linux_dsm_epyc7002/fs/quota/quota.c
Christoph Hellwig a56fca23f6 quota: remove invalid optimization from quota_sync_all
Checking the "VFS" quota enabled and dirty bits from generic code means
this code will never get called for other implementations, e.g. XFS and
GFS2.  Grabbing the reference on the superblock really isn't much overhead
for a global Q_SYNC call, so just drop this optimization.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
2010-03-05 00:20:24 +01:00

552 lines
14 KiB
C

/*
* Quota code necessary even when VFS quota support is not compiled
* into the kernel. The interesting stuff is over in dquot.c, here
* we have symbols for initial quotactl(2) handling, the sysctl(2)
* variables, etc - things needed even when quota support disabled.
*/
#include <linux/fs.h>
#include <linux/namei.h>
#include <linux/slab.h>
#include <asm/current.h>
#include <asm/uaccess.h>
#include <linux/compat.h>
#include <linux/kernel.h>
#include <linux/security.h>
#include <linux/syscalls.h>
#include <linux/buffer_head.h>
#include <linux/capability.h>
#include <linux/quotaops.h>
#include <linux/types.h>
#include <linux/writeback.h>
#include <net/netlink.h>
#include <net/genetlink.h>
static int check_quotactl_permission(struct super_block *sb, int type, int cmd,
qid_t id)
{
switch (cmd) {
/* these commands do not require any special privilegues */
case Q_GETFMT:
case Q_SYNC:
case Q_GETINFO:
case Q_XGETQSTAT:
case Q_XQUOTASYNC:
break;
/* allow to query information for dquots we "own" */
case Q_GETQUOTA:
case Q_XGETQUOTA:
if ((type == USRQUOTA && current_euid() == id) ||
(type == GRPQUOTA && in_egroup_p(id)))
break;
/*FALLTHROUGH*/
default:
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
}
return security_quotactl(cmd, type, id, sb);
}
static int quota_sync_all(int type)
{
struct super_block *sb;
int ret;
if (type >= MAXQUOTAS)
return -EINVAL;
ret = security_quotactl(Q_SYNC, type, 0, NULL);
if (ret)
return ret;
spin_lock(&sb_lock);
restart:
list_for_each_entry(sb, &super_blocks, s_list) {
if (!sb->s_qcop || !sb->s_qcop->quota_sync)
continue;
sb->s_count++;
spin_unlock(&sb_lock);
down_read(&sb->s_umount);
if (sb->s_root)
sb->s_qcop->quota_sync(sb, type, 1);
up_read(&sb->s_umount);
spin_lock(&sb_lock);
if (__put_super_and_need_restart(sb))
goto restart;
}
spin_unlock(&sb_lock);
return 0;
}
static int quota_quotaon(struct super_block *sb, int type, int cmd, qid_t id,
void __user *addr)
{
char *pathname;
int ret = -ENOSYS;
pathname = getname(addr);
if (IS_ERR(pathname))
return PTR_ERR(pathname);
if (sb->s_qcop->quota_on)
ret = sb->s_qcop->quota_on(sb, type, id, pathname, 0);
putname(pathname);
return ret;
}
static int quota_getfmt(struct super_block *sb, int type, void __user *addr)
{
__u32 fmt;
down_read(&sb_dqopt(sb)->dqptr_sem);
if (!sb_has_quota_active(sb, type)) {
up_read(&sb_dqopt(sb)->dqptr_sem);
return -ESRCH;
}
fmt = sb_dqopt(sb)->info[type].dqi_format->qf_fmt_id;
up_read(&sb_dqopt(sb)->dqptr_sem);
if (copy_to_user(addr, &fmt, sizeof(fmt)))
return -EFAULT;
return 0;
}
static int quota_getinfo(struct super_block *sb, int type, void __user *addr)
{
struct if_dqinfo info;
int ret;
if (!sb_has_quota_active(sb, type))
return -ESRCH;
if (!sb->s_qcop->get_info)
return -ENOSYS;
ret = sb->s_qcop->get_info(sb, type, &info);
if (!ret && copy_to_user(addr, &info, sizeof(info)))
return -EFAULT;
return ret;
}
static int quota_setinfo(struct super_block *sb, int type, void __user *addr)
{
struct if_dqinfo info;
if (copy_from_user(&info, addr, sizeof(info)))
return -EFAULT;
if (!sb_has_quota_active(sb, type))
return -ESRCH;
if (!sb->s_qcop->set_info)
return -ENOSYS;
return sb->s_qcop->set_info(sb, type, &info);
}
static int quota_getquota(struct super_block *sb, int type, qid_t id,
void __user *addr)
{
struct if_dqblk idq;
int ret;
if (!sb_has_quota_active(sb, type))
return -ESRCH;
if (!sb->s_qcop->get_dqblk)
return -ENOSYS;
ret = sb->s_qcop->get_dqblk(sb, type, id, &idq);
if (ret)
return ret;
if (copy_to_user(addr, &idq, sizeof(idq)))
return -EFAULT;
return 0;
}
static int quota_setquota(struct super_block *sb, int type, qid_t id,
void __user *addr)
{
struct if_dqblk idq;
if (copy_from_user(&idq, addr, sizeof(idq)))
return -EFAULT;
if (!sb_has_quota_active(sb, type))
return -ESRCH;
if (!sb->s_qcop->set_dqblk)
return -ENOSYS;
return sb->s_qcop->set_dqblk(sb, type, id, &idq);
}
static int quota_setxstate(struct super_block *sb, int cmd, void __user *addr)
{
__u32 flags;
if (copy_from_user(&flags, addr, sizeof(flags)))
return -EFAULT;
if (!sb->s_qcop->set_xstate)
return -ENOSYS;
return sb->s_qcop->set_xstate(sb, flags, cmd);
}
static int quota_getxstate(struct super_block *sb, void __user *addr)
{
struct fs_quota_stat fqs;
int ret;
if (!sb->s_qcop->get_xstate)
return -ENOSYS;
ret = sb->s_qcop->get_xstate(sb, &fqs);
if (!ret && copy_to_user(addr, &fqs, sizeof(fqs)))
return -EFAULT;
return ret;
}
static int quota_setxquota(struct super_block *sb, int type, qid_t id,
void __user *addr)
{
struct fs_disk_quota fdq;
if (copy_from_user(&fdq, addr, sizeof(fdq)))
return -EFAULT;
if (!sb->s_qcop->set_xquota)
return -ENOSYS;
return sb->s_qcop->set_xquota(sb, type, id, &fdq);
}
static int quota_getxquota(struct super_block *sb, int type, qid_t id,
void __user *addr)
{
struct fs_disk_quota fdq;
int ret;
if (!sb->s_qcop->get_xquota)
return -ENOSYS;
ret = sb->s_qcop->get_xquota(sb, type, id, &fdq);
if (!ret && copy_to_user(addr, &fdq, sizeof(fdq)))
return -EFAULT;
return ret;
}
/* Copy parameters and call proper function */
static int do_quotactl(struct super_block *sb, int type, int cmd, qid_t id,
void __user *addr)
{
int ret;
if (type >= (XQM_COMMAND(cmd) ? XQM_MAXQUOTAS : MAXQUOTAS))
return -EINVAL;
if (!sb->s_qcop)
return -ENOSYS;
ret = check_quotactl_permission(sb, type, cmd, id);
if (ret < 0)
return ret;
switch (cmd) {
case Q_QUOTAON:
return quota_quotaon(sb, type, cmd, id, addr);
case Q_QUOTAOFF:
if (!sb->s_qcop->quota_off)
return -ENOSYS;
return sb->s_qcop->quota_off(sb, type, 0);
case Q_GETFMT:
return quota_getfmt(sb, type, addr);
case Q_GETINFO:
return quota_getinfo(sb, type, addr);
case Q_SETINFO:
return quota_setinfo(sb, type, addr);
case Q_GETQUOTA:
return quota_getquota(sb, type, id, addr);
case Q_SETQUOTA:
return quota_setquota(sb, type, id, addr);
case Q_SYNC:
if (!sb->s_qcop->quota_sync)
return -ENOSYS;
return sb->s_qcop->quota_sync(sb, type, 1);
case Q_XQUOTAON:
case Q_XQUOTAOFF:
case Q_XQUOTARM:
return quota_setxstate(sb, cmd, addr);
case Q_XGETQSTAT:
return quota_getxstate(sb, addr);
case Q_XSETQLIM:
return quota_setxquota(sb, type, id, addr);
case Q_XGETQUOTA:
return quota_getxquota(sb, type, id, addr);
case Q_XQUOTASYNC:
/* caller already holds s_umount */
if (sb->s_flags & MS_RDONLY)
return -EROFS;
writeback_inodes_sb(sb);
return 0;
default:
return -EINVAL;
}
}
/*
* look up a superblock on which quota ops will be performed
* - use the name of a block device to find the superblock thereon
*/
static struct super_block *quotactl_block(const char __user *special)
{
#ifdef CONFIG_BLOCK
struct block_device *bdev;
struct super_block *sb;
char *tmp = getname(special);
if (IS_ERR(tmp))
return ERR_CAST(tmp);
bdev = lookup_bdev(tmp);
putname(tmp);
if (IS_ERR(bdev))
return ERR_CAST(bdev);
sb = get_super(bdev);
bdput(bdev);
if (!sb)
return ERR_PTR(-ENODEV);
return sb;
#else
return ERR_PTR(-ENODEV);
#endif
}
/*
* This is the system call interface. This communicates with
* the user-level programs. Currently this only supports diskquota
* calls. Maybe we need to add the process quotas etc. in the future,
* but we probably should use rlimits for that.
*/
SYSCALL_DEFINE4(quotactl, unsigned int, cmd, const char __user *, special,
qid_t, id, void __user *, addr)
{
uint cmds, type;
struct super_block *sb = NULL;
int ret;
cmds = cmd >> SUBCMDSHIFT;
type = cmd & SUBCMDMASK;
/*
* As a special case Q_SYNC can be called without a specific device.
* It will iterate all superblocks that have quota enabled and call
* the sync action on each of them.
*/
if (!special) {
if (cmds == Q_SYNC)
return quota_sync_all(type);
return -ENODEV;
}
sb = quotactl_block(special);
if (IS_ERR(sb))
return PTR_ERR(sb);
ret = do_quotactl(sb, type, cmds, id, addr);
drop_super(sb);
return ret;
}
#if defined(CONFIG_COMPAT_FOR_U64_ALIGNMENT)
/*
* This code works only for 32 bit quota tools over 64 bit OS (x86_64, ia64)
* and is necessary due to alignment problems.
*/
struct compat_if_dqblk {
compat_u64 dqb_bhardlimit;
compat_u64 dqb_bsoftlimit;
compat_u64 dqb_curspace;
compat_u64 dqb_ihardlimit;
compat_u64 dqb_isoftlimit;
compat_u64 dqb_curinodes;
compat_u64 dqb_btime;
compat_u64 dqb_itime;
compat_uint_t dqb_valid;
};
/* XFS structures */
struct compat_fs_qfilestat {
compat_u64 dqb_bhardlimit;
compat_u64 qfs_nblks;
compat_uint_t qfs_nextents;
};
struct compat_fs_quota_stat {
__s8 qs_version;
__u16 qs_flags;
__s8 qs_pad;
struct compat_fs_qfilestat qs_uquota;
struct compat_fs_qfilestat qs_gquota;
compat_uint_t qs_incoredqs;
compat_int_t qs_btimelimit;
compat_int_t qs_itimelimit;
compat_int_t qs_rtbtimelimit;
__u16 qs_bwarnlimit;
__u16 qs_iwarnlimit;
};
asmlinkage long sys32_quotactl(unsigned int cmd, const char __user *special,
qid_t id, void __user *addr)
{
unsigned int cmds;
struct if_dqblk __user *dqblk;
struct compat_if_dqblk __user *compat_dqblk;
struct fs_quota_stat __user *fsqstat;
struct compat_fs_quota_stat __user *compat_fsqstat;
compat_uint_t data;
u16 xdata;
long ret;
cmds = cmd >> SUBCMDSHIFT;
switch (cmds) {
case Q_GETQUOTA:
dqblk = compat_alloc_user_space(sizeof(struct if_dqblk));
compat_dqblk = addr;
ret = sys_quotactl(cmd, special, id, dqblk);
if (ret)
break;
if (copy_in_user(compat_dqblk, dqblk, sizeof(*compat_dqblk)) ||
get_user(data, &dqblk->dqb_valid) ||
put_user(data, &compat_dqblk->dqb_valid))
ret = -EFAULT;
break;
case Q_SETQUOTA:
dqblk = compat_alloc_user_space(sizeof(struct if_dqblk));
compat_dqblk = addr;
ret = -EFAULT;
if (copy_in_user(dqblk, compat_dqblk, sizeof(*compat_dqblk)) ||
get_user(data, &compat_dqblk->dqb_valid) ||
put_user(data, &dqblk->dqb_valid))
break;
ret = sys_quotactl(cmd, special, id, dqblk);
break;
case Q_XGETQSTAT:
fsqstat = compat_alloc_user_space(sizeof(struct fs_quota_stat));
compat_fsqstat = addr;
ret = sys_quotactl(cmd, special, id, fsqstat);
if (ret)
break;
ret = -EFAULT;
/* Copying qs_version, qs_flags, qs_pad */
if (copy_in_user(compat_fsqstat, fsqstat,
offsetof(struct compat_fs_quota_stat, qs_uquota)))
break;
/* Copying qs_uquota */
if (copy_in_user(&compat_fsqstat->qs_uquota,
&fsqstat->qs_uquota,
sizeof(compat_fsqstat->qs_uquota)) ||
get_user(data, &fsqstat->qs_uquota.qfs_nextents) ||
put_user(data, &compat_fsqstat->qs_uquota.qfs_nextents))
break;
/* Copying qs_gquota */
if (copy_in_user(&compat_fsqstat->qs_gquota,
&fsqstat->qs_gquota,
sizeof(compat_fsqstat->qs_gquota)) ||
get_user(data, &fsqstat->qs_gquota.qfs_nextents) ||
put_user(data, &compat_fsqstat->qs_gquota.qfs_nextents))
break;
/* Copying the rest */
if (copy_in_user(&compat_fsqstat->qs_incoredqs,
&fsqstat->qs_incoredqs,
sizeof(struct compat_fs_quota_stat) -
offsetof(struct compat_fs_quota_stat, qs_incoredqs)) ||
get_user(xdata, &fsqstat->qs_iwarnlimit) ||
put_user(xdata, &compat_fsqstat->qs_iwarnlimit))
break;
ret = 0;
break;
default:
ret = sys_quotactl(cmd, special, id, addr);
}
return ret;
}
#endif
#ifdef CONFIG_QUOTA_NETLINK_INTERFACE
/* Netlink family structure for quota */
static struct genl_family quota_genl_family = {
.id = GENL_ID_GENERATE,
.hdrsize = 0,
.name = "VFS_DQUOT",
.version = 1,
.maxattr = QUOTA_NL_A_MAX,
};
/**
* quota_send_warning - Send warning to userspace about exceeded quota
* @type: The quota type: USRQQUOTA, GRPQUOTA,...
* @id: The user or group id of the quota that was exceeded
* @dev: The device on which the fs is mounted (sb->s_dev)
* @warntype: The type of the warning: QUOTA_NL_...
*
* This can be used by filesystems (including those which don't use
* dquot) to send a message to userspace relating to quota limits.
*
*/
void quota_send_warning(short type, unsigned int id, dev_t dev,
const char warntype)
{
static atomic_t seq;
struct sk_buff *skb;
void *msg_head;
int ret;
int msg_size = 4 * nla_total_size(sizeof(u32)) +
2 * nla_total_size(sizeof(u64));
/* We have to allocate using GFP_NOFS as we are called from a
* filesystem performing write and thus further recursion into
* the fs to free some data could cause deadlocks. */
skb = genlmsg_new(msg_size, GFP_NOFS);
if (!skb) {
printk(KERN_ERR
"VFS: Not enough memory to send quota warning.\n");
return;
}
msg_head = genlmsg_put(skb, 0, atomic_add_return(1, &seq),
&quota_genl_family, 0, QUOTA_NL_C_WARNING);
if (!msg_head) {
printk(KERN_ERR
"VFS: Cannot store netlink header in quota warning.\n");
goto err_out;
}
ret = nla_put_u32(skb, QUOTA_NL_A_QTYPE, type);
if (ret)
goto attr_err_out;
ret = nla_put_u64(skb, QUOTA_NL_A_EXCESS_ID, id);
if (ret)
goto attr_err_out;
ret = nla_put_u32(skb, QUOTA_NL_A_WARNING, warntype);
if (ret)
goto attr_err_out;
ret = nla_put_u32(skb, QUOTA_NL_A_DEV_MAJOR, MAJOR(dev));
if (ret)
goto attr_err_out;
ret = nla_put_u32(skb, QUOTA_NL_A_DEV_MINOR, MINOR(dev));
if (ret)
goto attr_err_out;
ret = nla_put_u64(skb, QUOTA_NL_A_CAUSED_ID, current_uid());
if (ret)
goto attr_err_out;
genlmsg_end(skb, msg_head);
genlmsg_multicast(skb, 0, quota_genl_family.id, GFP_NOFS);
return;
attr_err_out:
printk(KERN_ERR "VFS: Not enough space to compose quota message!\n");
err_out:
kfree_skb(skb);
}
EXPORT_SYMBOL(quota_send_warning);
static int __init quota_init(void)
{
if (genl_register_family(&quota_genl_family) != 0)
printk(KERN_ERR
"VFS: Failed to create quota netlink interface.\n");
return 0;
};
module_init(quota_init);
#endif