1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (C) 2024, Alibaba Cloud 4 */ 5 #include "internal.h" 6 #include <trace/events/erofs.h> 7 8 struct erofs_fileio_rq { 9 struct bio_vec bvecs[BIO_MAX_VECS]; 10 struct bio bio; 11 struct kiocb iocb; 12 struct super_block *sb; 13 }; 14 15 struct erofs_fileio { 16 struct erofs_map_blocks map; 17 struct erofs_map_dev dev; 18 struct erofs_fileio_rq *rq; 19 }; 20 21 static void erofs_fileio_ki_complete(struct kiocb *iocb, long ret) 22 { 23 struct erofs_fileio_rq *rq = 24 container_of(iocb, struct erofs_fileio_rq, iocb); 25 struct folio_iter fi; 26 27 if (ret > 0) { 28 if (ret != rq->bio.bi_iter.bi_size) { 29 bio_advance(&rq->bio, ret); 30 zero_fill_bio(&rq->bio); 31 } 32 ret = 0; 33 } 34 if (rq->bio.bi_end_io) { 35 rq->bio.bi_end_io(&rq->bio); 36 } else { 37 bio_for_each_folio_all(fi, &rq->bio) { 38 DBG_BUGON(folio_test_uptodate(fi.folio)); 39 erofs_onlinefolio_end(fi.folio, ret); 40 } 41 } 42 bio_uninit(&rq->bio); 43 kfree(rq); 44 } 45 46 static void erofs_fileio_rq_submit(struct erofs_fileio_rq *rq) 47 { 48 struct iov_iter iter; 49 int ret; 50 51 if (!rq) 52 return; 53 rq->iocb.ki_pos = rq->bio.bi_iter.bi_sector << SECTOR_SHIFT; 54 rq->iocb.ki_ioprio = get_current_ioprio(); 55 rq->iocb.ki_complete = erofs_fileio_ki_complete; 56 if (test_opt(&EROFS_SB(rq->sb)->opt, DIRECT_IO) && 57 rq->iocb.ki_filp->f_mode & FMODE_CAN_ODIRECT) 58 rq->iocb.ki_flags = IOCB_DIRECT; 59 iov_iter_bvec(&iter, ITER_DEST, rq->bvecs, rq->bio.bi_vcnt, 60 rq->bio.bi_iter.bi_size); 61 ret = vfs_iocb_iter_read(rq->iocb.ki_filp, &rq->iocb, &iter); 62 if (ret != -EIOCBQUEUED) 63 erofs_fileio_ki_complete(&rq->iocb, ret); 64 } 65 66 static struct erofs_fileio_rq *erofs_fileio_rq_alloc(struct erofs_map_dev *mdev) 67 { 68 struct erofs_fileio_rq *rq = kzalloc(sizeof(*rq), 69 GFP_KERNEL | __GFP_NOFAIL); 70 71 bio_init(&rq->bio, NULL, rq->bvecs, BIO_MAX_VECS, REQ_OP_READ); 72 rq->iocb.ki_filp = mdev->m_dif->file; 73 rq->sb = mdev->m_sb; 74 return rq; 75 } 76 77 struct bio *erofs_fileio_bio_alloc(struct erofs_map_dev *mdev) 78 { 79 return &erofs_fileio_rq_alloc(mdev)->bio; 80 } 81 82 void erofs_fileio_submit_bio(struct bio *bio) 83 { 84 return erofs_fileio_rq_submit(container_of(bio, struct erofs_fileio_rq, 85 bio)); 86 } 87 88 static int erofs_fileio_scan_folio(struct erofs_fileio *io, struct folio *folio) 89 { 90 struct inode *inode = folio_inode(folio); 91 struct erofs_map_blocks *map = &io->map; 92 unsigned int cur = 0, end = folio_size(folio), len, attached = 0; 93 loff_t pos = folio_pos(folio), ofs; 94 struct iov_iter iter; 95 struct bio_vec bv; 96 int err = 0; 97 98 erofs_onlinefolio_init(folio); 99 while (cur < end) { 100 if (!in_range(pos + cur, map->m_la, map->m_llen)) { 101 map->m_la = pos + cur; 102 map->m_llen = end - cur; 103 err = erofs_map_blocks(inode, map); 104 if (err) 105 break; 106 } 107 108 ofs = folio_pos(folio) + cur - map->m_la; 109 len = min_t(loff_t, map->m_llen - ofs, end - cur); 110 if (map->m_flags & EROFS_MAP_META) { 111 struct erofs_buf buf = __EROFS_BUF_INITIALIZER; 112 void *src; 113 114 src = erofs_read_metabuf(&buf, inode->i_sb, 115 map->m_pa + ofs, EROFS_KMAP); 116 if (IS_ERR(src)) { 117 err = PTR_ERR(src); 118 break; 119 } 120 bvec_set_folio(&bv, folio, len, cur); 121 iov_iter_bvec(&iter, ITER_DEST, &bv, 1, len); 122 if (copy_to_iter(src, len, &iter) != len) { 123 erofs_put_metabuf(&buf); 124 err = -EIO; 125 break; 126 } 127 erofs_put_metabuf(&buf); 128 } else if (!(map->m_flags & EROFS_MAP_MAPPED)) { 129 folio_zero_segment(folio, cur, cur + len); 130 attached = 0; 131 } else { 132 if (io->rq && (map->m_pa + ofs != io->dev.m_pa || 133 map->m_deviceid != io->dev.m_deviceid)) { 134 io_retry: 135 erofs_fileio_rq_submit(io->rq); 136 io->rq = NULL; 137 } 138 139 if (!io->rq) { 140 io->dev = (struct erofs_map_dev) { 141 .m_pa = io->map.m_pa + ofs, 142 .m_deviceid = io->map.m_deviceid, 143 }; 144 err = erofs_map_dev(inode->i_sb, &io->dev); 145 if (err) 146 break; 147 io->rq = erofs_fileio_rq_alloc(&io->dev); 148 io->rq->bio.bi_iter.bi_sector = io->dev.m_pa >> 9; 149 attached = 0; 150 } 151 if (!attached++) 152 erofs_onlinefolio_split(folio); 153 if (!bio_add_folio(&io->rq->bio, folio, len, cur)) 154 goto io_retry; 155 io->dev.m_pa += len; 156 } 157 cur += len; 158 } 159 erofs_onlinefolio_end(folio, err); 160 return err; 161 } 162 163 static int erofs_fileio_read_folio(struct file *file, struct folio *folio) 164 { 165 struct erofs_fileio io = {}; 166 int err; 167 168 trace_erofs_read_folio(folio, true); 169 err = erofs_fileio_scan_folio(&io, folio); 170 erofs_fileio_rq_submit(io.rq); 171 return err; 172 } 173 174 static void erofs_fileio_readahead(struct readahead_control *rac) 175 { 176 struct inode *inode = rac->mapping->host; 177 struct erofs_fileio io = {}; 178 struct folio *folio; 179 int err; 180 181 trace_erofs_readpages(inode, readahead_index(rac), 182 readahead_count(rac), true); 183 while ((folio = readahead_folio(rac))) { 184 err = erofs_fileio_scan_folio(&io, folio); 185 if (err && err != -EINTR) 186 erofs_err(inode->i_sb, "readahead error at folio %lu @ nid %llu", 187 folio->index, EROFS_I(inode)->nid); 188 } 189 erofs_fileio_rq_submit(io.rq); 190 } 191 192 const struct address_space_operations erofs_fileio_aops = { 193 .read_folio = erofs_fileio_read_folio, 194 .readahead = erofs_fileio_readahead, 195 }; 196