From 857ac889cce8a486d47874db4d2f9620e7e9e5de Mon Sep 17 00:00:00 2001 From: Lukas Czerner Date: Wed, 27 Oct 2010 21:30:05 -0400 Subject: [PATCH] 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 Signed-off-by: "Theodore Ts'o" --- fs/ext4/ext4.h | 5 +++++ fs/ext4/ialloc.c | 19 +++++++++--------- fs/ext4/super.c | 52 ++++++++++++++++++++++++++++++++++++++++++++++-- 3 files changed, 65 insertions(+), 11 deletions(-) diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 0fe078d368d..4c5fe37b237 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 e428f23215c..87d228aae6b 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 5066537e5a3..c5b890140d0 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: -- 2.20.1