diff --git a/Documentation/filesystems/f2fs.rst b/Documentation/filesystems/f2fs.rst index d294d04c06d0..3a5e309823ba 100644 --- a/Documentation/filesystems/f2fs.rst +++ b/Documentation/filesystems/f2fs.rst @@ -336,6 +336,11 @@ discard_unit=%s Control discard unit, the argument can be "block", "segment" default, it is helpful for large sized SMR or ZNS devices to reduce memory cost by getting rid of fs metadata supports small discard. +memory=%s Control memory mode. This supports "normal" and "low" modes. + "low" mode is introduced to support low memory devices. + Because of the nature of low memory devices, in this mode, f2fs + will try to save memory sometimes by sacrificing performance. + "normal" mode is the default mode and same as before. ======================== ============================================================ Debugfs Entries diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index d3d0b08ae1bc..3e4e06b4e26e 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -156,6 +156,7 @@ struct f2fs_mount_info { int fsync_mode; /* fsync policy */ int fs_mode; /* fs mode: LFS or ADAPTIVE */ int bggc_mode; /* bggc mode: off, on or sync */ + int memory_mode; /* memory mode */ int discard_unit; /* * discard command's offset/size should * be aligned to this unit: block, @@ -1357,6 +1358,13 @@ enum { DISCARD_UNIT_SECTION, /* basic discard unit is section */ }; +enum { + MEMORY_MODE_NORMAL, /* memory mode for normal devices */ + MEMORY_MODE_LOW, /* memory mode for low memry devices */ +}; + + + static inline int f2fs_test_bit(unsigned int nr, char *addr); static inline void f2fs_set_bit(unsigned int nr, char *addr); static inline void f2fs_clear_bit(unsigned int nr, char *addr); @@ -4391,6 +4399,11 @@ static inline bool f2fs_lfs_mode(struct f2fs_sb_info *sbi) return F2FS_OPTION(sbi).fs_mode == FS_MODE_LFS; } +static inline bool f2fs_low_mem_mode(struct f2fs_sb_info *sbi) +{ + return F2FS_OPTION(sbi).memory_mode == MEMORY_MODE_LOW; +} + static inline bool f2fs_may_compress(struct inode *inode) { if (IS_SWAPFILE(inode) || f2fs_is_pinned_file(inode) || diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index 3268d981626a..487a2cac1581 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -160,6 +160,7 @@ enum { Opt_gc_merge, Opt_nogc_merge, Opt_discard_unit, + Opt_memory_mode, Opt_err, }; @@ -236,6 +237,7 @@ static match_table_t f2fs_tokens = { {Opt_gc_merge, "gc_merge"}, {Opt_nogc_merge, "nogc_merge"}, {Opt_discard_unit, "discard_unit=%s"}, + {Opt_memory_mode, "memory=%s"}, {Opt_err, NULL}, }; @@ -1242,6 +1244,22 @@ static int parse_options(struct super_block *sb, char *options, bool is_remount) } kfree(name); break; + case Opt_memory_mode: + name = match_strdup(&args[0]); + if (!name) + return -ENOMEM; + if (!strcmp(name, "normal")) { + F2FS_OPTION(sbi).memory_mode = + MEMORY_MODE_NORMAL; + } else if (!strcmp(name, "low")) { + F2FS_OPTION(sbi).memory_mode = + MEMORY_MODE_LOW; + } else { + kfree(name); + return -EINVAL; + } + kfree(name); + break; default: f2fs_err(sbi, "Unrecognized mount option \"%s\" or missing value", p); @@ -2009,6 +2027,11 @@ static int f2fs_show_options(struct seq_file *seq, struct dentry *root) else if (F2FS_OPTION(sbi).discard_unit == DISCARD_UNIT_SECTION) seq_printf(seq, ",discard_unit=%s", "section"); + if (F2FS_OPTION(sbi).memory_mode == MEMORY_MODE_NORMAL) + seq_printf(seq, ",memory=%s", "normal"); + else if (F2FS_OPTION(sbi).memory_mode == MEMORY_MODE_LOW) + seq_printf(seq, ",memory=%s", "low"); + return 0; } @@ -2030,6 +2053,7 @@ static void default_options(struct f2fs_sb_info *sbi) F2FS_OPTION(sbi).compress_ext_cnt = 0; F2FS_OPTION(sbi).compress_mode = COMPR_MODE_FS; F2FS_OPTION(sbi).bggc_mode = BGGC_MODE_ON; + F2FS_OPTION(sbi).memory_mode = MEMORY_MODE_NORMAL; sbi->sb->s_flags &= ~SB_INLINECRYPT;