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-rw-r--r--fs/quota/quota_v2.c437
1 files changed, 437 insertions, 0 deletions
diff --git a/fs/quota/quota_v2.c b/fs/quota/quota_v2.c
new file mode 100644
index 000000000..b1467f392
--- /dev/null
+++ b/fs/quota/quota_v2.c
@@ -0,0 +1,437 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * vfsv0 quota IO operations on file
+ */
+
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/mount.h>
+#include <linux/dqblk_v2.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/quotaops.h>
+
+#include <asm/byteorder.h>
+
+#include "quota_tree.h"
+#include "quotaio_v2.h"
+
+MODULE_AUTHOR("Jan Kara");
+MODULE_DESCRIPTION("Quota format v2 support");
+MODULE_LICENSE("GPL");
+
+static void v2r0_mem2diskdqb(void *dp, struct dquot *dquot);
+static void v2r0_disk2memdqb(struct dquot *dquot, void *dp);
+static int v2r0_is_id(void *dp, struct dquot *dquot);
+static void v2r1_mem2diskdqb(void *dp, struct dquot *dquot);
+static void v2r1_disk2memdqb(struct dquot *dquot, void *dp);
+static int v2r1_is_id(void *dp, struct dquot *dquot);
+
+static const struct qtree_fmt_operations v2r0_qtree_ops = {
+ .mem2disk_dqblk = v2r0_mem2diskdqb,
+ .disk2mem_dqblk = v2r0_disk2memdqb,
+ .is_id = v2r0_is_id,
+};
+
+static const struct qtree_fmt_operations v2r1_qtree_ops = {
+ .mem2disk_dqblk = v2r1_mem2diskdqb,
+ .disk2mem_dqblk = v2r1_disk2memdqb,
+ .is_id = v2r1_is_id,
+};
+
+#define QUOTABLOCK_BITS 10
+#define QUOTABLOCK_SIZE (1 << QUOTABLOCK_BITS)
+
+static inline qsize_t v2_stoqb(qsize_t space)
+{
+ return (space + QUOTABLOCK_SIZE - 1) >> QUOTABLOCK_BITS;
+}
+
+static inline qsize_t v2_qbtos(qsize_t blocks)
+{
+ return blocks << QUOTABLOCK_BITS;
+}
+
+static int v2_read_header(struct super_block *sb, int type,
+ struct v2_disk_dqheader *dqhead)
+{
+ ssize_t size;
+
+ size = sb->s_op->quota_read(sb, type, (char *)dqhead,
+ sizeof(struct v2_disk_dqheader), 0);
+ if (size != sizeof(struct v2_disk_dqheader)) {
+ quota_error(sb, "Failed header read: expected=%zd got=%zd",
+ sizeof(struct v2_disk_dqheader), size);
+ if (size < 0)
+ return size;
+ return -EIO;
+ }
+ return 0;
+}
+
+/* Check whether given file is really vfsv0 quotafile */
+static int v2_check_quota_file(struct super_block *sb, int type)
+{
+ struct v2_disk_dqheader dqhead;
+ static const uint quota_magics[] = V2_INITQMAGICS;
+ static const uint quota_versions[] = V2_INITQVERSIONS;
+
+ if (v2_read_header(sb, type, &dqhead))
+ return 0;
+ if (le32_to_cpu(dqhead.dqh_magic) != quota_magics[type] ||
+ le32_to_cpu(dqhead.dqh_version) > quota_versions[type])
+ return 0;
+ return 1;
+}
+
+/* Read information header from quota file */
+static int v2_read_file_info(struct super_block *sb, int type)
+{
+ struct v2_disk_dqinfo dinfo;
+ struct v2_disk_dqheader dqhead;
+ struct quota_info *dqopt = sb_dqopt(sb);
+ struct mem_dqinfo *info = &dqopt->info[type];
+ struct qtree_mem_dqinfo *qinfo;
+ ssize_t size;
+ unsigned int version;
+ int ret;
+
+ down_read(&dqopt->dqio_sem);
+ ret = v2_read_header(sb, type, &dqhead);
+ if (ret < 0)
+ goto out;
+ version = le32_to_cpu(dqhead.dqh_version);
+ if ((info->dqi_fmt_id == QFMT_VFS_V0 && version != 0) ||
+ (info->dqi_fmt_id == QFMT_VFS_V1 && version != 1)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ size = sb->s_op->quota_read(sb, type, (char *)&dinfo,
+ sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF);
+ if (size != sizeof(struct v2_disk_dqinfo)) {
+ quota_error(sb, "Can't read info structure");
+ if (size < 0)
+ ret = size;
+ else
+ ret = -EIO;
+ goto out;
+ }
+ info->dqi_priv = kmalloc(sizeof(struct qtree_mem_dqinfo), GFP_NOFS);
+ if (!info->dqi_priv) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ qinfo = info->dqi_priv;
+ if (version == 0) {
+ /* limits are stored as unsigned 32-bit data */
+ info->dqi_max_spc_limit = 0xffffffffLL << QUOTABLOCK_BITS;
+ info->dqi_max_ino_limit = 0xffffffff;
+ } else {
+ /*
+ * Used space is stored as unsigned 64-bit value in bytes but
+ * quota core supports only signed 64-bit values so use that
+ * as a limit
+ */
+ info->dqi_max_spc_limit = 0x7fffffffffffffffLL; /* 2^63-1 */
+ info->dqi_max_ino_limit = 0x7fffffffffffffffLL;
+ }
+ info->dqi_bgrace = le32_to_cpu(dinfo.dqi_bgrace);
+ info->dqi_igrace = le32_to_cpu(dinfo.dqi_igrace);
+ /* No flags currently supported */
+ info->dqi_flags = 0;
+ qinfo->dqi_sb = sb;
+ qinfo->dqi_type = type;
+ qinfo->dqi_blocks = le32_to_cpu(dinfo.dqi_blocks);
+ qinfo->dqi_free_blk = le32_to_cpu(dinfo.dqi_free_blk);
+ qinfo->dqi_free_entry = le32_to_cpu(dinfo.dqi_free_entry);
+ qinfo->dqi_blocksize_bits = V2_DQBLKSIZE_BITS;
+ qinfo->dqi_usable_bs = 1 << V2_DQBLKSIZE_BITS;
+ qinfo->dqi_qtree_depth = qtree_depth(qinfo);
+ if (version == 0) {
+ qinfo->dqi_entry_size = sizeof(struct v2r0_disk_dqblk);
+ qinfo->dqi_ops = &v2r0_qtree_ops;
+ } else {
+ qinfo->dqi_entry_size = sizeof(struct v2r1_disk_dqblk);
+ qinfo->dqi_ops = &v2r1_qtree_ops;
+ }
+ ret = -EUCLEAN;
+ /* Some sanity checks of the read headers... */
+ if ((loff_t)qinfo->dqi_blocks << qinfo->dqi_blocksize_bits >
+ i_size_read(sb_dqopt(sb)->files[type])) {
+ quota_error(sb, "Number of blocks too big for quota file size (%llu > %llu).",
+ (loff_t)qinfo->dqi_blocks << qinfo->dqi_blocksize_bits,
+ i_size_read(sb_dqopt(sb)->files[type]));
+ goto out_free;
+ }
+ if (qinfo->dqi_free_blk >= qinfo->dqi_blocks) {
+ quota_error(sb, "Free block number too big (%u >= %u).",
+ qinfo->dqi_free_blk, qinfo->dqi_blocks);
+ goto out_free;
+ }
+ if (qinfo->dqi_free_entry >= qinfo->dqi_blocks) {
+ quota_error(sb, "Block with free entry too big (%u >= %u).",
+ qinfo->dqi_free_entry, qinfo->dqi_blocks);
+ goto out_free;
+ }
+ ret = 0;
+out_free:
+ if (ret) {
+ kfree(info->dqi_priv);
+ info->dqi_priv = NULL;
+ }
+out:
+ up_read(&dqopt->dqio_sem);
+ return ret;
+}
+
+/* Write information header to quota file */
+static int v2_write_file_info(struct super_block *sb, int type)
+{
+ struct v2_disk_dqinfo dinfo;
+ struct quota_info *dqopt = sb_dqopt(sb);
+ struct mem_dqinfo *info = &dqopt->info[type];
+ struct qtree_mem_dqinfo *qinfo = info->dqi_priv;
+ ssize_t size;
+
+ down_write(&dqopt->dqio_sem);
+ spin_lock(&dq_data_lock);
+ info->dqi_flags &= ~DQF_INFO_DIRTY;
+ dinfo.dqi_bgrace = cpu_to_le32(info->dqi_bgrace);
+ dinfo.dqi_igrace = cpu_to_le32(info->dqi_igrace);
+ /* No flags currently supported */
+ dinfo.dqi_flags = cpu_to_le32(0);
+ spin_unlock(&dq_data_lock);
+ dinfo.dqi_blocks = cpu_to_le32(qinfo->dqi_blocks);
+ dinfo.dqi_free_blk = cpu_to_le32(qinfo->dqi_free_blk);
+ dinfo.dqi_free_entry = cpu_to_le32(qinfo->dqi_free_entry);
+ size = sb->s_op->quota_write(sb, type, (char *)&dinfo,
+ sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF);
+ up_write(&dqopt->dqio_sem);
+ if (size != sizeof(struct v2_disk_dqinfo)) {
+ quota_error(sb, "Can't write info structure");
+ return -1;
+ }
+ return 0;
+}
+
+static void v2r0_disk2memdqb(struct dquot *dquot, void *dp)
+{
+ struct v2r0_disk_dqblk *d = dp, empty;
+ struct mem_dqblk *m = &dquot->dq_dqb;
+
+ m->dqb_ihardlimit = le32_to_cpu(d->dqb_ihardlimit);
+ m->dqb_isoftlimit = le32_to_cpu(d->dqb_isoftlimit);
+ m->dqb_curinodes = le32_to_cpu(d->dqb_curinodes);
+ m->dqb_itime = le64_to_cpu(d->dqb_itime);
+ m->dqb_bhardlimit = v2_qbtos(le32_to_cpu(d->dqb_bhardlimit));
+ m->dqb_bsoftlimit = v2_qbtos(le32_to_cpu(d->dqb_bsoftlimit));
+ m->dqb_curspace = le64_to_cpu(d->dqb_curspace);
+ m->dqb_btime = le64_to_cpu(d->dqb_btime);
+ /* We need to escape back all-zero structure */
+ memset(&empty, 0, sizeof(struct v2r0_disk_dqblk));
+ empty.dqb_itime = cpu_to_le64(1);
+ if (!memcmp(&empty, dp, sizeof(struct v2r0_disk_dqblk)))
+ m->dqb_itime = 0;
+}
+
+static void v2r0_mem2diskdqb(void *dp, struct dquot *dquot)
+{
+ struct v2r0_disk_dqblk *d = dp;
+ struct mem_dqblk *m = &dquot->dq_dqb;
+ struct qtree_mem_dqinfo *info =
+ sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv;
+
+ d->dqb_ihardlimit = cpu_to_le32(m->dqb_ihardlimit);
+ d->dqb_isoftlimit = cpu_to_le32(m->dqb_isoftlimit);
+ d->dqb_curinodes = cpu_to_le32(m->dqb_curinodes);
+ d->dqb_itime = cpu_to_le64(m->dqb_itime);
+ d->dqb_bhardlimit = cpu_to_le32(v2_stoqb(m->dqb_bhardlimit));
+ d->dqb_bsoftlimit = cpu_to_le32(v2_stoqb(m->dqb_bsoftlimit));
+ d->dqb_curspace = cpu_to_le64(m->dqb_curspace);
+ d->dqb_btime = cpu_to_le64(m->dqb_btime);
+ d->dqb_id = cpu_to_le32(from_kqid(&init_user_ns, dquot->dq_id));
+ if (qtree_entry_unused(info, dp))
+ d->dqb_itime = cpu_to_le64(1);
+}
+
+static int v2r0_is_id(void *dp, struct dquot *dquot)
+{
+ struct v2r0_disk_dqblk *d = dp;
+ struct qtree_mem_dqinfo *info =
+ sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv;
+
+ if (qtree_entry_unused(info, dp))
+ return 0;
+ return qid_eq(make_kqid(&init_user_ns, dquot->dq_id.type,
+ le32_to_cpu(d->dqb_id)),
+ dquot->dq_id);
+}
+
+static void v2r1_disk2memdqb(struct dquot *dquot, void *dp)
+{
+ struct v2r1_disk_dqblk *d = dp, empty;
+ struct mem_dqblk *m = &dquot->dq_dqb;
+
+ m->dqb_ihardlimit = le64_to_cpu(d->dqb_ihardlimit);
+ m->dqb_isoftlimit = le64_to_cpu(d->dqb_isoftlimit);
+ m->dqb_curinodes = le64_to_cpu(d->dqb_curinodes);
+ m->dqb_itime = le64_to_cpu(d->dqb_itime);
+ m->dqb_bhardlimit = v2_qbtos(le64_to_cpu(d->dqb_bhardlimit));
+ m->dqb_bsoftlimit = v2_qbtos(le64_to_cpu(d->dqb_bsoftlimit));
+ m->dqb_curspace = le64_to_cpu(d->dqb_curspace);
+ m->dqb_btime = le64_to_cpu(d->dqb_btime);
+ /* We need to escape back all-zero structure */
+ memset(&empty, 0, sizeof(struct v2r1_disk_dqblk));
+ empty.dqb_itime = cpu_to_le64(1);
+ if (!memcmp(&empty, dp, sizeof(struct v2r1_disk_dqblk)))
+ m->dqb_itime = 0;
+}
+
+static void v2r1_mem2diskdqb(void *dp, struct dquot *dquot)
+{
+ struct v2r1_disk_dqblk *d = dp;
+ struct mem_dqblk *m = &dquot->dq_dqb;
+ struct qtree_mem_dqinfo *info =
+ sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv;
+
+ d->dqb_ihardlimit = cpu_to_le64(m->dqb_ihardlimit);
+ d->dqb_isoftlimit = cpu_to_le64(m->dqb_isoftlimit);
+ d->dqb_curinodes = cpu_to_le64(m->dqb_curinodes);
+ d->dqb_itime = cpu_to_le64(m->dqb_itime);
+ d->dqb_bhardlimit = cpu_to_le64(v2_stoqb(m->dqb_bhardlimit));
+ d->dqb_bsoftlimit = cpu_to_le64(v2_stoqb(m->dqb_bsoftlimit));
+ d->dqb_curspace = cpu_to_le64(m->dqb_curspace);
+ d->dqb_btime = cpu_to_le64(m->dqb_btime);
+ d->dqb_id = cpu_to_le32(from_kqid(&init_user_ns, dquot->dq_id));
+ d->dqb_pad = 0;
+ if (qtree_entry_unused(info, dp))
+ d->dqb_itime = cpu_to_le64(1);
+}
+
+static int v2r1_is_id(void *dp, struct dquot *dquot)
+{
+ struct v2r1_disk_dqblk *d = dp;
+ struct qtree_mem_dqinfo *info =
+ sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv;
+
+ if (qtree_entry_unused(info, dp))
+ return 0;
+ return qid_eq(make_kqid(&init_user_ns, dquot->dq_id.type,
+ le32_to_cpu(d->dqb_id)),
+ dquot->dq_id);
+}
+
+static int v2_read_dquot(struct dquot *dquot)
+{
+ struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
+ int ret;
+
+ down_read(&dqopt->dqio_sem);
+ ret = qtree_read_dquot(
+ sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv,
+ dquot);
+ up_read(&dqopt->dqio_sem);
+ return ret;
+}
+
+static int v2_write_dquot(struct dquot *dquot)
+{
+ struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
+ int ret;
+ bool alloc = false;
+
+ /*
+ * If space for dquot is already allocated, we don't need any
+ * protection as we'll only overwrite the place of dquot. We are
+ * still protected by concurrent writes of the same dquot by
+ * dquot->dq_lock.
+ */
+ if (!dquot->dq_off) {
+ alloc = true;
+ down_write(&dqopt->dqio_sem);
+ } else {
+ down_read(&dqopt->dqio_sem);
+ }
+ ret = qtree_write_dquot(
+ sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv,
+ dquot);
+ if (alloc)
+ up_write(&dqopt->dqio_sem);
+ else
+ up_read(&dqopt->dqio_sem);
+ return ret;
+}
+
+static int v2_release_dquot(struct dquot *dquot)
+{
+ struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
+ int ret;
+
+ down_write(&dqopt->dqio_sem);
+ ret = qtree_release_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_id.type)->dqi_priv, dquot);
+ up_write(&dqopt->dqio_sem);
+
+ return ret;
+}
+
+static int v2_free_file_info(struct super_block *sb, int type)
+{
+ kfree(sb_dqinfo(sb, type)->dqi_priv);
+ return 0;
+}
+
+static int v2_get_next_id(struct super_block *sb, struct kqid *qid)
+{
+ struct quota_info *dqopt = sb_dqopt(sb);
+ int ret;
+
+ down_read(&dqopt->dqio_sem);
+ ret = qtree_get_next_id(sb_dqinfo(sb, qid->type)->dqi_priv, qid);
+ up_read(&dqopt->dqio_sem);
+ return ret;
+}
+
+static const struct quota_format_ops v2_format_ops = {
+ .check_quota_file = v2_check_quota_file,
+ .read_file_info = v2_read_file_info,
+ .write_file_info = v2_write_file_info,
+ .free_file_info = v2_free_file_info,
+ .read_dqblk = v2_read_dquot,
+ .commit_dqblk = v2_write_dquot,
+ .release_dqblk = v2_release_dquot,
+ .get_next_id = v2_get_next_id,
+};
+
+static struct quota_format_type v2r0_quota_format = {
+ .qf_fmt_id = QFMT_VFS_V0,
+ .qf_ops = &v2_format_ops,
+ .qf_owner = THIS_MODULE
+};
+
+static struct quota_format_type v2r1_quota_format = {
+ .qf_fmt_id = QFMT_VFS_V1,
+ .qf_ops = &v2_format_ops,
+ .qf_owner = THIS_MODULE
+};
+
+static int __init init_v2_quota_format(void)
+{
+ int ret;
+
+ ret = register_quota_format(&v2r0_quota_format);
+ if (ret)
+ return ret;
+ return register_quota_format(&v2r1_quota_format);
+}
+
+static void __exit exit_v2_quota_format(void)
+{
+ unregister_quota_format(&v2r0_quota_format);
+ unregister_quota_format(&v2r1_quota_format);
+}
+
+module_init(init_v2_quota_format);
+module_exit(exit_v2_quota_format);