>On 09/24/2013 04:05 PM, majianpeng wrote: >> diff --git a/fs/ceph/file.c b/fs/ceph/file.c >> index 3de8982..5422d8e 100644 >> --- a/fs/ceph/file.c >> +++ b/fs/ceph/file.c >> @@ -408,51 +408,94 @@ more: >> * >> * If the read spans object boundary, just do multiple reads. >> */ >> -static ssize_t ceph_sync_read(struct file *file, char __user *data, >> - unsigned len, loff_t *poff, int *checkeof) >> +static ssize_t ceph_sync_read(struct kiocb *iocb, struct iov_iter *i, >> + int *checkeof) >> { >> + struct file *file = iocb->ki_filp; >> struct inode *inode = file_inode(file); >> struct page **pages; >> - u64 off = *poff; >> + u64 off = iocb->ki_pos; >> int num_pages, ret; >> >> - dout("sync_read on file %p %llu~%u %s\n", file, off, len, >> + dout("sync_read on file %p %llu~%u %s\n", file, off, >> + (unsigned)iocb->ki_left, >> (file->f_flags & O_DIRECT) ? "O_DIRECT" : ""); >> - >> - if (file->f_flags & O_DIRECT) { >> - num_pages = calc_pages_for((unsigned long)data, len); >> - pages = ceph_get_direct_page_vector(data, num_pages, true); >> - } else { >> - num_pages = calc_pages_for(off, len); >> - pages = ceph_alloc_page_vector(num_pages, GFP_NOFS); >> - } >> - if (IS_ERR(pages)) >> - return PTR_ERR(pages); >> - >> /* >> * flush any page cache pages in this range. this >> * will make concurrent normal and sync io slow, >> * but it will at least behave sensibly when they are >> * in sequence. >> */ >> - ret = filemap_write_and_wait(inode->i_mapping); >> + ret = filemap_write_and_wait_range(inode->i_mapping, off, >> + off + iocb->ki_left); >> if (ret < 0) >> - goto done; >> - >> - ret = striped_read(inode, off, len, pages, num_pages, checkeof, >> - file->f_flags & O_DIRECT, >> - (unsigned long)data & ~PAGE_MASK); >> + return ret; >> >> - if (ret >= 0 && (file->f_flags & O_DIRECT) == 0) >> - ret = ceph_copy_page_vector_to_user(pages, data, off, ret); >> - if (ret >= 0) >> - *poff = off + ret; >> + if (file->f_flags & O_DIRECT) { >> + while (iov_iter_count(i)) { >> + void __user *data = i->iov[0].iov_base + i->iov_offset; >> + size_t len = i->iov[0].iov_len - i->iov_offset; >> + >> + num_pages = calc_pages_for((unsigned long)data, len); >> + pages = ceph_get_direct_page_vector(data, >> + num_pages, true); >> + if (IS_ERR(pages)) >> + return PTR_ERR(pages); >> + >> + ret = striped_read(inode, off, len, >> + pages, num_pages, checkeof, >> + 1, (unsigned long)data & ~PAGE_MASK); >> + ceph_put_page_vector(pages, num_pages, true); >> + >> + if (ret <= 0) >> + break; >> + off += ret; >> + iov_iter_advance(i, ret); >> + if (ret < len) >> + break; >> + } >> + } else { >> + size_t len = iocb->ki_left; >> >> -done: >> - if (file->f_flags & O_DIRECT) >> - ceph_put_page_vector(pages, num_pages, true); >> - else >> + num_pages = calc_pages_for(off, len); >> + pages = ceph_alloc_page_vector(num_pages, GFP_NOFS); >> + if (IS_ERR(pages)) >> + return PTR_ERR(pages); >> + ret = striped_read(inode, off, len, pages, >> + num_pages, checkeof, 0, 0); >> + if (ret > 0) { >> + int l, k = 0; >> + size_t left = len = ret; >> + >> + while (left) { >> + void __user *data = i->iov[0].iov_base >> + + i->iov_offset; >> + l = min(i->iov[0].iov_len - i->iov_offset, >> + left); >> + >> + ret = ceph_copy_page_vector_to_user(&pages[k], >> + data, off, >> + l); >> + if (ret > 0) { >> + iov_iter_advance(i, ret); >> + left -= ret; >> + off += ret; >> + k = calc_pages_for(iocb->ki_pos, >> + len - left + 1) - 1; >> + BUG_ON(k >= num_pages && left); >> + } else >> + break; >> + } >> + } >> ceph_release_page_vector(pages, num_pages); >> + } >> + >> + if (off > iocb->ki_pos) { >> + ret = off - iocb->ki_pos; >> + iocb->ki_pos = off; >> + iocb->ki_left -= ret; >> + } >> + >> dout("sync_read result %d\n", ret); >> return ret; >> } >> @@ -647,17 +690,16 @@ static ssize_t ceph_aio_read(struct kiocb *iocb, const struct iovec *iov, >> { >> struct file *filp = iocb->ki_filp; >> struct ceph_file_info *fi = filp->private_data; >> - loff_t *ppos = &iocb->ki_pos; >> - size_t len = iov->iov_len; >> + size_t len = 0; > >len = iocb->ki_left; Yes, the dout need this. > >> struct inode *inode = file_inode(filp); >> struct ceph_inode_info *ci = ceph_inode(inode); >> - void __user *base = iov->iov_base; >> ssize_t ret; >> int want, got = 0; >> int checkeof = 0, read = 0; >> > >I think we should put label 'again' here. Ok > >> dout("aio_read %p %llx.%llx %llu~%u trying to get caps on %p\n", >> inode, ceph_vinop(inode), pos, (unsigned)len, inode); >> + >> again: >> if (fi->fmode & CEPH_FILE_MODE_LAZY) >> want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO; >> @@ -665,38 +707,61 @@ again: >> want = CEPH_CAP_FILE_CACHE; >> ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want, &got, -1); >> if (ret < 0) >> - goto out; >> + return ret; >> + >> dout("aio_read %p %llx.%llx %llu~%u got cap refs on %s\n", >> inode, ceph_vinop(inode), pos, (unsigned)len, >> ceph_cap_string(got)); >> >> if ((got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0 || >> (iocb->ki_filp->f_flags & O_DIRECT) || >> - (fi->flags & CEPH_F_SYNC)) >> + (fi->flags & CEPH_F_SYNC)) { >> + struct iov_iter i; >> + >> + if (!read) { >> + ret = generic_segment_checks(iov, &nr_segs, >> + &len, VERIFY_WRITE); >> + if (ret) >> + goto out; >> + } >> + >> + iocb->ki_left = len; > >iocb->ki_left = len - read ? Before goto again, i let 'len -= ret'. len mean the left size. > > >> + iov_iter_init(&i, iov, nr_segs, len, read); >> /* hmm, this isn't really async... */ >> - ret = ceph_sync_read(filp, base, len, ppos, &checkeof); >> - else >> + ret = ceph_sync_read(iocb, &i, &checkeof); >> + } else { >> + /* >> + * We can't modify the content of iov, >> + * so we only read from beginning. >> + */ >> + if (read) >> + iocb->ki_pos = pos; > >forget to set 'read' to 0 ? When define read, i set read = 0. >int checkeof = 0, read = 0; > > >> ret = generic_file_aio_read(iocb, iov, nr_segs, pos); >> - >> + } >> out: >> dout("aio_read %p %llx.%llx dropping cap refs on %s = %d\n", >> inode, ceph_vinop(inode), ceph_cap_string(got), (int)ret); >> ceph_put_cap_refs(ci, got); >> >> if (checkeof && ret >= 0) { >> - int statret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE); >> + int statret = ceph_do_getattr(inode, >> + CEPH_STAT_CAP_SIZE); >> >> /* hit EOF or hole? */ >> - if (statret == 0 && *ppos < inode->i_size) { >> - dout("aio_read sync_read hit hole, ppos %lld < size %lld, reading more\n", *ppos, inode->i_size); >> + if (statret == 0 && iocb->ki_pos < inode->i_size && >> + iocb->ki_left) { >> + dout("sync_read hit hole, ppos %lld < size %lld" >> + ", reading more\n", iocb->ki_pos, >> + inode->i_size); >> + >> read += ret; >> - base += ret; >> len -= ret; >> checkeof = 0; >> goto again; >> } >> } >> - if (ret >= 0) >> + >> + if (ret > 0) >> ret += read; > >what is the purpose of this change ? Sorry, i make a mistake. > >Regards >Yan, Zheng >> >> return ret; >> -- >ÿôèº{.nÇ+?·?®??+%?Ëÿ±éݶ¥?wÿº{.nÇ+?·?z?ÿuëÞ?ø§¶?¡Ü¨}©?²Æ zÚ&j:+v?¨þø¯ù®w¥þ?à2?Þ?¨èÚ&¢)ß¡«a¶Úÿÿûàz¿äz¹Þ?ú+?ù???Ý¢jÿ?wèþf