From: Gang He <g...@suse.com> Subject: ocfs2: nowait aio support Return EAGAIN if any of the following checks fail for direct I/O:
- Cannot get the related locks immediately - Blocks are not allocated at the write location, it will trigger block allocation and block IO operations. [g...@suse.com: v2] Link: https://urldefense.proofpoint.com/v2/url?u=http-3A__lkml.kernel.org_r_1511944612-2D9629-2D4-2Dgit-2Dsend-2Demail-2Dghe-40suse.com&d=DwICAg&c=RoP1YumCXCgaWHvlZYR8PZh8Bv7qIrMUB65eapI_JnE&r=C7gAd4uDxlAvTdc0vmU6X8CMk6L2iDY8-HD0qT6Fo7Y&m=03axuTG8C4n44K1VY4yCWSg99FrknrLMs6_MlBfcfZU&s=bPQ5h9lbd8EtCwlBcfN_UJx6O1Fr6JiZUO7Ak2Igdds&e= Link: https://urldefense.proofpoint.com/v2/url?u=http-3A__lkml.kernel.org_r_1511775987-2D841-2D4-2Dgit-2Dsend-2Demail-2Dghe-40suse.com&d=DwICAg&c=RoP1YumCXCgaWHvlZYR8PZh8Bv7qIrMUB65eapI_JnE&r=C7gAd4uDxlAvTdc0vmU6X8CMk6L2iDY8-HD0qT6Fo7Y&m=03axuTG8C4n44K1VY4yCWSg99FrknrLMs6_MlBfcfZU&s=TX3FDWVXDkrHLxSD3HW3GW5igY6jogyX7Sf-OB5WrYk&e= Signed-off-by: Gang He <g...@suse.com> Cc: Mark Fasheh <mfas...@versity.com> Cc: Joel Becker <jl...@evilplan.org> Cc: Junxiao Bi <junxiao...@oracle.com> Cc: Joseph Qi <jiangqi...@gmail.com> Cc: Changwei Ge <ge.chang...@h3c.com> Signed-off-by: Andrew Morton <a...@linux-foundation.org> --- fs/ocfs2/dir.c | 2 fs/ocfs2/dlmglue.c | 20 ++++++-- fs/ocfs2/dlmglue.h | 2 fs/ocfs2/file.c | 95 ++++++++++++++++++++++++++++++--------- fs/ocfs2/mmap.c | 2 fs/ocfs2/ocfs2_trace.h | 10 ++-- 6 files changed, 99 insertions(+), 32 deletions(-) diff -puN fs/ocfs2/dir.c~ocfs2-nowait-aio-support fs/ocfs2/dir.c --- a/fs/ocfs2/dir.c~ocfs2-nowait-aio-support +++ a/fs/ocfs2/dir.c @@ -1957,7 +1957,7 @@ int ocfs2_readdir(struct file *file, str trace_ocfs2_readdir((unsigned long long)OCFS2_I(inode)->ip_blkno); - error = ocfs2_inode_lock_atime(inode, file->f_path.mnt, &lock_level); + error = ocfs2_inode_lock_atime(inode, file->f_path.mnt, &lock_level, 1); if (lock_level && error >= 0) { /* We release EX lock which used to update atime * and get PR lock again to reduce contention diff -puN fs/ocfs2/dlmglue.c~ocfs2-nowait-aio-support fs/ocfs2/dlmglue.c --- a/fs/ocfs2/dlmglue.c~ocfs2-nowait-aio-support +++ a/fs/ocfs2/dlmglue.c @@ -2515,13 +2515,18 @@ int ocfs2_inode_lock_with_page(struct in int ocfs2_inode_lock_atime(struct inode *inode, struct vfsmount *vfsmnt, - int *level) + int *level, int wait) { int ret; - ret = ocfs2_inode_lock(inode, NULL, 0); + if (wait) + ret = ocfs2_inode_lock(inode, NULL, 0); + else + ret = ocfs2_try_inode_lock(inode, NULL, 0); + if (ret < 0) { - mlog_errno(ret); + if (ret != -EAGAIN) + mlog_errno(ret); return ret; } @@ -2533,9 +2538,14 @@ int ocfs2_inode_lock_atime(struct inode struct buffer_head *bh = NULL; ocfs2_inode_unlock(inode, 0); - ret = ocfs2_inode_lock(inode, &bh, 1); + if (wait) + ret = ocfs2_inode_lock(inode, &bh, 1); + else + ret = ocfs2_try_inode_lock(inode, &bh, 1); + if (ret < 0) { - mlog_errno(ret); + if (ret != -EAGAIN) + mlog_errno(ret); return ret; } *level = 1; diff -puN fs/ocfs2/dlmglue.h~ocfs2-nowait-aio-support fs/ocfs2/dlmglue.h --- a/fs/ocfs2/dlmglue.h~ocfs2-nowait-aio-support +++ a/fs/ocfs2/dlmglue.h @@ -123,7 +123,7 @@ int ocfs2_try_open_lock(struct inode *in void ocfs2_open_unlock(struct inode *inode); int ocfs2_inode_lock_atime(struct inode *inode, struct vfsmount *vfsmnt, - int *level); + int *level, int wait); int ocfs2_inode_lock_full_nested(struct inode *inode, struct buffer_head **ret_bh, int ex, diff -puN fs/ocfs2/file.c~ocfs2-nowait-aio-support fs/ocfs2/file.c --- a/fs/ocfs2/file.c~ocfs2-nowait-aio-support +++ a/fs/ocfs2/file.c @@ -140,6 +140,8 @@ static int ocfs2_file_open(struct inode spin_unlock(&oi->ip_lock); } + file->f_mode |= FMODE_NOWAIT; + leave: return status; } @@ -2132,12 +2134,12 @@ out: } static int ocfs2_prepare_inode_for_write(struct file *file, - loff_t pos, - size_t count) + loff_t pos, size_t count, int wait) { - int ret = 0, meta_level = 0; + int ret = 0, meta_level = 0, overwrite_io = 0; struct dentry *dentry = file->f_path.dentry; struct inode *inode = d_inode(dentry); + struct buffer_head *di_bh = NULL; loff_t end; /* @@ -2145,13 +2147,40 @@ static int ocfs2_prepare_inode_for_write * if we need to make modifications here. */ for(;;) { - ret = ocfs2_inode_lock(inode, NULL, meta_level); + if (wait) + ret = ocfs2_inode_lock(inode, NULL, meta_level); + else + ret = ocfs2_try_inode_lock(inode, + overwrite_io ? NULL : &di_bh, meta_level); if (ret < 0) { meta_level = -1; - mlog_errno(ret); + if (ret != -EAGAIN) + mlog_errno(ret); goto out; } + /* + * Check if IO will overwrite allocated blocks in case + * IOCB_NOWAIT flag is set. + */ + if (!wait && !overwrite_io) { + overwrite_io = 1; + if (!down_read_trylock(&OCFS2_I(inode)->ip_alloc_sem)) { + ret = -EAGAIN; + goto out_unlock; + } + + ret = ocfs2_overwrite_io(inode, di_bh, pos, count); + brelse(di_bh); + di_bh = NULL; + up_read(&OCFS2_I(inode)->ip_alloc_sem); + if (ret < 0) { + if (ret != -EAGAIN) + mlog_errno(ret); + goto out_unlock; + } + } + /* Clear suid / sgid if necessary. We do this here * instead of later in the write path because * remove_suid() calls ->setattr without any hint that @@ -2199,7 +2228,9 @@ static int ocfs2_prepare_inode_for_write out_unlock: trace_ocfs2_prepare_inode_for_write(OCFS2_I(inode)->ip_blkno, - pos, count); + pos, count, wait); + + brelse(di_bh); if (meta_level >= 0) ocfs2_inode_unlock(inode, meta_level); @@ -2211,7 +2242,7 @@ out: static ssize_t ocfs2_file_write_iter(struct kiocb *iocb, struct iov_iter *from) { - int direct_io, rw_level; + int rw_level; ssize_t written = 0; ssize_t ret; size_t count = iov_iter_count(from); @@ -2223,6 +2254,8 @@ static ssize_t ocfs2_file_write_iter(str void *saved_ki_complete = NULL; int append_write = ((iocb->ki_pos + count) >= i_size_read(inode) ? 1 : 0); + int direct_io = iocb->ki_flags & IOCB_DIRECT ? 1 : 0; + int nowait = iocb->ki_flags & IOCB_NOWAIT ? 1 : 0; trace_ocfs2_file_aio_write(inode, file, file->f_path.dentry, (unsigned long long)OCFS2_I(inode)->ip_blkno, @@ -2230,12 +2263,17 @@ static ssize_t ocfs2_file_write_iter(str file->f_path.dentry->d_name.name, (unsigned int)from->nr_segs); /* GRRRRR */ + if (!direct_io && nowait) + return -EOPNOTSUPP; + if (count == 0) return 0; - direct_io = iocb->ki_flags & IOCB_DIRECT ? 1 : 0; - - inode_lock(inode); + if (direct_io && nowait) { + if (!inode_trylock(inode)) + return -EAGAIN; + } else + inode_lock(inode); /* * Concurrent O_DIRECT writes are allowed with @@ -2244,9 +2282,13 @@ static ssize_t ocfs2_file_write_iter(str */ rw_level = (!direct_io || full_coherency || append_write); - ret = ocfs2_rw_lock(inode, rw_level); + if (direct_io && nowait) + ret = ocfs2_try_rw_lock(inode, rw_level); + else + ret = ocfs2_rw_lock(inode, rw_level); if (ret < 0) { - mlog_errno(ret); + if (ret != -EAGAIN) + mlog_errno(ret); goto out_mutex; } @@ -2260,9 +2302,13 @@ static ssize_t ocfs2_file_write_iter(str * other nodes to drop their caches. Buffered I/O * already does this in write_begin(). */ - ret = ocfs2_inode_lock(inode, NULL, 1); + if (nowait) + ret = ocfs2_try_inode_lock(inode, NULL, 1); + else + ret = ocfs2_inode_lock(inode, NULL, 1); if (ret < 0) { - mlog_errno(ret); + if (ret != -EAGAIN) + mlog_errno(ret); goto out; } @@ -2277,9 +2323,10 @@ static ssize_t ocfs2_file_write_iter(str } count = ret; - ret = ocfs2_prepare_inode_for_write(file, iocb->ki_pos, count); + ret = ocfs2_prepare_inode_for_write(file, iocb->ki_pos, count, !nowait); if (ret < 0) { - mlog_errno(ret); + if (ret != -EAGAIN) + mlog_errno(ret); goto out; } @@ -2355,6 +2402,7 @@ static ssize_t ocfs2_file_read_iter(stru int ret = 0, rw_level = -1, lock_level = 0; struct file *filp = iocb->ki_filp; struct inode *inode = file_inode(filp); + int nowait = iocb->ki_flags & IOCB_NOWAIT ? 1 : 0; trace_ocfs2_file_aio_read(inode, filp, filp->f_path.dentry, (unsigned long long)OCFS2_I(inode)->ip_blkno, @@ -2374,9 +2422,14 @@ static ssize_t ocfs2_file_read_iter(stru * need locks to protect pending reads from racing with truncate. */ if (iocb->ki_flags & IOCB_DIRECT) { - ret = ocfs2_rw_lock(inode, 0); + if (nowait) + ret = ocfs2_try_rw_lock(inode, 0); + else + ret = ocfs2_rw_lock(inode, 0); + if (ret < 0) { - mlog_errno(ret); + if (ret != -EAGAIN) + mlog_errno(ret); goto bail; } rw_level = 0; @@ -2393,9 +2446,11 @@ static ssize_t ocfs2_file_read_iter(stru * like i_size. This allows the checks down below * generic_file_aio_read() a chance of actually working. */ - ret = ocfs2_inode_lock_atime(inode, filp->f_path.mnt, &lock_level); + ret = ocfs2_inode_lock_atime(inode, filp->f_path.mnt, &lock_level, + !nowait); if (ret < 0) { - mlog_errno(ret); + if (ret != -EAGAIN) + mlog_errno(ret); goto bail; } ocfs2_inode_unlock(inode, lock_level); diff -puN fs/ocfs2/mmap.c~ocfs2-nowait-aio-support fs/ocfs2/mmap.c --- a/fs/ocfs2/mmap.c~ocfs2-nowait-aio-support +++ a/fs/ocfs2/mmap.c @@ -184,7 +184,7 @@ int ocfs2_mmap(struct file *file, struct int ret = 0, lock_level = 0; ret = ocfs2_inode_lock_atime(file_inode(file), - file->f_path.mnt, &lock_level); + file->f_path.mnt, &lock_level, 1); if (ret < 0) { mlog_errno(ret); goto out; diff -puN fs/ocfs2/ocfs2_trace.h~ocfs2-nowait-aio-support fs/ocfs2/ocfs2_trace.h --- a/fs/ocfs2/ocfs2_trace.h~ocfs2-nowait-aio-support +++ a/fs/ocfs2/ocfs2_trace.h @@ -1449,20 +1449,22 @@ DEFINE_OCFS2_ULL_ULL_ULL_EVENT(ocfs2_rem TRACE_EVENT(ocfs2_prepare_inode_for_write, TP_PROTO(unsigned long long ino, unsigned long long saved_pos, - unsigned long count), - TP_ARGS(ino, saved_pos, count), + unsigned long count, int wait), + TP_ARGS(ino, saved_pos, count, wait), TP_STRUCT__entry( __field(unsigned long long, ino) __field(unsigned long long, saved_pos) __field(unsigned long, count) + __field(int, wait) ), TP_fast_assign( __entry->ino = ino; __entry->saved_pos = saved_pos; __entry->count = count; + __entry->wait = wait; ), - TP_printk("%llu %llu %lu", __entry->ino, - __entry->saved_pos, __entry->count) + TP_printk("%llu %llu %lu %d", __entry->ino, + __entry->saved_pos, __entry->count, __entry->wait) ); DEFINE_OCFS2_INT_EVENT(generic_file_aio_read_ret); _ _______________________________________________ Ocfs2-devel mailing list Ocfs2-devel@oss.oracle.com https://oss.oracle.com/mailman/listinfo/ocfs2-devel
