From 76d33bca5581b1dd5c3157fa168db849a784ada4 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Wed, 23 Sep 2015 12:45:17 -0400 Subject: [PATCH] ext4: refactor sysfs support code Make the code more easily extensible as well as taking up less compiled space. Signed-off-by: Theodore Ts'o --- fs/ext4/sysfs.c | 261 ++++++++++++++++++++++++------------------------ 1 file changed, 128 insertions(+), 133 deletions(-) diff --git a/fs/ext4/sysfs.c b/fs/ext4/sysfs.c index 9fdc21b9b265..87ac08964683 100644 --- a/fs/ext4/sysfs.c +++ b/fs/ext4/sysfs.c @@ -15,37 +15,35 @@ #include "ext4.h" #include "ext4_jbd2.h" +typedef enum { + attr_noop, + attr_delayed_allocation_blocks, + attr_session_write_kbytes, + attr_lifetime_write_kbytes, + attr_reserved_clusters, + attr_inode_readahead, + attr_trigger_test_error, + attr_feature, + attr_pointer_ui, + attr_pointer_atomic, +} attr_id_t; + +typedef enum { + ptr_explicit, + ptr_ext4_sb_info_offset, + ptr_ext4_super_block_offset, +} attr_ptr_t; + struct ext4_attr { struct attribute attr; - ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *); - ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *, - const char *, size_t); + short attr_id; + short attr_ptr; union { int offset; - int deprecated_val; + void *explicit_ptr; } u; }; -static int parse_strtoull(const char *buf, - unsigned long long max, unsigned long long *value) -{ - int ret; - - ret = kstrtoull(skip_spaces(buf), 0, value); - if (!ret && *value > max) - ret = -EINVAL; - return ret; -} - -static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a, - struct ext4_sb_info *sbi, - char *buf) -{ - return snprintf(buf, PAGE_SIZE, "%llu\n", - (s64) EXT4_C2B(sbi, - percpu_counter_sum(&sbi->s_dirtyclusters_counter))); -} - static ssize_t session_write_kbytes_show(struct ext4_attr *a, struct ext4_sb_info *sbi, char *buf) { @@ -89,46 +87,6 @@ static ssize_t inode_readahead_blks_store(struct ext4_attr *a, return count; } -static ssize_t sbi_ui_show(struct ext4_attr *a, - struct ext4_sb_info *sbi, char *buf) -{ - unsigned int *ui = (unsigned int *) (((char *) sbi) + a->u.offset); - - return snprintf(buf, PAGE_SIZE, "%u\n", *ui); -} - -static ssize_t sbi_ui_store(struct ext4_attr *a, - struct ext4_sb_info *sbi, - const char *buf, size_t count) -{ - unsigned int *ui = (unsigned int *) (((char *) sbi) + a->u.offset); - unsigned long t; - int ret; - - ret = kstrtoul(skip_spaces(buf), 0, &t); - if (ret) - return ret; - *ui = t; - return count; -} - -static ssize_t es_ui_show(struct ext4_attr *a, - struct ext4_sb_info *sbi, char *buf) -{ - - unsigned int *ui = (unsigned int *) (((char *) sbi->s_es) + - a->u.offset); - - return snprintf(buf, PAGE_SIZE, "%u\n", *ui); -} - -static ssize_t reserved_clusters_show(struct ext4_attr *a, - struct ext4_sb_info *sbi, char *buf) -{ - return snprintf(buf, PAGE_SIZE, "%llu\n", - (unsigned long long) atomic64_read(&sbi->s_resv_clusters)); -} - static ssize_t reserved_clusters_store(struct ext4_attr *a, struct ext4_sb_info *sbi, const char *buf, size_t count) @@ -136,11 +94,10 @@ static ssize_t reserved_clusters_store(struct ext4_attr *a, unsigned long long val; ext4_fsblk_t clusters = (ext4_blocks_count(sbi->s_es) >> sbi->s_cluster_bits); + int ret; - if (parse_strtoull(buf, -1ULL, &val)) - return -EINVAL; - - if (val >= clusters) + ret = kstrtoull(skip_spaces(buf), 0, &val); + if (!ret || val >= clusters) return -EINVAL; atomic64_set(&sbi->s_resv_clusters, val); @@ -164,60 +121,51 @@ static ssize_t trigger_test_error(struct ext4_attr *a, return count; } -static ssize_t sbi_deprecated_show(struct ext4_attr *a, - struct ext4_sb_info *sbi, char *buf) -{ - return snprintf(buf, PAGE_SIZE, "%d\n", a->u.deprecated_val); +#define EXT4_ATTR(_name,_mode,_id) \ +static struct ext4_attr ext4_attr_##_name = { \ + .attr = {.name = __stringify(_name), .mode = _mode }, \ + .attr_id = attr_##_id, \ } -#define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \ +#define EXT4_ATTR_FUNC(_name,_mode) EXT4_ATTR(_name,_mode,_name) + +#define EXT4_ATTR_FEATURE(_name) EXT4_ATTR(_name, 0444, feature) + +#define EXT4_ATTR_OFFSET(_name,_mode,_id,_struct,_elname) \ static struct ext4_attr ext4_attr_##_name = { \ .attr = {.name = __stringify(_name), .mode = _mode }, \ - .show = _show, \ - .store = _store, \ + .attr_id = attr_##_id, \ + .attr_ptr = ptr_##_struct##_offset, \ .u = { \ - .offset = offsetof(struct ext4_sb_info, _elname),\ + .offset = offsetof(struct _struct, _elname),\ }, \ } -#define EXT4_ATTR_OFFSET_ES(_name,_mode,_show,_store,_elname) \ -static struct ext4_attr ext4_attr_##_name = { \ - .attr = {.name = __stringify(_name), .mode = _mode }, \ - .show = _show, \ - .store = _store, \ - .u = { \ - .offset = offsetof(struct ext4_super_block, _elname), \ - }, \ -} - -#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_RO_ATTR_ES_UI(_name,_elname) \ + EXT4_ATTR_OFFSET(_name, 0444, pointer_ui, ext4_super_block, _elname) -#define EXT4_RO_ATTR_ES_UI(name, elname) \ - EXT4_ATTR_OFFSET_ES(name, 0444, es_ui_show, NULL, elname) -#define EXT4_RW_ATTR_SBI_UI(name, elname) \ - EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname) +#define EXT4_RW_ATTR_SBI_UI(_name,_elname) \ + EXT4_ATTR_OFFSET(_name, 0644, pointer_ui, ext4_sb_info, _elname) -#define ATTR_LIST(name) &ext4_attr_##name.attr -#define EXT4_DEPRECATED_ATTR(_name, _val) \ +#define EXT4_ATTR_PTR(_name,_mode,_id,_ptr) \ static struct ext4_attr ext4_attr_##_name = { \ - .attr = {.name = __stringify(_name), .mode = 0444 }, \ - .show = sbi_deprecated_show, \ + .attr = {.name = __stringify(_name), .mode = _mode }, \ + .attr_id = attr_##_id, \ + .attr_ptr = ptr_explicit, \ .u = { \ - .deprecated_val = _val, \ + .explicit_ptr = _ptr, \ }, \ } -EXT4_RO_ATTR(delayed_allocation_blocks); -EXT4_RO_ATTR(session_write_kbytes); -EXT4_RO_ATTR(lifetime_write_kbytes); -EXT4_RW_ATTR(reserved_clusters); -EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show, - inode_readahead_blks_store, s_inode_readahead_blks); +#define ATTR_LIST(name) &ext4_attr_##name.attr + +EXT4_ATTR_FUNC(delayed_allocation_blocks, 0444); +EXT4_ATTR_FUNC(session_write_kbytes, 0444); +EXT4_ATTR_FUNC(lifetime_write_kbytes, 0444); +EXT4_ATTR_FUNC(reserved_clusters, 0644); + +EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, inode_readahead, + ext4_sb_info, s_inode_readahead_blks); EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal); EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats); EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan); @@ -225,9 +173,8 @@ EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan); EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs); EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request); EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc); -EXT4_DEPRECATED_ATTR(max_writeback_mb_bump, 128); EXT4_RW_ATTR_SBI_UI(extent_max_zeroout_kb, s_extent_max_zeroout_kb); -EXT4_ATTR(trigger_fs_error, 0200, NULL, trigger_test_error); +EXT4_ATTR(trigger_fs_error, 0200, trigger_test_error); EXT4_RW_ATTR_SBI_UI(err_ratelimit_interval_ms, s_err_ratelimit_state.interval); EXT4_RW_ATTR_SBI_UI(err_ratelimit_burst, s_err_ratelimit_state.burst); EXT4_RW_ATTR_SBI_UI(warning_ratelimit_interval_ms, s_warning_ratelimit_state.interval); @@ -238,6 +185,9 @@ EXT4_RO_ATTR_ES_UI(errors_count, s_error_count); EXT4_RO_ATTR_ES_UI(first_error_time, s_first_error_time); EXT4_RO_ATTR_ES_UI(last_error_time, s_last_error_time); +static unsigned int old_bump_val = 128; +EXT4_ATTR_PTR(max_writeback_mb_bump, 0444, pointer_ui, &old_bump_val); + static struct attribute *ext4_attrs[] = { ATTR_LIST(delayed_allocation_blocks), ATTR_LIST(session_write_kbytes), @@ -267,10 +217,10 @@ static struct attribute *ext4_attrs[] = { }; /* Features this copy of ext4 supports */ -EXT4_INFO_ATTR(lazy_itable_init); -EXT4_INFO_ATTR(batched_discard); -EXT4_INFO_ATTR(meta_bg_resize); -EXT4_INFO_ATTR(encryption); +EXT4_ATTR_FEATURE(lazy_itable_init); +EXT4_ATTR_FEATURE(batched_discard); +EXT4_ATTR_FEATURE(meta_bg_resize); +EXT4_ATTR_FEATURE(encryption); static struct attribute *ext4_feat_attrs[] = { ATTR_LIST(lazy_itable_init), @@ -280,14 +230,56 @@ static struct attribute *ext4_feat_attrs[] = { NULL, }; +static void *calc_ptr(struct ext4_attr *a, struct ext4_sb_info *sbi) +{ + switch (a->attr_ptr) { + case ptr_explicit: + return a->u.explicit_ptr; + case ptr_ext4_sb_info_offset: + return (void *) (((char *) sbi) + a->u.offset); + case ptr_ext4_super_block_offset: + return (void *) (((char *) sbi->s_es) + a->u.offset); + } + return NULL; +} + static ssize_t ext4_attr_show(struct kobject *kobj, struct attribute *attr, char *buf) { struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info, s_kobj); struct ext4_attr *a = container_of(attr, struct ext4_attr, attr); - - return a->show ? a->show(a, sbi, buf) : 0; + void *ptr = calc_ptr(a, sbi); + + switch (a->attr_id) { + case attr_delayed_allocation_blocks: + return snprintf(buf, PAGE_SIZE, "%llu\n", + (s64) EXT4_C2B(sbi, + percpu_counter_sum(&sbi->s_dirtyclusters_counter))); + case attr_session_write_kbytes: + return session_write_kbytes_show(a, sbi, buf); + case attr_lifetime_write_kbytes: + return lifetime_write_kbytes_show(a, sbi, buf); + case attr_reserved_clusters: + return snprintf(buf, PAGE_SIZE, "%llu\n", + (unsigned long long) + atomic64_read(&sbi->s_resv_clusters)); + case attr_inode_readahead: + case attr_pointer_ui: + if (!ptr) + return 0; + return snprintf(buf, PAGE_SIZE, "%u\n", + *((unsigned int *) ptr)); + case attr_pointer_atomic: + if (!ptr) + return 0; + return snprintf(buf, PAGE_SIZE, "%d\n", + atomic_read((atomic_t *) ptr)); + case attr_feature: + return snprintf(buf, PAGE_SIZE, "supported\n"); + } + + return 0; } static ssize_t ext4_attr_store(struct kobject *kobj, @@ -297,8 +289,27 @@ static ssize_t ext4_attr_store(struct kobject *kobj, struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info, s_kobj); struct ext4_attr *a = container_of(attr, struct ext4_attr, attr); + void *ptr = calc_ptr(a, sbi); + unsigned long t; + int ret; - return a->store ? a->store(a, sbi, buf, len) : 0; + switch (a->attr_id) { + case attr_reserved_clusters: + return reserved_clusters_store(a, sbi, buf, len); + case attr_pointer_ui: + if (!ptr) + return 0; + ret = kstrtoul(skip_spaces(buf), 0, &t); + if (ret) + return ret; + *((unsigned int *) ptr) = t; + return len; + case attr_inode_readahead: + return inode_readahead_blks_store(a, sbi, buf, len); + case attr_trigger_test_error: + return trigger_test_error(a, sbi, buf, len); + } + return 0; } static void ext4_sb_release(struct kobject *kobj) @@ -327,25 +338,9 @@ static struct kset ext4_kset = { .kobj = {.ktype = &ext4_ktype}, }; -static ssize_t ext4_feat_show(struct kobject *kobj, - struct attribute *attr, char *buf) -{ - return snprintf(buf, PAGE_SIZE, "supported\n"); -} - -/* - * We can not use ext4_attr_show/store because it relies on the kobject - * being embedded in the ext4_sb_info structure which is definitely not - * true in this case. - */ -static const struct sysfs_ops ext4_feat_ops = { - .show = ext4_feat_show, - .store = NULL, -}; - static struct kobj_type ext4_feat_ktype = { .default_attrs = ext4_feat_attrs, - .sysfs_ops = &ext4_feat_ops, + .sysfs_ops = &ext4_attr_ops, }; static struct kobject ext4_feat = { -- 2.39.2