diff options
Diffstat (limited to 'fs/logfs/journal.c')
| -rw-r--r-- | fs/logfs/journal.c | 894 |
1 files changed, 0 insertions, 894 deletions
diff --git a/fs/logfs/journal.c b/fs/logfs/journal.c deleted file mode 100644 index 2a09b8d73989..000000000000 --- a/fs/logfs/journal.c +++ /dev/null @@ -1,894 +0,0 @@ -/* - * fs/logfs/journal.c - journal handling code - * - * As should be obvious for Linux kernel code, license is GPLv2 - * - * Copyright (c) 2005-2008 Joern Engel <joern@logfs.org> - */ -#include "logfs.h" -#include <linux/slab.h> - -static void logfs_calc_free(struct super_block *sb) -{ - struct logfs_super *super = logfs_super(sb); - u64 reserve, no_segs = super->s_no_segs; - s64 free; - int i; - - /* superblock segments */ - no_segs -= 2; - super->s_no_journal_segs = 0; - /* journal */ - journal_for_each(i) - if (super->s_journal_seg[i]) { - no_segs--; - super->s_no_journal_segs++; - } - - /* open segments plus one extra per level for GC */ - no_segs -= 2 * super->s_total_levels; - - free = no_segs * (super->s_segsize - LOGFS_SEGMENT_RESERVE); - free -= super->s_used_bytes; - /* just a bit extra */ - free -= super->s_total_levels * 4096; - - /* Bad blocks are 'paid' for with speed reserve - the filesystem - * simply gets slower as bad blocks accumulate. Until the bad blocks - * exceed the speed reserve - then the filesystem gets smaller. - */ - reserve = super->s_bad_segments + super->s_bad_seg_reserve; - reserve *= super->s_segsize - LOGFS_SEGMENT_RESERVE; - reserve = max(reserve, super->s_speed_reserve); - free -= reserve; - if (free < 0) - free = 0; - - super->s_free_bytes = free; -} - -static void reserve_sb_and_journal(struct super_block *sb) -{ - struct logfs_super *super = logfs_super(sb); - struct btree_head32 *head = &super->s_reserved_segments; - int i, err; - - err = btree_insert32(head, seg_no(sb, super->s_sb_ofs[0]), (void *)1, - GFP_KERNEL); - BUG_ON(err); - - err = btree_insert32(head, seg_no(sb, super->s_sb_ofs[1]), (void *)1, - GFP_KERNEL); - BUG_ON(err); - - journal_for_each(i) { - if (!super->s_journal_seg[i]) - continue; - err = btree_insert32(head, super->s_journal_seg[i], (void *)1, - GFP_KERNEL); - BUG_ON(err); - } -} - -static void read_dynsb(struct super_block *sb, - struct logfs_je_dynsb *dynsb) -{ - struct logfs_super *super = logfs_super(sb); - - super->s_gec = be64_to_cpu(dynsb->ds_gec); - super->s_sweeper = be64_to_cpu(dynsb->ds_sweeper); - super->s_victim_ino = be64_to_cpu(dynsb->ds_victim_ino); - super->s_rename_dir = be64_to_cpu(dynsb->ds_rename_dir); - super->s_rename_pos = be64_to_cpu(dynsb->ds_rename_pos); - super->s_used_bytes = be64_to_cpu(dynsb->ds_used_bytes); - super->s_generation = be32_to_cpu(dynsb->ds_generation); -} - -static void read_anchor(struct super_block *sb, - struct logfs_je_anchor *da) -{ - struct logfs_super *super = logfs_super(sb); - struct inode *inode = super->s_master_inode; - struct logfs_inode *li = logfs_inode(inode); - int i; - - super->s_last_ino = be64_to_cpu(da->da_last_ino); - li->li_flags = 0; - li->li_height = da->da_height; - i_size_write(inode, be64_to_cpu(da->da_size)); - li->li_used_bytes = be64_to_cpu(da->da_used_bytes); - - for (i = 0; i < LOGFS_EMBEDDED_FIELDS; i++) - li->li_data[i] = be64_to_cpu(da->da_data[i]); -} - -static void read_erasecount(struct super_block *sb, - struct logfs_je_journal_ec *ec) -{ - struct logfs_super *super = logfs_super(sb); - int i; - - journal_for_each(i) - super->s_journal_ec[i] = be32_to_cpu(ec->ec[i]); -} - -static int read_area(struct super_block *sb, struct logfs_je_area *a) -{ - struct logfs_super *super = logfs_super(sb); - struct logfs_area *area = super->s_area[a->gc_level]; - u64 ofs; - u32 writemask = ~(super->s_writesize - 1); - - if (a->gc_level >= LOGFS_NO_AREAS) - return -EIO; - if (a->vim != VIM_DEFAULT) - return -EIO; /* TODO: close area and continue */ - - area->a_used_bytes = be32_to_cpu(a->used_bytes); - area->a_written_bytes = area->a_used_bytes & writemask; - area->a_segno = be32_to_cpu(a->segno); - if (area->a_segno) - area->a_is_open = 1; - - ofs = dev_ofs(sb, area->a_segno, area->a_written_bytes); - if (super->s_writesize > 1) - return logfs_buf_recover(area, ofs, a + 1, super->s_writesize); - else - return logfs_buf_recover(area, ofs, NULL, 0); -} - -static void *unpack(void *from, void *to) -{ - struct logfs_journal_header *jh = from; - void *data = from + sizeof(struct logfs_journal_header); - int err; - size_t inlen, outlen; - - inlen = be16_to_cpu(jh->h_len); - outlen = be16_to_cpu(jh->h_datalen); - - if (jh->h_compr == COMPR_NONE) - memcpy(to, data, inlen); - else { - err = logfs_uncompress(data, to, inlen, outlen); - BUG_ON(err); - } - return to; -} - -static int __read_je_header(struct super_block *sb, u64 ofs, - struct logfs_journal_header *jh) -{ - struct logfs_super *super = logfs_super(sb); - size_t bufsize = max_t(size_t, sb->s_blocksize, super->s_writesize) - + MAX_JOURNAL_HEADER; - u16 type, len, datalen; - int err; - - /* read header only */ - err = wbuf_read(sb, ofs, sizeof(*jh), jh); - if (err) - return err; - type = be16_to_cpu(jh->h_type); - len = be16_to_cpu(jh->h_len); - datalen = be16_to_cpu(jh->h_datalen); - if (len > sb->s_blocksize) - return -EIO; - if ((type < JE_FIRST) || (type > JE_LAST)) - return -EIO; - if (datalen > bufsize) - return -EIO; - return 0; -} - -static int __read_je_payload(struct super_block *sb, u64 ofs, - struct logfs_journal_header *jh) -{ - u16 len; - int err; - - len = be16_to_cpu(jh->h_len); - err = wbuf_read(sb, ofs + sizeof(*jh), len, jh + 1); - if (err) - return err; - if (jh->h_crc != logfs_crc32(jh, len + sizeof(*jh), 4)) { - /* Old code was confused. It forgot about the header length - * and stopped calculating the crc 16 bytes before the end - * of data - ick! - * FIXME: Remove this hack once the old code is fixed. - */ - if (jh->h_crc == logfs_crc32(jh, len, 4)) - WARN_ON_ONCE(1); - else - return -EIO; - } - return 0; -} - -/* - * jh needs to be large enough to hold the complete entry, not just the header - */ -static int __read_je(struct super_block *sb, u64 ofs, - struct logfs_journal_header *jh) -{ - int err; - - err = __read_je_header(sb, ofs, jh); - if (err) - return err; - return __read_je_payload(sb, ofs, jh); -} - -static int read_je(struct super_block *sb, u64 ofs) -{ - struct logfs_super *super = logfs_super(sb); - struct logfs_journal_header *jh = super->s_compressed_je; - void *scratch = super->s_je; - u16 type, datalen; - int err; - - err = __read_je(sb, ofs, jh); - if (err) - return err; - type = be16_to_cpu(jh->h_type); - datalen = be16_to_cpu(jh->h_datalen); - - switch (type) { - case JE_DYNSB: - read_dynsb(sb, unpack(jh, scratch)); - break; - case JE_ANCHOR: - read_anchor(sb, unpack(jh, scratch)); - break; - case JE_ERASECOUNT: - read_erasecount(sb, unpack(jh, scratch)); - break; - case JE_AREA: - err = read_area(sb, unpack(jh, scratch)); - break; - case JE_OBJ_ALIAS: - err = logfs_load_object_aliases(sb, unpack(jh, scratch), - datalen); - break; - default: - WARN_ON_ONCE(1); - return -EIO; - } - return err; -} - -static int logfs_read_segment(struct super_block *sb, u32 segno) -{ - struct logfs_super *super = logfs_super(sb); - struct logfs_journal_header *jh = super->s_compressed_je; - u64 ofs, seg_ofs = dev_ofs(sb, segno, 0); - u32 h_ofs, last_ofs = 0; - u16 len, datalen, last_len = 0; - int i, err; - - /* search for most recent commit */ - for (h_ofs = 0; h_ofs < super->s_segsize; h_ofs += sizeof(*jh)) { - ofs = seg_ofs + h_ofs; - err = __read_je_header(sb, ofs, jh); - if (err) - continue; - if (jh->h_type != cpu_to_be16(JE_COMMIT)) - continue; - err = __read_je_payload(sb, ofs, jh); - if (err) - continue; - len = be16_to_cpu(jh->h_len); - datalen = be16_to_cpu(jh->h_datalen); - if ((datalen > sizeof(super->s_je_array)) || - (datalen % sizeof(__be64))) - continue; - last_ofs = h_ofs; - last_len = datalen; - h_ofs += ALIGN(len, sizeof(*jh)) - sizeof(*jh); - } - /* read commit */ - if (last_ofs == 0) - return -ENOENT; - ofs = seg_ofs + last_ofs; - log_journal("Read commit from %llx\n", ofs); - err = __read_je(sb, ofs, jh); - BUG_ON(err); /* We should have caught it in the scan loop already */ - if (err) - return err; - /* uncompress */ - unpack(jh, super->s_je_array); - super->s_no_je = last_len / sizeof(__be64); - /* iterate over array */ - for (i = 0; i < super->s_no_je; i++) { - err = read_je(sb, be64_to_cpu(super->s_je_array[i])); - if (err) - return err; - } - super->s_journal_area->a_segno = segno; - return 0; -} - -static u64 read_gec(struct super_block *sb, u32 segno) -{ - struct logfs_segment_header sh; - __be32 crc; - int err; - - if (!segno) - return 0; - err = wbuf_read(sb, dev_ofs(sb, segno, 0), sizeof(sh), &sh); - if (err) - return 0; - crc = logfs_crc32(&sh, sizeof(sh), 4); - if (crc != sh.crc) { - WARN_ON(sh.gec != cpu_to_be64(0xffffffffffffffffull)); - /* Most likely it was just erased */ - return 0; - } - return be64_to_cpu(sh.gec); -} - -static int logfs_read_journal(struct super_block *sb) -{ - struct logfs_super *super = logfs_super(sb); - u64 gec[LOGFS_JOURNAL_SEGS], max; - u32 segno; - int i, max_i; - - max = 0; - max_i = -1; - journal_for_each(i) { - segno = super->s_journal_seg[i]; - gec[i] = read_gec(sb, super->s_journal_seg[i]); - if (gec[i] > max) { - max = gec[i]; - max_i = i; - } - } - if (max_i == -1) - return -EIO; - /* FIXME: Try older segments in case of error */ - return logfs_read_segment(sb, super->s_journal_seg[max_i]); -} - -/* - * First search the current segment (outer loop), then pick the next segment - * in the array, skipping any zero entries (inner loop). - */ -static void journal_get_free_segment(struct logfs_area *area) -{ - struct logfs_super *super = logfs_super(area->a_sb); - int i; - - journal_for_each(i) { - if (area->a_segno != super->s_journal_seg[i]) - continue; - - do { - i++; - if (i == LOGFS_JOURNAL_SEGS) - i = 0; - } while (!super->s_journal_seg[i]); - - area->a_segno = super->s_journal_seg[i]; - area->a_erase_count = ++(super->s_journal_ec[i]); - log_journal("Journal now at %x (ec %x)\n", area->a_segno, - area->a_erase_count); - return; - } - BUG(); -} - -static void journal_get_erase_count(struct logfs_area *area) -{ - /* erase count is stored globally and incremented in - * journal_get_free_segment() - nothing to do here */ -} - -static int journal_erase_segment(struct logfs_area *area) -{ - struct super_block *sb = area->a_sb; - union { - struct logfs_segment_header sh; - unsigned char c[ALIGN(sizeof(struct logfs_segment_header), 16)]; - } u; - u64 ofs; - int err; - - err = logfs_erase_segment(sb, area->a_segno, 1); - if (err) - return err; - - memset(&u, 0, sizeof(u)); - u.sh.pad = 0; - u.sh.type = SEG_JOURNAL; - u.sh.level = 0; - u.sh.segno = cpu_to_be32(area->a_segno); - u.sh.ec = cpu_to_be32(area->a_erase_count); - u.sh.gec = cpu_to_be64(logfs_super(sb)->s_gec); - u.sh.crc = logfs_crc32(&u.sh, sizeof(u.sh), 4); - - /* This causes a bug in segment.c. Not yet. */ - //logfs_set_segment_erased(sb, area->a_segno, area->a_erase_count, 0); - - ofs = dev_ofs(sb, area->a_segno, 0); - area->a_used_bytes = sizeof(u); - logfs_buf_write(area, ofs, &u, sizeof(u)); - return 0; -} - -static size_t __logfs_write_header(struct logfs_super *super, - struct logfs_journal_header *jh, size_t len, size_t datalen, - u16 type, u8 compr) -{ - jh->h_len = cpu_to_be16(len); - jh->h_type = cpu_to_be16(type); - jh->h_datalen = cpu_to_be16(datalen); - jh->h_compr = compr; - jh->h_pad[0] = 'H'; - jh->h_pad[1] = 'E'; - jh->h_pad[2] = 'A'; - jh->h_pad[3] = 'D'; - jh->h_pad[4] = 'R'; - jh->h_crc = logfs_crc32(jh, len + sizeof(*jh), 4); - return ALIGN(len, 16) + sizeof(*jh); -} - -static size_t logfs_write_header(struct logfs_super *super, - struct logfs_journal_header *jh, size_t datalen, u16 type) -{ - size_t len = datalen; - - return __logfs_write_header(super, jh, len, datalen, type, COMPR_NONE); -} - -static inline size_t logfs_journal_erasecount_size(struct logfs_super *super) -{ - return LOGFS_JOURNAL_SEGS * sizeof(__be32); -} - -static void *logfs_write_erasecount(struct super_block *sb, void *_ec, - u16 *type, size_t *len) -{ - struct logfs_super *super = logfs_super(sb); - struct logfs_je_journal_ec *ec = _ec; - int i; - - journal_for_each(i) - ec->ec[i] = cpu_to_be32(super->s_journal_ec[i]); - *type = JE_ERASECOUNT; - *len = logfs_journal_erasecount_size(super); - return ec; -} - -static void account_shadow(void *_shadow, unsigned long _sb, u64 ignore, - size_t ignore2) -{ - struct logfs_shadow *shadow = _shadow; - struct super_block *sb = (void *)_sb; - struct logfs_super *super = logfs_super(sb); - - /* consume new space */ - super->s_free_bytes -= shadow->new_len; - super->s_used_bytes += shadow->new_len; - super->s_dirty_used_bytes -= shadow->new_len; - - /* free up old space */ - super->s_free_bytes += shadow->old_len; - super->s_used_bytes -= shadow->old_len; - super->s_dirty_free_bytes -= shadow->old_len; - - logfs_set_segment_used(sb, shadow->old_ofs, -shadow->old_len); - logfs_set_segment_used(sb, shadow->new_ofs, shadow->new_len); - - log_journal("account_shadow(%llx, %llx, %x) %llx->%llx %x->%x\n", - shadow->ino, shadow->bix, shadow->gc_level, - shadow->old_ofs, shadow->new_ofs, - shadow->old_len, shadow->new_len); - mempool_free(shadow, super->s_shadow_pool); -} - -static void account_shadows(struct super_block *sb) -{ - struct logfs_super *super = logfs_super(sb); - struct inode *inode = super->s_master_inode; - struct logfs_inode *li = logfs_inode(inode); - struct shadow_tree *tree = &super->s_shadow_tree; - - btree_grim_visitor64(&tree->new, (unsigned long)sb, account_shadow); - btree_grim_visitor64(&tree->old, (unsigned long)sb, account_shadow); - btree_grim_visitor32(&tree->segment_map, 0, NULL); - tree->no_shadowed_segments = 0; - - if (li->li_block) { - /* - * We never actually use the structure, when attached to the - * master inode. But it is easier to always free it here than - * to have checks in several places elsewhere when allocating - * it. - */ - li->li_block->ops->free_block(sb, li->li_block); - } - BUG_ON((s64)li->li_used_bytes < 0); -} - -static void *__logfs_write_anchor(struct super_block *sb, void *_da, - u16 *type, size_t *len) -{ - struct logfs_super *super = logfs_super(sb); - struct logfs_je_anchor *da = _da; - struct inode *inode = super->s_master_inode; - struct logfs_inode *li = logfs_inode(inode); - int i; - - da->da_height = li->li_height; - da->da_last_ino = cpu_to_be64(super->s_last_ino); - da->da_size = cpu_to_be64(i_size_read(inode)); - da->da_used_bytes = cpu_to_be64(li->li_used_bytes); - for (i = 0; i < LOGFS_EMBEDDED_FIELDS; i++) - da->da_data[i] = cpu_to_be64(li->li_data[i]); - *type = JE_ANCHOR; - *len = sizeof(*da); - return da; -} - -static void *logfs_write_dynsb(struct super_block *sb, void *_dynsb, - u16 *type, size_t *len) -{ - struct logfs_super *super = logfs_super(sb); - struct logfs_je_dynsb *dynsb = _dynsb; - - dynsb->ds_gec = cpu_to_be64(super->s_gec); - dynsb->ds_sweeper = cpu_to_be64(super->s_sweeper); - dynsb->ds_victim_ino = cpu_to_be64(super->s_victim_ino); - dynsb->ds_rename_dir = cpu_to_be64(super->s_rename_dir); - dynsb->ds_rename_pos = cpu_to_be64(super->s_rename_pos); - dynsb->ds_used_bytes = cpu_to_be64(super->s_used_bytes); - dynsb->ds_generation = cpu_to_be32(super->s_generation); - *type = JE_DYNSB; - *len = sizeof(*dynsb); - return dynsb; -} - -static void write_wbuf(struct super_block *sb, struct logfs_area *area, - void *wbuf) -{ - struct logfs_super *super = logfs_super(sb); - struct address_space *mapping = super->s_mapping_inode->i_mapping; - u64 ofs; - pgoff_t index; - int page_ofs; - struct page *page; - - ofs = dev_ofs(sb, area->a_segno, - area->a_used_bytes & ~(super->s_writesize - 1)); - index = ofs >> PAGE_SHIFT; - page_ofs = ofs & (PAGE_SIZE - 1); - - page = find_or_create_page(mapping, index, GFP_NOFS); - BUG_ON(!page); - memcpy(wbuf, page_address(page) + page_ofs, super->s_writesize); - unlock_page(page); -} - -static void *logfs_write_area(struct super_block *sb, void *_a, - u16 *type, size_t *len) -{ - struct logfs_super *super = logfs_super(sb); - struct logfs_area *area = super->s_area[super->s_sum_index]; - struct logfs_je_area *a = _a; - - a->vim = VIM_DEFAULT; - a->gc_level = super->s_sum_index; - a->used_bytes = cpu_to_be32(area->a_used_bytes); - a->segno = cpu_to_be32(area->a_segno); - if (super->s_writesize > 1) - write_wbuf(sb, area, a + 1); - - *type = JE_AREA; - *len = sizeof(*a) + super->s_writesize; - return a; -} - -static void *logfs_write_commit(struct super_block *sb, void *h, - u16 *type, size_t *len) -{ - struct logfs_super *super = logfs_super(sb); - - *type = JE_COMMIT; - *len = super->s_no_je * sizeof(__be64); - return super->s_je_array; -} - -static size_t __logfs_write_je(struct super_block *sb, void *buf, u16 type, - size_t len) -{ - struct logfs_super *super = logfs_super(sb); - void *header = super->s_compressed_je; - void *data = header + sizeof(struct logfs_journal_header); - ssize_t compr_len, pad_len; - u8 compr = COMPR_ZLIB; - - if (len == 0) - return logfs_write_header(super, header, 0, type); - - compr_len = logfs_compress(buf, data, len, sb->s_blocksize); - if (compr_len < 0 || type == JE_ANCHOR) { - memcpy(data, buf, len); - compr_len = len; - compr = COMPR_NONE; - } - - pad_len = ALIGN(compr_len, 16); - memset(data + compr_len, 0, pad_len - compr_len); - - return __logfs_write_header(super, header, compr_len, len, type, compr); -} - -static s64 logfs_get_free_bytes(struct logfs_area *area, size_t *bytes, - int must_pad) -{ - u32 writesize = logfs_super(area->a_sb)->s_writesize; - s32 ofs; - int ret; - - ret = logfs_open_area(area, *bytes); - if (ret) - return -EAGAIN; - - ofs = area->a_used_bytes; - area->a_used_bytes += *bytes; - - if (must_pad) { - area->a_used_bytes = ALIGN(area->a_used_bytes, writesize); - *bytes = area->a_used_bytes - ofs; - } - - return dev_ofs(area->a_sb, area->a_segno, ofs); -} - -static int logfs_write_je_buf(struct super_block *sb, void *buf, u16 type, - size_t buf_len) -{ - struct logfs_super *super = logfs_super(sb); - struct logfs_area *area = super->s_journal_area; - struct logfs_journal_header *jh = super->s_compressed_je; - size_t len; - int must_pad = 0; - s64 ofs; - - len = __logfs_write_je(sb, buf, type, buf_len); - if (jh->h_type == cpu_to_be16(JE_COMMIT)) - must_pad = 1; - - ofs = logfs_get_free_bytes(area, &len, must_pad); - if (ofs < 0) - return ofs; - logfs_buf_write(area, ofs, super->s_compressed_je, len); - BUG_ON(super->s_no_je >= MAX_JOURNAL_ENTRIES); - super->s_je_array[super->s_no_je++] = cpu_to_be64(ofs); - return 0; -} - -static int logfs_write_je(struct super_block *sb, - void* (*write)(struct super_block *sb, void *scratch, - u16 *type, size_t *len)) -{ - void *buf; - size_t len; - u16 type; - - buf = write(sb, logfs_super(sb)->s_je, &type, &len); - return logfs_write_je_buf(sb, buf, type, len); -} - -int write_alias_journal(struct super_block *sb, u64 ino, u64 bix, - level_t level, int child_no, __be64 val) -{ - struct logfs_super *super = logfs_super(sb); - struct logfs_obj_alias *oa = super->s_je; - int err = 0, fill = super->s_je_fill; - - log_aliases("logfs_write_obj_aliases #%x(%llx, %llx, %x, %x) %llx\n", - fill, ino, bix, level, child_no, be64_to_cpu(val)); - oa[fill].ino = cpu_to_be64(ino); - oa[fill].bix = cpu_to_be64(bix); - oa[fill].val = val; - oa[fill].level = (__force u8)level; - oa[fill].child_no = cpu_to_be16(child_no); - fill++; - if (fill >= sb->s_blocksize / sizeof(*oa)) { - err = logfs_write_je_buf(sb, oa, JE_OBJ_ALIAS, sb->s_blocksize); - fill = 0; - } - - super->s_je_fill = fill; - return err; -} - -static int logfs_write_obj_aliases(struct super_block *sb) -{ - struct logfs_super *super = logfs_super(sb); - int err; - - log_journal("logfs_write_obj_aliases: %d aliases to write\n", - super->s_no_object_aliases); - super->s_je_fill = 0; - err = logfs_write_obj_aliases_pagecache(sb); - if (err) - return err; - - if (super->s_je_fill) - err = logfs_write_je_buf(sb, super->s_je, JE_OBJ_ALIAS, - super->s_je_fill - * sizeof(struct logfs_obj_alias)); - return err; -} - -/* - * Write all journal entries. The goto logic ensures that all journal entries - * are written whenever a new segment is used. It is ugly and potentially a - * bit wasteful, but robustness is more important. With this we can *always* - * erase all journal segments except the one containing the most recent commit. - */ -void logfs_write_anchor(struct super_block *sb) -{ - struct logfs_super *super = logfs_super(sb); - struct logfs_area *area = super->s_journal_area; - int i, err; - - if (!(super->s_flags & LOGFS_SB_FLAG_DIRTY)) - return; - super->s_flags &= ~LOGFS_SB_FLAG_DIRTY; - - BUG_ON(super->s_flags & LOGFS_SB_FLAG_SHUTDOWN); - mutex_lock(&super->s_journal_mutex); - - /* Do this first or suffer corruption */ - logfs_sync_segments(sb); - account_shadows(sb); - -again: - super->s_no_je = 0; - for_each_area(i) { - if (!super->s_area[i]->a_is_open) - continue; - super->s_sum_index = i; - err = logfs_write_je(sb, logfs_write_area); - if (err) - goto again; - } - err = logfs_write_obj_aliases(sb); - if (err) - goto again; - err = logfs_write_je(sb, logfs_write_erasecount); - if (err) - goto again; - err = logfs_write_je(sb, __logfs_write_anchor); - if (err) - goto again; - err = logfs_write_je(sb, logfs_write_dynsb); - if (err) - goto again; - /* - * Order is imperative. First we sync all writes, including the - * non-committed journal writes. Then we write the final commit and - * sync the current journal segment. - * There is a theoretical bug here. Syncing the journal segment will - * write a number of journal entries and the final commit. All these - * are written in a single operation. If the device layer writes the - * data back-to-front, the commit will precede the other journal - * entries, leaving a race window. - * Two fixes are possible. Preferred is to fix the device layer to - * ensure writes happen front-to-back. Alternatively we can insert - * another logfs_sync_area() super->s_devops->sync() combo before - * writing the commit. - */ - /* - * On another subject, super->s_devops->sync is usually not necessary. - * Unless called from sys_sync or friends, a barrier would suffice. - */ - super->s_devops->sync(sb); - err = logfs_write_je(sb, logfs_write_commit); - if (err) - goto again; - log_journal("Write commit to %llx\n", - be64_to_cpu(super->s_je_array[super->s_no_je - 1])); - logfs_sync_area(area); - BUG_ON(area->a_used_bytes != area->a_written_bytes); - super->s_devops->sync(sb); - - mutex_unlock(&super->s_journal_mutex); - return; -} - -void do_logfs_journal_wl_pass(struct super_block *sb) -{ - struct logfs_super *super = logfs_super(sb); - struct logfs_area *area = super->s_journal_area; - struct btree_head32 *head = &super->s_reserved_segments; - u32 segno, ec; - int i, err; - - log_journal("Journal requires wear-leveling.\n"); - /* Drop old segments */ - journal_for_each(i) - if (super->s_journal_seg[i]) { - btree_remove32(head, super->s_journal_seg[i]); - logfs_set_segment_unreserved(sb, - super->s_journal_seg[i], - super->s_journal_ec[i]); - super->s_journal_seg[i] = 0; - super->s_journal_ec[i] = 0; - } - /* Get new segments */ - for (i = 0; i < super->s_no_journal_segs; i++) { - segno = get_best_cand(sb, &super->s_reserve_list, &ec); - super->s_journal_seg[i] = segno; - super->s_journal_ec[i] = ec; - logfs_set_segment_reserved(sb, segno); - err = btree_insert32(head, segno, (void *)1, GFP_NOFS); - BUG_ON(err); /* mempool should prevent this */ - err = logfs_erase_segment(sb, segno, 1); - BUG_ON(err); /* FIXME: remount-ro would be nicer */ - } - /* Manually move journal_area */ - freeseg(sb, area->a_segno); - area->a_segno = super->s_journal_seg[0]; - area->a_is_open = 0; - area->a_used_bytes = 0; - /* Write journal */ - logfs_write_anchor(sb); - /* Write superblocks */ - err = logfs_write_sb(sb); - BUG_ON(err); -} - -static const struct logfs_area_ops journal_area_ops = { - .get_free_segment = journal_get_free_segment, - .get_erase_count = journal_get_erase_count, - .erase_segment = journal_erase_segment, -}; - -int logfs_init_journal(struct super_block *sb) -{ - struct logfs_super *super = logfs_super(sb); - size_t bufsize = max_t(size_t, sb->s_blocksize, super->s_writesize) - + MAX_JOURNAL_HEADER; - int ret = -ENOMEM; - - mutex_init(&super->s_journal_mutex); - btree_init_mempool32(&super->s_reserved_segments, super->s_btree_pool); - - super->s_je = kzalloc(bufsize, GFP_KERNEL); - if (!super->s_je) - return ret; - - super->s_compressed_je = kzalloc(bufsize, GFP_KERNEL); - if (!super->s_compressed_je) - return ret; - - super->s_master_inode = logfs_new_meta_inode(sb, LOGFS_INO_MASTER); - if (IS_ERR(super->s_master_inode)) - return PTR_ERR(super->s_master_inode); - - ret = logfs_read_journal(sb); - if (ret) - return -EIO; - - reserve_sb_and_journal(sb); - logfs_calc_free(sb); - - super->s_journal_area->a_ops = &journal_area_ops; - return 0; -} - -void logfs_cleanup_journal(struct super_block *sb) -{ - struct logfs_super *super = logfs_super(sb); - - btree_grim_visitor32(&super->s_reserved_segments, 0, NULL); - - kfree(super->s_compressed_je); - kfree(super->s_je); -} |