Re: [PATCH v3] f2fs: add an ioctl to disable GC for specific file

From: Chao Yu
Date: Wed Jan 03 2018 - 02:35:09 EST


On 2018/1/3 11:21, Jaegeuk Kim wrote:
> This patch gives a flag to disable GC on given file, which would be useful, when
> user wants to keep its block map. It also conducts in-place-update for dontmove
> file.
>
> Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
> ---
>
> Change log from v2:
> - modify ioctl to allow users unpin the file
>
> fs/f2fs/data.c | 2 ++
> fs/f2fs/f2fs.h | 28 +++++++++++++++++++++-
> fs/f2fs/file.c | 64 +++++++++++++++++++++++++++++++++++++++++++++++++
> fs/f2fs/gc.c | 11 +++++++++
> fs/f2fs/gc.h | 2 ++
> fs/f2fs/sysfs.c | 2 ++
> include/linux/f2fs_fs.h | 9 ++++++-
> 7 files changed, 116 insertions(+), 2 deletions(-)
>
> diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
> index 449b0aaa3905..45f65a5b9871 100644
> --- a/fs/f2fs/data.c
> +++ b/fs/f2fs/data.c
> @@ -1395,6 +1395,8 @@ static inline bool need_inplace_update(struct f2fs_io_info *fio)
> {
> struct inode *inode = fio->page->mapping->host;
>
> + if (f2fs_is_pinned_file(inode))
> + return true;
> if (S_ISDIR(inode->i_mode) || f2fs_is_atomic_file(inode))
> return false;
> if (is_cold_data(fio->page))
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index a0e8eec23125..f4b7d73695a7 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -350,6 +350,7 @@ static inline bool __has_cursum_space(struct f2fs_journal *journal,
> #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_PIN_FILE _IOW(F2FS_IOCTL_MAGIC, 13, __u32)
>
> #define F2FS_IOC_SET_ENCRYPTION_POLICY FS_IOC_SET_ENCRYPTION_POLICY
> #define F2FS_IOC_GET_ENCRYPTION_POLICY FS_IOC_GET_ENCRYPTION_POLICY
> @@ -587,7 +588,10 @@ struct f2fs_inode_info {
> unsigned long i_flags; /* keep an inode flags for ioctl */
> unsigned char i_advise; /* use to give file attribute hints */
> unsigned char i_dir_level; /* use for dentry level for large dir */
> - unsigned int i_current_depth; /* use only in directory structure */
> + union {
> + unsigned int i_current_depth; /* only for directory depth */
> + unsigned short i_gc_failures; /* only for regular file */
> + };
> unsigned int i_pino; /* parent inode number */
> umode_t i_acl_mode; /* keep file acl mode temporarily */
>
> @@ -1133,6 +1137,9 @@ struct f2fs_sb_info {
> /* threshold for converting bg victims for fg */
> u64 fggc_threshold;
>
> + /* threshold for gc trials on pinned files */
> + u64 gc_pin_file_threshold;
> +
> /* maximum # of trials to find a victim segment for SSR and GC */
> unsigned int max_victim_search;
>
> @@ -2124,6 +2131,7 @@ enum {
> FI_HOT_DATA, /* indicate file is hot */
> FI_EXTRA_ATTR, /* indicate file has extra attribute */
> FI_PROJ_INHERIT, /* indicate file inherits projectid */
> + FI_PIN_FILE, /* indicate file should not be gced */
> };
>
> static inline void __mark_inode_dirty_flag(struct inode *inode,
> @@ -2137,6 +2145,7 @@ static inline void __mark_inode_dirty_flag(struct inode *inode,
> return;
> case FI_DATA_EXIST:
> case FI_INLINE_DOTS:
> + case FI_PIN_FILE:
> f2fs_mark_inode_dirty_sync(inode, true);
> }
> }
> @@ -2217,6 +2226,13 @@ static inline void f2fs_i_depth_write(struct inode *inode, unsigned int depth)
> f2fs_mark_inode_dirty_sync(inode, true);
> }
>
> +static inline void f2fs_i_gc_failures_write(struct inode *inode,
> + unsigned int count)
> +{
> + F2FS_I(inode)->i_gc_failures = count;
> + f2fs_mark_inode_dirty_sync(inode, true);
> +}
> +
> static inline void f2fs_i_xnid_write(struct inode *inode, nid_t xnid)
> {
> F2FS_I(inode)->i_xattr_nid = xnid;
> @@ -2245,6 +2261,8 @@ static inline void get_inline_info(struct inode *inode, struct f2fs_inode *ri)
> set_bit(FI_INLINE_DOTS, &fi->flags);
> if (ri->i_inline & F2FS_EXTRA_ATTR)
> set_bit(FI_EXTRA_ATTR, &fi->flags);
> + if (ri->i_inline & F2FS_PIN_FILE)
> + set_bit(FI_PIN_FILE, &fi->flags);
> }
>
> static inline void set_raw_inline(struct inode *inode, struct f2fs_inode *ri)
> @@ -2263,6 +2281,8 @@ static inline void set_raw_inline(struct inode *inode, struct f2fs_inode *ri)
> ri->i_inline |= F2FS_INLINE_DOTS;
> if (is_inode_flag_set(inode, FI_EXTRA_ATTR))
> ri->i_inline |= F2FS_EXTRA_ATTR;
> + if (is_inode_flag_set(inode, FI_PIN_FILE))
> + ri->i_inline |= F2FS_PIN_FILE;
> }
>
> static inline int f2fs_has_extra_attr(struct inode *inode)
> @@ -2308,6 +2328,11 @@ static inline int f2fs_has_inline_dots(struct inode *inode)
> return is_inode_flag_set(inode, FI_INLINE_DOTS);
> }
>
> +static inline bool f2fs_is_pinned_file(struct inode *inode)
> +{
> + return is_inode_flag_set(inode, FI_PIN_FILE);
> +}
> +
> static inline bool f2fs_is_atomic_file(struct inode *inode)
> {
> return is_inode_flag_set(inode, FI_ATOMIC_FILE);
> @@ -2523,6 +2548,7 @@ int truncate_hole(struct inode *inode, pgoff_t pg_start, pgoff_t pg_end);
> void truncate_data_blocks_range(struct dnode_of_data *dn, int count);
> long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg);
> long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
> +int f2fs_pin_file_control(struct inode *inode, bool inc);
>
> /*
> * inode.c
> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> index 322aab9d91b5..a7ee659c5a61 100644
> --- a/fs/f2fs/file.c
> +++ b/fs/f2fs/file.c
> @@ -2669,6 +2669,67 @@ static int f2fs_ioc_fssetxattr(struct file *filp, unsigned long arg)
> return 0;
> }
>
> +int f2fs_pin_file_control(struct inode *inode, bool inc)
> +{
> + struct f2fs_inode_info *fi = F2FS_I(inode);
> + struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
> +
> + /* Use i_gc_failures for normal file as a risk signal. */
> + if (inc)
> + f2fs_i_gc_failures_write(inode, fi->i_gc_failures + 1);
> +
> + if (fi->i_gc_failures > sbi->gc_pin_file_threshold) {
> + f2fs_msg(sbi->sb, KERN_WARNING,
> + "%s: Enable GC = ino %lx after %x GC trials\n",
> + __func__, inode->i_ino, fi->i_gc_failures);
> + return -EAGAIN;
> + }
> + return 0;
> +}
> +
> +static int f2fs_ioc_set_pin_file(struct file *filp, unsigned long arg)
> +{
> + struct inode *inode = file_inode(filp);
> + __u32 pin;
> + int ret = 0;
> +
> + if (!inode_owner_or_capable(inode))
> + return -EACCES;
> +
> + if (get_user(pin, (__u32 __user *)arg))
> + return -EFAULT;
> +
> + if (!S_ISREG(inode->i_mode))
> + return -EINVAL;
> +
> + if (f2fs_readonly(F2FS_I_SB(inode)->sb))
> + return -EROFS;

mnt_want_write_file(filp)?

> +
> + inode_lock(inode);
> +
> + if (!pin) {
> + clear_inode_flag(inode, FI_PIN_FILE);
> + F2FS_I(inode)->i_gc_failures = 0;
> + goto done;
> + }
> +
> + if (f2fs_pin_file_control(inode, false)) {
> + ret = -EAGAIN;
> + goto out;
> + }
> + ret = f2fs_convert_inline_inode(inode);
> + if (ret)
> + goto out;
> +
> + set_inode_flag(inode, FI_PIN_FILE);
> + ret = F2FS_I(inode)->i_gc_failures;
> +done:
> + f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);
> +out:
> + inode_unlock(inode);

mnt_drop_write_file(filp)?

Other part looks good to me. ;)

Reviewed-by: Chao Yu <yuchao0@xxxxxxxxxx>

Thanks,

> + return ret;
> +}
> +
> long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
> {
> if (unlikely(f2fs_cp_error(F2FS_I_SB(file_inode(filp)))))
> @@ -2719,6 +2780,8 @@ long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
> return f2fs_ioc_fsgetxattr(filp, arg);
> case F2FS_IOC_FSSETXATTR:
> return f2fs_ioc_fssetxattr(filp, arg);
> + case F2FS_IOC_SET_PIN_FILE:
> + return f2fs_ioc_set_pin_file(filp, arg);
> default:
> return -ENOTTY;
> }
> @@ -2794,6 +2857,7 @@ long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
> case F2FS_IOC_GET_FEATURES:
> case F2FS_IOC_FSGETXATTR:
> case F2FS_IOC_FSSETXATTR:
> + case F2FS_IOC_SET_PIN_FILE:
> break;
> default:
> return -ENOIOCTLCMD;
> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
> index 5d5bba462f26..9bffef153a12 100644
> --- a/fs/f2fs/gc.c
> +++ b/fs/f2fs/gc.c
> @@ -624,6 +624,11 @@ static void move_data_block(struct inode *inode, block_t bidx,
> if (f2fs_is_atomic_file(inode))
> goto out;
>
> + if (f2fs_is_pinned_file(inode)) {
> + f2fs_pin_file_control(inode, true);
> + goto out;
> + }
> +
> set_new_dnode(&dn, inode, NULL, NULL, 0);
> err = get_dnode_of_data(&dn, bidx, LOOKUP_NODE);
> if (err)
> @@ -720,6 +725,11 @@ static void move_data_page(struct inode *inode, block_t bidx, int gc_type,
>
> if (f2fs_is_atomic_file(inode))
> goto out;
> + if (f2fs_is_pinned_file(inode)) {
> + if (gc_type == FG_GC)
> + f2fs_pin_file_control(inode, true);
> + goto out;
> + }
>
> if (gc_type == BG_GC) {
> if (PageWriteback(page))
> @@ -1091,6 +1101,7 @@ void build_gc_manager(struct f2fs_sb_info *sbi)
>
> sbi->fggc_threshold = div64_u64((main_count - ovp_count) *
> BLKS_PER_SEC(sbi), (main_count - resv_count));
> + sbi->gc_pin_file_threshold = DEF_GC_FAILED_PINNED_FILES;
>
> /* give warm/cold data area from slower device */
> if (sbi->s_ndevs && sbi->segs_per_sec == 1)
> diff --git a/fs/f2fs/gc.h b/fs/f2fs/gc.h
> index 9325191fab2d..33310165cb78 100644
> --- a/fs/f2fs/gc.h
> +++ b/fs/f2fs/gc.h
> @@ -20,6 +20,8 @@
> #define LIMIT_INVALID_BLOCK 40 /* percentage over total user space */
> #define LIMIT_FREE_BLOCK 40 /* percentage over invalid + free space */
>
> +#define DEF_GC_FAILED_PINNED_FILES 1024
> +
> /* Search max. number of dirty segments to select a victim segment */
> #define DEF_MAX_VICTIM_SEARCH 4096 /* covers 8GB */
>
> diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
> index ab6028c332aa..41887e6ec1b3 100644
> --- a/fs/f2fs/sysfs.c
> +++ b/fs/f2fs/sysfs.c
> @@ -301,6 +301,7 @@ F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, cp_interval, interval_time[CP_TIME]);
> F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, idle_interval, interval_time[REQ_TIME]);
> F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, iostat_enable, iostat_enable);
> F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, readdir_ra, readdir_ra);
> +F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, gc_pin_file_thresh, gc_pin_file_threshold);
> #ifdef CONFIG_F2FS_FAULT_INJECTION
> F2FS_RW_ATTR(FAULT_INFO_RATE, f2fs_fault_info, inject_rate, inject_rate);
> F2FS_RW_ATTR(FAULT_INFO_TYPE, f2fs_fault_info, inject_type, inject_type);
> @@ -349,6 +350,7 @@ static struct attribute *f2fs_attrs[] = {
> ATTR_LIST(idle_interval),
> ATTR_LIST(iostat_enable),
> ATTR_LIST(readdir_ra),
> + ATTR_LIST(gc_pin_file_thresh),
> #ifdef CONFIG_F2FS_FAULT_INJECTION
> ATTR_LIST(inject_rate),
> ATTR_LIST(inject_type),
> diff --git a/include/linux/f2fs_fs.h b/include/linux/f2fs_fs.h
> index 43e98d30d2df..cfb522e6affc 100644
> --- a/include/linux/f2fs_fs.h
> +++ b/include/linux/f2fs_fs.h
> @@ -212,6 +212,7 @@ struct f2fs_extent {
> #define F2FS_DATA_EXIST 0x08 /* file inline data exist flag */
> #define F2FS_INLINE_DOTS 0x10 /* file having implicit dot dentries */
> #define F2FS_EXTRA_ATTR 0x20 /* file having extra attribute */
> +#define F2FS_PIN_FILE 0x40 /* file should not be gced */
>
> struct f2fs_inode {
> __le16 i_mode; /* file mode */
> @@ -229,7 +230,13 @@ struct f2fs_inode {
> __le32 i_ctime_nsec; /* change time in nano scale */
> __le32 i_mtime_nsec; /* modification time in nano scale */
> __le32 i_generation; /* file version (for NFS) */
> - __le32 i_current_depth; /* only for directory depth */
> + union {
> + __le32 i_current_depth; /* only for directory depth */
> + __le16 i_gc_failures; /*
> + * # of gc failures on pinned file.
> + * only for regular files.
> + */
> + };
> __le32 i_xattr_nid; /* nid to save xattr */
> __le32 i_flags; /* file attributes */
> __le32 i_pino; /* parent inode number */
>