[PATCH v7] ubifs: introduce UBIFS_ATIME_SUPPORT to ubifs
Dongsheng Yang
yangds.fnst at cn.fujitsu.com
Fri Nov 6 20:46:11 PST 2015
To make ubifs support atime flexily, this commit introduces
a Kconfig option named as UBIFS_ATIME_SUPPORT.
With UBIFS_ATIME_SUPPORT=n:
ubifs keeps the full compatibility to no_atime from
the start of ubifs.
=================UBIFS_ATIME_SUPPORT=n=======================
-o - no atime
-o atime - no atime
-o noatime - no atime
-o relatime - no atime
-o strictatime - no atime
-o lazyatime - no atime
With UBIFS_ATIME_SUPPORT=y:
ubifs supports the atime same with other main stream
file systems.
=================UBIFS_ATIME_SUPPORT=y=======================
-o - default behavior (relatime currently)
-o atime - atime support
-o noatime - no atime support
-o relatime - relative atime support
-o strictatime - strict atime support
-o lazyatime - lazy atime support
Signed-off-by: Dongsheng Yang <yangds.fnst at cn.fujitsu.com>
Reviewed-by: Richard Weinberger <richard at nod.at>
---
fs/ubifs/Kconfig | 15 +++++++++++++++
fs/ubifs/dir.c | 3 +++
fs/ubifs/file.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
fs/ubifs/super.c | 12 ++++++++++--
fs/ubifs/ubifs.h | 3 +++
5 files changed, 81 insertions(+), 2 deletions(-)
diff --git a/fs/ubifs/Kconfig b/fs/ubifs/Kconfig
index ba66d50..7ff7712 100644
--- a/fs/ubifs/Kconfig
+++ b/fs/ubifs/Kconfig
@@ -35,3 +35,18 @@ config UBIFS_FS_ZLIB
default y
help
Zlib compresses better than LZO but it is slower. Say 'Y' if unsure.
+
+config UBIFS_ATIME_SUPPORT
+ bool "Access time support" if UBIFS_FS
+ depends on UBIFS_FS
+ default n
+ help
+ Originally UBIFS did not support atime, because it looked like a bad idea due
+ increased flash wear. This option adds atime support and it is disabled by default
+ to preserve the old behavior. If you enable this option, UBIFS starts updating atime,
+ which means that file-system read operations will cause writes (inode atime
+ updates). This may affect file-system performance and increase flash device wear,
+ so be careful. How often atime is updated depends on the selected strategy:
+ strictatime is the "heavy", relatime is "lighter", etc.
+
+ If unsure, say 'N'
diff --git a/fs/ubifs/dir.c b/fs/ubifs/dir.c
index 5c27c66..a822148 100644
--- a/fs/ubifs/dir.c
+++ b/fs/ubifs/dir.c
@@ -1188,6 +1188,9 @@ const struct inode_operations ubifs_dir_inode_operations = {
.getxattr = ubifs_getxattr,
.listxattr = ubifs_listxattr,
.removexattr = ubifs_removexattr,
+#ifdef CONFIG_UBIFS_ATIME_SUPPORT
+ .update_time = ubifs_update_time,
+#endif
};
const struct file_operations ubifs_dir_operations = {
diff --git a/fs/ubifs/file.c b/fs/ubifs/file.c
index a3dfe2a..0edc128 100644
--- a/fs/ubifs/file.c
+++ b/fs/ubifs/file.c
@@ -1354,6 +1354,47 @@ static inline int mctime_update_needed(const struct inode *inode,
return 0;
}
+#ifdef CONFIG_UBIFS_ATIME_SUPPORT
+/**
+ * ubifs_update_time - update time of inode.
+ * @inode: inode to update
+ *
+ * This function updates time of the inode.
+ */
+int ubifs_update_time(struct inode *inode, struct timespec *time,
+ int flags)
+{
+ struct ubifs_inode *ui = ubifs_inode(inode);
+ struct ubifs_info *c = inode->i_sb->s_fs_info;
+ struct ubifs_budget_req req = { .dirtied_ino = 1,
+ .dirtied_ino_d = ALIGN(ui->data_len, 8) };
+ int iflags = I_DIRTY_TIME;
+ int err, release;
+
+ err = ubifs_budget_space(c, &req);
+ if (err)
+ return err;
+
+ mutex_lock(&ui->ui_mutex);
+ if (flags & S_ATIME)
+ inode->i_atime = *time;
+ if (flags & S_CTIME)
+ inode->i_ctime = *time;
+ if (flags & S_MTIME)
+ inode->i_mtime = *time;
+
+ if (!(inode->i_sb->s_flags & MS_LAZYTIME))
+ iflags |= I_DIRTY_SYNC;
+
+ release = ui->dirty;
+ __mark_inode_dirty(inode, iflags);
+ mutex_unlock(&ui->ui_mutex);
+ if (release)
+ ubifs_release_budget(c, &req);
+ return 0;
+}
+#endif
+
/**
* update_ctime - update mtime and ctime of an inode.
* @inode: inode to update
@@ -1537,6 +1578,9 @@ static int ubifs_file_mmap(struct file *file, struct vm_area_struct *vma)
if (err)
return err;
vma->vm_ops = &ubifs_file_vm_ops;
+#ifdef CONFIG_UBIFS_ATIME_SUPPORT
+ file_accessed(file);
+#endif
return 0;
}
@@ -1557,6 +1601,9 @@ const struct inode_operations ubifs_file_inode_operations = {
.getxattr = ubifs_getxattr,
.listxattr = ubifs_listxattr,
.removexattr = ubifs_removexattr,
+#ifdef CONFIG_UBIFS_ATIME_SUPPORT
+ .update_time = ubifs_update_time,
+#endif
};
const struct inode_operations ubifs_symlink_inode_operations = {
@@ -1568,6 +1615,9 @@ const struct inode_operations ubifs_symlink_inode_operations = {
.getxattr = ubifs_getxattr,
.listxattr = ubifs_listxattr,
.removexattr = ubifs_removexattr,
+#ifdef CONFIG_UBIFS_ATIME_SUPPORT
+ .update_time = ubifs_update_time,
+#endif
};
const struct file_operations ubifs_file_operations = {
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index 9547a278..8ee3133 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -128,7 +128,10 @@ struct inode *ubifs_iget(struct super_block *sb, unsigned long inum)
if (err)
goto out_ino;
- inode->i_flags |= (S_NOCMTIME | S_NOATIME);
+ inode->i_flags |= S_NOCMTIME;
+#ifndef CONFIG_UBIFS_ATIME_SUPPORT
+ inode->i_flags |= S_NOATIME;
+#endif
set_nlink(inode, le32_to_cpu(ino->nlink));
i_uid_write(inode, le32_to_cpu(ino->uid));
i_gid_write(inode, le32_to_cpu(ino->gid));
@@ -2139,7 +2142,12 @@ static struct dentry *ubifs_mount(struct file_system_type *fs_type, int flags,
if (err)
goto out_deact;
/* We do not support atime */
- sb->s_flags |= MS_ACTIVE | MS_NOATIME;
+ sb->s_flags |= MS_ACTIVE;
+#ifndef CONFIG_UBIFS_ATIME_SUPPORT
+ sb->s_flags |= MS_NOATIME;
+#else
+ ubifs_msg(c, "full atime support is enabled.");
+#endif
}
/* 'fill_super()' opens ubi again so we must close it here */
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index de75902..7e1f1f3 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -1746,6 +1746,9 @@ int ubifs_calc_dark(const struct ubifs_info *c, int spc);
/* file.c */
int ubifs_fsync(struct file *file, loff_t start, loff_t end, int datasync);
int ubifs_setattr(struct dentry *dentry, struct iattr *attr);
+#ifdef CONFIG_UBIFS_ATIME_SUPPORT
+int ubifs_update_time(struct inode *inode, struct timespec *time, int flags);
+#endif
/* dir.c */
struct inode *ubifs_new_inode(struct ubifs_info *c, const struct inode *dir,
--
1.8.4.2
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