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(sizeof(*rq), 72 GFP_KERNEL | __GFP_NOFAIL); 73 74 bio_init(&rq->bio, NULL, rq->bvecs, ARRAY_SIZE(rq->bvecs), REQ_OP_READ); 75 rq->iocb.ki_filp = mdev->m_dif->file; 76 rq->sb = mdev->m_sb; 77 refcount_set(&rq->ref, 2); 78 return rq; 79 } 80 81 struct bio *erofs_fileio_bio_alloc(struct erofs_map_dev *mdev) 82 { 83 return &erofs_fileio_rq_alloc(mdev)->bio; 84 } 85 86 void erofs_fileio_submit_bio(struct bio *bio) 87 { 88 return erofs_fileio_rq_submit(container_of(bio, struct erofs_fileio_rq, 89 bio)); 90 } 91 92 static int erofs_fileio_scan_folio(struct erofs_fileio *io, 93 struct inode *inode, struct folio *folio) 94 { 95 struct erofs_map_blocks *map = &io->map; 96 unsigned int cur = 0, end = folio_size(folio), len, attached = 0; 97 loff_t pos = folio_pos(folio), ofs; 98 int err = 0; 99 100 erofs_onlinefolio_init(folio); 101 while (cur < end) { 102 if (!in_range(pos + cur, map->m_la, map->m_llen)) { 103 map->m_la = pos + cur; 104 map->m_llen = end - cur; 105 err = erofs_map_blocks(inode, map); 106 if (err) 107 break; 108 } 109 110 ofs = folio_pos(folio) + cur - map->m_la; 111 len = min_t(loff_t, map->m_llen - ofs, end - cur); 112 if (map->m_flags & EROFS_MAP_META) { 113 struct erofs_buf buf = __EROFS_BUF_INITIALIZER; 114 void *src; 115 116 src = erofs_read_metabuf(&buf, inode->i_sb, 117 map->m_pa + ofs, erofs_inode_in_metabox(inode)); 118 if (IS_ERR(src)) { 119 err = PTR_ERR(src); 120 break; 121 } 122 memcpy_to_folio(folio, cur, src, len); 123 erofs_put_metabuf(&buf); 124 } else if (!(map->m_flags & EROFS_MAP_MAPPED)) { 125 folio_zero_segment(folio, cur, cur + len); 126 attached = 0; 127 } else { 128 if (io->rq && (map->m_pa + ofs != io->dev.m_pa || 129 map->m_deviceid != io->dev.m_deviceid)) { 130 io_retry: 131 erofs_fileio_rq_submit(io->rq); 132 io->rq = NULL; 133 } 134 135 if (!io->rq) { 136 io->dev = (struct erofs_map_dev) { 137 .m_pa = io->map.m_pa + ofs, 138 .m_deviceid = io->map.m_deviceid, 139 }; 140 err = erofs_map_dev(inode->i_sb, &io->dev); 141 if (err) 142 break; 143 io->rq = erofs_fileio_rq_alloc(&io->dev); 144 io->rq->bio.bi_iter.bi_sector = 145 (io->dev.m_dif->fsoff + io->dev.m_pa) >> 9; 146 attached = 0; 147 } 148 if (!bio_add_folio(&io->rq->bio, folio, len, cur)) 149 goto io_retry; 150 if (!attached++) 151 erofs_onlinefolio_split(folio); 152 io->dev.m_pa += len; 153 } 154 cur += len; 155 } 156 erofs_onlinefolio_end(folio, err, false); 157 return err; 158 } 159 160 static int erofs_fileio_read_folio(struct file *file, struct folio *folio) 161 { 162 bool need_iput; 163 struct inode *realinode = erofs_real_inode(folio_inode(folio), &need_iput); 164 struct erofs_fileio io = {}; 165 int err; 166 167 trace_erofs_read_folio(realinode, folio, true); 168 err = erofs_fileio_scan_folio(&io, realinode, folio); 169 erofs_fileio_rq_submit(io.rq); 170 if (need_iput) 171 iput(realinode); 172 return err; 173 } 174 175 static void erofs_fileio_readahead(struct readahead_control *rac) 176 { 177 bool need_iput; 178 struct inode *realinode = erofs_real_inode(rac->mapping->host, &need_iput); 179 struct erofs_fileio io = {}; 180 struct folio *folio; 181 int err; 182 183 trace_erofs_readahead(realinode, readahead_index(rac), 184 readahead_count(rac), true); 185 while ((folio = readahead_folio(rac))) { 186 err = erofs_fileio_scan_folio(&io, realinode, folio); 187 if (err && err != -EINTR) 188 erofs_err(realinode->i_sb, "readahead error at folio %lu @ nid %llu", 189 folio->index, EROFS_I(realinode)->nid); 190 } 191 erofs_fileio_rq_submit(io.rq); 192 if (need_iput) 193 iput(realinode); 194 } 195 196 const struct address_space_operations erofs_fileio_aops = { 197 .read_folio = erofs_fileio_read_folio, 198 .readahead = erofs_fileio_readahead, 199 }; 200