2009-06-23 08:27:59

by Akira Fujita

[permalink] [raw]
Subject: [RFC][PATCH 7/7]ext4: Add EXT4_IOC_PRINT_INODE_ARULE for debug inode preferred range of blocks

ext4: Add EXT4_IOC_PRINT_INODE_ARULE for debug inode preferred range of blocks

From: Akira Fujita <[email protected]>

# This is a debug ioctl for inode preferred range of blocks.

EXT4_IOC_PRINT_INODE_ARULE ioctl prints the information of
preferred block allocation for specified inode to syslog.

#define EXT4_IOC_PRINT_INODE_ARULE _IO('f', 20 )

This information consist of following four entries.
- inode number (e.g. ino=11)
- start physical offset of this rule
- block length this rule covers
- flag (0: mandatory, 1: advisory)

e.g. ARULE: ino=11 start=6000 len=1000 flag=0

The above means the inode (ino=11) is set preferred block allocation
from 6000 to 6999 with mandatory.
Therefore block allocator is forced to use blocks from 6000 to 6999
and if could not use this range, return -ENOSPC.

Note: Preferred block allocation is disabled when inode reference
counter is 0 or umount FS.


Signed-off-by: Akira Fujita <[email protected]>
Signed-off-by: Kazuya Mio <[email protected]>
---
fs/ext4/ext4.h | 2 ++
fs/ext4/ioctl.c | 5 +++++
fs/ext4/mballoc.c | 20 ++++++++++++++++++++
3 files changed, 27 insertions(+), 0 deletions(-)

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 4ed4b27..4e94960 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -363,6 +363,7 @@ struct ext4_new_group_data {
#define EXT4_IOC_CLR_GLOBAL_ALLOC_RULE _IOW('f', 17, struct ext4_alloc_rule)
#define EXT4_IOC_ADD_INODE_ALLOC_RULE _IOW('f', 18, struct ext4_alloc_rule)
#define EXT4_IOC_PRINT_GLOBAL_ARULE _IO('f', 19)
+#define EXT4_IOC_PRINT_INODE_ARULE _IO('f', 20)

/*
* ioctl commands in 32 bit emulation
@@ -1406,6 +1407,7 @@ extern int ext4_mb_add_inode_arule(struct inode *inode,
extern void ext4_mb_del_inode_arule(struct inode *inode);
extern void ext4_mb_dec_inode_arule(struct inode *inode, unsigned int len);
extern void ext4_mb_print_global_arule(struct inode *inode);
+extern void ext4_mb_print_inode_arule(struct inode *inode);

/* inode.c */
int ext4_forget(handle_t *handle, int is_metadata, struct inode *inode,
diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index 323e3d2..9808dd4 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -323,6 +323,11 @@ setversion_out:
return 0;
}

+ case EXT4_IOC_PRINT_INODE_ARULE: {
+ ext4_mb_print_inode_arule(inode);
+ return 0;
+ }
+
case EXT4_IOC_GROUP_ADD: {
struct ext4_new_group_data input;
struct super_block *sb = inode->i_sb;
diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index cd5b833..bfe633e 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -5859,3 +5859,23 @@ void ext4_mb_print_global_arule(struct inode *inode)

return;
}
+
+void ext4_mb_print_inode_arule(struct inode *inode)
+{
+ struct ext4_inode_info *ei = EXT4_I(inode);
+ struct ext4_alloc_rule *arule = NULL;
+
+ if (ei->i_alloc_rule == NULL)
+ printk(KERN_ERR "ARULE: ino=%lu alloc_rule is empty\n",
+ inode->i_ino);
+ else {
+ arule = &(ei->i_alloc_rule)->alloc_rule;
+ printk(KERN_ERR "ARULE: ino=%lu start=%llu len=%llu "
+ "flag=%u\n", inode->i_ino,
+ (ext4_fsblk_t)arule->start,
+ (ext4_fsblk_t)arule->len,
+ (unsigned)arule->alloc_flag);
+ }
+
+ return;
+}