From 3197ebdb130473a92760100cbfe0d7e671838f48 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Tue, 31 Mar 2009 09:10:09 -0400 Subject: [PATCH] ext4: Add sysfs support Add basic sysfs support so that information about the mounted filesystem and various tuning parameters can be accessed via /sys/fs/ext4//*. Signed-off-by: "Theodore Ts'o" --- Documentation/ABI/testing/sysfs-fs-ext4 | 81 ++++++++++ fs/ext4/ext4_sb.h | 2 + fs/ext4/super.c | 207 ++++++++++++++++++++++++ 3 files changed, 290 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-fs-ext4 diff --git a/Documentation/ABI/testing/sysfs-fs-ext4 b/Documentation/ABI/testing/sysfs-fs-ext4 new file mode 100644 index 000000000000..4e79074de282 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-fs-ext4 @@ -0,0 +1,81 @@ +What: /sys/fs/ext4//mb_stats +Date: March 2008 +Contact: "Theodore Ts'o" +Description: + Controls whether the multiblock allocator should + collect statistics, which are shown during the unmount. + 1 means to collect statistics, 0 means not to collect + statistics + +What: /sys/fs/ext4//mb_group_prealloc +Date: March 2008 +Contact: "Theodore Ts'o" +Description: + The multiblock allocator will round up allocation + requests to a multiple of this tuning parameter if the + stripe size is not set in the ext4 superblock + +What: /sys/fs/ext4//mb_max_to_scan +Date: March 2008 +Contact: "Theodore Ts'o" +Description: + The maximum number of extents the multiblock allocator + will search to find the best extent + +What: /sys/fs/ext4//mb_min_to_scan +Date: March 2008 +Contact: "Theodore Ts'o" +Description: + The minimum number of extents the multiblock allocator + will search to find the best extent + +What: /sys/fs/ext4//mb_order2_req +Date: March 2008 +Contact: "Theodore Ts'o" +Description: + Tuning parameter which controls the minimum size for + requests (as a power of 2) where the buddy cache is + used + +What: /sys/fs/ext4//mb_stream_req +Date: March 2008 +Contact: "Theodore Ts'o" +Description: + Files which have fewer blocks than this tunable + parameter will have their blocks allocated out of a + block group specific preallocation pool, so that small + files are packed closely together. Each large file + will have its blocks allocated out of its own unique + preallocation pool. + +What: /sys/fs/ext4//inode_readahead +Date: March 2008 +Contact: "Theodore Ts'o" +Description: + Tuning parameter which controls the maximum number of + inode table blocks that ext4's inode table readahead + algorithm will pre-read into the buffer cache + +What: /sys/fs/ext4//delayed_allocation_blocks +Date: March 2008 +Contact: "Theodore Ts'o" +Description: + This file is read-only and shows the number of blocks + that are dirty in the page cache, but which do not + have their location in the filesystem allocated yet. + +What: /sys/fs/ext4//lifetime_write_kbytes +Date: March 2008 +Contact: "Theodore Ts'o" +Description: + This file is read-only and shows the number of kilobytes + of data that have been written to this filesystem since it was + created. + +What: /sys/fs/ext4//session_write_kbytes +Date: March 2008 +Contact: "Theodore Ts'o" +Description: + This file is read-only and shows the number of + kilobytes of data that have been written to this + filesystem since it was mounted. diff --git a/fs/ext4/ext4_sb.h b/fs/ext4/ext4_sb.h index 50ab1169c378..57b71fefbccf 100644 --- a/fs/ext4/ext4_sb.h +++ b/fs/ext4/ext4_sb.h @@ -64,6 +64,8 @@ struct ext4_sb_info { struct percpu_counter s_dirtyblocks_counter; struct blockgroup_lock *s_blockgroup_lock; struct proc_dir_entry *s_proc; + struct kobject s_kobj; + struct completion s_kobj_unregister; /* Journaling */ struct inode *s_journal_inode; diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 30fc27cdf8fc..2883d4318c22 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -35,6 +35,7 @@ #include #include #include +#include #include #include #include @@ -48,6 +49,7 @@ #include "group.h" struct proc_dir_entry *ext4_proc_root; +static struct kset *ext4_kset; static int ext4_load_journal(struct super_block *, struct ext4_super_block *, unsigned long journal_devnum); @@ -580,6 +582,7 @@ static void ext4_put_super(struct super_block *sb) remove_proc_entry("inode_readahead_blks", sbi->s_proc); remove_proc_entry(sb->s_id, ext4_proc_root); } + kobject_del(&sbi->s_kobj); for (i = 0; i < sbi->s_gdb_count; i++) brelse(sbi->s_group_desc[i]); @@ -615,6 +618,16 @@ static void ext4_put_super(struct super_block *sb) ext4_blkdev_remove(sbi); } sb->s_fs_info = NULL; + /* + * Now that we are completely done shutting down the + * superblock, we need to actually destroy the kobject. + */ + unlock_kernel(); + unlock_super(sb); + kobject_put(&sbi->s_kobj); + wait_for_completion(&sbi->s_kobj_unregister); + lock_super(sb); + lock_kernel(); kfree(sbi->s_blockgroup_lock); kfree(sbi); return; @@ -1464,6 +1477,11 @@ set_qf_format: return 0; if (option < 0 || option > (1 << 30)) return 0; + if (option & (option - 1)) { + printk(KERN_ERR "EXT4-fs: inode_readahead_blks" + " must be a power of 2\n"); + return 0; + } sbi->s_inode_readahead_blks = option; break; case Opt_journal_ioprio: @@ -1992,6 +2010,181 @@ static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi) return 0; } +/* sysfs supprt */ + +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); + int offset; +}; + +static int parse_strtoul(const char *buf, + unsigned long max, unsigned long *value) +{ + char *endp; + + while (*buf && isspace(*buf)) + buf++; + *value = simple_strtoul(buf, &endp, 0); + while (*endp && isspace(*endp)) + endp++; + if (*endp || *value > max) + return -EINVAL; + + return 0; +} + +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) percpu_counter_sum(&sbi->s_dirtyblocks_counter)); +} + +static ssize_t session_write_kbytes_show(struct ext4_attr *a, + struct ext4_sb_info *sbi, char *buf) +{ + struct super_block *sb = sbi->s_buddy_cache->i_sb; + + return snprintf(buf, PAGE_SIZE, "%lu\n", + (part_stat_read(sb->s_bdev->bd_part, sectors[1]) - + sbi->s_sectors_written_start) >> 1); +} + +static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a, + struct ext4_sb_info *sbi, char *buf) +{ + struct super_block *sb = sbi->s_buddy_cache->i_sb; + + return snprintf(buf, PAGE_SIZE, "%llu\n", + sbi->s_kbytes_written + + ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) - + EXT4_SB(sb)->s_sectors_written_start) >> 1)); +} + +static ssize_t inode_readahead_blks_store(struct ext4_attr *a, + struct ext4_sb_info *sbi, + const char *buf, size_t count) +{ + unsigned long t; + + if (parse_strtoul(buf, 0x40000000, &t)) + return -EINVAL; + + /* inode_readahead_blks must be a power of 2 */ + if (t & (t-1)) + return -EINVAL; + + sbi->s_inode_readahead_blks = t; + 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->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->offset); + unsigned long t; + + if (parse_strtoul(buf, 0xffffffff, &t)) + return -EINVAL; + *ui = t; + return count; +} + +#define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \ +static struct ext4_attr ext4_attr_##_name = { \ + .attr = {.name = __stringify(_name), .mode = _mode }, \ + .show = _show, \ + .store = _store, \ + .offset = offsetof(struct ext4_sb_info, _elname), \ +} +#define EXT4_ATTR(name, mode, show, store) \ +static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store) + +#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) \ + EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname) +#define ATTR_LIST(name) &ext4_attr_##name.attr + +EXT4_RO_ATTR(delayed_allocation_blocks); +EXT4_RO_ATTR(session_write_kbytes); +EXT4_RO_ATTR(lifetime_write_kbytes); +EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show, + inode_readahead_blks_store, s_inode_readahead_blks); +EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats); +EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan); +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); + +static struct attribute *ext4_attrs[] = { + ATTR_LIST(delayed_allocation_blocks), + ATTR_LIST(session_write_kbytes), + ATTR_LIST(lifetime_write_kbytes), + ATTR_LIST(inode_readahead_blks), + ATTR_LIST(mb_stats), + ATTR_LIST(mb_max_to_scan), + ATTR_LIST(mb_min_to_scan), + ATTR_LIST(mb_order2_req), + ATTR_LIST(mb_stream_req), + ATTR_LIST(mb_group_prealloc), + 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; +} + +static ssize_t ext4_attr_store(struct kobject *kobj, + struct attribute *attr, + const char *buf, size_t len) +{ + 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->store ? a->store(a, sbi, buf, len) : 0; +} + +static void ext4_sb_release(struct kobject *kobj) +{ + struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info, + s_kobj); + complete(&sbi->s_kobj_unregister); +} + + +static struct sysfs_ops ext4_attr_ops = { + .show = ext4_attr_show, + .store = ext4_attr_store, +}; + +static struct kobj_type ext4_ktype = { + .default_attrs = ext4_attrs, + .sysfs_ops = &ext4_attr_ops, + .release = ext4_sb_release, +}; + static int ext4_fill_super(struct super_block *sb, void *data, int silent) __releases(kernel_lock) __acquires(kernel_lock) @@ -2575,6 +2768,16 @@ no_journal: goto failed_mount4; } + sbi->s_kobj.kset = ext4_kset; + init_completion(&sbi->s_kobj_unregister); + err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL, + "%s", sb->s_id); + if (err) { + ext4_mb_release(sb); + ext4_ext_release(sb); + goto failed_mount4; + }; + /* * akpm: core read_super() calls in here with the superblock locked. * That deadlocks, because orphan cleanup needs to lock the superblock @@ -3734,6 +3937,9 @@ static int __init init_ext4_fs(void) { int err; + ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj); + if (!ext4_kset) + return -ENOMEM; ext4_proc_root = proc_mkdir("fs/ext4", NULL); err = init_ext4_mballoc(); if (err) @@ -3775,6 +3981,7 @@ static void __exit exit_ext4_fs(void) exit_ext4_xattr(); exit_ext4_mballoc(); remove_proc_entry("fs/ext4", NULL); + kset_unregister(ext4_kset); } MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others"); -- 2.34.1