--- /dev/null
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/quota.h>
+#include <linux/quotaops.h>
+#include <linux/dqblk_v1.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+
+#include <asm/byteorder.h>
+
+#include "quotaio_v1.h"
+
+MODULE_AUTHOR("Jan Kara");
+MODULE_DESCRIPTION("Old quota format support");
+MODULE_LICENSE("GPL");
+
+#define QUOTABLOCK_BITS 10
+#define QUOTABLOCK_SIZE (1 << QUOTABLOCK_BITS)
+
+static inline qsize_t v1_stoqb(qsize_t space)
+{
+ return (space + QUOTABLOCK_SIZE - 1) >> QUOTABLOCK_BITS;
+}
+
+static inline qsize_t v1_qbtos(qsize_t blocks)
+{
+ return blocks << QUOTABLOCK_BITS;
+}
+
+static void v1_disk2mem_dqblk(struct mem_dqblk *m, struct v1_disk_dqblk *d)
+{
+ m->dqb_ihardlimit = d->dqb_ihardlimit;
+ m->dqb_isoftlimit = d->dqb_isoftlimit;
+ m->dqb_curinodes = d->dqb_curinodes;
+ m->dqb_bhardlimit = v1_qbtos(d->dqb_bhardlimit);
+ m->dqb_bsoftlimit = v1_qbtos(d->dqb_bsoftlimit);
+ m->dqb_curspace = v1_qbtos(d->dqb_curblocks);
+ m->dqb_itime = d->dqb_itime;
+ m->dqb_btime = d->dqb_btime;
+}
+
+static void v1_mem2disk_dqblk(struct v1_disk_dqblk *d, struct mem_dqblk *m)
+{
+ d->dqb_ihardlimit = m->dqb_ihardlimit;
+ d->dqb_isoftlimit = m->dqb_isoftlimit;
+ d->dqb_curinodes = m->dqb_curinodes;
+ d->dqb_bhardlimit = v1_stoqb(m->dqb_bhardlimit);
+ d->dqb_bsoftlimit = v1_stoqb(m->dqb_bsoftlimit);
+ d->dqb_curblocks = v1_stoqb(m->dqb_curspace);
+ d->dqb_itime = m->dqb_itime;
+ d->dqb_btime = m->dqb_btime;
+}
+
+static int v1_read_dqblk(struct dquot *dquot)
+{
+ int type = dquot->dq_id.type;
+ struct v1_disk_dqblk dqblk;
+
+ if (!sb_dqopt(dquot->dq_sb)->files[type])
+ return -EINVAL;
+
+ /* Set structure to 0s in case read fails/is after end of file */
+ memset(&dqblk, 0, sizeof(struct v1_disk_dqblk));
+ dquot->dq_sb->s_op->quota_read(dquot->dq_sb, type, (char *)&dqblk,
+ sizeof(struct v1_disk_dqblk),
+ v1_dqoff(from_kqid(&init_user_ns, dquot->dq_id)));
+
+ v1_disk2mem_dqblk(&dquot->dq_dqb, &dqblk);
+ if (dquot->dq_dqb.dqb_bhardlimit == 0 &&
+ dquot->dq_dqb.dqb_bsoftlimit == 0 &&
+ dquot->dq_dqb.dqb_ihardlimit == 0 &&
+ dquot->dq_dqb.dqb_isoftlimit == 0)
+ set_bit(DQ_FAKE_B, &dquot->dq_flags);
+ dqstats_inc(DQST_READS);
+
+ return 0;
+}
+
+static int v1_commit_dqblk(struct dquot *dquot)
+{
+ short type = dquot->dq_id.type;
+ ssize_t ret;
+ struct v1_disk_dqblk dqblk;
+
+ v1_mem2disk_dqblk(&dqblk, &dquot->dq_dqb);
+ if (((type == USRQUOTA) && uid_eq(dquot->dq_id.uid, GLOBAL_ROOT_UID)) ||
+ ((type == GRPQUOTA) && gid_eq(dquot->dq_id.gid, GLOBAL_ROOT_GID))) {
+ dqblk.dqb_btime =
+ sb_dqopt(dquot->dq_sb)->info[type].dqi_bgrace;
+ dqblk.dqb_itime =
+ sb_dqopt(dquot->dq_sb)->info[type].dqi_igrace;
+ }
+ ret = 0;
+ if (sb_dqopt(dquot->dq_sb)->files[type])
+ ret = dquot->dq_sb->s_op->quota_write(dquot->dq_sb, type,
+ (char *)&dqblk, sizeof(struct v1_disk_dqblk),
+ v1_dqoff(from_kqid(&init_user_ns, dquot->dq_id)));
+ if (ret != sizeof(struct v1_disk_dqblk)) {
+ quota_error(dquot->dq_sb, "dquota write failed");
+ if (ret >= 0)
+ ret = -EIO;
+ goto out;
+ }
+ ret = 0;
+
+out:
+ dqstats_inc(DQST_WRITES);
+
+ return ret;
+}
+
+/* Magics of new quota format */
+#define V2_INITQMAGICS {\
+ 0xd9c01f11, /* USRQUOTA */\
+ 0xd9c01927 /* GRPQUOTA */\
+}
+
+/* Header of new quota format */
+struct v2_disk_dqheader {
+ __le32 dqh_magic; /* Magic number identifying file */
+ __le32 dqh_version; /* File version */
+};
+
+static int v1_check_quota_file(struct super_block *sb, int type)
+{
+ struct inode *inode = sb_dqopt(sb)->files[type];
+ ulong blocks;
+ size_t off;
+ struct v2_disk_dqheader dqhead;
+ ssize_t size;
+ loff_t isize;
+ static const uint quota_magics[] = V2_INITQMAGICS;
+
+ isize = i_size_read(inode);
+ if (!isize)
+ return 0;
+ blocks = isize >> BLOCK_SIZE_BITS;
+ off = isize & (BLOCK_SIZE - 1);
+ if ((blocks % sizeof(struct v1_disk_dqblk) * BLOCK_SIZE + off) %
+ sizeof(struct v1_disk_dqblk))
+ return 0;
+ /* Doublecheck whether we didn't get file with new format - with old
+ * quotactl() this could happen */
+ size = sb->s_op->quota_read(sb, type, (char *)&dqhead,
+ sizeof(struct v2_disk_dqheader), 0);
+ if (size != sizeof(struct v2_disk_dqheader))
+ return 1; /* Probably not new format */
+ if (le32_to_cpu(dqhead.dqh_magic) != quota_magics[type])
+ return 1; /* Definitely not new format */
+ printk(KERN_INFO
+ "VFS: %s: Refusing to turn on old quota format on given file."
+ " It probably contains newer quota format.\n", sb->s_id);
+ return 0; /* Seems like a new format file -> refuse it */
+}
+
+static int v1_read_file_info(struct super_block *sb, int type)
+{
+ struct quota_info *dqopt = sb_dqopt(sb);
+ struct v1_disk_dqblk dqblk;
+ int ret;
+
+ ret = sb->s_op->quota_read(sb, type, (char *)&dqblk,
+ sizeof(struct v1_disk_dqblk), v1_dqoff(0));
+ if (ret != sizeof(struct v1_disk_dqblk)) {
+ if (ret >= 0)
+ ret = -EIO;
+ goto out;
+ }
+ ret = 0;
+ /* limits are stored as unsigned 32-bit data */
+ dqopt->info[type].dqi_max_spc_limit = 0xffffffffULL << QUOTABLOCK_BITS;
+ dqopt->info[type].dqi_max_ino_limit = 0xffffffff;
+ dqopt->info[type].dqi_igrace =
+ dqblk.dqb_itime ? dqblk.dqb_itime : MAX_IQ_TIME;
+ dqopt->info[type].dqi_bgrace =
+ dqblk.dqb_btime ? dqblk.dqb_btime : MAX_DQ_TIME;
+out:
+ return ret;
+}
+
+static int v1_write_file_info(struct super_block *sb, int type)
+{
+ struct quota_info *dqopt = sb_dqopt(sb);
+ struct v1_disk_dqblk dqblk;
+ int ret;
+
+ dqopt->info[type].dqi_flags &= ~DQF_INFO_DIRTY;
+ ret = sb->s_op->quota_read(sb, type, (char *)&dqblk,
+ sizeof(struct v1_disk_dqblk), v1_dqoff(0));
+ if (ret != sizeof(struct v1_disk_dqblk)) {
+ if (ret >= 0)
+ ret = -EIO;
+ goto out;
+ }
+ dqblk.dqb_itime = dqopt->info[type].dqi_igrace;
+ dqblk.dqb_btime = dqopt->info[type].dqi_bgrace;
+ ret = sb->s_op->quota_write(sb, type, (char *)&dqblk,
+ sizeof(struct v1_disk_dqblk), v1_dqoff(0));
+ if (ret == sizeof(struct v1_disk_dqblk))
+ ret = 0;
+ else if (ret > 0)
+ ret = -EIO;
+out:
+ return ret;
+}
+
+static const struct quota_format_ops v1_format_ops = {
+ .check_quota_file = v1_check_quota_file,
+ .read_file_info = v1_read_file_info,
+ .write_file_info = v1_write_file_info,
+ .free_file_info = NULL,
+ .read_dqblk = v1_read_dqblk,
+ .commit_dqblk = v1_commit_dqblk,
+};
+
+static struct quota_format_type v1_quota_format = {
+ .qf_fmt_id = QFMT_VFS_OLD,
+ .qf_ops = &v1_format_ops,
+ .qf_owner = THIS_MODULE
+};
+
+static int __init init_v1_quota_format(void)
+{
+ return register_quota_format(&v1_quota_format);
+}
+
+static void __exit exit_v1_quota_format(void)
+{
+ unregister_quota_format(&v1_quota_format);
+}
+
+module_init(init_v1_quota_format);
+module_exit(exit_v1_quota_format);
+
Code Review / kvmfornfv.git / blobdiff