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-rw-r--r--fs/logfs/journal.c894
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);
-}