Message ID | 20170721201108.18408-1-jaegeuk@kernel.org (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
> On Jul 21, 2017, at 2:11 PM, Jaegeuk Kim <jaegeuk@kernel.org> wrote: > > This patch adds an ioctl to provide feature information to user. > For exapmle, SQLite can use this ioctl to detect whether f2fs support atomic > write or not. Just for reference, ext4 exposes functionality that the kernel supports via a file in /sys/fs/ext4/features/{feature_name} so that it is possible to check [ -e /sys/fs/ext4/features/lazy_itable_init ] in a shell script also. There are also per-filesystem tunables in /sys/fs/ext4/{device}/ and it wouldn't be a bad idea to expose per-filesystem features something like /sys/fs/{fstype}/{device}/features/{feature_name} so that it is easily checked by userspace tools using [ -e $feature ] in bash or access() in programs rather than an ioctl. Cheers, Andreas > > Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org> > --- > fs/f2fs/f2fs.h | 2 ++ > fs/f2fs/file.c | 13 +++++++++++++ > 2 files changed, 15 insertions(+) > > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h > index e06d4e4b4579..5c46a462b56e 100644 > --- a/fs/f2fs/f2fs.h > +++ b/fs/f2fs/f2fs.h > @@ -112,6 +112,7 @@ struct f2fs_mount_info { > > #define F2FS_FEATURE_ENCRYPT 0x0001 > #define F2FS_FEATURE_BLKZONED 0x0002 > +#define F2FS_FEATURE_ATOMIC_WRITE 0x0004 > > #define F2FS_HAS_FEATURE(sb, mask) \ > ((F2FS_SB(sb)->raw_super->feature & cpu_to_le32(mask)) != 0) > @@ -308,6 +309,7 @@ static inline bool __has_cursum_space(struct f2fs_journal *journal, > struct f2fs_flush_device) > #define F2FS_IOC_GARBAGE_COLLECT_RANGE _IOW(F2FS_IOCTL_MAGIC, 11, \ > struct f2fs_gc_range) > +#define F2FS_IOC_GET_FEATURES _IOR(F2FS_IOCTL_MAGIC, 12, __u32) > > #define F2FS_IOC_SET_ENCRYPTION_POLICY FS_IOC_SET_ENCRYPTION_POLICY > #define F2FS_IOC_GET_ENCRYPTION_POLICY FS_IOC_GET_ENCRYPTION_POLICY > diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c > index 2706130c261b..0e07b5b18cfa 100644 > --- a/fs/f2fs/file.c > +++ b/fs/f2fs/file.c > @@ -2384,6 +2384,16 @@ static int f2fs_ioc_flush_device(struct file *filp, unsigned long arg) > return ret; > } > > +static int f2fs_ioc_get_features(struct file *filp, unsigned long arg) > +{ > + struct inode *inode = file_inode(filp); > + u32 sb_feature = le32_to_cpu(F2FS_I_SB(inode)->raw_super->feature); > + > + /* Must validate to set it with SQLite behavior in Android. */ > + sb_feature |= F2FS_FEATURE_ATOMIC_WRITE; > + > + return put_user(sb_feature, (u32 __user *)arg); > +} > > long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) > { > @@ -2426,6 +2436,8 @@ long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) > return f2fs_ioc_move_range(filp, arg); > case F2FS_IOC_FLUSH_DEVICE: > return f2fs_ioc_flush_device(filp, arg); > + case F2FS_IOC_GET_FEATURES: > + return f2fs_ioc_get_features(filp, arg); > default: > return -ENOTTY; > } > @@ -2491,6 +2503,7 @@ long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) > case F2FS_IOC_DEFRAGMENT: > case F2FS_IOC_MOVE_RANGE: > case F2FS_IOC_FLUSH_DEVICE: > + case F2FS_IOC_GET_FEATURES: > break; > default: > return -ENOIOCTLCMD; > -- > 2.13.0.rc1.294.g07d810a77f-goog > Cheers, Andreas
On 07/21, Andreas Dilger wrote: > > On Jul 21, 2017, at 2:11 PM, Jaegeuk Kim <jaegeuk@kernel.org> wrote: > > > > This patch adds an ioctl to provide feature information to user. > > For exapmle, SQLite can use this ioctl to detect whether f2fs support atomic > > write or not. > > Just for reference, ext4 exposes functionality that the kernel supports via > a file in /sys/fs/ext4/features/{feature_name} so that it is possible to > check [ -e /sys/fs/ext4/features/lazy_itable_init ] in a shell script also. Thank you for the info. I'll write a patch to expose sysfs entries as well. :) For sqlite in Android, I think ioctl would be a simpler interface to check the feature flag rather than to open another sysfs files, regarding to latency and additional selinux changes. > > There are also per-filesystem tunables in /sys/fs/ext4/{device}/ and it > wouldn't be a bad idea to expose per-filesystem features something like > /sys/fs/{fstype}/{device}/features/{feature_name} so that it is easily > checked by userspace tools using [ -e $feature ] in bash or access() > in programs rather than an ioctl. Yeah, agreed. Thanks, > > Cheers, Andreas > > > > > Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org> > > --- > > fs/f2fs/f2fs.h | 2 ++ > > fs/f2fs/file.c | 13 +++++++++++++ > > 2 files changed, 15 insertions(+) > > > > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h > > index e06d4e4b4579..5c46a462b56e 100644 > > --- a/fs/f2fs/f2fs.h > > +++ b/fs/f2fs/f2fs.h > > @@ -112,6 +112,7 @@ struct f2fs_mount_info { > > > > #define F2FS_FEATURE_ENCRYPT 0x0001 > > #define F2FS_FEATURE_BLKZONED 0x0002 > > +#define F2FS_FEATURE_ATOMIC_WRITE 0x0004 > > > > #define F2FS_HAS_FEATURE(sb, mask) \ > > ((F2FS_SB(sb)->raw_super->feature & cpu_to_le32(mask)) != 0) > > @@ -308,6 +309,7 @@ static inline bool __has_cursum_space(struct f2fs_journal *journal, > > struct f2fs_flush_device) > > #define F2FS_IOC_GARBAGE_COLLECT_RANGE _IOW(F2FS_IOCTL_MAGIC, 11, \ > > struct f2fs_gc_range) > > +#define F2FS_IOC_GET_FEATURES _IOR(F2FS_IOCTL_MAGIC, 12, __u32) > > > > #define F2FS_IOC_SET_ENCRYPTION_POLICY FS_IOC_SET_ENCRYPTION_POLICY > > #define F2FS_IOC_GET_ENCRYPTION_POLICY FS_IOC_GET_ENCRYPTION_POLICY > > diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c > > index 2706130c261b..0e07b5b18cfa 100644 > > --- a/fs/f2fs/file.c > > +++ b/fs/f2fs/file.c > > @@ -2384,6 +2384,16 @@ static int f2fs_ioc_flush_device(struct file *filp, unsigned long arg) > > return ret; > > } > > > > +static int f2fs_ioc_get_features(struct file *filp, unsigned long arg) > > +{ > > + struct inode *inode = file_inode(filp); > > + u32 sb_feature = le32_to_cpu(F2FS_I_SB(inode)->raw_super->feature); > > + > > + /* Must validate to set it with SQLite behavior in Android. */ > > + sb_feature |= F2FS_FEATURE_ATOMIC_WRITE; > > + > > + return put_user(sb_feature, (u32 __user *)arg); > > +} > > > > long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) > > { > > @@ -2426,6 +2436,8 @@ long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) > > return f2fs_ioc_move_range(filp, arg); > > case F2FS_IOC_FLUSH_DEVICE: > > return f2fs_ioc_flush_device(filp, arg); > > + case F2FS_IOC_GET_FEATURES: > > + return f2fs_ioc_get_features(filp, arg); > > default: > > return -ENOTTY; > > } > > @@ -2491,6 +2503,7 @@ long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) > > case F2FS_IOC_DEFRAGMENT: > > case F2FS_IOC_MOVE_RANGE: > > case F2FS_IOC_FLUSH_DEVICE: > > + case F2FS_IOC_GET_FEATURES: > > break; > > default: > > return -ENOIOCTLCMD; > > -- > > 2.13.0.rc1.294.g07d810a77f-goog > > > > > Cheers, Andreas > > > > >
On 2017/7/22 4:11, Jaegeuk Kim wrote: > This patch adds an ioctl to provide feature information to user. > For exapmle, SQLite can use this ioctl to detect whether f2fs support atomic > write or not. > > Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org> Reviewed-by: Chao Yu <yuchao0@huawei.com> Thanks, > --- > fs/f2fs/f2fs.h | 2 ++ > fs/f2fs/file.c | 13 +++++++++++++ > 2 files changed, 15 insertions(+) > > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h > index e06d4e4b4579..5c46a462b56e 100644 > --- a/fs/f2fs/f2fs.h > +++ b/fs/f2fs/f2fs.h > @@ -112,6 +112,7 @@ struct f2fs_mount_info { > > #define F2FS_FEATURE_ENCRYPT 0x0001 > #define F2FS_FEATURE_BLKZONED 0x0002 > +#define F2FS_FEATURE_ATOMIC_WRITE 0x0004 > > #define F2FS_HAS_FEATURE(sb, mask) \ > ((F2FS_SB(sb)->raw_super->feature & cpu_to_le32(mask)) != 0) > @@ -308,6 +309,7 @@ static inline bool __has_cursum_space(struct f2fs_journal *journal, > struct f2fs_flush_device) > #define F2FS_IOC_GARBAGE_COLLECT_RANGE _IOW(F2FS_IOCTL_MAGIC, 11, \ > struct f2fs_gc_range) > +#define F2FS_IOC_GET_FEATURES _IOR(F2FS_IOCTL_MAGIC, 12, __u32) > > #define F2FS_IOC_SET_ENCRYPTION_POLICY FS_IOC_SET_ENCRYPTION_POLICY > #define F2FS_IOC_GET_ENCRYPTION_POLICY FS_IOC_GET_ENCRYPTION_POLICY > diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c > index 2706130c261b..0e07b5b18cfa 100644 > --- a/fs/f2fs/file.c > +++ b/fs/f2fs/file.c > @@ -2384,6 +2384,16 @@ static int f2fs_ioc_flush_device(struct file *filp, unsigned long arg) > return ret; > } > > +static int f2fs_ioc_get_features(struct file *filp, unsigned long arg) > +{ > + struct inode *inode = file_inode(filp); > + u32 sb_feature = le32_to_cpu(F2FS_I_SB(inode)->raw_super->feature); > + > + /* Must validate to set it with SQLite behavior in Android. */ > + sb_feature |= F2FS_FEATURE_ATOMIC_WRITE; > + > + return put_user(sb_feature, (u32 __user *)arg); > +} > > long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) > { > @@ -2426,6 +2436,8 @@ long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) > return f2fs_ioc_move_range(filp, arg); > case F2FS_IOC_FLUSH_DEVICE: > return f2fs_ioc_flush_device(filp, arg); > + case F2FS_IOC_GET_FEATURES: > + return f2fs_ioc_get_features(filp, arg); > default: > return -ENOTTY; > } > @@ -2491,6 +2503,7 @@ long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) > case F2FS_IOC_DEFRAGMENT: > case F2FS_IOC_MOVE_RANGE: > case F2FS_IOC_FLUSH_DEVICE: > + case F2FS_IOC_GET_FEATURES: > break; > default: > return -ENOIOCTLCMD; >
Hi Jaegeuk, I noted that the patch ("f2fs: give a try to do atomic write in -ENOMEM case") hasn't been sent to mailing list before been merged. Could you please send it out, and please add: Reviewed-by: Chao Yu <yuchao0@huawei.com> Thanks, On 2017/7/22 4:11, Jaegeuk Kim wrote: > This patch adds an ioctl to provide feature information to user. > For exapmle, SQLite can use this ioctl to detect whether f2fs support atomic > write or not. > > Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org> > --- > fs/f2fs/f2fs.h | 2 ++ > fs/f2fs/file.c | 13 +++++++++++++ > 2 files changed, 15 insertions(+) > > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h > index e06d4e4b4579..5c46a462b56e 100644 > --- a/fs/f2fs/f2fs.h > +++ b/fs/f2fs/f2fs.h > @@ -112,6 +112,7 @@ struct f2fs_mount_info { > > #define F2FS_FEATURE_ENCRYPT 0x0001 > #define F2FS_FEATURE_BLKZONED 0x0002 > +#define F2FS_FEATURE_ATOMIC_WRITE 0x0004 > > #define F2FS_HAS_FEATURE(sb, mask) \ > ((F2FS_SB(sb)->raw_super->feature & cpu_to_le32(mask)) != 0) > @@ -308,6 +309,7 @@ static inline bool __has_cursum_space(struct f2fs_journal *journal, > struct f2fs_flush_device) > #define F2FS_IOC_GARBAGE_COLLECT_RANGE _IOW(F2FS_IOCTL_MAGIC, 11, \ > struct f2fs_gc_range) > +#define F2FS_IOC_GET_FEATURES _IOR(F2FS_IOCTL_MAGIC, 12, __u32) > > #define F2FS_IOC_SET_ENCRYPTION_POLICY FS_IOC_SET_ENCRYPTION_POLICY > #define F2FS_IOC_GET_ENCRYPTION_POLICY FS_IOC_GET_ENCRYPTION_POLICY > diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c > index 2706130c261b..0e07b5b18cfa 100644 > --- a/fs/f2fs/file.c > +++ b/fs/f2fs/file.c > @@ -2384,6 +2384,16 @@ static int f2fs_ioc_flush_device(struct file *filp, unsigned long arg) > return ret; > } > > +static int f2fs_ioc_get_features(struct file *filp, unsigned long arg) > +{ > + struct inode *inode = file_inode(filp); > + u32 sb_feature = le32_to_cpu(F2FS_I_SB(inode)->raw_super->feature); > + > + /* Must validate to set it with SQLite behavior in Android. */ > + sb_feature |= F2FS_FEATURE_ATOMIC_WRITE; > + > + return put_user(sb_feature, (u32 __user *)arg); > +} > > long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) > { > @@ -2426,6 +2436,8 @@ long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) > return f2fs_ioc_move_range(filp, arg); > case F2FS_IOC_FLUSH_DEVICE: > return f2fs_ioc_flush_device(filp, arg); > + case F2FS_IOC_GET_FEATURES: > + return f2fs_ioc_get_features(filp, arg); > default: > return -ENOTTY; > } > @@ -2491,6 +2503,7 @@ long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) > case F2FS_IOC_DEFRAGMENT: > case F2FS_IOC_MOVE_RANGE: > case F2FS_IOC_FLUSH_DEVICE: > + case F2FS_IOC_GET_FEATURES: > break; > default: > return -ENOIOCTLCMD; >
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index e06d4e4b4579..5c46a462b56e 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -112,6 +112,7 @@ struct f2fs_mount_info { #define F2FS_FEATURE_ENCRYPT 0x0001 #define F2FS_FEATURE_BLKZONED 0x0002 +#define F2FS_FEATURE_ATOMIC_WRITE 0x0004 #define F2FS_HAS_FEATURE(sb, mask) \ ((F2FS_SB(sb)->raw_super->feature & cpu_to_le32(mask)) != 0) @@ -308,6 +309,7 @@ static inline bool __has_cursum_space(struct f2fs_journal *journal, struct f2fs_flush_device) #define F2FS_IOC_GARBAGE_COLLECT_RANGE _IOW(F2FS_IOCTL_MAGIC, 11, \ struct f2fs_gc_range) +#define F2FS_IOC_GET_FEATURES _IOR(F2FS_IOCTL_MAGIC, 12, __u32) #define F2FS_IOC_SET_ENCRYPTION_POLICY FS_IOC_SET_ENCRYPTION_POLICY #define F2FS_IOC_GET_ENCRYPTION_POLICY FS_IOC_GET_ENCRYPTION_POLICY diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index 2706130c261b..0e07b5b18cfa 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -2384,6 +2384,16 @@ static int f2fs_ioc_flush_device(struct file *filp, unsigned long arg) return ret; } +static int f2fs_ioc_get_features(struct file *filp, unsigned long arg) +{ + struct inode *inode = file_inode(filp); + u32 sb_feature = le32_to_cpu(F2FS_I_SB(inode)->raw_super->feature); + + /* Must validate to set it with SQLite behavior in Android. */ + sb_feature |= F2FS_FEATURE_ATOMIC_WRITE; + + return put_user(sb_feature, (u32 __user *)arg); +} long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { @@ -2426,6 +2436,8 @@ long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) return f2fs_ioc_move_range(filp, arg); case F2FS_IOC_FLUSH_DEVICE: return f2fs_ioc_flush_device(filp, arg); + case F2FS_IOC_GET_FEATURES: + return f2fs_ioc_get_features(filp, arg); default: return -ENOTTY; } @@ -2491,6 +2503,7 @@ long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) case F2FS_IOC_DEFRAGMENT: case F2FS_IOC_MOVE_RANGE: case F2FS_IOC_FLUSH_DEVICE: + case F2FS_IOC_GET_FEATURES: break; default: return -ENOIOCTLCMD;
This patch adds an ioctl to provide feature information to user. For exapmle, SQLite can use this ioctl to detect whether f2fs support atomic write or not. Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org> --- fs/f2fs/f2fs.h | 2 ++ fs/f2fs/file.c | 13 +++++++++++++ 2 files changed, 15 insertions(+)