Revision e1cbbfa5f5aaf40a1fe70856fac4dfcc33e0e651 authored by Josef Bacik on 17 March 2015, 14:52:28 UTC, committed by Josef Bacik on 17 March 2015, 20:36:35 UTC
We are keeping track of how many extents we need to reserve properly based on the amount we want to write, but we were still incrementing outstanding_extents if we wrote less than what we requested. This isn't quite right since we will be limited to our max extent size. So instead lets do something horrible! Keep track of how many outstanding_extents we reserved, and decrement each time we allocate an extent. If we use our entire reserve make sure to jack up outstanding_extents on the inode so the accounting works out properly. Thanks, Reported-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <jbacik@fb.com>
1 parent 6a3891c
super.c
/*
* fs/logfs/super.c
*
* As should be obvious for Linux kernel code, license is GPLv2
*
* Copyright (c) 2005-2008 Joern Engel <joern@logfs.org>
*
* Generally contains mount/umount code and also serves as a dump area for
* any functions that don't fit elsewhere and neither justify a file of their
* own.
*/
#include "logfs.h"
#include <linux/bio.h>
#include <linux/slab.h>
#include <linux/blkdev.h>
#include <linux/module.h>
#include <linux/mtd/mtd.h>
#include <linux/statfs.h>
#include <linux/buffer_head.h>
static DEFINE_MUTEX(emergency_mutex);
static struct page *emergency_page;
struct page *emergency_read_begin(struct address_space *mapping, pgoff_t index)
{
filler_t *filler = (filler_t *)mapping->a_ops->readpage;
struct page *page;
int err;
page = read_cache_page(mapping, index, filler, NULL);
if (page)
return page;
/* No more pages available, switch to emergency page */
printk(KERN_INFO"Logfs: Using emergency page\n");
mutex_lock(&emergency_mutex);
err = filler(NULL, emergency_page);
if (err) {
mutex_unlock(&emergency_mutex);
printk(KERN_EMERG"Logfs: Error reading emergency page\n");
return ERR_PTR(err);
}
return emergency_page;
}
void emergency_read_end(struct page *page)
{
if (page == emergency_page)
mutex_unlock(&emergency_mutex);
else
page_cache_release(page);
}
static void dump_segfile(struct super_block *sb)
{
struct logfs_super *super = logfs_super(sb);
struct logfs_segment_entry se;
u32 segno;
for (segno = 0; segno < super->s_no_segs; segno++) {
logfs_get_segment_entry(sb, segno, &se);
printk("%3x: %6x %8x", segno, be32_to_cpu(se.ec_level),
be32_to_cpu(se.valid));
if (++segno < super->s_no_segs) {
logfs_get_segment_entry(sb, segno, &se);
printk(" %6x %8x", be32_to_cpu(se.ec_level),
be32_to_cpu(se.valid));
}
if (++segno < super->s_no_segs) {
logfs_get_segment_entry(sb, segno, &se);
printk(" %6x %8x", be32_to_cpu(se.ec_level),
be32_to_cpu(se.valid));
}
if (++segno < super->s_no_segs) {
logfs_get_segment_entry(sb, segno, &se);
printk(" %6x %8x", be32_to_cpu(se.ec_level),
be32_to_cpu(se.valid));
}
printk("\n");
}
}
/*
* logfs_crash_dump - dump debug information to device
*
* The LogFS superblock only occupies part of a segment. This function will
* write as much debug information as it can gather into the spare space.
*/
void logfs_crash_dump(struct super_block *sb)
{
dump_segfile(sb);
}
/*
* FIXME: There should be a reserve for root, similar to ext2.
*/
int logfs_statfs(struct dentry *dentry, struct kstatfs *stats)
{
struct super_block *sb = dentry->d_sb;
struct logfs_super *super = logfs_super(sb);
stats->f_type = LOGFS_MAGIC_U32;
stats->f_bsize = sb->s_blocksize;
stats->f_blocks = super->s_size >> LOGFS_BLOCK_BITS >> 3;
stats->f_bfree = super->s_free_bytes >> sb->s_blocksize_bits;
stats->f_bavail = super->s_free_bytes >> sb->s_blocksize_bits;
stats->f_files = 0;
stats->f_ffree = 0;
stats->f_namelen = LOGFS_MAX_NAMELEN;
return 0;
}
static int logfs_sb_set(struct super_block *sb, void *_super)
{
struct logfs_super *super = _super;
sb->s_fs_info = super;
sb->s_mtd = super->s_mtd;
sb->s_bdev = super->s_bdev;
#ifdef CONFIG_BLOCK
if (sb->s_bdev)
sb->s_bdi = &bdev_get_queue(sb->s_bdev)->backing_dev_info;
#endif
#ifdef CONFIG_MTD
if (sb->s_mtd)
sb->s_bdi = sb->s_mtd->backing_dev_info;
#endif
return 0;
}
static int logfs_sb_test(struct super_block *sb, void *_super)
{
struct logfs_super *super = _super;
struct mtd_info *mtd = super->s_mtd;
if (mtd && sb->s_mtd == mtd)
return 1;
if (super->s_bdev && sb->s_bdev == super->s_bdev)
return 1;
return 0;
}
static void set_segment_header(struct logfs_segment_header *sh, u8 type,
u8 level, u32 segno, u32 ec)
{
sh->pad = 0;
sh->type = type;
sh->level = level;
sh->segno = cpu_to_be32(segno);
sh->ec = cpu_to_be32(ec);
sh->gec = cpu_to_be64(segno);
sh->crc = logfs_crc32(sh, LOGFS_SEGMENT_HEADERSIZE, 4);
}
static void logfs_write_ds(struct super_block *sb, struct logfs_disk_super *ds,
u32 segno, u32 ec)
{
struct logfs_super *super = logfs_super(sb);
struct logfs_segment_header *sh = &ds->ds_sh;
int i;
memset(ds, 0, sizeof(*ds));
set_segment_header(sh, SEG_SUPER, 0, segno, ec);
ds->ds_ifile_levels = super->s_ifile_levels;
ds->ds_iblock_levels = super->s_iblock_levels;
ds->ds_data_levels = super->s_data_levels; /* XXX: Remove */
ds->ds_segment_shift = super->s_segshift;
ds->ds_block_shift = sb->s_blocksize_bits;
ds->ds_write_shift = super->s_writeshift;
ds->ds_filesystem_size = cpu_to_be64(super->s_size);
ds->ds_segment_size = cpu_to_be32(super->s_segsize);
ds->ds_bad_seg_reserve = cpu_to_be32(super->s_bad_seg_reserve);
ds->ds_feature_incompat = cpu_to_be64(super->s_feature_incompat);
ds->ds_feature_ro_compat= cpu_to_be64(super->s_feature_ro_compat);
ds->ds_feature_compat = cpu_to_be64(super->s_feature_compat);
ds->ds_feature_flags = cpu_to_be64(super->s_feature_flags);
ds->ds_root_reserve = cpu_to_be64(super->s_root_reserve);
ds->ds_speed_reserve = cpu_to_be64(super->s_speed_reserve);
journal_for_each(i)
ds->ds_journal_seg[i] = cpu_to_be32(super->s_journal_seg[i]);
ds->ds_magic = cpu_to_be64(LOGFS_MAGIC);
ds->ds_crc = logfs_crc32(ds, sizeof(*ds),
LOGFS_SEGMENT_HEADERSIZE + 12);
}
static int write_one_sb(struct super_block *sb,
struct page *(*find_sb)(struct super_block *sb, u64 *ofs))
{
struct logfs_super *super = logfs_super(sb);
struct logfs_disk_super *ds;
struct logfs_segment_entry se;
struct page *page;
u64 ofs;
u32 ec, segno;
int err;
page = find_sb(sb, &ofs);
if (!page)
return -EIO;
ds = page_address(page);
segno = seg_no(sb, ofs);
logfs_get_segment_entry(sb, segno, &se);
ec = be32_to_cpu(se.ec_level) >> 4;
ec++;
logfs_set_segment_erased(sb, segno, ec, 0);
logfs_write_ds(sb, ds, segno, ec);
err = super->s_devops->write_sb(sb, page);
page_cache_release(page);
return err;
}
int logfs_write_sb(struct super_block *sb)
{
struct logfs_super *super = logfs_super(sb);
int err;
/* First superblock */
err = write_one_sb(sb, super->s_devops->find_first_sb);
if (err)
return err;
/* Last superblock */
err = write_one_sb(sb, super->s_devops->find_last_sb);
if (err)
return err;
return 0;
}
static int ds_cmp(const void *ds0, const void *ds1)
{
size_t len = sizeof(struct logfs_disk_super);
/* We know the segment headers differ, so ignore them */
len -= LOGFS_SEGMENT_HEADERSIZE;
ds0 += LOGFS_SEGMENT_HEADERSIZE;
ds1 += LOGFS_SEGMENT_HEADERSIZE;
return memcmp(ds0, ds1, len);
}
static int logfs_recover_sb(struct super_block *sb)
{
struct logfs_super *super = logfs_super(sb);
struct logfs_disk_super _ds0, *ds0 = &_ds0;
struct logfs_disk_super _ds1, *ds1 = &_ds1;
int err, valid0, valid1;
/* read first superblock */
err = wbuf_read(sb, super->s_sb_ofs[0], sizeof(*ds0), ds0);
if (err)
return err;
/* read last superblock */
err = wbuf_read(sb, super->s_sb_ofs[1], sizeof(*ds1), ds1);
if (err)
return err;
valid0 = logfs_check_ds(ds0) == 0;
valid1 = logfs_check_ds(ds1) == 0;
if (!valid0 && valid1) {
printk(KERN_INFO"First superblock is invalid - fixing.\n");
return write_one_sb(sb, super->s_devops->find_first_sb);
}
if (valid0 && !valid1) {
printk(KERN_INFO"Last superblock is invalid - fixing.\n");
return write_one_sb(sb, super->s_devops->find_last_sb);
}
if (valid0 && valid1 && ds_cmp(ds0, ds1)) {
printk(KERN_INFO"Superblocks don't match - fixing.\n");
return logfs_write_sb(sb);
}
/* If neither is valid now, something's wrong. Didn't we properly
* check them before?!? */
BUG_ON(!valid0 && !valid1);
return 0;
}
static int logfs_make_writeable(struct super_block *sb)
{
int err;
err = logfs_open_segfile(sb);
if (err)
return err;
/* Repair any broken superblock copies */
err = logfs_recover_sb(sb);
if (err)
return err;
/* Check areas for trailing unaccounted data */
err = logfs_check_areas(sb);
if (err)
return err;
/* Do one GC pass before any data gets dirtied */
logfs_gc_pass(sb);
/* after all initializations are done, replay the journal
* for rw-mounts, if necessary */
err = logfs_replay_journal(sb);
if (err)
return err;
return 0;
}
static int logfs_get_sb_final(struct super_block *sb)
{
struct logfs_super *super = logfs_super(sb);
struct inode *rootdir;
int err;
/* root dir */
rootdir = logfs_iget(sb, LOGFS_INO_ROOT);
if (IS_ERR(rootdir))
goto fail;
sb->s_root = d_make_root(rootdir);
if (!sb->s_root)
goto fail;
/* at that point we know that ->put_super() will be called */
super->s_erase_page = alloc_pages(GFP_KERNEL, 0);
if (!super->s_erase_page)
return -ENOMEM;
memset(page_address(super->s_erase_page), 0xFF, PAGE_SIZE);
/* FIXME: check for read-only mounts */
err = logfs_make_writeable(sb);
if (err) {
__free_page(super->s_erase_page);
return err;
}
log_super("LogFS: Finished mounting\n");
return 0;
fail:
iput(super->s_master_inode);
iput(super->s_segfile_inode);
iput(super->s_mapping_inode);
return -EIO;
}
int logfs_check_ds(struct logfs_disk_super *ds)
{
struct logfs_segment_header *sh = &ds->ds_sh;
if (ds->ds_magic != cpu_to_be64(LOGFS_MAGIC))
return -EINVAL;
if (sh->crc != logfs_crc32(sh, LOGFS_SEGMENT_HEADERSIZE, 4))
return -EINVAL;
if (ds->ds_crc != logfs_crc32(ds, sizeof(*ds),
LOGFS_SEGMENT_HEADERSIZE + 12))
return -EINVAL;
return 0;
}
static struct page *find_super_block(struct super_block *sb)
{
struct logfs_super *super = logfs_super(sb);
struct page *first, *last;
first = super->s_devops->find_first_sb(sb, &super->s_sb_ofs[0]);
if (!first || IS_ERR(first))
return NULL;
last = super->s_devops->find_last_sb(sb, &super->s_sb_ofs[1]);
if (!last || IS_ERR(last)) {
page_cache_release(first);
return NULL;
}
if (!logfs_check_ds(page_address(first))) {
page_cache_release(last);
return first;
}
/* First one didn't work, try the second superblock */
if (!logfs_check_ds(page_address(last))) {
page_cache_release(first);
return last;
}
/* Neither worked, sorry folks */
page_cache_release(first);
page_cache_release(last);
return NULL;
}
static int __logfs_read_sb(struct super_block *sb)
{
struct logfs_super *super = logfs_super(sb);
struct page *page;
struct logfs_disk_super *ds;
int i;
page = find_super_block(sb);
if (!page)
return -EINVAL;
ds = page_address(page);
super->s_size = be64_to_cpu(ds->ds_filesystem_size);
super->s_root_reserve = be64_to_cpu(ds->ds_root_reserve);
super->s_speed_reserve = be64_to_cpu(ds->ds_speed_reserve);
super->s_bad_seg_reserve = be32_to_cpu(ds->ds_bad_seg_reserve);
super->s_segsize = 1 << ds->ds_segment_shift;
super->s_segmask = (1 << ds->ds_segment_shift) - 1;
super->s_segshift = ds->ds_segment_shift;
sb->s_blocksize = 1 << ds->ds_block_shift;
sb->s_blocksize_bits = ds->ds_block_shift;
super->s_writesize = 1 << ds->ds_write_shift;
super->s_writeshift = ds->ds_write_shift;
super->s_no_segs = super->s_size >> super->s_segshift;
super->s_no_blocks = super->s_segsize >> sb->s_blocksize_bits;
super->s_feature_incompat = be64_to_cpu(ds->ds_feature_incompat);
super->s_feature_ro_compat = be64_to_cpu(ds->ds_feature_ro_compat);
super->s_feature_compat = be64_to_cpu(ds->ds_feature_compat);
super->s_feature_flags = be64_to_cpu(ds->ds_feature_flags);
journal_for_each(i)
super->s_journal_seg[i] = be32_to_cpu(ds->ds_journal_seg[i]);
super->s_ifile_levels = ds->ds_ifile_levels;
super->s_iblock_levels = ds->ds_iblock_levels;
super->s_data_levels = ds->ds_data_levels;
super->s_total_levels = super->s_ifile_levels + super->s_iblock_levels
+ super->s_data_levels;
page_cache_release(page);
return 0;
}
static int logfs_read_sb(struct super_block *sb, int read_only)
{
struct logfs_super *super = logfs_super(sb);
int ret;
super->s_btree_pool = mempool_create(32, btree_alloc, btree_free, NULL);
if (!super->s_btree_pool)
return -ENOMEM;
btree_init_mempool64(&super->s_shadow_tree.new, super->s_btree_pool);
btree_init_mempool64(&super->s_shadow_tree.old, super->s_btree_pool);
btree_init_mempool32(&super->s_shadow_tree.segment_map,
super->s_btree_pool);
ret = logfs_init_mapping(sb);
if (ret)
return ret;
ret = __logfs_read_sb(sb);
if (ret)
return ret;
if (super->s_feature_incompat & ~LOGFS_FEATURES_INCOMPAT)
return -EIO;
if ((super->s_feature_ro_compat & ~LOGFS_FEATURES_RO_COMPAT) &&
!read_only)
return -EIO;
ret = logfs_init_rw(sb);
if (ret)
return ret;
ret = logfs_init_areas(sb);
if (ret)
return ret;
ret = logfs_init_gc(sb);
if (ret)
return ret;
ret = logfs_init_journal(sb);
if (ret)
return ret;
return 0;
}
static void logfs_kill_sb(struct super_block *sb)
{
struct logfs_super *super = logfs_super(sb);
log_super("LogFS: Start unmounting\n");
/* Alias entries slow down mount, so evict as many as possible */
sync_filesystem(sb);
logfs_write_anchor(sb);
free_areas(sb);
/*
* From this point on alias entries are simply dropped - and any
* writes to the object store are considered bugs.
*/
log_super("LogFS: Now in shutdown\n");
generic_shutdown_super(sb);
super->s_flags |= LOGFS_SB_FLAG_SHUTDOWN;
BUG_ON(super->s_dirty_used_bytes || super->s_dirty_free_bytes);
logfs_cleanup_gc(sb);
logfs_cleanup_journal(sb);
logfs_cleanup_areas(sb);
logfs_cleanup_rw(sb);
if (super->s_erase_page)
__free_page(super->s_erase_page);
super->s_devops->put_device(super);
logfs_mempool_destroy(super->s_btree_pool);
logfs_mempool_destroy(super->s_alias_pool);
kfree(super);
log_super("LogFS: Finished unmounting\n");
}
static struct dentry *logfs_get_sb_device(struct logfs_super *super,
struct file_system_type *type, int flags)
{
struct super_block *sb;
int err = -ENOMEM;
static int mount_count;
log_super("LogFS: Start mount %x\n", mount_count++);
err = -EINVAL;
sb = sget(type, logfs_sb_test, logfs_sb_set, flags | MS_NOATIME, super);
if (IS_ERR(sb)) {
super->s_devops->put_device(super);
kfree(super);
return ERR_CAST(sb);
}
if (sb->s_root) {
/* Device is already in use */
super->s_devops->put_device(super);
kfree(super);
return dget(sb->s_root);
}
/*
* sb->s_maxbytes is limited to 8TB. On 32bit systems, the page cache
* only covers 16TB and the upper 8TB are used for indirect blocks.
* On 64bit system we could bump up the limit, but that would make
* the filesystem incompatible with 32bit systems.
*/
sb->s_maxbytes = (1ull << 43) - 1;
sb->s_max_links = LOGFS_LINK_MAX;
sb->s_op = &logfs_super_operations;
err = logfs_read_sb(sb, sb->s_flags & MS_RDONLY);
if (err)
goto err1;
sb->s_flags |= MS_ACTIVE;
err = logfs_get_sb_final(sb);
if (err) {
deactivate_locked_super(sb);
return ERR_PTR(err);
}
return dget(sb->s_root);
err1:
/* no ->s_root, no ->put_super() */
iput(super->s_master_inode);
iput(super->s_segfile_inode);
iput(super->s_mapping_inode);
deactivate_locked_super(sb);
return ERR_PTR(err);
}
static struct dentry *logfs_mount(struct file_system_type *type, int flags,
const char *devname, void *data)
{
ulong mtdnr;
struct logfs_super *super;
int err;
super = kzalloc(sizeof(*super), GFP_KERNEL);
if (!super)
return ERR_PTR(-ENOMEM);
mutex_init(&super->s_dirop_mutex);
mutex_init(&super->s_object_alias_mutex);
INIT_LIST_HEAD(&super->s_freeing_list);
if (!devname)
err = logfs_get_sb_bdev(super, type, devname);
else if (strncmp(devname, "mtd", 3))
err = logfs_get_sb_bdev(super, type, devname);
else {
char *garbage;
mtdnr = simple_strtoul(devname+3, &garbage, 0);
if (*garbage)
err = -EINVAL;
else
err = logfs_get_sb_mtd(super, mtdnr);
}
if (err) {
kfree(super);
return ERR_PTR(err);
}
return logfs_get_sb_device(super, type, flags);
}
static struct file_system_type logfs_fs_type = {
.owner = THIS_MODULE,
.name = "logfs",
.mount = logfs_mount,
.kill_sb = logfs_kill_sb,
.fs_flags = FS_REQUIRES_DEV,
};
MODULE_ALIAS_FS("logfs");
static int __init logfs_init(void)
{
int ret;
emergency_page = alloc_pages(GFP_KERNEL, 0);
if (!emergency_page)
return -ENOMEM;
ret = logfs_compr_init();
if (ret)
goto out1;
ret = logfs_init_inode_cache();
if (ret)
goto out2;
ret = register_filesystem(&logfs_fs_type);
if (!ret)
return 0;
logfs_destroy_inode_cache();
out2:
logfs_compr_exit();
out1:
__free_pages(emergency_page, 0);
return ret;
}
static void __exit logfs_exit(void)
{
unregister_filesystem(&logfs_fs_type);
logfs_destroy_inode_cache();
logfs_compr_exit();
__free_pages(emergency_page, 0);
}
module_init(logfs_init);
module_exit(logfs_exit);
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Joern Engel <joern@logfs.org>");
MODULE_DESCRIPTION("scalable flash filesystem");
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