diff options
Diffstat (limited to 'fs/gfs2/log.c')
| -rw-r--r-- | fs/gfs2/log.c | 687 |
1 files changed, 687 insertions, 0 deletions
diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c new file mode 100644 index 00000000000..554fe5bd1b7 --- /dev/null +++ b/fs/gfs2/log.c @@ -0,0 +1,687 @@ +/* + * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. + * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved. + * + * This copyrighted material is made available to anyone wishing to use, + * modify, copy, or redistribute it subject to the terms and conditions + * of the GNU General Public License version 2. + */ + +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/completion.h> +#include <linux/buffer_head.h> +#include <linux/gfs2_ondisk.h> +#include <linux/crc32.h> +#include <linux/lm_interface.h> + +#include "gfs2.h" +#include "incore.h" +#include "bmap.h" +#include "glock.h" +#include "log.h" +#include "lops.h" +#include "meta_io.h" +#include "util.h" +#include "dir.h" + +#define PULL 1 + +/** + * gfs2_struct2blk - compute stuff + * @sdp: the filesystem + * @nstruct: the number of structures + * @ssize: the size of the structures + * + * Compute the number of log descriptor blocks needed to hold a certain number + * of structures of a certain size. + * + * Returns: the number of blocks needed (minimum is always 1) + */ + +unsigned int gfs2_struct2blk(struct gfs2_sbd *sdp, unsigned int nstruct, + unsigned int ssize) +{ + unsigned int blks; + unsigned int first, second; + + blks = 1; + first = (sdp->sd_sb.sb_bsize - sizeof(struct gfs2_log_descriptor)) / ssize; + + if (nstruct > first) { + second = (sdp->sd_sb.sb_bsize - + sizeof(struct gfs2_meta_header)) / ssize; + blks += DIV_ROUND_UP(nstruct - first, second); + } + + return blks; +} + +/** + * gfs2_ail1_start_one - Start I/O on a part of the AIL + * @sdp: the filesystem + * @tr: the part of the AIL + * + */ + +static void gfs2_ail1_start_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai) +{ + struct gfs2_bufdata *bd, *s; + struct buffer_head *bh; + int retry; + + BUG_ON(!spin_is_locked(&sdp->sd_log_lock)); + + do { + retry = 0; + + list_for_each_entry_safe_reverse(bd, s, &ai->ai_ail1_list, + bd_ail_st_list) { + bh = bd->bd_bh; + + gfs2_assert(sdp, bd->bd_ail == ai); + + if (!buffer_busy(bh)) { + if (!buffer_uptodate(bh)) { + gfs2_log_unlock(sdp); + gfs2_io_error_bh(sdp, bh); + gfs2_log_lock(sdp); + } + list_move(&bd->bd_ail_st_list, &ai->ai_ail2_list); + continue; + } + + if (!buffer_dirty(bh)) + continue; + + list_move(&bd->bd_ail_st_list, &ai->ai_ail1_list); + + gfs2_log_unlock(sdp); + wait_on_buffer(bh); + ll_rw_block(WRITE, 1, &bh); + gfs2_log_lock(sdp); + + retry = 1; + break; + } + } while (retry); +} + +/** + * gfs2_ail1_empty_one - Check whether or not a trans in the AIL has been synced + * @sdp: the filesystem + * @ai: the AIL entry + * + */ + +static int gfs2_ail1_empty_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai, int flags) +{ + struct gfs2_bufdata *bd, *s; + struct buffer_head *bh; + + list_for_each_entry_safe_reverse(bd, s, &ai->ai_ail1_list, + bd_ail_st_list) { + bh = bd->bd_bh; + + gfs2_assert(sdp, bd->bd_ail == ai); + + if (buffer_busy(bh)) { + if (flags & DIO_ALL) + continue; + else + break; + } + + if (!buffer_uptodate(bh)) + gfs2_io_error_bh(sdp, bh); + + list_move(&bd->bd_ail_st_list, &ai->ai_ail2_list); + } + + return list_empty(&ai->ai_ail1_list); +} + +void gfs2_ail1_start(struct gfs2_sbd *sdp, int flags) +{ + struct list_head *head = &sdp->sd_ail1_list; + u64 sync_gen; + struct list_head *first; + struct gfs2_ail *first_ai, *ai, *tmp; + int done = 0; + + gfs2_log_lock(sdp); + if (list_empty(head)) { + gfs2_log_unlock(sdp); + return; + } + sync_gen = sdp->sd_ail_sync_gen++; + + first = head->prev; + first_ai = list_entry(first, struct gfs2_ail, ai_list); + first_ai->ai_sync_gen = sync_gen; + gfs2_ail1_start_one(sdp, first_ai); /* This may drop log lock */ + + if (flags & DIO_ALL) + first = NULL; + + while(!done) { + if (first && (head->prev != first || + gfs2_ail1_empty_one(sdp, first_ai, 0))) + break; + + done = 1; + list_for_each_entry_safe_reverse(ai, tmp, head, ai_list) { + if (ai->ai_sync_gen >= sync_gen) + continue; + ai->ai_sync_gen = sync_gen; + gfs2_ail1_start_one(sdp, ai); /* This may drop log lock */ + done = 0; + break; + } + } + + gfs2_log_unlock(sdp); +} + +int gfs2_ail1_empty(struct gfs2_sbd *sdp, int flags) +{ + struct gfs2_ail *ai, *s; + int ret; + + gfs2_log_lock(sdp); + + list_for_each_entry_safe_reverse(ai, s, &sdp->sd_ail1_list, ai_list) { + if (gfs2_ail1_empty_one(sdp, ai, flags)) + list_move(&ai->ai_list, &sdp->sd_ail2_list); + else if (!(flags & DIO_ALL)) + break; + } + + ret = list_empty(&sdp->sd_ail1_list); + + gfs2_log_unlock(sdp); + + return ret; +} + + +/** + * gfs2_ail2_empty_one - Check whether or not a trans in the AIL has been synced + * @sdp: the filesystem + * @ai: the AIL entry + * + */ + +static void gfs2_ail2_empty_one(struct gfs2_sbd *sdp, struct gfs2_ail *ai) +{ + struct list_head *head = &ai->ai_ail2_list; + struct gfs2_bufdata *bd; + + while (!list_empty(head)) { + bd = list_entry(head->prev, struct gfs2_bufdata, + bd_ail_st_list); + gfs2_assert(sdp, bd->bd_ail == ai); + bd->bd_ail = NULL; + list_del(&bd->bd_ail_st_list); + list_del(&bd->bd_ail_gl_list); + atomic_dec(&bd->bd_gl->gl_ail_count); + brelse(bd->bd_bh); + } +} + +static void ail2_empty(struct gfs2_sbd *sdp, unsigned int new_tail) +{ + struct gfs2_ail *ai, *safe; + unsigned int old_tail = sdp->sd_log_tail; + int wrap = (new_tail < old_tail); + int a, b, rm; + + gfs2_log_lock(sdp); + + list_for_each_entry_safe(ai, safe, &sdp->sd_ail2_list, ai_list) { + a = (old_tail <= ai->ai_first); + b = (ai->ai_first < new_tail); + rm = (wrap) ? (a || b) : (a && b); + if (!rm) + continue; + + gfs2_ail2_empty_one(sdp, ai); + list_del(&ai->ai_list); + gfs2_assert_warn(sdp, list_empty(&ai->ai_ail1_list)); + gfs2_assert_warn(sdp, list_empty(&ai->ai_ail2_list)); + kfree(ai); + } + + gfs2_log_unlock(sdp); +} + +/** + * gfs2_log_reserve - Make a log reservation + * @sdp: The GFS2 superblock + * @blks: The number of blocks to reserve + * + * Returns: errno + */ + +int gfs2_log_reserve(struct gfs2_sbd *sdp, unsigned int blks) +{ + unsigned int try = 0; + + if (gfs2_assert_warn(sdp, blks) || + gfs2_assert_warn(sdp, blks <= sdp->sd_jdesc->jd_blocks)) + return -EINVAL; + + mutex_lock(&sdp->sd_log_reserve_mutex); + gfs2_log_lock(sdp); + while(sdp->sd_log_blks_free <= blks) { + gfs2_log_unlock(sdp); + gfs2_ail1_empty(sdp, 0); + gfs2_log_flush(sdp, NULL); + + if (try++) + gfs2_ail1_start(sdp, 0); + gfs2_log_lock(sdp); + } + sdp->sd_log_blks_free -= blks; + gfs2_log_unlock(sdp); + mutex_unlock(&sdp->sd_log_reserve_mutex); + + down_read(&sdp->sd_log_flush_lock); + + return 0; +} + +/** + * gfs2_log_release - Release a given number of log blocks + * @sdp: The GFS2 superblock + * @blks: The number of blocks + * + */ + +void gfs2_log_release(struct gfs2_sbd *sdp, unsigned int blks) +{ + + gfs2_log_lock(sdp); + sdp->sd_log_blks_free += blks; + gfs2_assert_withdraw(sdp, + sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks); + gfs2_log_unlock(sdp); + up_read(&sdp->sd_log_flush_lock); +} + +static u64 log_bmap(struct gfs2_sbd *sdp, unsigned int lbn) +{ + int error; + struct buffer_head bh_map; + + error = gfs2_block_map(sdp->sd_jdesc->jd_inode, lbn, 0, &bh_map, 1); + if (error || !bh_map.b_blocknr) + printk(KERN_INFO "error=%d, dbn=%llu lbn=%u", error, bh_map.b_blocknr, lbn); + gfs2_assert_withdraw(sdp, !error && bh_map.b_blocknr); + + return bh_map.b_blocknr; +} + +/** + * log_distance - Compute distance between two journal blocks + * @sdp: The GFS2 superblock + * @newer: The most recent journal block of the pair + * @older: The older journal block of the pair + * + * Compute the distance (in the journal direction) between two + * blocks in the journal + * + * Returns: the distance in blocks + */ + +static inline unsigned int log_distance(struct gfs2_sbd *sdp, unsigned int newer, + unsigned int older) +{ + int dist; + + dist = newer - older; + if (dist < 0) + dist += sdp->sd_jdesc->jd_blocks; + + return dist; +} + +static unsigned int current_tail(struct gfs2_sbd *sdp) +{ + struct gfs2_ail *ai; + unsigned int tail; + + gfs2_log_lock(sdp); + + if (list_empty(&sdp->sd_ail1_list)) { + tail = sdp->sd_log_head; + } else { + ai = list_entry(sdp->sd_ail1_list.prev, struct gfs2_ail, ai_list); + tail = ai->ai_first; + } + + gfs2_log_unlock(sdp); + + return tail; +} + +static inline void log_incr_head(struct gfs2_sbd *sdp) +{ + if (sdp->sd_log_flush_head == sdp->sd_log_tail) + gfs2_assert_withdraw(sdp, sdp->sd_log_flush_head == sdp->sd_log_head); + + if (++sdp->sd_log_flush_head == sdp->sd_jdesc->jd_blocks) { + sdp->sd_log_flush_head = 0; + sdp->sd_log_flush_wrapped = 1; + } +} + +/** + * gfs2_log_get_buf - Get and initialize a buffer to use for log control data + * @sdp: The GFS2 superblock + * + * Returns: the buffer_head + */ + +struct buffer_head *gfs2_log_get_buf(struct gfs2_sbd *sdp) +{ + u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head); + struct gfs2_log_buf *lb; + struct buffer_head *bh; + + lb = kzalloc(sizeof(struct gfs2_log_buf), GFP_NOFS | __GFP_NOFAIL); + list_add(&lb->lb_list, &sdp->sd_log_flush_list); + + bh = lb->lb_bh = sb_getblk(sdp->sd_vfs, blkno); + lock_buffer(bh); + memset(bh->b_data, 0, bh->b_size); + set_buffer_uptodate(bh); + clear_buffer_dirty(bh); + unlock_buffer(bh); + + log_incr_head(sdp); + + return bh; +} + +/** + * gfs2_log_fake_buf - Build a fake buffer head to write metadata buffer to log + * @sdp: the filesystem + * @data: the data the buffer_head should point to + * + * Returns: the log buffer descriptor + */ + +struct buffer_head *gfs2_log_fake_buf(struct gfs2_sbd *sdp, + struct buffer_head *real) +{ + u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head); + struct gfs2_log_buf *lb; + struct buffer_head *bh; + + lb = kzalloc(sizeof(struct gfs2_log_buf), GFP_NOFS | __GFP_NOFAIL); + list_add(&lb->lb_list, &sdp->sd_log_flush_list); + lb->lb_real = real; + + bh = lb->lb_bh = alloc_buffer_head(GFP_NOFS | __GFP_NOFAIL); + atomic_set(&bh->b_count, 1); + bh->b_state = (1 << BH_Mapped) | (1 << BH_Uptodate); + set_bh_page(bh, real->b_page, bh_offset(real)); + bh->b_blocknr = blkno; + bh->b_size = sdp->sd_sb.sb_bsize; + bh->b_bdev = sdp->sd_vfs->s_bdev; + + log_incr_head(sdp); + + return bh; +} + +static void log_pull_tail(struct gfs2_sbd *sdp, unsigned int new_tail, int pull) +{ + unsigned int dist = log_distance(sdp, new_tail, sdp->sd_log_tail); + + ail2_empty(sdp, new_tail); + + gfs2_log_lock(sdp); + sdp->sd_log_blks_free += dist - (pull ? 1 : 0); + gfs2_assert_withdraw(sdp, sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks); + gfs2_log_unlock(sdp); + + sdp->sd_log_tail = new_tail; +} + +/** + * log_write_header - Get and initialize a journal header buffer + * @sdp: The GFS2 superblock + * + * Returns: the initialized log buffer descriptor + */ + +static void log_write_header(struct gfs2_sbd *sdp, u32 flags, int pull) +{ + u64 blkno = log_bmap(sdp, sdp->sd_log_flush_head); + struct buffer_head *bh; + struct gfs2_log_header *lh; + unsigned int tail; + u32 hash; + + bh = sb_getblk(sdp->sd_vfs, blkno); + lock_buffer(bh); + memset(bh->b_data, 0, bh->b_size); + set_buffer_uptodate(bh); + clear_buffer_dirty(bh); + unlock_buffer(bh); + + gfs2_ail1_empty(sdp, 0); + tail = current_tail(sdp); + + lh = (struct gfs2_log_header *)bh->b_data; + memset(lh, 0, sizeof(struct gfs2_log_header)); + lh->lh_header.mh_magic = cpu_to_be32(GFS2_MAGIC); + lh->lh_header.mh_type = cpu_to_be32(GFS2_METATYPE_LH); + lh->lh_header.mh_format = cpu_to_be32(GFS2_FORMAT_LH); + lh->lh_sequence = cpu_to_be64(sdp->sd_log_sequence++); + lh->lh_flags = cpu_to_be32(flags); + lh->lh_tail = cpu_to_be32(tail); + lh->lh_blkno = cpu_to_be32(sdp->sd_log_flush_head); + hash = gfs2_disk_hash(bh->b_data, sizeof(struct gfs2_log_header)); + lh->lh_hash = cpu_to_be32(hash); + + set_buffer_dirty(bh); + if (sync_dirty_buffer(bh)) + gfs2_io_error_bh(sdp, bh); + brelse(bh); + + if (sdp->sd_log_tail != tail) + log_pull_tail(sdp, tail, pull); + else + gfs2_assert_withdraw(sdp, !pull); + + sdp->sd_log_idle = (tail == sdp->sd_log_flush_head); + log_incr_head(sdp); +} + +static void log_flush_commit(struct gfs2_sbd *sdp) +{ + struct list_head *head = &sdp->sd_log_flush_list; + struct gfs2_log_buf *lb; + struct buffer_head *bh; + + while (!list_empty(head)) { + lb = list_entry(head->next, struct gfs2_log_buf, lb_list); + list_del(&lb->lb_list); + bh = lb->lb_bh; + + wait_on_buffer(bh); + if (!buffer_uptodate(bh)) + gfs2_io_error_bh(sdp, bh); + if (lb->lb_real) { + while (atomic_read(&bh->b_count) != 1) /* Grrrr... */ + schedule(); + free_buffer_head(bh); + } else + brelse(bh); + kfree(lb); + } + + log_write_header(sdp, 0, 0); +} + +/** + * gfs2_log_flush - flush incore transaction(s) + * @sdp: the filesystem + * @gl: The glock structure to flush. If NULL, flush the whole incore log + * + */ + +void gfs2_log_flush(struct gfs2_sbd *sdp, struct gfs2_glock *gl) +{ + struct gfs2_ail *ai; + + down_write(&sdp->sd_log_flush_lock); + + if (gl) { + gfs2_log_lock(sdp); + if (list_empty(&gl->gl_le.le_list)) { + gfs2_log_unlock(sdp); + up_write(&sdp->sd_log_flush_lock); + return; + } + gfs2_log_unlock(sdp); + } + + ai = kzalloc(sizeof(struct gfs2_ail), GFP_NOFS | __GFP_NOFAIL); + INIT_LIST_HEAD(&ai->ai_ail1_list); + INIT_LIST_HEAD(&ai->ai_ail2_list); + + gfs2_assert_withdraw(sdp, sdp->sd_log_num_buf == sdp->sd_log_commited_buf); + gfs2_assert_withdraw(sdp, + sdp->sd_log_num_revoke == sdp->sd_log_commited_revoke); + + sdp->sd_log_flush_head = sdp->sd_log_head; + sdp->sd_log_flush_wrapped = 0; + ai->ai_first = sdp->sd_log_flush_head; + + lops_before_commit(sdp); + if (!list_empty(&sdp->sd_log_flush_list)) + log_flush_commit(sdp); + else if (sdp->sd_log_tail != current_tail(sdp) && !sdp->sd_log_idle) + log_write_header(sdp, 0, PULL); + lops_after_commit(sdp, ai); + sdp->sd_log_head = sdp->sd_log_flush_head; + + sdp->sd_log_blks_free -= sdp->sd_log_num_hdrs; + + sdp->sd_log_blks_reserved = 0; + sdp->sd_log_commited_buf = 0; + sdp->sd_log_num_hdrs = 0; + sdp->sd_log_commited_revoke = 0; + + gfs2_log_lock(sdp); + if (!list_empty(&ai->ai_ail1_list)) { + list_add(&ai->ai_list, &sdp->sd_ail1_list); + ai = NULL; + } + gfs2_log_unlock(sdp); + + sdp->sd_vfs->s_dirt = 0; + up_write(&sdp->sd_log_flush_lock); + + kfree(ai); +} + +static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr) +{ + unsigned int reserved = 0; + unsigned int old; + + gfs2_log_lock(sdp); + + sdp->sd_log_commited_buf += tr->tr_num_buf_new - tr->tr_num_buf_rm; + gfs2_assert_withdraw(sdp, ((int)sdp->sd_log_commited_buf) >= 0); + sdp->sd_log_commited_revoke += tr->tr_num_revoke - tr->tr_num_revoke_rm; + gfs2_assert_withdraw(sdp, ((int)sdp->sd_log_commited_revoke) >= 0); + + if (sdp->sd_log_commited_buf) + reserved += sdp->sd_log_commited_buf; + if (sdp->sd_log_commited_revoke) + reserved += gfs2_struct2blk(sdp, sdp->sd_log_commited_revoke, + sizeof(u64)); + if (reserved) + reserved++; + + old = sdp->sd_log_blks_free; + sdp->sd_log_blks_free += tr->tr_reserved - + (reserved - sdp->sd_log_blks_reserved); + + gfs2_assert_withdraw(sdp, sdp->sd_log_blks_free >= old); + gfs2_assert_withdraw(sdp, + sdp->sd_log_blks_free <= sdp->sd_jdesc->jd_blocks + + sdp->sd_log_num_hdrs); + + sdp->sd_log_blks_reserved = reserved; + + gfs2_log_unlock(sdp); +} + +/** + * gfs2_log_commit - Commit a transaction to the log + * @sdp: the filesystem + * @tr: the transaction + * + * Returns: errno + */ + +void gfs2_log_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr) +{ + log_refund(sdp, tr); + lops_incore_commit(sdp, tr); + + sdp->sd_vfs->s_dirt = 1; + up_read(&sdp->sd_log_flush_lock); + + gfs2_log_lock(sdp); + if (sdp->sd_log_num_buf > gfs2_tune_get(sdp, gt_incore_log_blocks)) { + gfs2_log_unlock(sdp); + gfs2_log_flush(sdp, NULL); + } else { + gfs2_log_unlock(sdp); + } +} + +/** + * gfs2_log_shutdown - write a shutdown header into a journal + * @sdp: the filesystem + * + */ + +void gfs2_log_shutdown(struct gfs2_sbd *sdp) +{ + down_write(&sdp->sd_log_flush_lock); + + gfs2_assert_withdraw(sdp, !sdp->sd_log_blks_reserved); + gfs2_assert_withdraw(sdp, !sdp->sd_log_num_gl); + gfs2_assert_withdraw(sdp, !sdp->sd_log_num_buf); + gfs2_assert_withdraw(sdp, !sdp->sd_log_num_jdata); + gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke); + gfs2_assert_withdraw(sdp, !sdp->sd_log_num_rg); + gfs2_assert_withdraw(sdp, !sdp->sd_log_num_databuf); + gfs2_assert_withdraw(sdp, !sdp->sd_log_num_hdrs); + gfs2_assert_withdraw(sdp, list_empty(&sdp->sd_ail1_list)); + + sdp->sd_log_flush_head = sdp->sd_log_head; + sdp->sd_log_flush_wrapped = 0; + + log_write_header(sdp, GFS2_LOG_HEAD_UNMOUNT, 0); + + gfs2_assert_warn(sdp, sdp->sd_log_blks_free == sdp->sd_jdesc->jd_blocks); + gfs2_assert_warn(sdp, sdp->sd_log_head == sdp->sd_log_tail); + gfs2_assert_warn(sdp, list_empty(&sdp->sd_ail2_list)); + + sdp->sd_log_head = sdp->sd_log_flush_head; + sdp->sd_log_tail = sdp->sd_log_head; + + up_write(&sdp->sd_log_flush_lock); +} + |