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-rw-r--r--fs/logfs/super.c653
1 files changed, 0 insertions, 653 deletions
diff --git a/fs/logfs/super.c b/fs/logfs/super.c
deleted file mode 100644
index 5751082dba52..000000000000
--- a/fs/logfs/super.c
+++ /dev/null
@@ -1,653 +0,0 @@
-/*
- * 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
- put_page(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);
- put_page(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)) {
- put_page(first);
- return NULL;
- }
-
- if (!logfs_check_ds(page_address(first))) {
- put_page(last);
- return first;
- }
-
- /* First one didn't work, try the second superblock */
- if (!logfs_check_ds(page_address(last))) {
- put_page(first);
- return last;
- }
-
- /* Neither worked, sorry folks */
- put_page(first);
- put_page(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;
- put_page(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");