[PATCH] f2fs: add reserved blocks for root user
From: Jaegeuk Kim
Date: Wed Dec 27 2017 - 21:19:34 EST
This patch allows root to reserve some blocks via mount option.
"-o reserve_root=N" means N x 4KB-sized blocks for root only.
Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
---
fs/f2fs/f2fs.h | 25 ++++++++++++++++++++-----
fs/f2fs/super.c | 24 ++++++++++++++++++++++--
fs/f2fs/sysfs.c | 5 ++++-
3 files changed, 46 insertions(+), 8 deletions(-)
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 5bcd530dbae0..e2d859672147 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -95,6 +95,7 @@ extern char *fault_name[FAULT_MAX];
#define F2FS_MOUNT_PRJQUOTA 0x00200000
#define F2FS_MOUNT_QUOTA 0x00400000
#define F2FS_MOUNT_INLINE_XATTR_SIZE 0x00800000
+#define F2FS_MOUNT_RESERVE_ROOT 0x01000000
#define clear_opt(sbi, option) ((sbi)->mount_opt.opt &= ~F2FS_MOUNT_##option)
#define set_opt(sbi, option) ((sbi)->mount_opt.opt |= F2FS_MOUNT_##option)
@@ -1557,6 +1558,12 @@ static inline bool f2fs_has_xattr_block(unsigned int ofs)
return ofs == XATTR_NODE_OFFSET;
}
+static inline block_t reserve_root_limit(struct f2fs_sb_info *sbi)
+{
+ /* limit is 0.2% */
+ return (sbi->user_block_count << 1) / 100;
+}
+
static inline void f2fs_i_blocks_write(struct inode *, block_t, bool, bool);
static inline int inc_valid_block_count(struct f2fs_sb_info *sbi,
struct inode *inode, blkcnt_t *count)
@@ -1584,13 +1591,18 @@ static inline int inc_valid_block_count(struct f2fs_sb_info *sbi,
spin_lock(&sbi->stat_lock);
sbi->total_valid_block_count += (block_t)(*count);
- avail_user_block_count = sbi->user_block_count -
- sbi->current_reserved_blocks;
+ avail_user_block_count = sbi->user_block_count;
+
+ if (!(test_opt(sbi, RESERVE_ROOT) && capable(CAP_SYS_RESOURCE)))
+ avail_user_block_count -= sbi->current_reserved_blocks;
+
if (unlikely(sbi->total_valid_block_count > avail_user_block_count)) {
diff = sbi->total_valid_block_count - avail_user_block_count;
+ if (diff > *count)
+ diff = *count;
*count -= diff;
release = diff;
- sbi->total_valid_block_count = avail_user_block_count;
+ sbi->total_valid_block_count -= diff;
if (!*count) {
spin_unlock(&sbi->stat_lock);
percpu_counter_sub(&sbi->alloc_valid_block_count, diff);
@@ -1780,8 +1792,11 @@ static inline int inc_valid_node_count(struct f2fs_sb_info *sbi,
spin_lock(&sbi->stat_lock);
valid_block_count = sbi->total_valid_block_count + 1;
- if (unlikely(valid_block_count + sbi->current_reserved_blocks >
- sbi->user_block_count)) {
+
+ if (!(test_opt(sbi, RESERVE_ROOT) && capable(CAP_SYS_RESOURCE)))
+ valid_block_count += sbi->current_reserved_blocks;
+
+ if (unlikely(valid_block_count > sbi->user_block_count)) {
spin_unlock(&sbi->stat_lock);
goto enospc;
}
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index cb876d905ca5..a19e9f7bd908 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -107,6 +107,7 @@ enum {
Opt_noextent_cache,
Opt_noinline_data,
Opt_data_flush,
+ Opt_reserve_root,
Opt_mode,
Opt_io_size_bits,
Opt_fault_injection,
@@ -157,6 +158,7 @@ static match_table_t f2fs_tokens = {
{Opt_noextent_cache, "noextent_cache"},
{Opt_noinline_data, "noinline_data"},
{Opt_data_flush, "data_flush"},
+ {Opt_reserve_root, "reserve_root=%u"},
{Opt_mode, "mode=%s"},
{Opt_io_size_bits, "io_bits=%u"},
{Opt_fault_injection, "fault_injection=%u"},
@@ -488,6 +490,14 @@ static int parse_options(struct super_block *sb, char *options)
case Opt_data_flush:
set_opt(sbi, DATA_FLUSH);
break;
+ case Opt_reserve_root:
+ if (args->from && match_int(args, &arg))
+ return -EINVAL;
+ if (sbi->current_reserved_blocks > arg)
+ return -EINVAL;
+ sbi->current_reserved_blocks = arg;
+ set_opt(sbi, RESERVE_ROOT);
+ break;
case Opt_mode:
name = match_strdup(&args[0]);
@@ -1006,6 +1016,8 @@ static int f2fs_statfs(struct dentry *dentry, struct kstatfs *buf)
buf->f_blocks = total_count - start_count;
buf->f_bfree = user_block_count - valid_user_blocks(sbi) + ovp_count;
+ if (test_opt(sbi, RESERVE_ROOT))
+ buf->f_bfree += sbi->current_reserved_blocks;
buf->f_bavail = user_block_count - valid_user_blocks(sbi) -
sbi->current_reserved_blocks;
@@ -1136,6 +1148,9 @@ static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
else if (test_opt(sbi, LFS))
seq_puts(seq, "lfs");
seq_printf(seq, ",active_logs=%u", sbi->active_logs);
+ if (test_opt(sbi, RESERVE_ROOT))
+ seq_printf(seq, ",reserve_root=%u",
+ sbi->current_reserved_blocks);
if (F2FS_IO_SIZE_BITS(sbi))
seq_printf(seq, ",io_size=%uKB", F2FS_IO_SIZE_KB(sbi));
#ifdef CONFIG_F2FS_FAULT_INJECTION
@@ -2569,8 +2584,13 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
le64_to_cpu(sbi->ckpt->valid_block_count);
sbi->last_valid_block_count = sbi->total_valid_block_count;
sbi->reserved_blocks = 0;
- sbi->current_reserved_blocks = 0;
-
+ if (test_opt(sbi, RESERVE_ROOT) &&
+ sbi->current_reserved_blocks > reserve_root_limit(sbi)) {
+ sbi->current_reserved_blocks = reserve_root_limit(sbi);
+ f2fs_msg(sb, KERN_INFO,
+ "Reduce reserved blocks for root = %u\n",
+ sbi->current_reserved_blocks);
+ }
for (i = 0; i < NR_INODE_TYPE; i++) {
INIT_LIST_HEAD(&sbi->inode_list[i]);
spin_lock_init(&sbi->inode_lock[i]);
diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
index 987b2736348c..33e159491b48 100644
--- a/fs/f2fs/sysfs.c
+++ b/fs/f2fs/sysfs.c
@@ -162,7 +162,10 @@ static ssize_t f2fs_sbi_store(struct f2fs_attr *a,
#endif
if (a->struct_type == RESERVED_BLOCKS) {
spin_lock(&sbi->stat_lock);
- if (t > (unsigned long)sbi->user_block_count) {
+ if (t > (unsigned long)sbi->user_block_count ||
+ (test_opt(sbi, RESERVE_ROOT) &&
+ (t < sbi->current_reserved_blocks ||
+ t > reserve_root_limit(sbi)))) {
spin_unlock(&sbi->stat_lock);
return -EINVAL;
}
--
2.15.0.531.g2ccb3012c9-goog