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[16]; 10 struct bio bio; 11 struct kiocb iocb; 12 struct super_block *sb; 13 refcount_t ref; 14 }; 15 16 struct erofs_fileio { 17 struct erofs_map_blocks map; 18 struct erofs_map_dev dev; 19 struct erofs_fileio_rq *rq; 20 }; 21 22 static void erofs_fileio_ki_complete(struct kiocb *iocb, long ret) 23 { 24 struct erofs_fileio_rq *rq = 25 container_of(iocb, struct erofs_fileio_rq, iocb); 26 struct folio_iter fi; 27 28 if (ret >= 0 && ret != rq->bio.bi_iter.bi_size) { 29 bio_advance(&rq->bio, ret); 30 zero_fill_bio(&rq->bio); 31 } 32 if (!rq->bio.bi_end_io) { 33 bio_for_each_folio_all(fi, &rq->bio) { 34 DBG_BUGON(folio_test_uptodate(fi.folio)); 35 erofs_onlinefolio_end(fi.folio, ret < 0, false); 36 } 37 } else if (ret < 0 && !rq->bio.bi_status) { 38 rq->bio.bi_status = errno_to_blk_status(ret); 39 } 40 bio_endio(&rq->bio); 41 bio_uninit(&rq->bio); 42 if (refcount_dec_and_test(&rq->ref)) 43 kfree(rq); 44 } 45 46 static void erofs_fileio_rq_submit(struct erofs_fileio_rq *rq) 47 { 48 struct iov_iter iter; 49 ssize_t 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 scoped_with_creds(rq->iocb.ki_filp->f_cred) 62 ret = vfs_iocb_iter_read(rq->iocb.ki_filp, &rq->iocb, &iter); 63 if (ret != -EIOCBQUEUED) 64 erofs_fileio_ki_complete(&rq->iocb, ret); 65 if (refcount_dec_and_test(&rq->ref)) 66 kfree(rq); 67 } 68 69 static struct erofs_fileio_rq *erofs_fileio_rq_alloc(struct erofs_map_dev *mdev) 70 { 71 struct erofs_fileio_rq *rq = kzalloc_obj(*rq, GFP_KERNEL | __GFP_NOFAIL); 72 73 bio_init(&rq->bio, NULL, rq->bvecs, ARRAY_SIZE(rq->bvecs), REQ_OP_READ); 74 rq->iocb.ki_filp = mdev->m_dif->file; 75 rq->sb = mdev->m_sb; 76 refcount_set(&rq->ref, 2); 77 return rq; 78 } 79 80 struct bio *erofs_fileio_bio_alloc(struct erofs_map_dev *mdev) 81 { 82 return &erofs_fileio_rq_alloc(mdev)->bio; 83 } 84 85 void erofs_fileio_submit_bio(struct bio *bio) 86 { 87 return erofs_fileio_rq_submit(container_of(bio, struct erofs_fileio_rq, 88 bio)); 89 } 90 91 static int erofs_fileio_scan_folio(struct erofs_fileio *io, 92 struct inode *inode, struct folio *folio) 93 { 94 struct erofs_map_blocks *map = &io->map; 95 unsigned int cur = 0, end = folio_size(folio), len, attached = 0; 96 loff_t pos = folio_pos(folio), ofs; 97 int err = 0; 98 99 erofs_onlinefolio_init(folio); 100 while (cur < end) { 101 if (!in_range(pos + cur, map->m_la, map->m_llen)) { 102 map->m_la = pos + cur; 103 map->m_llen = end - cur; 104 err = erofs_map_blocks(inode, map); 105 if (err) 106 break; 107 } 108 109 ofs = folio_pos(folio) + cur - map->m_la; 110 len = min_t(loff_t, map->m_llen - ofs, end - cur); 111 if (map->m_flags & EROFS_MAP_META) { 112 struct erofs_buf buf = __EROFS_BUF_INITIALIZER; 113 void *src; 114 115 src = erofs_read_metabuf(&buf, inode->i_sb, 116 map->m_pa + ofs, erofs_inode_in_metabox(inode)); 117 if (IS_ERR(src)) { 118 err = PTR_ERR(src); 119 break; 120 } 121 memcpy_to_folio(folio, cur, src, len); 122 erofs_put_metabuf(&buf); 123 } else if (!(map->m_flags & EROFS_MAP_MAPPED)) { 124 folio_zero_segment(folio, cur, cur + len); 125 attached = 0; 126 } else { 127 if (io->rq && (map->m_pa + ofs != io->dev.m_pa || 128 map->m_deviceid != io->dev.m_deviceid)) { 129 io_retry: 130 erofs_fileio_rq_submit(io->rq); 131 io->rq = NULL; 132 } 133 134 if (!io->rq) { 135 io->dev = (struct erofs_map_dev) { 136 .m_pa = io->map.m_pa + ofs, 137 .m_deviceid = io->map.m_deviceid, 138 }; 139 err = erofs_map_dev(inode->i_sb, &io->dev); 140 if (err) 141 break; 142 io->rq = erofs_fileio_rq_alloc(&io->dev); 143 io->rq->bio.bi_iter.bi_sector = 144 (io->dev.m_dif->fsoff + io->dev.m_pa) >> 9; 145 attached = 0; 146 } 147 if (!bio_add_folio(&io->rq->bio, folio, len, cur)) 148 goto io_retry; 149 if (!attached++) 150 erofs_onlinefolio_split(folio); 151 io->dev.m_pa += len; 152 } 153 cur += len; 154 } 155 erofs_onlinefolio_end(folio, err, false); 156 return err; 157 } 158 159 static int erofs_fileio_read_folio(struct file *file, struct folio *folio) 160 { 161 bool need_iput; 162 struct inode *realinode = erofs_real_inode(folio_inode(folio), &need_iput); 163 struct erofs_fileio io = {}; 164 int err; 165 166 trace_erofs_read_folio(realinode, folio, true); 167 err = erofs_fileio_scan_folio(&io, realinode, folio); 168 erofs_fileio_rq_submit(io.rq); 169 if (need_iput) 170 iput(realinode); 171 return err; 172 } 173 174 static void erofs_fileio_readahead(struct readahead_control *rac) 175 { 176 bool need_iput; 177 struct inode *realinode = erofs_real_inode(rac->mapping->host, &need_iput); 178 struct erofs_fileio io = {}; 179 struct folio *folio; 180 int err; 181 182 trace_erofs_readahead(realinode, readahead_index(rac), 183 readahead_count(rac), true); 184 while ((folio = readahead_folio(rac))) { 185 err = erofs_fileio_scan_folio(&io, realinode, folio); 186 if (err && err != -EINTR) 187 erofs_err(realinode->i_sb, "readahead error at folio %lu @ nid %llu", 188 folio->index, EROFS_I(realinode)->nid); 189 } 190 erofs_fileio_rq_submit(io.rq); 191 if (need_iput) 192 iput(realinode); 193 } 194 195 const struct address_space_operations erofs_fileio_aops = { 196 .read_folio = erofs_fileio_read_folio, 197 .readahead = erofs_fileio_readahead, 198 }; 199