From: Chris Mason <mason@suse.com>
reiserfs support for nested transactions. This originally came from Peter
Braam for 2.4.x and was ported forward by Jeff Mahoney.
---
25-akpm/fs/reiserfs/inode.c | 4 +
25-akpm/fs/reiserfs/journal.c | 78 +++++++++++++++++++++++++++++++--
25-akpm/fs/reiserfs/namei.c | 1
25-akpm/include/linux/reiserfs_fs_sb.h | 12 +++--
4 files changed, 86 insertions(+), 9 deletions(-)
diff -puN fs/reiserfs/inode.c~reiserfs-nesting-02 fs/reiserfs/inode.c
--- 25/fs/reiserfs/inode.c~reiserfs-nesting-02 Wed Mar 24 15:14:28 2004
+++ 25-akpm/fs/reiserfs/inode.c Wed Mar 24 15:14:28 2004
@@ -206,6 +206,10 @@ static int file_capable (struct inode *
struct super_block *s = th->t_super ;
int len = th->t_blocks_allocated ;
+ /* we cannot restart while nested */
+ if (th->t_refcount > 1) {
+ return ;
+ }
pathrelse(path) ;
reiserfs_update_sd(th, inode) ;
journal_end(th, s, len) ;
diff -puN fs/reiserfs/journal.c~reiserfs-nesting-02 fs/reiserfs/journal.c
--- 25/fs/reiserfs/journal.c~reiserfs-nesting-02 Wed Mar 24 15:14:28 2004
+++ 25-akpm/fs/reiserfs/journal.c Wed Mar 24 15:14:28 2004
@@ -2157,6 +2157,9 @@ int journal_transaction_should_end(struc
time_t now = get_seconds() ;
if (reiserfs_dont_log(th->t_super))
return 0 ;
+ /* cannot restart while nested */
+ if (th->t_refcount > 1)
+ return 0 ;
if ( SB_JOURNAL(th->t_super)->j_must_wait > 0 ||
(SB_JOURNAL(th->t_super)->j_len_alloc + new_alloc) >= SB_JOURNAL_MAX_BATCH(th->t_super) ||
atomic_read(&(SB_JOURNAL(th->t_super)->j_jlock)) ||
@@ -2212,6 +2215,9 @@ static int do_journal_begin_r(struct rei
return 0 ;
}
PROC_INFO_INC( p_s_sb, journal.journal_being );
+ /* set here for journal_join */
+ th->t_refcount = 1;
+ th->t_super = p_s_sb ;
relock:
lock_journal(p_s_sb) ;
@@ -2268,9 +2274,7 @@ relock:
SB_JOURNAL(p_s_sb)->j_len_alloc += nblocks ;
th->t_blocks_logged = 0 ;
th->t_blocks_allocated = nblocks ;
- th->t_super = p_s_sb ;
th->t_trans_id = SB_JOURNAL(p_s_sb)->j_trans_id ;
- th->t_caller = "Unknown" ;
unlock_journal(p_s_sb) ;
p_s_sb->s_dirt = 1;
return 0 ;
@@ -2278,11 +2282,47 @@ relock:
static int journal_join(struct reiserfs_transaction_handle *th, struct super_block *p_s_sb, unsigned long nblocks) {
+ struct reiserfs_transaction_handle *cur_th = current->journal_info;
+
+ /* this keeps do_journal_end from NULLing out the current->journal_info
+ ** pointer
+ */
+ th->t_handle_save = cur_th ;
+ if (cur_th && cur_th->t_refcount > 1) {
+ BUG() ;
+ }
return do_journal_begin_r(th, p_s_sb, nblocks, 1) ;
}
int journal_begin(struct reiserfs_transaction_handle *th, struct super_block * p_s_sb, unsigned long nblocks) {
- return do_journal_begin_r(th, p_s_sb, nblocks, 0) ;
+ struct reiserfs_transaction_handle *cur_th = current->journal_info ;
+ int ret ;
+
+ th->t_handle_save = NULL ;
+ if (cur_th) {
+ /* we are nesting into the current transaction */
+ if (cur_th->t_super == p_s_sb) {
+ cur_th->t_refcount++ ;
+ memcpy(th, cur_th, sizeof(*th));
+ if (th->t_refcount <= 1)
+ printk("BAD: refcount <= 1, but journal_info != 0\n");
+ return 0;
+ } else {
+ /* we've ended up with a handle from a different filesystem.
+ ** save it and restore on journal_end. This should never
+ ** really happen...
+ */
+ reiserfs_warning("clm-2100: nesting info a different FS\n") ;
+ th->t_handle_save = current->journal_info ;
+ current->journal_info = th;
+ }
+ } else {
+ current->journal_info = th;
+ }
+ ret = do_journal_begin_r(th, p_s_sb, nblocks, 0) ;
+ if (current->journal_info != th)
+ BUG() ;
+ return ret ;
}
/* not used at all */
@@ -2422,7 +2462,26 @@ int journal_mark_dirty_nolog(struct reis
}
int journal_end(struct reiserfs_transaction_handle *th, struct super_block *p_s_sb, unsigned long nblocks) {
- return do_journal_end(th, p_s_sb, nblocks, 0) ;
+ if (!current->journal_info && th->t_refcount > 1)
+ printk("REISER-NESTING: th NULL, refcount %d\n", th->t_refcount);
+ if (th->t_refcount > 1) {
+ struct reiserfs_transaction_handle *cur_th = current->journal_info ;
+
+ /* we aren't allowed to close a nested transaction on a different
+ ** filesystem from the one in the task struct
+ */
+ if (cur_th->t_super != th->t_super)
+ BUG() ;
+
+ th->t_refcount--;
+ if (th != cur_th) {
+ memcpy(current->journal_info, th, sizeof(*th));
+ th->t_trans_id = 0;
+ }
+ return 0;
+ } else {
+ return do_journal_end(th, p_s_sb, nblocks, 0) ;
+ }
}
/* removes from the current transaction, relsing and descrementing any counters.
@@ -2520,6 +2579,10 @@ static int can_dirty(struct reiserfs_jou
*/
int journal_end_sync(struct reiserfs_transaction_handle *th, struct super_block *p_s_sb, unsigned long nblocks) {
+ /* you can sync while nested, very, very bad */
+ if (th->t_refcount > 1) {
+ BUG() ;
+ }
if (SB_JOURNAL(p_s_sb)->j_len == 0) {
reiserfs_prepare_for_journal(p_s_sb, SB_BUFFER_WITH_SB(p_s_sb), 1) ;
journal_mark_dirty(th, p_s_sb, SB_BUFFER_WITH_SB(p_s_sb)) ;
@@ -2901,6 +2964,10 @@ static int do_journal_end(struct reiserf
struct reiserfs_super_block *rs ;
int trans_half ;
+ if (th->t_refcount > 1)
+ BUG() ;
+
+ current->journal_info = th->t_handle_save;
if (reiserfs_dont_log(th->t_super)) {
return 0 ;
}
@@ -2938,8 +3005,11 @@ static int do_journal_end(struct reiserf
}
#ifdef REISERFS_PREALLOCATE
+ /* quota ops might need to nest, setup the journal_info pointer for them */
+ current->journal_info = th ;
reiserfs_discard_all_prealloc(th); /* it should not involve new blocks into
* the transaction */
+ current->journal_info = th->t_handle_save ;
#endif
rs = SB_DISK_SUPER_BLOCK(p_s_sb) ;
diff -puN fs/reiserfs/namei.c~reiserfs-nesting-02 fs/reiserfs/namei.c
--- 25/fs/reiserfs/namei.c~reiserfs-nesting-02 Wed Mar 24 15:14:28 2004
+++ 25-akpm/fs/reiserfs/namei.c Wed Mar 24 15:14:28 2004
@@ -575,7 +575,6 @@ static int reiserfs_create (struct inode
reiserfs_write_lock(dir->i_sb);
journal_begin(&th, dir->i_sb, jbegin_count) ;
- th.t_caller = "create" ;
retval = reiserfs_new_inode (&th, dir, mode, 0, 0/*i_size*/, dentry, inode);
if (retval) {
goto out_failed;
diff -puN include/linux/reiserfs_fs_sb.h~reiserfs-nesting-02 include/linux/reiserfs_fs_sb.h
--- 25/include/linux/reiserfs_fs_sb.h~reiserfs-nesting-02 Wed Mar 24 15:14:28 2004
+++ 25-akpm/include/linux/reiserfs_fs_sb.h Wed Mar 24 15:14:28 2004
@@ -157,13 +157,17 @@ struct reiserfs_list_bitmap {
** transaction handle which is passed around for all journal calls
*/
struct reiserfs_transaction_handle {
- /* ifdef it. -Hans */
- char *t_caller ; /* debugging use */
+ struct super_block *t_super ; /* super for this FS when journal_begin was
+ called. saves calls to reiserfs_get_super
+ also used by nested transactions to make
+ sure they are nesting on the right FS
+ _must_ be first in the handle
+ */
+ int t_refcount;
int t_blocks_logged ; /* number of blocks this writer has logged */
int t_blocks_allocated ; /* number of blocks this writer allocated */
unsigned long t_trans_id ; /* sanity check, equals the current trans id */
- struct super_block *t_super ; /* super for this FS when journal_begin was
- called. saves calls to reiserfs_get_super */
+ void *t_handle_save ; /* save existing current->journal_info */
int displace_new_blocks:1; /* if new block allocation occurres, that block
should be displaced from others */
_