Re: [PATCH] f2fs: support compress extension update via sysfs interface
From: Jaegeuk Kim
Date: Wed Feb 07 2024 - 19:07:44 EST
On 02/07, Chao Yu wrote:
> Introduce /sys/fs/f2fs/<disk>/compress_extension to support
> adding/deleting compress extension via sysfs interface, in
> comparison to mount option, it's more easy to use and less
> authority issue for applications.
>
> Usage:
> - Query: cat /sys/fs/f2fs/<disk>/compress_extension
> - Add: echo '[c|n]extension' > /sys/fs/f2fs/<disk>/compress_extension
> - Del: echo '[c|n]!extension' > /sys/fs/f2fs/<disk>/compress_extension
> - [c] means add/del compress extension
> - [n] means add/del nocompress extension
>
> Signed-off-by: Sheng Yong <shengyong@xxxxxxxx>
> Signed-off-by: Chao Yu <chao@xxxxxxxxxx>
> ---
> Documentation/ABI/testing/sysfs-fs-f2fs | 10 ++++
> Documentation/filesystems/f2fs.rst | 6 ++-
> fs/f2fs/compress.c | 61 +++++++++++++++++++++++
> fs/f2fs/f2fs.h | 4 +-
> fs/f2fs/sysfs.c | 65 +++++++++++++++++++++++--
> 5 files changed, 139 insertions(+), 7 deletions(-)
>
> diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs b/Documentation/ABI/testing/sysfs-fs-f2fs
> index 48c135e24eb5..1f2cc0913e45 100644
> --- a/Documentation/ABI/testing/sysfs-fs-f2fs
> +++ b/Documentation/ABI/testing/sysfs-fs-f2fs
> @@ -762,3 +762,13 @@ Date: November 2023
> Contact: "Chao Yu" <chao@xxxxxxxxxx>
> Description: It controls to enable/disable IO aware feature for background discard.
> By default, the value is 1 which indicates IO aware is on.
> +
> +What: /sys/fs/f2fs/<disk>/compress_extension
> +Date: October 2023
> +Contact: "Chao Yu" <chao@xxxxxxxxxx>
> +Description: Used to control configure [|no]compress_extension list:
> + - Query: cat /sys/fs/f2fs/<disk>/compress_extension
> + - Add: echo '[c|n]extension' > /sys/fs/f2fs/<disk>/compress_extension
> + - Del: echo '[c|n]!extension' > /sys/fs/f2fs/<disk>/compress_extension
> + - [c] means add/del compress extension
> + - [n] means add/del nocompress extension
> diff --git a/Documentation/filesystems/f2fs.rst b/Documentation/filesystems/f2fs.rst
> index 32cbfa864f38..c82a8fd7316b 100644
> --- a/Documentation/filesystems/f2fs.rst
> +++ b/Documentation/filesystems/f2fs.rst
> @@ -821,17 +821,19 @@ Compression implementation
> all logical blocks in cluster contain valid data and compress ratio of
> cluster data is lower than specified threshold.
>
> -- To enable compression on regular inode, there are four ways:
> +- To enable compression on regular inode, there are five ways:
>
> * chattr +c file
> * chattr +c dir; touch dir/file
> * mount w/ -o compress_extension=ext; touch file.ext
> * mount w/ -o compress_extension=*; touch any_file
> + * echo '[c]ext' > /sys/fs/f2fs/<disk>/compress_extension; touch file.ext
>
> -- To disable compression on regular inode, there are two ways:
> +- To disable compression on regular inode, there are three ways:
>
> * chattr -c file
> * mount w/ -o nocompress_extension=ext; touch file.ext
> + * echo '[n]ext' > /sys/fs/f2fs/<disk>/compress_extension; touch file.ext
>
> - Priority in between FS_COMPR_FL, FS_NOCOMP_FS, extensions:
>
> diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c
> index 3dc488ce882b..a5257882c772 100644
> --- a/fs/f2fs/compress.c
> +++ b/fs/f2fs/compress.c
> @@ -20,6 +20,67 @@
> #include "segment.h"
> #include <trace/events/f2fs.h>
>
> +static int is_compress_extension_exist(struct f2fs_sb_info *sbi,
> + unsigned char (*ext)[F2FS_EXTENSION_LEN],
> + int ext_cnt, unsigned char *new_ext)
> +{
> + int i;
> +
> + for (i = 0; i < ext_cnt; i++) {
> + if (!strcasecmp(new_ext, ext[i]))
> + return i;
> + }
> + return -1;
> +}
> +
> +int f2fs_update_compress_extension(struct f2fs_sb_info *sbi,
> + unsigned char *new_ext, bool is_ext, bool set)
> +{
> + unsigned char (*ext)[F2FS_EXTENSION_LEN];
> + unsigned char *ext_cnt;
> +
> + if (is_ext) {
> + ext = F2FS_OPTION(sbi).extensions;
> + ext_cnt = &F2FS_OPTION(sbi).compress_ext_cnt;
> + } else {
> + ext = F2FS_OPTION(sbi).noextensions;
> + ext_cnt = &F2FS_OPTION(sbi).nocompress_ext_cnt;
> + }
> +
> + if (set) {
> + if (*ext_cnt >= COMPRESS_EXT_NUM)
> + return -EINVAL;
> +
> + if (is_compress_extension_exist(sbi,
> + F2FS_OPTION(sbi).extensions,
> + F2FS_OPTION(sbi).compress_ext_cnt,
> + new_ext) >= 0)
> + return -EEXIST;
> +
> + if (is_compress_extension_exist(sbi,
> + F2FS_OPTION(sbi).noextensions,
> + F2FS_OPTION(sbi).nocompress_ext_cnt,
> + new_ext) >= 0)
> + return -EEXIST;
> +
> + strcpy(ext[*ext_cnt], new_ext);
> + (*ext_cnt)++;
> + } else {
> + int pos = is_compress_extension_exist(sbi, ext,
> + *ext_cnt, new_ext);
> + if (pos < 0)
> + return -ENOENT;
> +
> + if (pos < *ext_cnt - 1)
> + memmove(ext + pos, ext + pos + 1,
> + F2FS_EXTENSION_LEN * (*ext_cnt - pos - 1));
> + memset(ext + *ext_cnt - 1, 0, F2FS_EXTENSION_LEN);
> + (*ext_cnt)--;
> + }
> +
> + return 0;
> +}
> +
> static struct kmem_cache *cic_entry_slab;
> static struct kmem_cache *dic_entry_slab;
>
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index c5e7460d1a0a..d44e2c43d8ab 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -186,7 +186,7 @@ struct f2fs_mount_info {
> unsigned char compress_level; /* compress level */
> bool compress_chksum; /* compressed data chksum */
> unsigned char compress_ext_cnt; /* extension count */
> - unsigned char nocompress_ext_cnt; /* nocompress extension count */
> + unsigned char nocompress_ext_cnt; /* nocompress extension count */
> int compress_mode; /* compression mode */
> unsigned char extensions[COMPRESS_EXT_NUM][F2FS_EXTENSION_LEN]; /* extensions */
> unsigned char noextensions[COMPRESS_EXT_NUM][F2FS_EXTENSION_LEN]; /* extensions */
> @@ -4273,6 +4273,8 @@ static inline bool f2fs_post_read_required(struct inode *inode)
> * compress.c
> */
> #ifdef CONFIG_F2FS_FS_COMPRESSION
> +int f2fs_update_compress_extension(struct f2fs_sb_info *sbi,
> + unsigned char *new_ext, bool is_ext, bool set);
> bool f2fs_is_compressed_page(struct page *page);
> struct page *f2fs_compress_control_page(struct page *page);
> int f2fs_prepare_compress_overwrite(struct inode *inode,
> diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
> index a7ec55c7bb20..a8f05a02e202 100644
> --- a/fs/f2fs/sysfs.c
> +++ b/fs/f2fs/sysfs.c
> @@ -39,6 +39,7 @@ enum {
> RESERVED_BLOCKS, /* struct f2fs_sb_info */
> CPRC_INFO, /* struct ckpt_req_control */
> ATGC_INFO, /* struct atgc_management */
> + MOUNT_INFO, /* struct f2fs_mount_info */
> };
>
> static const char *gc_mode_names[MAX_GC_MODE] = {
> @@ -89,6 +90,8 @@ static unsigned char *__struct_ptr(struct f2fs_sb_info *sbi, int struct_type)
> return (unsigned char *)&sbi->cprc_info;
> else if (struct_type == ATGC_INFO)
> return (unsigned char *)&sbi->am;
> + else if (struct_type == MOUNT_INFO)
> + return (unsigned char *)&F2FS_OPTION(sbi);
> return NULL;
> }
>
> @@ -358,6 +361,25 @@ static ssize_t f2fs_sbi_show(struct f2fs_attr *a,
>
> if (!strcmp(a->attr.name, "compr_new_inode"))
> return sysfs_emit(buf, "%u\n", sbi->compr_new_inode);
> +
> + if (!strcmp(a->attr.name, "compress_extension")) {
> + int len = 0, i;
> +
> + f2fs_down_read(&sbi->sb_lock);
> + len += scnprintf(buf + len, PAGE_SIZE - len,
> + "compress extension:\n");
> + for (i = 0; i < F2FS_OPTION(sbi).compress_ext_cnt; i++)
> + len += scnprintf(buf + len, PAGE_SIZE - len, "%s\n",
> + F2FS_OPTION(sbi).extensions[i]);
> +
> + len += scnprintf(buf + len, PAGE_SIZE - len,
> + "nocompress extension:\n");
> + for (i = 0; i < F2FS_OPTION(sbi).nocompress_ext_cnt; i++)
> + len += scnprintf(buf + len, PAGE_SIZE - len, "%s\n",
> + F2FS_OPTION(sbi).noextensions[i]);
I don't think this is acceptable in sysfs.
> + f2fs_up_read(&sbi->sb_lock);
> + return len;
> + }
> #endif
>
> if (!strcmp(a->attr.name, "gc_segment_mode"))
> @@ -446,6 +468,35 @@ static ssize_t __sbi_store(struct f2fs_attr *a,
> return ret ? ret : count;
> }
>
> +#ifdef CONFIG_F2FS_FS_COMPRESSION
> + if (!strcmp(a->attr.name, "compress_extension")) {
> + char *name = strim((char *)buf);
> + bool set = true, cmpr;
> +
> + if (!strncmp(name, "[c]", 3))
> + cmpr = true;
> + else if (!strncmp(name, "[n]", 3))
> + cmpr = false;
> + else
> + return -EINVAL;
> +
> + name += 3;
> +
> + if (*name == '!') {
> + name++;
> + set = false;
> + }
> +
> + if (!strlen(name) || strlen(name) >= F2FS_EXTENSION_LEN)
> + return -EINVAL;
> +
> + f2fs_down_write(&sbi->sb_lock);
> + ret = f2fs_update_compress_extension(sbi, name, cmpr, set);
> + f2fs_up_write(&sbi->sb_lock);
> + return ret ? ret : count;
> + }
> +#endif
> +
> if (!strcmp(a->attr.name, "ckpt_thread_ioprio")) {
> const char *name = strim((char *)buf);
> struct ckpt_req_control *cprc = &sbi->cprc_info;
> @@ -785,15 +836,16 @@ static ssize_t f2fs_sbi_store(struct f2fs_attr *a,
> const char *buf, size_t count)
> {
> ssize_t ret;
> - bool gc_entry = (!strcmp(a->attr.name, "gc_urgent") ||
> - a->struct_type == GC_THREAD);
> + bool need_lock = (!strcmp(a->attr.name, "gc_urgent") ||
> + a->struct_type == GC_THREAD ||
> + a->struct_type == MOUNT_INFO);
>
> - if (gc_entry) {
> + if (need_lock) {
> if (!down_read_trylock(&sbi->sb->s_umount))
> return -EAGAIN;
> }
> ret = __sbi_store(a, sbi, buf, count);
> - if (gc_entry)
> + if (need_lock)
> up_read(&sbi->sb->s_umount);
>
> return ret;
> @@ -942,6 +994,9 @@ static struct f2fs_attr f2fs_attr_##name = __ATTR(name, 0444, name##_show, NULL)
> #define ATGC_INFO_RW_ATTR(name, elname) \
> F2FS_RW_ATTR(ATGC_INFO, atgc_management, name, elname)
>
> +#define MOUNT_INFO_RW_ATTR(name, elname) \
> + F2FS_RW_ATTR(MOUNT_INFO, f2fs_mount_info, name, elname)
> +
> /* GC_THREAD ATTR */
> GC_THREAD_RW_ATTR(gc_urgent_sleep_time, urgent_sleep_time);
> GC_THREAD_RW_ATTR(gc_min_sleep_time, min_sleep_time);
> @@ -1008,6 +1063,7 @@ F2FS_SBI_GENERAL_RW_ATTR(compr_saved_block);
> F2FS_SBI_GENERAL_RW_ATTR(compr_new_inode);
> F2FS_SBI_GENERAL_RW_ATTR(compress_percent);
> F2FS_SBI_GENERAL_RW_ATTR(compress_watermark);
> +MOUNT_INFO_RW_ATTR(compress_extension, extensions);
> #endif
> /* atomic write */
> F2FS_SBI_GENERAL_RO_ATTR(current_atomic_write);
> @@ -1181,6 +1237,7 @@ static struct attribute *f2fs_attrs[] = {
> ATTR_LIST(compr_new_inode),
> ATTR_LIST(compress_percent),
> ATTR_LIST(compress_watermark),
> + ATTR_LIST(compress_extension),
> #endif
> /* For ATGC */
> ATTR_LIST(atgc_candidate_ratio),
> --
> 2.40.1