_cell_vlservers_show(struct seq_file *m, void *v)
{
const struct afs_vl_seq_net_private *priv = m->private;
const struct afs_vlserver_list *vllist = priv->vllist;
const struct afs_vlserver_entry *entry;
const struct afs_vlserver *vlserver;
const struct afs_addr_list *alist;
int i;
if (v == SEQ_START_TOKEN) {
seq_printf(m, "# source %s, status %s\n",
dns_record_sources[vllist ? vllist->source : 0],
dns_lookup_statuses[vllist ? vllist->status : 0]);
return 0;
}
entry = v;
vlserver = entry->server;
alist = rcu_dereference(vlserver->addresses);
seq_printf(m, "%s [p=%hu w=%hu s=%s,%s]:\n",
vlserver->name, entry->priority, entry->weight,
dns_record_sources[alist ? alist->source : entry->source],
dns_lookup_statuses[alist ? alist->status : entry->status]);
if (alist) {
for (i = 0; i < alist->nr_addrs; i++)
seq_printf(m, " %c %pISpc\n",
alist->preferred == i ? '>' : '-',
&alist->addrs[i].transport);
}
seq_printf(m, " info: fl=%lx rtt=%d\n", vlserver->flags, vlserver->rtt);
seq_printf(m, " probe: fl=%x e=%d ac=%d out=%d\n",
vlserver->probe.flags, vlserver->probe.error,
vlserver->probe.abort_code,
atomic_read(&vlserver->probe_outstanding));
return 0;
}
static void *afs_proc_cell_vlservers_start(struct seq_file *m, loff_t *_pos)
__acquires(rcu)
{
struct afs_vl_seq_net_private *priv = m->private;
struct afs_vlserver_list *vllist;
struct afs_cell *cell = PDE_DATA(file_inode(m->file));
loff_t pos = *_pos;
rcu_read_lock();
vllist = rcu_dereference(cell->vl_servers);
priv->vllist = vllist;
if (pos < 0)
*_pos = pos = 0;
if (pos == 0)
return SEQ_START_TOKEN;
if (pos - 1 >= vllist->nr_servers)
return NULL;
return &vllist->servers[pos - 1];
}
static void *afs_proc_cell_vlservers_next(struct seq_file *m, void *v,
loff_t *_pos)
{
struct afs_vl_seq_net_private *priv = m->private;
struct afs_vlserver_list *vllist = priv->vllist;
loff_t pos;
pos = *_pos;
pos++;
*_pos = pos;
if (!vllist || pos - 1 >= vllist->nr_servers)
return NULL;
return &vllist->servers[pos - 1];
}
static void afs_proc_cell_vlservers_stop(struct seq_file *m, void *v)
__releases(rcu)
{
rcu_read_unlock();
}
static const 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,
};
/*
* Display the list of fileservers we're using within a namespace.
*/
static int afs_proc_servers_show(struct seq_file *m, void *v)
{
struct afs_server *server;
struct afs_addr_list *alist;
int i;
if (v == SEQ_START_TOKEN) {
seq_puts(m, "UUID REF ACT\n");
return 0;
}
server = list_entry(v, struct afs_server, proc_link);
alist = rcu_dereference(server->addresses);
seq_printf(m, "%pU %3d %3d\n",
&server->uuid,
atomic_read(&server->ref),
atomic_read(&server->active));
seq_printf(m, " - info: fl=%lx rtt=%u brk=%x\n",
server->flags, server->rtt, server->cb_s_break);
seq_printf(m, " - probe: last=%d out=%d\n",
(int)(jiffies - server->probed_at) / HZ,
atomic_read(&server->probe_outstanding));
seq_printf(m, " - ALIST v=%u rsp=%lx f=%lx\n",
alist->version, alist->responded, alist->failed);
for (i = 0; i < alist->nr_addrs; i++)
seq_printf(m, " [%x] %pISpc%s\n",
i, &alist->addrs[i].transport,
alist->preferred == i ? "*" : "");
return 0;
}
static void *afs_proc_servers_start(struct seq_file *m, loff_t *_pos)
__acquires(rcu)
{
rcu_read_lock();
return seq_hlist_start_head_rcu(&afs_seq2net(m)->fs_proc, *_pos);
}
static void *afs_proc_servers_next(struct seq_file *m, void *v, loff_t *_pos)
{
return seq_hlist_next_rcu(v, &afs_seq2net(m)->fs_proc, _pos);
}
static void afs_proc_servers_stop(struct seq_file *m, void *v)
__releases(rcu)
{
rcu_read_unlock();
}
static const struct seq_operations afs_proc_servers_ops = {
.start = afs_proc_servers_start,
.next = afs_proc_servers_next,
.stop = afs_proc_servers_stop,
.show = afs_proc_servers_show,
};
/*
* Display the list of strings that may be substituted for the @sys pathname
* macro.
*/
static int afs_proc_sysname_show(struct seq_file *m, void *v)
{
struct afs_net *net = afs_seq2net(m);
struct afs_sysnames *sysnames = net->sysnames;
unsigned int i = (unsigned long)v - 1;
if (i < sysnames->nr)
seq_printf(m, "%s\n", sysnames->subs[i]);
return 0;
}
static void *afs_proc_sysname_start(struct seq_file *m, loff_t *pos)
__acquires(&net->sysnames_lock)
{
struct afs_net *net = afs_seq2net(m);
struct afs_sysnames *names;
read_lock(&net->sysnames_lock);
names = net->sysnames;
if (*pos >= names->nr)
return NULL;
return (void *)(unsigned long)(*pos + 1);
}
static void *afs_proc_sysname_next(struct seq_file *m, void *v, loff_t *pos)
{
struct afs_net *net = afs_seq2net(m);
struct afs_sysnames *names = net->sysnames;
*pos += 1;
if (*pos >= names->nr)
return NULL;
return (void *)(unsigned long)(*pos + 1);
}
static void afs_proc_sysname_stop(struct seq_file *m, void *v)
__releases(&net->sysnames_lock)
{
struct afs_net *net = afs_seq2net(m);
read_unlock(&net->sysnames_lock);
}
static const struct seq_operations afs_proc_sysname_ops = {
.start = afs_proc_sysname_start,
.next = afs_proc_sysname_next,
.stop = afs_proc_sysname_stop,
.show = afs_proc_sysname_show,
};
/*
* Allow the @sys substitution to be configured.
*/
static int afs_proc_sysname_write(struct file *file, char *buf, size_t size)
{
struct afs_sysnames *sysnames, *kill;
struct seq_file *m = file->private_data;
struct afs_net *net = afs_seq2net(m);
char *s, *p, *sub;
int ret, len;
sysnames = kzalloc(sizeof(*sysnames), GFP_KERNEL);
if (!sysnames)
return -ENOMEM;
refcount_set(&sysnames->usage, 1);
kill = sysnames;
p = buf;
while ((s = strsep(&p, " \t\n"))) {
len = strlen(s);
if (len == 0)
continue;
ret = -ENAMETOOLONG;
if (len >= AFSNAMEMAX)
goto error;
if (len >= 4 &&
s[len - 4] == '@' &&
s[len - 3] == 's' &&
s[len - 2] == 'y' &&
s[len - 1] == 's')
/* Protect against recursion */
goto invalid;
if (s[0] == '.' &&
(len < 2 || (len == 2 && s[1] == '.')))
goto invalid;
if (memchr(s, '/', len))
goto invalid;
ret = -EFBIG;
if (sysnames->nr >= AFS_NR_SYSNAME)
goto out;
if (strcmp(s, afs_init_sysname) == 0) {
sub = (char *)afs_init_sysname;
} else {
ret = -ENOMEM;
sub = kmemdup(s, len + 1, GFP_KERNEL);
if (!sub)
goto out;
}
sysnames->subs[sysnames->nr] = sub;
sysnames->nr++;
}
if (sysnames->nr == 0) {
sysnames->subs[0] = sysnames->blank;
sysnames->nr++;
}
write_lock(&net->sysnames_lock);
kill = net->sysnames;
net->sysnames = sysnames;
write_unlock(&net->sysnames_lock);
ret = 0;
out:
afs_put_sysnames(kill);
return ret;
invalid:
ret = -EINVAL;
error:
goto out;
}
void afs_put_sysnames(struct afs_sysnames *sysnames)
{
int i;
if (sysnames && refcount_dec_and_test(&sysnames->usage)) {
for (i = 0; i < sysnames->nr; i++)
if (sysnames->subs[i] != afs_init_sysname &&
sysnames->subs[i] != sysnames->blank)
kfree(sysnames->subs[i]);
kfree(sysnames);
}
}
/*
* Display general per-net namespace statistics
*/
static int afs_proc_stats_show(struct seq_file *m, void *v)
{
struct afs_net *net = afs_seq2net_single(m);
seq_puts(m, "kAFS statistics\n");
seq_printf(m, "dir-mgmt: look=%u reval=%u inval=%u relpg=%u\n",
atomic_read(&net->n_lookup),
atomic_read(&net->n_reval),
atomic_read(&net->n_inval),
atomic_read(&net->n_relpg));
seq_printf(m, "dir-data: rdpg=%u\n",
atomic_read(&net->n_read_dir));
seq_printf(m, "dir-edit: cr=%u rm=%u\n",
atomic_read(&net->n_dir_cr),
atomic_read(&net->n_dir_rm));
seq_printf(m, "file-rd : n=%u nb=%lu\n",
atomic_read(&net->n_fetches),
atomic_long_read(&net->n_fetch_bytes));
seq_printf(m, "file-wr : n=%u nb=%lu\n",
atomic_read(&net->n_stores),
atomic_long_read(&net->n_store_bytes));
return 0;
}
/*
* initialise /proc/fs/afs/<cell>/
*/
int afs_proc_cell_setup(struct afs_cell *cell)
{
struct proc_dir_entry *dir;
struct afs_net *net = cell->net;
_enter("%p{%s},%p", cell, cell->name, net->proc_afs);
dir = proc_net_mkdir(net->net, cell->name, net->proc_afs);
if (!dir)
goto error_dir;
if (!proc_create_net_data("vlservers", 0444, dir,
&afs_proc_cell_vlservers_ops,
sizeof(struct afs_vl_seq_net_private),
cell) ||
!proc_create_net_data("volumes", 0444, dir,
&afs_proc_cell_volumes_ops,
sizeof(struct seq_net_private),
cell))
goto error_tree;
_leave(" = 0");
return 0;
error_tree:
remove_proc_subtree(cell->name, net->proc_afs);
error_dir:
_leave(" = -ENOMEM");
return -ENOMEM;
}
/*
* remove /proc/fs/afs/<cell>/
*/
void afs_proc_cell_remove(struct afs_cell *cell)
{
struct afs_net *net = cell->net;
_enter("");
remove_proc_subtree(cell->name, net->proc_afs);
_leave("");
}
/*
* initialise the /proc/fs/afs/ directory
*/
int afs_proc_init(struct afs_net *net)
{
struct proc_dir_entry *p;
_enter("");
p = proc_net_mkdir(net->net, "afs", net->net->proc_net);
if (!p)
goto error_dir;
if (!proc_create_net_data_write("cells", 0644, p,
&afs_proc_cells_ops,
afs_proc_cells_write,
sizeof(struct seq_net_private),
NULL) ||
!proc_create_net_single_write("rootcell", 0644, p,
afs_proc_rootcell_show,
afs_proc_rootcell_write,
NULL) ||
!proc_create_net("servers", 0444, p, &afs_proc_servers_ops,
sizeof(struct seq_net_private)) ||
!proc_create_net_single("stats", 0444, p, afs_proc_stats_show, NULL) ||
!proc_create_net_data_write("sysname", 0644, p,
&afs_proc_sysname_ops,
afs_proc_sysname_write,
sizeof(struct seq_net_private),
NULL))
goto error_tree;
net->proc_afs = p;
_leave(" = 0");
return 0;
error_tree:
proc_remove(p);
error_dir:
_leave(" = -ENOMEM");
return -ENOMEM;
}
/*
* clean up the /proc/fs/afs/ directory
*/
void afs_proc_cleanup(struct afs_net *net)
{
proc_remove(net->proc_afs);
net->proc_afs = NULL;
}