1 files changed, 237 insertions, 0 deletions

diff --git a/fs/quota/quota_v2.c b/fs/quota/quota_v2.c
new file mode 100644
index 000000000000..a5475fb1ae44
--- /dev/null
+++ b/fs/quota/quota_v2.c
@@ -0,0 +1,237 @@
+/*
+ *      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");
+
+#define __QUOTA_V2_PARANOIA
+
+static void v2_mem2diskdqb(void *dp, struct dquot *dquot);
+static void v2_disk2memdqb(struct dquot *dquot, void *dp);
+static int v2_is_id(void *dp, struct dquot *dquot);
+
+static struct qtree_fmt_operations v2_qtree_ops = {
+        .mem2disk_dqblk = v2_mem2diskdqb,
+        .disk2mem_dqblk = v2_disk2memdqb,
+        .is_id = v2_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;
+}
+
+/* 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;
+        ssize_t size;
+        static const uint quota_magics[] = V2_INITQMAGICS;
+        static const uint quota_versions[] = V2_INITQVERSIONS;
+ 
+        size = sb->s_op->quota_read(sb, type, (char *)&dqhead,
+                                    sizeof(struct v2_disk_dqheader), 0);
+        if (size != sizeof(struct v2_disk_dqheader)) {
+                printk("quota_v2: failed read expected=%zd got=%zd\n",
+                        sizeof(struct v2_disk_dqheader), size);
+                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 mem_dqinfo *info = sb_dqinfo(sb, type);
+        struct qtree_mem_dqinfo *qinfo;
+        ssize_t size;
+
+        size = sb->s_op->quota_read(sb, type, (char *)&dinfo,
+               sizeof(struct v2_disk_dqinfo), V2_DQINFOOFF);
+        if (size != sizeof(struct v2_disk_dqinfo)) {
+                printk(KERN_WARNING "Can't read info structure on device %s.\n",
+                        sb->s_id);
+                return -1;
+        }
+        info->dqi_priv = kmalloc(sizeof(struct qtree_mem_dqinfo), GFP_NOFS);
+        if (!info->dqi_priv) {
+                printk(KERN_WARNING
+                       "Not enough memory for quota information structure.\n");
+                return -1;
+        }
+        qinfo = info->dqi_priv;
+        /* limits are stored as unsigned 32-bit data */
+        info->dqi_maxblimit = 0xffffffff;
+        info->dqi_maxilimit = 0xffffffff;
+        info->dqi_bgrace = le32_to_cpu(dinfo.dqi_bgrace);
+        info->dqi_igrace = le32_to_cpu(dinfo.dqi_igrace);
+        info->dqi_flags = le32_to_cpu(dinfo.dqi_flags);
+        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);
+        qinfo->dqi_entry_size = sizeof(struct v2_disk_dqblk);
+        qinfo->dqi_ops = &v2_qtree_ops;
+        return 0;
+}
+
+/* Write information header to quota file */
+static int v2_write_file_info(struct super_block *sb, int type)
+{
+        struct v2_disk_dqinfo dinfo;
+        struct mem_dqinfo *info = sb_dqinfo(sb, type);
+        struct qtree_mem_dqinfo *qinfo = info->dqi_priv;
+        ssize_t size;
+
+        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);
+        dinfo.dqi_flags = cpu_to_le32(info->dqi_flags & DQF_MASK);
+        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);
+        if (size != sizeof(struct v2_disk_dqinfo)) {
+                printk(KERN_WARNING "Can't write info structure on device %s.\n",
+                        sb->s_id);
+                return -1;
+        }
+        return 0;
+}
+
+static void v2_disk2memdqb(struct dquot *dquot, void *dp)
+{
+        struct v2_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 v2_disk_dqblk));
+        empty.dqb_itime = cpu_to_le64(1);
+        if (!memcmp(&empty, dp, sizeof(struct v2_disk_dqblk)))
+                m->dqb_itime = 0;
+}
+
+static void v2_mem2diskdqb(void *dp, struct dquot *dquot)
+{
+        struct v2_disk_dqblk *d = dp;
+        struct mem_dqblk *m = &dquot->dq_dqb;
+        struct qtree_mem_dqinfo *info =
+                        sb_dqinfo(dquot->dq_sb, dquot->dq_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(dquot->dq_id);
+        if (qtree_entry_unused(info, dp))
+                d->dqb_itime = cpu_to_le64(1);
+}
+
+static int v2_is_id(void *dp, struct dquot *dquot)
+{
+        struct v2_disk_dqblk *d = dp;
+        struct qtree_mem_dqinfo *info =
+                        sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv;
+
+        if (qtree_entry_unused(info, dp))
+                return 0;
+        return le32_to_cpu(d->dqb_id) == dquot->dq_id;
+}
+
+static int v2_read_dquot(struct dquot *dquot)
+{
+        return qtree_read_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv, dquot);
+}
+
+static int v2_write_dquot(struct dquot *dquot)
+{
+        return qtree_write_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv, dquot);
+}
+
+static int v2_release_dquot(struct dquot *dquot)
+{
+        return qtree_release_dquot(sb_dqinfo(dquot->dq_sb, dquot->dq_type)->dqi_priv, dquot);
+}
+
+static int v2_free_file_info(struct super_block *sb, int type)
+{
+        kfree(sb_dqinfo(sb, type)->dqi_priv);
+        return 0;
+}
+
+static 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,
+};
+
+static struct quota_format_type v2_quota_format = {
+        .qf_fmt_id      = QFMT_VFS_V0,
+        .qf_ops         = &v2_format_ops,
+        .qf_owner       = THIS_MODULE
+};
+
+static int __init init_v2_quota_format(void)
+{
+        return register_quota_format(&v2_quota_format);
+}
+
+static void __exit exit_v2_quota_format(void)
+{
+        unregister_quota_format(&v2_quota_format);
+}
+
+module_init(init_v2_quota_format);
+module_exit(exit_v2_quota_format);