summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorLukas Czerner <lczerner@redhat.com>2010-10-27 21:30:05 -0400
committerTheodore Ts'o <tytso@mit.edu>2010-10-27 21:30:05 -0400
commit857ac889cce8a486d47874db4d2f9620e7e9e5de (patch)
tree12401895197d819fcbf2335244d91259f4640aa2
parentbfff68738f1cb5c93dab1114634cea02aae9e7ba (diff)
ext4: add interface to advertise ext4 features in sysfs
User-space should have the opportunity to check what features doest ext4 support in each particular copy. This adds easy interface by creating new "features" directory in sys/fs/ext4/. In that directory files advertising feature names can be created. Add lazy_itable_init to the feature list. Signed-off-by: Lukas Czerner <lczerner@redhat.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
-rw-r--r--fs/ext4/ext4.h5
-rw-r--r--fs/ext4/ialloc.c19
-rw-r--r--fs/ext4/super.c52
3 files changed, 65 insertions, 11 deletions
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 0fe078d368d0..4c5fe37b237d 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1574,6 +1574,11 @@ struct ext4_li_request {
unsigned long lr_timeout;
};
+struct ext4_features {
+ struct kobject f_kobj;
+ struct completion f_kobj_unregister;
+};
+
/*
* Function prototypes
*/
diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index e428f23215c0..87d228aae6b0 100644
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -1274,6 +1274,16 @@ extern int ext4_init_inode_table(struct super_block *sb, ext4_group_t group,
ext4_itable_unused_count(sb, gdp)),
sbi->s_inodes_per_block);
+ if ((used_blks < 0) || (used_blks > sbi->s_itb_per_group)) {
+ ext4_error(sb, "Something is wrong with group %u\n"
+ "Used itable blocks: %d"
+ "itable unused count: %u\n",
+ group, used_blks,
+ ext4_itable_unused_count(sb, gdp));
+ ret = 1;
+ goto out;
+ }
+
blk = ext4_inode_table(sb, gdp) + used_blks;
num = sbi->s_itb_per_group - used_blks;
@@ -1283,15 +1293,6 @@ extern int ext4_init_inode_table(struct super_block *sb, ext4_group_t group,
if (ret)
goto err_out;
- if (unlikely(num > EXT4_INODES_PER_GROUP(sb))) {
- ext4_error(sb, "Something is wrong with group %u\n"
- "Used itable blocks: %d"
- "Itable blocks per group: %lu\n",
- group, used_blks, sbi->s_itb_per_group);
- ret = 1;
- goto err_out;
- }
-
/*
* Skip zeroout if the inode table is full. But we set the ZEROED
* flag anyway, because obviously, when it is full it does not need
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 5066537e5a38..c5b890140d01 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -57,6 +57,7 @@ struct proc_dir_entry *ext4_proc_root;
static struct kset *ext4_kset;
struct ext4_lazy_init *ext4_li_info;
struct mutex ext4_li_mtx;
+struct ext4_features *ext4_feat;
static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
unsigned long journal_devnum);
@@ -709,6 +710,7 @@ static void ext4_put_super(struct super_block *sb)
struct ext4_super_block *es = sbi->s_es;
int i, err;
+ ext4_unregister_li_request(sb);
dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
flush_workqueue(sbi->dio_unwritten_wq);
@@ -727,7 +729,6 @@ static void ext4_put_super(struct super_block *sb)
}
del_timer(&sbi->s_err_report);
- ext4_unregister_li_request(sb);
ext4_release_system_zone(sb);
ext4_mb_release(sb);
ext4_ext_release(sb);
@@ -2416,6 +2417,7 @@ static struct ext4_attr ext4_attr_##_name = { \
#define EXT4_ATTR(name, mode, show, store) \
static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
+#define EXT4_INFO_ATTR(name) EXT4_ATTR(name, 0444, NULL, NULL)
#define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
#define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
#define EXT4_RW_ATTR_SBI_UI(name, elname) \
@@ -2452,6 +2454,14 @@ static struct attribute *ext4_attrs[] = {
NULL,
};
+/* Features this copy of ext4 supports */
+EXT4_INFO_ATTR(lazy_itable_init);
+
+static struct attribute *ext4_feat_attrs[] = {
+ ATTR_LIST(lazy_itable_init),
+ NULL,
+};
+
static ssize_t ext4_attr_show(struct kobject *kobj,
struct attribute *attr, char *buf)
{
@@ -2480,7 +2490,6 @@ static void ext4_sb_release(struct kobject *kobj)
complete(&sbi->s_kobj_unregister);
}
-
static const struct sysfs_ops ext4_attr_ops = {
.show = ext4_attr_show,
.store = ext4_attr_store,
@@ -2492,6 +2501,17 @@ static struct kobj_type ext4_ktype = {
.release = ext4_sb_release,
};
+static void ext4_feat_release(struct kobject *kobj)
+{
+ complete(&ext4_feat->f_kobj_unregister);
+}
+
+static struct kobj_type ext4_feat_ktype = {
+ .default_attrs = ext4_feat_attrs,
+ .sysfs_ops = &ext4_attr_ops,
+ .release = ext4_feat_release,
+};
+
/*
* Check whether this filesystem can be mounted based on
* the features present and the RDONLY/RDWR mount requested.
@@ -4720,6 +4740,30 @@ static struct file_system_type ext4_fs_type = {
.fs_flags = FS_REQUIRES_DEV,
};
+int __init ext4_init_feat_adverts(void)
+{
+ struct ext4_features *ef;
+ int ret = -ENOMEM;
+
+ ef = kzalloc(sizeof(struct ext4_features), GFP_KERNEL);
+ if (!ef)
+ goto out;
+
+ ef->f_kobj.kset = ext4_kset;
+ init_completion(&ef->f_kobj_unregister);
+ ret = kobject_init_and_add(&ef->f_kobj, &ext4_feat_ktype, NULL,
+ "features");
+ if (ret) {
+ kfree(ef);
+ goto out;
+ }
+
+ ext4_feat = ef;
+ ret = 0;
+out:
+ return ret;
+}
+
static int __init init_ext4_fs(void)
{
int err;
@@ -4732,6 +4776,9 @@ static int __init init_ext4_fs(void)
if (!ext4_kset)
goto out4;
ext4_proc_root = proc_mkdir("fs/ext4", NULL);
+
+ err = ext4_init_feat_adverts();
+
err = init_ext4_mballoc();
if (err)
goto out3;
@@ -4760,6 +4807,7 @@ out1:
out2:
exit_ext4_mballoc();
out3:
+ kfree(ext4_feat);
remove_proc_entry("fs/ext4", NULL);
kset_unregister(ext4_kset);
out4: