[RFC v2 76/83] Ioctl support.

Andiry Xu
2018-03-10T18:24:15Z

NOVA appends link change entry to the inode log to implement
SETFLAGS and SETVERSION.

Signed-off-by: Andiry Xu <jix024@cs.ucsd.edu>
---
fs/nova/Makefile | 4 +-
fs/nova/dir.c | 4 ++
fs/nova/file.c | 4 ++
fs/nova/inode.h | 2 +
fs/nova/ioctl.c | 184 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
fs/nova/nova.h | 7 +++
6 files changed, 203 insertions(+), 2 deletions(-)
create mode 100644 fs/nova/ioctl.c

diff --git a/fs/nova/Makefile b/fs/nova/Makefile
index 7bf6403..87e56c6 100644
--- a/fs/nova/Makefile
+++ b/fs/nova/Makefile
@@ -4,5 +4,5 @@

obj-$(CONFIG_NOVA_FS) += nova.o

-nova-y := balloc.o bbuild.o dax.o dir.o file.o inode.o journal.o log.o namei.o\
- rebuild.o stats.o super.o symlink.o
+nova-y := balloc.o bbuild.o dax.o dir.o file.o inode.o ioctl.o journal.o\
+ log.o namei.o rebuild.o stats.o super.o symlink.o
diff --git a/fs/nova/dir.c b/fs/nova/dir.c
index 47ee9ad..3694d9d 100644
--- a/fs/nova/dir.c
+++ b/fs/nova/dir.c
@@ -513,4 +513,8 @@ const struct file_operations nova_dir_operations = {
.read = generic_read_dir,
.iterate = nova_readdir,
.fsync = noop_fsync,
+ .unlocked_ioctl = nova_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = nova_compat_ioctl,
+#endif
};
diff --git a/fs/nova/file.c b/fs/nova/file.c
index 7e90415..2b70b9d 100644
--- a/fs/nova/file.c
+++ b/fs/nova/file.c
@@ -714,7 +714,11 @@ const struct file_operations nova_dax_file_operations = {
.open = nova_open,
.fsync = nova_fsync,
.flush = nova_flush,
+ .unlocked_ioctl = nova_ioctl,
.fallocate = nova_fallocate,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = nova_compat_ioctl,
+#endif
};

const struct inode_operations nova_file_inode_operations = {
diff --git a/fs/nova/inode.h b/fs/nova/inode.h
index 693aa90..086a7cb 100644
--- a/fs/nova/inode.h
+++ b/fs/nova/inode.h
@@ -264,6 +264,8 @@ int nova_delete_file_tree(struct super_block *sb,
struct nova_inode_info_header *sih, unsigned long start_blocknr,
unsigned long last_blocknr, bool delete_nvmm, bool delete_dead,
u64 epoch_id);
+extern void nova_set_inode_flags(struct inode *inode, struct nova_inode *pi,
+ unsigned int flags);
unsigned long nova_find_region(struct inode *inode, loff_t *offset, int hole);
extern void nova_evict_inode(struct inode *inode);
extern int nova_write_inode(struct inode *inode, struct writeback_control *wbc);
diff --git a/fs/nova/ioctl.c b/fs/nova/ioctl.c
new file mode 100644
index 0000000..2509371
--- /dev/null
+++ b/fs/nova/ioctl.c
@@ -0,0 +1,184 @@
+/*
+ * BRIEF DESCRIPTION
+ *
+ * Ioctl operations.
+ *
+ * Copyright 2015-2016 Regents of the University of California,
+ * UCSD Non-Volatile Systems Lab, Andiry Xu <jix024@cs.ucsd.edu>
+ * Copyright 2012-2013 Intel Corporation
+ * Copyright 2010-2011 Marco Stornelli <marco.stornelli@gmail.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/capability.h>
+#include <linux/time.h>
+#include <linux/sched.h>
+#include <linux/compat.h>
+#include <linux/mount.h>
+#include "nova.h"
+#include "inode.h"
+
+long nova_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+ struct address_space *mapping = filp->f_mapping;
+ struct inode *inode = mapping->host;
+ struct nova_inode_info *si = NOVA_I(inode);
+ struct nova_inode_info_header *sih = &si->header;
+ struct nova_inode *pi;
+ struct super_block *sb = inode->i_sb;
+ struct nova_inode_update update;
+ unsigned int flags;
+ int ret;
+
+ pi = nova_get_inode(sb, inode);
+ if (!pi)
+ return -EACCES;
+
+ switch (cmd) {
+ case FS_IOC_GETFLAGS:
+ flags = (sih->i_flags) & NOVA_FL_USER_VISIBLE;
+ return put_user(flags, (int __user *)arg);
+ case FS_IOC_SETFLAGS: {
+ unsigned int oldflags;
+ u64 old_linkc = 0;
+ u64 epoch_id;
+
+ ret = mnt_want_write_file(filp);
+ if (ret)
+ return ret;
+
+ if (!inode_owner_or_capable(inode)) {
+ ret = -EPERM;
+ goto flags_out;
+ }
+
+ if (get_user(flags, (int __user *)arg)) {
+ ret = -EFAULT;
+ goto flags_out;
+ }
+
+ inode_lock(inode);
+ sih_lock(sih);
+ oldflags = le32_to_cpu(pi->i_flags);
+
+ if ((flags ^ oldflags) &
+ (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
+ if (!capable(CAP_LINUX_IMMUTABLE)) {
+ inode_unlock(inode);
+ ret = -EPERM;
+ goto flags_out_unlock;
+ }
+ }
+
+ if (!S_ISDIR(inode->i_mode))
+ flags &= ~FS_DIRSYNC_FL;
+
+ epoch_id = nova_get_epoch_id(sb);
+ flags = flags & FS_FL_USER_MODIFIABLE;
+ flags |= oldflags & ~FS_FL_USER_MODIFIABLE;
+ inode->i_ctime = current_time(inode);
+ nova_set_inode_flags(inode, pi, flags);
+ sih->i_flags = flags;
+
+ update.tail = 0;
+ ret = nova_append_link_change_entry(sb, pi, inode,
+ &update, &old_linkc, epoch_id);
+ if (!ret) {
+ nova_update_inode(sb, inode, pi, &update);
+ nova_invalidate_link_change_entry(sb, old_linkc);
+ }
+ sih->trans_id++;
+flags_out_unlock:
+ sih_unlock(sih);
+ inode_unlock(inode);
+flags_out:
+ mnt_drop_write_file(filp);
+ return ret;
+ }
+ case FS_IOC_GETVERSION:
+ return put_user(inode->i_generation, (int __user *)arg);
+ case FS_IOC_SETVERSION: {
+ u64 old_linkc = 0;
+ u64 epoch_id;
+ __u32 generation;
+
+ if (!inode_owner_or_capable(inode))
+ return -EPERM;
+ ret = mnt_want_write_file(filp);
+ if (ret)
+ return ret;
+ if (get_user(generation, (int __user *)arg)) {
+ ret = -EFAULT;
+ goto setversion_out;
+ }
+
+ epoch_id = nova_get_epoch_id(sb);
+ inode_lock(inode);
+ sih_lock(sih);
+ inode->i_ctime = current_time(inode);
+ inode->i_generation = generation;
+
+ update.tail = 0;
+ ret = nova_append_link_change_entry(sb, pi, inode,
+ &update, &old_linkc, epoch_id);
+ if (!ret) {
+ nova_update_inode(sb, inode, pi, &update);
+ nova_invalidate_link_change_entry(sb, old_linkc);
+ }
+ sih->trans_id++;
+ sih_unlock(sih);
+ inode_unlock(inode);
+setversion_out:
+ mnt_drop_write_file(filp);
+ return ret;
+ }
+ case NOVA_PRINT_TIMING: {
+ nova_print_timing_stats(sb);
+ return 0;
+ }
+ case NOVA_CLEAR_STATS: {
+ nova_clear_stats(sb);
+ return 0;
+ }
+ case NOVA_PRINT_LOG: {
+ nova_print_inode_log(sb, inode);
+ return 0;
+ }
+ case NOVA_PRINT_LOG_PAGES: {
+ nova_print_inode_log_pages(sb, inode);
+ return 0;
+ }
+ case NOVA_PRINT_FREE_LISTS: {
+ nova_print_free_lists(sb);
+ return 0;
+ }
+ default:
+ return -ENOTTY;
+ }
+}
+
+#ifdef CONFIG_COMPAT
+long nova_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ switch (cmd) {
+ case FS_IOC32_GETFLAGS:
+ cmd = FS_IOC_GETFLAGS;
+ break;
+ case FS_IOC32_SETFLAGS:
+ cmd = FS_IOC_SETFLAGS;
+ break;
+ case FS_IOC32_GETVERSION:
+ cmd = FS_IOC_GETVERSION;
+ break;
+ case FS_IOC32_SETVERSION:
+ cmd = FS_IOC_SETVERSION;
+ break;
+ default:
+ return -ENOIOCTLCMD;
+ }
+ return nova_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
+}
+#endif
diff --git a/fs/nova/nova.h b/fs/nova/nova.h
index d209cfc..ab9153e 100644
--- a/fs/nova/nova.h
+++ b/fs/nova/nova.h
@@ -515,6 +515,13 @@ int nova_remove_dentry(struct dentry *dentry, int dec_link,
extern const struct file_operations nova_dax_file_operations;
extern const struct inode_operations nova_file_inode_operations;

+/* ioctl.c */
+extern long nova_ioctl(struct file *filp, unsigned int cmd, unsigned long arg);
+#ifdef CONFIG_COMPAT
+extern long nova_compat_ioctl(struct file *file, unsigned int cmd,
+ unsigned long arg);
+#endif
+
/* namei.c */
extern const struct inode_operations nova_dir_inode_operations;
extern const struct inode_operations nova_special_inode_operations;
--
2.7.4