diff options
-rw-r--r-- | fs/xfs/xfs_inode.c | 137 |
1 files changed, 65 insertions, 72 deletions
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c index 2bc22790d65..ca12acb9039 100644 --- a/fs/xfs/xfs_inode.c +++ b/fs/xfs/xfs_inode.c @@ -1464,51 +1464,50 @@ xfs_itruncate_start( } /* - * Shrink the file to the given new_size. The new - * size must be smaller than the current size. - * This will free up the underlying blocks - * in the removed range after a call to xfs_itruncate_start() - * or xfs_atruncate_start(). + * Shrink the file to the given new_size. The new size must be smaller than + * the current size. This will free up the underlying blocks in the removed + * range after a call to xfs_itruncate_start() or xfs_atruncate_start(). * - * The transaction passed to this routine must have made - * a permanent log reservation of at least XFS_ITRUNCATE_LOG_RES. - * This routine may commit the given transaction and - * start new ones, so make sure everything involved in - * the transaction is tidy before calling here. - * Some transaction will be returned to the caller to be - * committed. The incoming transaction must already include - * the inode, and both inode locks must be held exclusively. - * The inode must also be "held" within the transaction. On - * return the inode will be "held" within the returned transaction. - * This routine does NOT require any disk space to be reserved - * for it within the transaction. + * The transaction passed to this routine must have made a permanent log + * reservation of at least XFS_ITRUNCATE_LOG_RES. This routine may commit the + * given transaction and start new ones, so make sure everything involved in + * the transaction is tidy before calling here. Some transaction will be + * returned to the caller to be committed. The incoming transaction must + * already include the inode, and both inode locks must be held exclusively. + * The inode must also be "held" within the transaction. On return the inode + * will be "held" within the returned transaction. This routine does NOT + * require any disk space to be reserved for it within the transaction. * - * The fork parameter must be either xfs_attr_fork or xfs_data_fork, - * and it indicates the fork which is to be truncated. For the - * attribute fork we only support truncation to size 0. + * The fork parameter must be either xfs_attr_fork or xfs_data_fork, and it + * indicates the fork which is to be truncated. For the attribute fork we only + * support truncation to size 0. * - * We use the sync parameter to indicate whether or not the first - * transaction we perform might have to be synchronous. For the attr fork, - * it needs to be so if the unlink of the inode is not yet known to be - * permanent in the log. This keeps us from freeing and reusing the - * blocks of the attribute fork before the unlink of the inode becomes - * permanent. + * We use the sync parameter to indicate whether or not the first transaction + * we perform might have to be synchronous. For the attr fork, it needs to be + * so if the unlink of the inode is not yet known to be permanent in the log. + * This keeps us from freeing and reusing the blocks of the attribute fork + * before the unlink of the inode becomes permanent. * - * For the data fork, we normally have to run synchronously if we're - * being called out of the inactive path or we're being called - * out of the create path where we're truncating an existing file. - * Either way, the truncate needs to be sync so blocks don't reappear - * in the file with altered data in case of a crash. wsync filesystems - * can run the first case async because anything that shrinks the inode - * has to run sync so by the time we're called here from inactive, the - * inode size is permanently set to 0. + * For the data fork, we normally have to run synchronously if we're being + * called out of the inactive path or we're being called out of the create path + * where we're truncating an existing file. Either way, the truncate needs to + * be sync so blocks don't reappear in the file with altered data in case of a + * crash. wsync filesystems can run the first case async because anything that + * shrinks the inode has to run sync so by the time we're called here from + * inactive, the inode size is permanently set to 0. * - * Calls from the truncate path always need to be sync unless we're - * in a wsync filesystem and the file has already been unlinked. + * Calls from the truncate path always need to be sync unless we're in a wsync + * filesystem and the file has already been unlinked. * - * The caller is responsible for correctly setting the sync parameter. - * It gets too hard for us to guess here which path we're being called - * out of just based on inode state. + * The caller is responsible for correctly setting the sync parameter. It gets + * too hard for us to guess here which path we're being called out of just + * based on inode state. + * + * If we get an error, we must return with the inode locked and linked into the + * current transaction. This keeps things simple for the higher level code, + * because it always knows that the inode is locked and held in the transaction + * that returns to it whether errors occur or not. We don't mark the inode + * dirty on error so that transactions can be easily aborted if possible. */ int xfs_itruncate_finish( @@ -1687,45 +1686,51 @@ xfs_itruncate_finish( */ error = xfs_bmap_finish(tp, &free_list, &committed); ntp = *tp; + if (committed) { + /* link the inode into the next xact in the chain */ + xfs_trans_ijoin(ntp, ip, + XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL); + xfs_trans_ihold(ntp, ip); + } + if (error) { /* - * If the bmap finish call encounters an error, - * return to the caller where the transaction - * can be properly aborted. We just need to - * make sure we're not holding any resources - * that we were not when we came in. + * If the bmap finish call encounters an error, return + * to the caller where the transaction can be properly + * aborted. We just need to make sure we're not + * holding any resources that we were not when we came + * in. * - * Aborting from this point might lose some - * blocks in the file system, but oh well. + * Aborting from this point might lose some blocks in + * the file system, but oh well. */ xfs_bmap_cancel(&free_list); - if (committed) - goto error_join; return error; } if (committed) { /* - * The first xact was committed, so add the inode to - * the new one. Mark it dirty so it will be logged and + * Mark the inode dirty so it will be logged and * moved forward in the log as part of every commit. */ - xfs_trans_ijoin(ntp, ip, - XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL); - xfs_trans_ihold(ntp, ip); xfs_trans_log_inode(ntp, ip, XFS_ILOG_CORE); } + ntp = xfs_trans_dup(ntp); error = xfs_trans_commit(*tp, 0); *tp = ntp; - if (error) - goto error_join; - error = xfs_trans_reserve(ntp, 0, XFS_ITRUNCATE_LOG_RES(mp), 0, - XFS_TRANS_PERM_LOG_RES, - XFS_ITRUNCATE_LOG_COUNT); - if (error) - goto error_join; + /* link the inode into the next transaction in the chain */ + xfs_trans_ijoin(ntp, ip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL); + xfs_trans_ihold(ntp, ip); + + if (!error) + error = xfs_trans_reserve(ntp, 0, + XFS_ITRUNCATE_LOG_RES(mp), 0, + XFS_TRANS_PERM_LOG_RES, + XFS_ITRUNCATE_LOG_COUNT); + if (error) + return error; } /* * Only update the size in the case of the data fork, but @@ -1757,18 +1762,6 @@ xfs_itruncate_finish( (ip->i_d.di_nextents == 0)); xfs_itrunc_trace(XFS_ITRUNC_FINISH2, ip, 0, new_size, 0, 0); return 0; - -error_join: - /* - * Add the inode being truncated to the next chained transaction. This - * keeps things simple for the higher level code, because it always - * knows that the inode is locked and held in the transaction that - * returns to it whether errors occur or not. We don't mark the inode - * dirty so that this transaction can be easily aborted if possible. - */ - xfs_trans_ijoin(ntp, ip, XFS_ILOCK_EXCL | XFS_IOLOCK_EXCL); - xfs_trans_ihold(ntp, ip); - return error; } |