| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * linux/drivers/staging/erofs/unzip_vle.c |
| * |
| * Copyright (C) 2018 HUAWEI, Inc. |
| * http://www.huawei.com/ |
| * Created by Gao Xiang <gaoxiang25@huawei.com> |
| * |
| * This file is subject to the terms and conditions of the GNU General Public |
| * License. See the file COPYING in the main directory of the Linux |
| * distribution for more details. |
| */ |
| #include "unzip_vle.h" |
| #include <linux/prefetch.h> |
| |
| static struct workqueue_struct *z_erofs_workqueue __read_mostly; |
| static struct kmem_cache *z_erofs_workgroup_cachep __read_mostly; |
| |
| void z_erofs_exit_zip_subsystem(void) |
| { |
| BUG_ON(z_erofs_workqueue == NULL); |
| BUG_ON(z_erofs_workgroup_cachep == NULL); |
| |
| destroy_workqueue(z_erofs_workqueue); |
| kmem_cache_destroy(z_erofs_workgroup_cachep); |
| } |
| |
| static inline int init_unzip_workqueue(void) |
| { |
| const unsigned onlinecpus = num_possible_cpus(); |
| |
| /* |
| * we don't need too many threads, limiting threads |
| * could improve scheduling performance. |
| */ |
| z_erofs_workqueue = alloc_workqueue("erofs_unzipd", |
| WQ_UNBOUND | WQ_HIGHPRI | WQ_CPU_INTENSIVE, |
| onlinecpus + onlinecpus / 4); |
| |
| return z_erofs_workqueue != NULL ? 0 : -ENOMEM; |
| } |
| |
| int z_erofs_init_zip_subsystem(void) |
| { |
| z_erofs_workgroup_cachep = |
| kmem_cache_create("erofs_compress", |
| Z_EROFS_WORKGROUP_SIZE, 0, |
| SLAB_RECLAIM_ACCOUNT, NULL); |
| |
| if (z_erofs_workgroup_cachep != NULL) { |
| if (!init_unzip_workqueue()) |
| return 0; |
| |
| kmem_cache_destroy(z_erofs_workgroup_cachep); |
| } |
| return -ENOMEM; |
| } |
| |
| enum z_erofs_vle_work_role { |
| Z_EROFS_VLE_WORK_SECONDARY, |
| Z_EROFS_VLE_WORK_PRIMARY, |
| /* |
| * The current work has at least been linked with the following |
| * processed chained works, which means if the processing page |
| * is the tail partial page of the work, the current work can |
| * safely use the whole page, as illustrated below: |
| * +--------------+-------------------------------------------+ |
| * | tail page | head page (of the previous work) | |
| * +--------------+-------------------------------------------+ |
| * /\ which belongs to the current work |
| * [ (*) this page can be used for the current work itself. ] |
| */ |
| Z_EROFS_VLE_WORK_PRIMARY_FOLLOWED, |
| Z_EROFS_VLE_WORK_MAX |
| }; |
| |
| struct z_erofs_vle_work_builder { |
| enum z_erofs_vle_work_role role; |
| /* |
| * 'hosted = false' means that the current workgroup doesn't belong to |
| * the owned chained workgroups. In the other words, it is none of our |
| * business to submit this workgroup. |
| */ |
| bool hosted; |
| |
| struct z_erofs_vle_workgroup *grp; |
| struct z_erofs_vle_work *work; |
| struct z_erofs_pagevec_ctor vector; |
| |
| /* pages used for reading the compressed data */ |
| struct page **compressed_pages; |
| unsigned compressed_deficit; |
| }; |
| |
| #define VLE_WORK_BUILDER_INIT() \ |
| { .work = NULL, .role = Z_EROFS_VLE_WORK_PRIMARY_FOLLOWED } |
| |
| #ifdef EROFS_FS_HAS_MANAGED_CACHE |
| |
| static bool grab_managed_cache_pages(struct address_space *mapping, |
| erofs_blk_t start, |
| struct page **compressed_pages, |
| int clusterblks, |
| bool reserve_allocation) |
| { |
| bool noio = true; |
| unsigned int i; |
| |
| /* TODO: optimize by introducing find_get_pages_range */ |
| for (i = 0; i < clusterblks; ++i) { |
| struct page *page, *found; |
| |
| if (READ_ONCE(compressed_pages[i]) != NULL) |
| continue; |
| |
| page = found = find_get_page(mapping, start + i); |
| if (found == NULL) { |
| noio = false; |
| if (!reserve_allocation) |
| continue; |
| page = EROFS_UNALLOCATED_CACHED_PAGE; |
| } |
| |
| if (NULL == cmpxchg(compressed_pages + i, NULL, page)) |
| continue; |
| |
| if (found != NULL) |
| put_page(found); |
| } |
| return noio; |
| } |
| |
| /* called by erofs_shrinker to get rid of all compressed_pages */ |
| int erofs_try_to_free_all_cached_pages(struct erofs_sb_info *sbi, |
| struct erofs_workgroup *egrp) |
| { |
| struct z_erofs_vle_workgroup *const grp = |
| container_of(egrp, struct z_erofs_vle_workgroup, obj); |
| struct address_space *const mapping = sbi->managed_cache->i_mapping; |
| const int clusterpages = erofs_clusterpages(sbi); |
| int i; |
| |
| /* |
| * refcount of workgroup is now freezed as 1, |
| * therefore no need to worry about available decompression users. |
| */ |
| for (i = 0; i < clusterpages; ++i) { |
| struct page *page = grp->compressed_pages[i]; |
| |
| if (page == NULL || page->mapping != mapping) |
| continue; |
| |
| /* block other users from reclaiming or migrating the page */ |
| if (!trylock_page(page)) |
| return -EBUSY; |
| |
| /* barrier is implied in the following 'unlock_page' */ |
| WRITE_ONCE(grp->compressed_pages[i], NULL); |
| |
| set_page_private(page, 0); |
| ClearPagePrivate(page); |
| |
| unlock_page(page); |
| put_page(page); |
| } |
| return 0; |
| } |
| |
| int erofs_try_to_free_cached_page(struct address_space *mapping, |
| struct page *page) |
| { |
| struct erofs_sb_info *const sbi = EROFS_SB(mapping->host->i_sb); |
| const unsigned int clusterpages = erofs_clusterpages(sbi); |
| |
| struct z_erofs_vle_workgroup *grp; |
| int ret = 0; /* 0 - busy */ |
| |
| /* prevent the workgroup from being freed */ |
| rcu_read_lock(); |
| grp = (void *)page_private(page); |
| |
| if (erofs_workgroup_try_to_freeze(&grp->obj, 1)) { |
| unsigned int i; |
| |
| for (i = 0; i < clusterpages; ++i) { |
| if (grp->compressed_pages[i] == page) { |
| WRITE_ONCE(grp->compressed_pages[i], NULL); |
| ret = 1; |
| break; |
| } |
| } |
| erofs_workgroup_unfreeze(&grp->obj, 1); |
| } |
| rcu_read_unlock(); |
| |
| if (ret) { |
| ClearPagePrivate(page); |
| put_page(page); |
| } |
| return ret; |
| } |
| #endif |
| |
| /* page_type must be Z_EROFS_PAGE_TYPE_EXCLUSIVE */ |
| static inline bool try_to_reuse_as_compressed_page( |
| struct z_erofs_vle_work_builder *b, |
| struct page *page) |
| { |
| while (b->compressed_deficit) { |
| --b->compressed_deficit; |
| if (NULL == cmpxchg(b->compressed_pages++, NULL, page)) |
| return true; |
| } |
| |
| return false; |
| } |
| |
| /* callers must be with work->lock held */ |
| static int z_erofs_vle_work_add_page( |
| struct z_erofs_vle_work_builder *builder, |
| struct page *page, |
| enum z_erofs_page_type type) |
| { |
| int ret; |
| bool occupied; |
| |
| /* give priority for the compressed data storage */ |
| if (builder->role >= Z_EROFS_VLE_WORK_PRIMARY && |
| type == Z_EROFS_PAGE_TYPE_EXCLUSIVE && |
| try_to_reuse_as_compressed_page(builder, page)) |
| return 0; |
| |
| ret = z_erofs_pagevec_ctor_enqueue(&builder->vector, |
| page, type, &occupied); |
| builder->work->vcnt += (unsigned)ret; |
| |
| return ret ? 0 : -EAGAIN; |
| } |
| |
| static inline bool try_to_claim_workgroup( |
| struct z_erofs_vle_workgroup *grp, |
| z_erofs_vle_owned_workgrp_t *owned_head, |
| bool *hosted) |
| { |
| DBG_BUGON(*hosted == true); |
| |
| /* let's claim these following types of workgroup */ |
| retry: |
| if (grp->next == Z_EROFS_VLE_WORKGRP_NIL) { |
| /* type 1, nil workgroup */ |
| if (Z_EROFS_VLE_WORKGRP_NIL != cmpxchg(&grp->next, |
| Z_EROFS_VLE_WORKGRP_NIL, *owned_head)) |
| goto retry; |
| |
| *owned_head = grp; |
| *hosted = true; |
| } else if (grp->next == Z_EROFS_VLE_WORKGRP_TAIL) { |
| /* |
| * type 2, link to the end of a existing open chain, |
| * be careful that its submission itself is governed |
| * by the original owned chain. |
| */ |
| if (Z_EROFS_VLE_WORKGRP_TAIL != cmpxchg(&grp->next, |
| Z_EROFS_VLE_WORKGRP_TAIL, *owned_head)) |
| goto retry; |
| |
| *owned_head = Z_EROFS_VLE_WORKGRP_TAIL; |
| } else |
| return false; /* :( better luck next time */ |
| |
| return true; /* lucky, I am the followee :) */ |
| } |
| |
| static struct z_erofs_vle_work * |
| z_erofs_vle_work_lookup(struct super_block *sb, |
| pgoff_t idx, unsigned pageofs, |
| struct z_erofs_vle_workgroup **grp_ret, |
| enum z_erofs_vle_work_role *role, |
| z_erofs_vle_owned_workgrp_t *owned_head, |
| bool *hosted) |
| { |
| bool tag, primary; |
| struct erofs_workgroup *egrp; |
| struct z_erofs_vle_workgroup *grp; |
| struct z_erofs_vle_work *work; |
| |
| egrp = erofs_find_workgroup(sb, idx, &tag); |
| if (egrp == NULL) { |
| *grp_ret = NULL; |
| return NULL; |
| } |
| |
| *grp_ret = grp = container_of(egrp, |
| struct z_erofs_vle_workgroup, obj); |
| |
| #ifndef CONFIG_EROFS_FS_ZIP_MULTIREF |
| work = z_erofs_vle_grab_work(grp, pageofs); |
| primary = true; |
| #else |
| BUG(); |
| #endif |
| |
| DBG_BUGON(work->pageofs != pageofs); |
| |
| /* |
| * lock must be taken first to avoid grp->next == NIL between |
| * claiming workgroup and adding pages: |
| * grp->next != NIL |
| * grp->next = NIL |
| * mutex_unlock_all |
| * mutex_lock(&work->lock) |
| * add all pages to pagevec |
| * |
| * [correct locking case 1]: |
| * mutex_lock(grp->work[a]) |
| * ... |
| * mutex_lock(grp->work[b]) mutex_lock(grp->work[c]) |
| * ... *role = SECONDARY |
| * add all pages to pagevec |
| * ... |
| * mutex_unlock(grp->work[c]) |
| * mutex_lock(grp->work[c]) |
| * ... |
| * grp->next = NIL |
| * mutex_unlock_all |
| * |
| * [correct locking case 2]: |
| * mutex_lock(grp->work[b]) |
| * ... |
| * mutex_lock(grp->work[a]) |
| * ... |
| * mutex_lock(grp->work[c]) |
| * ... |
| * grp->next = NIL |
| * mutex_unlock_all |
| * mutex_lock(grp->work[a]) |
| * *role = PRIMARY_OWNER |
| * add all pages to pagevec |
| * ... |
| */ |
| mutex_lock(&work->lock); |
| |
| *hosted = false; |
| if (!primary) |
| *role = Z_EROFS_VLE_WORK_SECONDARY; |
| /* claim the workgroup if possible */ |
| else if (try_to_claim_workgroup(grp, owned_head, hosted)) |
| *role = Z_EROFS_VLE_WORK_PRIMARY_FOLLOWED; |
| else |
| *role = Z_EROFS_VLE_WORK_PRIMARY; |
| |
| return work; |
| } |
| |
| static struct z_erofs_vle_work * |
| z_erofs_vle_work_register(struct super_block *sb, |
| struct z_erofs_vle_workgroup **grp_ret, |
| struct erofs_map_blocks *map, |
| pgoff_t index, unsigned pageofs, |
| enum z_erofs_vle_work_role *role, |
| z_erofs_vle_owned_workgrp_t *owned_head, |
| bool *hosted) |
| { |
| bool newgrp = false; |
| struct z_erofs_vle_workgroup *grp = *grp_ret; |
| struct z_erofs_vle_work *work; |
| |
| #ifndef CONFIG_EROFS_FS_ZIP_MULTIREF |
| BUG_ON(grp != NULL); |
| #else |
| if (grp != NULL) |
| goto skip; |
| #endif |
| /* no available workgroup, let's allocate one */ |
| grp = kmem_cache_zalloc(z_erofs_workgroup_cachep, GFP_NOFS); |
| if (unlikely(grp == NULL)) |
| return ERR_PTR(-ENOMEM); |
| |
| grp->obj.index = index; |
| grp->llen = map->m_llen; |
| |
| z_erofs_vle_set_workgrp_fmt(grp, |
| (map->m_flags & EROFS_MAP_ZIPPED) ? |
| Z_EROFS_VLE_WORKGRP_FMT_LZ4 : |
| Z_EROFS_VLE_WORKGRP_FMT_PLAIN); |
| atomic_set(&grp->obj.refcount, 1); |
| |
| /* new workgrps have been claimed as type 1 */ |
| WRITE_ONCE(grp->next, *owned_head); |
| /* primary and followed work for all new workgrps */ |
| *role = Z_EROFS_VLE_WORK_PRIMARY_FOLLOWED; |
| /* it should be submitted by ourselves */ |
| *hosted = true; |
| |
| newgrp = true; |
| #ifdef CONFIG_EROFS_FS_ZIP_MULTIREF |
| skip: |
| /* currently unimplemented */ |
| BUG(); |
| #else |
| work = z_erofs_vle_grab_primary_work(grp); |
| #endif |
| work->pageofs = pageofs; |
| |
| mutex_init(&work->lock); |
| |
| if (newgrp) { |
| int err = erofs_register_workgroup(sb, &grp->obj, 0); |
| |
| if (err) { |
| kmem_cache_free(z_erofs_workgroup_cachep, grp); |
| return ERR_PTR(-EAGAIN); |
| } |
| } |
| |
| *owned_head = *grp_ret = grp; |
| |
| mutex_lock(&work->lock); |
| return work; |
| } |
| |
| static inline void __update_workgrp_llen(struct z_erofs_vle_workgroup *grp, |
| unsigned int llen) |
| { |
| while (1) { |
| unsigned int orig_llen = grp->llen; |
| |
| if (orig_llen >= llen || orig_llen == |
| cmpxchg(&grp->llen, orig_llen, llen)) |
| break; |
| } |
| } |
| |
| #define builder_is_followed(builder) \ |
| ((builder)->role >= Z_EROFS_VLE_WORK_PRIMARY_FOLLOWED) |
| |
| static int z_erofs_vle_work_iter_begin(struct z_erofs_vle_work_builder *builder, |
| struct super_block *sb, |
| struct erofs_map_blocks *map, |
| z_erofs_vle_owned_workgrp_t *owned_head) |
| { |
| const unsigned clusterpages = erofs_clusterpages(EROFS_SB(sb)); |
| const erofs_blk_t index = erofs_blknr(map->m_pa); |
| const unsigned pageofs = map->m_la & ~PAGE_MASK; |
| struct z_erofs_vle_workgroup *grp; |
| struct z_erofs_vle_work *work; |
| |
| DBG_BUGON(builder->work != NULL); |
| |
| /* must be Z_EROFS_WORK_TAIL or the next chained work */ |
| DBG_BUGON(*owned_head == Z_EROFS_VLE_WORKGRP_NIL); |
| DBG_BUGON(*owned_head == Z_EROFS_VLE_WORKGRP_TAIL_CLOSED); |
| |
| DBG_BUGON(erofs_blkoff(map->m_pa)); |
| |
| repeat: |
| work = z_erofs_vle_work_lookup(sb, index, |
| pageofs, &grp, &builder->role, owned_head, &builder->hosted); |
| if (work != NULL) { |
| __update_workgrp_llen(grp, map->m_llen); |
| goto got_it; |
| } |
| |
| work = z_erofs_vle_work_register(sb, &grp, map, index, pageofs, |
| &builder->role, owned_head, &builder->hosted); |
| |
| if (unlikely(work == ERR_PTR(-EAGAIN))) |
| goto repeat; |
| |
| if (unlikely(IS_ERR(work))) |
| return PTR_ERR(work); |
| got_it: |
| z_erofs_pagevec_ctor_init(&builder->vector, |
| Z_EROFS_VLE_INLINE_PAGEVECS, work->pagevec, work->vcnt); |
| |
| if (builder->role >= Z_EROFS_VLE_WORK_PRIMARY) { |
| /* enable possibly in-place decompression */ |
| builder->compressed_pages = grp->compressed_pages; |
| builder->compressed_deficit = clusterpages; |
| } else { |
| builder->compressed_pages = NULL; |
| builder->compressed_deficit = 0; |
| } |
| |
| builder->grp = grp; |
| builder->work = work; |
| return 0; |
| } |
| |
| /* |
| * keep in mind that no referenced workgroups will be freed |
| * only after a RCU grace period, so rcu_read_lock() could |
| * prevent a workgroup from being freed. |
| */ |
| static void z_erofs_rcu_callback(struct rcu_head *head) |
| { |
| struct z_erofs_vle_work *work = container_of(head, |
| struct z_erofs_vle_work, rcu); |
| struct z_erofs_vle_workgroup *grp = |
| z_erofs_vle_work_workgroup(work, true); |
| |
| kmem_cache_free(z_erofs_workgroup_cachep, grp); |
| } |
| |
| void erofs_workgroup_free_rcu(struct erofs_workgroup *grp) |
| { |
| struct z_erofs_vle_workgroup *const vgrp = container_of(grp, |
| struct z_erofs_vle_workgroup, obj); |
| struct z_erofs_vle_work *const work = &vgrp->work; |
| |
| call_rcu(&work->rcu, z_erofs_rcu_callback); |
| } |
| |
| static void __z_erofs_vle_work_release(struct z_erofs_vle_workgroup *grp, |
| struct z_erofs_vle_work *work __maybe_unused) |
| { |
| erofs_workgroup_put(&grp->obj); |
| } |
| |
| void z_erofs_vle_work_release(struct z_erofs_vle_work *work) |
| { |
| struct z_erofs_vle_workgroup *grp = |
| z_erofs_vle_work_workgroup(work, true); |
| |
| __z_erofs_vle_work_release(grp, work); |
| } |
| |
| static inline bool |
| z_erofs_vle_work_iter_end(struct z_erofs_vle_work_builder *builder) |
| { |
| struct z_erofs_vle_work *work = builder->work; |
| |
| if (work == NULL) |
| return false; |
| |
| z_erofs_pagevec_ctor_exit(&builder->vector, false); |
| mutex_unlock(&work->lock); |
| |
| /* |
| * if all pending pages are added, don't hold work reference |
| * any longer if the current work isn't hosted by ourselves. |
| */ |
| if (!builder->hosted) |
| __z_erofs_vle_work_release(builder->grp, work); |
| |
| builder->work = NULL; |
| builder->grp = NULL; |
| return true; |
| } |
| |
| static inline struct page *__stagingpage_alloc(struct list_head *pagepool, |
| gfp_t gfp) |
| { |
| struct page *page = erofs_allocpage(pagepool, gfp); |
| |
| if (unlikely(page == NULL)) |
| return NULL; |
| |
| page->mapping = Z_EROFS_MAPPING_STAGING; |
| return page; |
| } |
| |
| struct z_erofs_vle_frontend { |
| struct inode *const inode; |
| |
| struct z_erofs_vle_work_builder builder; |
| struct erofs_map_blocks_iter m_iter; |
| |
| z_erofs_vle_owned_workgrp_t owned_head; |
| |
| bool initial; |
| #if (EROFS_FS_ZIP_CACHE_LVL >= 2) |
| erofs_off_t cachedzone_la; |
| #endif |
| }; |
| |
| #define VLE_FRONTEND_INIT(__i) { \ |
| .inode = __i, \ |
| .m_iter = { \ |
| { .m_llen = 0, .m_plen = 0 }, \ |
| .mpage = NULL \ |
| }, \ |
| .builder = VLE_WORK_BUILDER_INIT(), \ |
| .owned_head = Z_EROFS_VLE_WORKGRP_TAIL, \ |
| .initial = true, } |
| |
| static int z_erofs_do_read_page(struct z_erofs_vle_frontend *fe, |
| struct page *page, |
| struct list_head *page_pool) |
| { |
| struct super_block *const sb = fe->inode->i_sb; |
| struct erofs_sb_info *const sbi __maybe_unused = EROFS_SB(sb); |
| struct erofs_map_blocks_iter *const m = &fe->m_iter; |
| struct erofs_map_blocks *const map = &m->map; |
| struct z_erofs_vle_work_builder *const builder = &fe->builder; |
| const loff_t offset = page_offset(page); |
| |
| bool tight = builder_is_followed(builder); |
| struct z_erofs_vle_work *work = builder->work; |
| |
| #ifdef EROFS_FS_HAS_MANAGED_CACHE |
| struct address_space *const mngda = sbi->managed_cache->i_mapping; |
| struct z_erofs_vle_workgroup *grp; |
| bool noio_outoforder; |
| #endif |
| |
| enum z_erofs_page_type page_type; |
| unsigned cur, end, spiltted, index; |
| int err; |
| |
| /* register locked file pages as online pages in pack */ |
| z_erofs_onlinepage_init(page); |
| |
| spiltted = 0; |
| end = PAGE_SIZE; |
| repeat: |
| cur = end - 1; |
| |
| /* lucky, within the range of the current map_blocks */ |
| if (offset + cur >= map->m_la && |
| offset + cur < map->m_la + map->m_llen) |
| goto hitted; |
| |
| /* go ahead the next map_blocks */ |
| debugln("%s: [out-of-range] pos %llu", __func__, offset + cur); |
| |
| if (!z_erofs_vle_work_iter_end(builder)) |
| fe->initial = false; |
| |
| map->m_la = offset + cur; |
| map->m_llen = 0; |
| err = erofs_map_blocks_iter(fe->inode, map, &m->mpage, 0); |
| if (unlikely(err)) |
| goto err_out; |
| |
| /* deal with hole (FIXME! broken now) */ |
| if (unlikely(!(map->m_flags & EROFS_MAP_MAPPED))) |
| goto hitted; |
| |
| DBG_BUGON(map->m_plen != 1 << sbi->clusterbits); |
| BUG_ON(erofs_blkoff(map->m_pa)); |
| |
| err = z_erofs_vle_work_iter_begin(builder, sb, map, &fe->owned_head); |
| if (unlikely(err)) |
| goto err_out; |
| |
| #ifdef EROFS_FS_HAS_MANAGED_CACHE |
| grp = fe->builder.grp; |
| |
| /* let's do out-of-order decompression for noio */ |
| noio_outoforder = grab_managed_cache_pages(mngda, |
| erofs_blknr(map->m_pa), |
| grp->compressed_pages, erofs_blknr(map->m_plen), |
| /* compressed page caching selection strategy */ |
| fe->initial | (EROFS_FS_ZIP_CACHE_LVL >= 2 ? |
| map->m_la < fe->cachedzone_la : 0)); |
| |
| if (noio_outoforder && builder_is_followed(builder)) |
| builder->role = Z_EROFS_VLE_WORK_PRIMARY; |
| #endif |
| |
| tight &= builder_is_followed(builder); |
| work = builder->work; |
| hitted: |
| cur = end - min_t(unsigned, offset + end - map->m_la, end); |
| if (unlikely(!(map->m_flags & EROFS_MAP_MAPPED))) { |
| zero_user_segment(page, cur, end); |
| goto next_part; |
| } |
| |
| /* let's derive page type */ |
| page_type = cur ? Z_EROFS_VLE_PAGE_TYPE_HEAD : |
| (!spiltted ? Z_EROFS_PAGE_TYPE_EXCLUSIVE : |
| (tight ? Z_EROFS_PAGE_TYPE_EXCLUSIVE : |
| Z_EROFS_VLE_PAGE_TYPE_TAIL_SHARED)); |
| |
| retry: |
| err = z_erofs_vle_work_add_page(builder, page, page_type); |
| /* should allocate an additional staging page for pagevec */ |
| if (err == -EAGAIN) { |
| struct page *const newpage = |
| __stagingpage_alloc(page_pool, GFP_NOFS); |
| |
| err = z_erofs_vle_work_add_page(builder, |
| newpage, Z_EROFS_PAGE_TYPE_EXCLUSIVE); |
| if (!err) |
| goto retry; |
| } |
| |
| if (unlikely(err)) |
| goto err_out; |
| |
| index = page->index - map->m_la / PAGE_SIZE; |
| |
| /* FIXME! avoid the last relundant fixup & endio */ |
| z_erofs_onlinepage_fixup(page, index, true); |
| ++spiltted; |
| |
| /* also update nr_pages and increase queued_pages */ |
| work->nr_pages = max_t(pgoff_t, work->nr_pages, index + 1); |
| next_part: |
| /* can be used for verification */ |
| map->m_llen = offset + cur - map->m_la; |
| |
| end = cur; |
| if (end > 0) |
| goto repeat; |
| |
| /* FIXME! avoid the last relundant fixup & endio */ |
| z_erofs_onlinepage_endio(page); |
| |
| debugln("%s, finish page: %pK spiltted: %u map->m_llen %llu", |
| __func__, page, spiltted, map->m_llen); |
| return 0; |
| |
| err_out: |
| /* TODO: the missing error handing cases */ |
| return err; |
| } |
| |
| static void z_erofs_vle_unzip_kickoff(void *ptr, int bios) |
| { |
| tagptr1_t t = tagptr_init(tagptr1_t, ptr); |
| struct z_erofs_vle_unzip_io *io = tagptr_unfold_ptr(t); |
| bool background = tagptr_unfold_tags(t); |
| |
| if (atomic_add_return(bios, &io->pending_bios)) |
| return; |
| |
| if (background) |
| queue_work(z_erofs_workqueue, &io->u.work); |
| else |
| wake_up(&io->u.wait); |
| } |
| |
| static inline void z_erofs_vle_read_endio(struct bio *bio) |
| { |
| const blk_status_t err = bio->bi_status; |
| unsigned i; |
| struct bio_vec *bvec; |
| #ifdef EROFS_FS_HAS_MANAGED_CACHE |
| struct address_space *mngda = NULL; |
| #endif |
| |
| bio_for_each_segment_all(bvec, bio, i) { |
| struct page *page = bvec->bv_page; |
| bool cachemngd = false; |
| |
| DBG_BUGON(PageUptodate(page)); |
| BUG_ON(page->mapping == NULL); |
| |
| #ifdef EROFS_FS_HAS_MANAGED_CACHE |
| if (unlikely(mngda == NULL && !z_erofs_is_stagingpage(page))) { |
| struct inode *const inode = page->mapping->host; |
| struct super_block *const sb = inode->i_sb; |
| |
| mngda = EROFS_SB(sb)->managed_cache->i_mapping; |
| } |
| |
| /* |
| * If mngda has not gotten, it equals NULL, |
| * however, page->mapping never be NULL if working properly. |
| */ |
| cachemngd = (page->mapping == mngda); |
| #endif |
| |
| if (unlikely(err)) |
| SetPageError(page); |
| else if (cachemngd) |
| SetPageUptodate(page); |
| |
| if (cachemngd) |
| unlock_page(page); |
| } |
| |
| z_erofs_vle_unzip_kickoff(bio->bi_private, -1); |
| bio_put(bio); |
| } |
| |
| static struct page *z_pagemap_global[Z_EROFS_VLE_VMAP_GLOBAL_PAGES]; |
| static DEFINE_MUTEX(z_pagemap_global_lock); |
| |
| static int z_erofs_vle_unzip(struct super_block *sb, |
| struct z_erofs_vle_workgroup *grp, |
| struct list_head *page_pool) |
| { |
| struct erofs_sb_info *const sbi = EROFS_SB(sb); |
| #ifdef EROFS_FS_HAS_MANAGED_CACHE |
| struct address_space *const mngda = sbi->managed_cache->i_mapping; |
| #endif |
| const unsigned clusterpages = erofs_clusterpages(sbi); |
| |
| struct z_erofs_pagevec_ctor ctor; |
| unsigned nr_pages; |
| #ifndef CONFIG_EROFS_FS_ZIP_MULTIREF |
| unsigned sparsemem_pages = 0; |
| #endif |
| struct page *pages_onstack[Z_EROFS_VLE_VMAP_ONSTACK_PAGES]; |
| struct page **pages, **compressed_pages, *page; |
| unsigned i, llen; |
| |
| enum z_erofs_page_type page_type; |
| bool overlapped; |
| struct z_erofs_vle_work *work; |
| void *vout; |
| int err; |
| |
| might_sleep(); |
| #ifndef CONFIG_EROFS_FS_ZIP_MULTIREF |
| work = z_erofs_vle_grab_primary_work(grp); |
| #else |
| BUG(); |
| #endif |
| BUG_ON(!READ_ONCE(work->nr_pages)); |
| |
| mutex_lock(&work->lock); |
| nr_pages = work->nr_pages; |
| |
| if (likely(nr_pages <= Z_EROFS_VLE_VMAP_ONSTACK_PAGES)) |
| pages = pages_onstack; |
| else if (nr_pages <= Z_EROFS_VLE_VMAP_GLOBAL_PAGES && |
| mutex_trylock(&z_pagemap_global_lock)) |
| pages = z_pagemap_global; |
| else { |
| repeat: |
| pages = kvmalloc_array(nr_pages, |
| sizeof(struct page *), GFP_KERNEL); |
| |
| /* fallback to global pagemap for the lowmem scenario */ |
| if (unlikely(pages == NULL)) { |
| if (nr_pages > Z_EROFS_VLE_VMAP_GLOBAL_PAGES) |
| goto repeat; |
| else { |
| mutex_lock(&z_pagemap_global_lock); |
| pages = z_pagemap_global; |
| } |
| } |
| } |
| |
| for (i = 0; i < nr_pages; ++i) |
| pages[i] = NULL; |
| |
| z_erofs_pagevec_ctor_init(&ctor, |
| Z_EROFS_VLE_INLINE_PAGEVECS, work->pagevec, 0); |
| |
| for (i = 0; i < work->vcnt; ++i) { |
| unsigned pagenr; |
| |
| page = z_erofs_pagevec_ctor_dequeue(&ctor, &page_type); |
| |
| /* all pages in pagevec ought to be valid */ |
| DBG_BUGON(page == NULL); |
| DBG_BUGON(page->mapping == NULL); |
| |
| if (z_erofs_gather_if_stagingpage(page_pool, page)) |
| continue; |
| |
| if (page_type == Z_EROFS_VLE_PAGE_TYPE_HEAD) |
| pagenr = 0; |
| else |
| pagenr = z_erofs_onlinepage_index(page); |
| |
| BUG_ON(pagenr >= nr_pages); |
| |
| #ifndef CONFIG_EROFS_FS_ZIP_MULTIREF |
| BUG_ON(pages[pagenr] != NULL); |
| ++sparsemem_pages; |
| #endif |
| pages[pagenr] = page; |
| } |
| |
| z_erofs_pagevec_ctor_exit(&ctor, true); |
| |
| overlapped = false; |
| compressed_pages = grp->compressed_pages; |
| |
| for (i = 0; i < clusterpages; ++i) { |
| unsigned pagenr; |
| |
| page = compressed_pages[i]; |
| |
| /* all compressed pages ought to be valid */ |
| DBG_BUGON(page == NULL); |
| DBG_BUGON(page->mapping == NULL); |
| |
| if (z_erofs_is_stagingpage(page)) |
| continue; |
| #ifdef EROFS_FS_HAS_MANAGED_CACHE |
| else if (page->mapping == mngda) { |
| BUG_ON(PageLocked(page)); |
| BUG_ON(!PageUptodate(page)); |
| continue; |
| } |
| #endif |
| |
| /* only non-head page could be reused as a compressed page */ |
| pagenr = z_erofs_onlinepage_index(page); |
| |
| BUG_ON(pagenr >= nr_pages); |
| #ifndef CONFIG_EROFS_FS_ZIP_MULTIREF |
| BUG_ON(pages[pagenr] != NULL); |
| ++sparsemem_pages; |
| #endif |
| pages[pagenr] = page; |
| |
| overlapped = true; |
| } |
| |
| llen = (nr_pages << PAGE_SHIFT) - work->pageofs; |
| |
| if (z_erofs_vle_workgrp_fmt(grp) == Z_EROFS_VLE_WORKGRP_FMT_PLAIN) { |
| /* FIXME! this should be fixed in the future */ |
| BUG_ON(grp->llen != llen); |
| |
| err = z_erofs_vle_plain_copy(compressed_pages, clusterpages, |
| pages, nr_pages, work->pageofs); |
| goto out; |
| } |
| |
| if (llen > grp->llen) |
| llen = grp->llen; |
| |
| err = z_erofs_vle_unzip_fast_percpu(compressed_pages, |
| clusterpages, pages, llen, work->pageofs, |
| z_erofs_onlinepage_endio); |
| if (err != -ENOTSUPP) |
| goto out_percpu; |
| |
| #ifndef CONFIG_EROFS_FS_ZIP_MULTIREF |
| if (sparsemem_pages >= nr_pages) { |
| BUG_ON(sparsemem_pages > nr_pages); |
| goto skip_allocpage; |
| } |
| #endif |
| |
| for (i = 0; i < nr_pages; ++i) { |
| if (pages[i] != NULL) |
| continue; |
| |
| pages[i] = __stagingpage_alloc(page_pool, GFP_NOFS); |
| } |
| |
| #ifndef CONFIG_EROFS_FS_ZIP_MULTIREF |
| skip_allocpage: |
| #endif |
| vout = erofs_vmap(pages, nr_pages); |
| |
| err = z_erofs_vle_unzip_vmap(compressed_pages, |
| clusterpages, vout, llen, work->pageofs, overlapped); |
| |
| erofs_vunmap(vout, nr_pages); |
| |
| out: |
| for (i = 0; i < nr_pages; ++i) { |
| page = pages[i]; |
| DBG_BUGON(page->mapping == NULL); |
| |
| /* recycle all individual staging pages */ |
| if (z_erofs_gather_if_stagingpage(page_pool, page)) |
| continue; |
| |
| if (unlikely(err < 0)) |
| SetPageError(page); |
| |
| z_erofs_onlinepage_endio(page); |
| } |
| |
| out_percpu: |
| for (i = 0; i < clusterpages; ++i) { |
| page = compressed_pages[i]; |
| |
| #ifdef EROFS_FS_HAS_MANAGED_CACHE |
| if (page->mapping == mngda) |
| continue; |
| #endif |
| /* recycle all individual staging pages */ |
| (void)z_erofs_gather_if_stagingpage(page_pool, page); |
| |
| WRITE_ONCE(compressed_pages[i], NULL); |
| } |
| |
| if (pages == z_pagemap_global) |
| mutex_unlock(&z_pagemap_global_lock); |
| else if (unlikely(pages != pages_onstack)) |
| kvfree(pages); |
| |
| work->nr_pages = 0; |
| work->vcnt = 0; |
| |
| /* all work locks MUST be taken before the following line */ |
| |
| WRITE_ONCE(grp->next, Z_EROFS_VLE_WORKGRP_NIL); |
| |
| /* all work locks SHOULD be released right now */ |
| mutex_unlock(&work->lock); |
| |
| z_erofs_vle_work_release(work); |
| return err; |
| } |
| |
| static void z_erofs_vle_unzip_all(struct super_block *sb, |
| struct z_erofs_vle_unzip_io *io, |
| struct list_head *page_pool) |
| { |
| z_erofs_vle_owned_workgrp_t owned = io->head; |
| |
| while (owned != Z_EROFS_VLE_WORKGRP_TAIL_CLOSED) { |
| struct z_erofs_vle_workgroup *grp; |
| |
| /* no possible that 'owned' equals Z_EROFS_WORK_TPTR_TAIL */ |
| DBG_BUGON(owned == Z_EROFS_VLE_WORKGRP_TAIL); |
| |
| /* no possible that 'owned' equals NULL */ |
| DBG_BUGON(owned == Z_EROFS_VLE_WORKGRP_NIL); |
| |
| grp = owned; |
| owned = READ_ONCE(grp->next); |
| |
| z_erofs_vle_unzip(sb, grp, page_pool); |
| } |
| } |
| |
| static void z_erofs_vle_unzip_wq(struct work_struct *work) |
| { |
| struct z_erofs_vle_unzip_io_sb *iosb = container_of(work, |
| struct z_erofs_vle_unzip_io_sb, io.u.work); |
| LIST_HEAD(page_pool); |
| |
| BUG_ON(iosb->io.head == Z_EROFS_VLE_WORKGRP_TAIL_CLOSED); |
| z_erofs_vle_unzip_all(iosb->sb, &iosb->io, &page_pool); |
| |
| put_pages_list(&page_pool); |
| kvfree(iosb); |
| } |
| |
| static inline struct z_erofs_vle_unzip_io * |
| prepare_io_handler(struct super_block *sb, |
| struct z_erofs_vle_unzip_io *io, |
| bool background) |
| { |
| struct z_erofs_vle_unzip_io_sb *iosb; |
| |
| if (!background) { |
| /* waitqueue available for foreground io */ |
| BUG_ON(io == NULL); |
| |
| init_waitqueue_head(&io->u.wait); |
| atomic_set(&io->pending_bios, 0); |
| goto out; |
| } |
| |
| if (io != NULL) |
| BUG(); |
| else { |
| /* allocate extra io descriptor for background io */ |
| iosb = kvzalloc(sizeof(struct z_erofs_vle_unzip_io_sb), |
| GFP_KERNEL | __GFP_NOFAIL); |
| BUG_ON(iosb == NULL); |
| |
| io = &iosb->io; |
| } |
| |
| iosb->sb = sb; |
| INIT_WORK(&io->u.work, z_erofs_vle_unzip_wq); |
| out: |
| io->head = Z_EROFS_VLE_WORKGRP_TAIL_CLOSED; |
| return io; |
| } |
| |
| #ifdef EROFS_FS_HAS_MANAGED_CACHE |
| /* true - unlocked (noio), false - locked (need submit io) */ |
| static inline bool recover_managed_page(struct z_erofs_vle_workgroup *grp, |
| struct page *page) |
| { |
| wait_on_page_locked(page); |
| if (PagePrivate(page) && PageUptodate(page)) |
| return true; |
| |
| lock_page(page); |
| if (unlikely(!PagePrivate(page))) { |
| set_page_private(page, (unsigned long)grp); |
| SetPagePrivate(page); |
| } |
| if (unlikely(PageUptodate(page))) { |
| unlock_page(page); |
| return true; |
| } |
| return false; |
| } |
| |
| #define __FSIO_1 1 |
| #else |
| #define __FSIO_1 0 |
| #endif |
| |
| static bool z_erofs_vle_submit_all(struct super_block *sb, |
| z_erofs_vle_owned_workgrp_t owned_head, |
| struct list_head *pagepool, |
| struct z_erofs_vle_unzip_io *fg_io, |
| bool force_fg) |
| { |
| struct erofs_sb_info *const sbi = EROFS_SB(sb); |
| const unsigned clusterpages = erofs_clusterpages(sbi); |
| const gfp_t gfp = GFP_NOFS; |
| #ifdef EROFS_FS_HAS_MANAGED_CACHE |
| struct address_space *const mngda = sbi->managed_cache->i_mapping; |
| struct z_erofs_vle_workgroup *lstgrp_noio = NULL, *lstgrp_io = NULL; |
| #endif |
| struct z_erofs_vle_unzip_io *ios[1 + __FSIO_1]; |
| struct bio *bio; |
| tagptr1_t bi_private; |
| /* since bio will be NULL, no need to initialize last_index */ |
| pgoff_t uninitialized_var(last_index); |
| bool force_submit = false; |
| unsigned nr_bios; |
| |
| if (unlikely(owned_head == Z_EROFS_VLE_WORKGRP_TAIL)) |
| return false; |
| |
| /* |
| * force_fg == 1, (io, fg_io[0]) no io, (io, fg_io[1]) need submit io |
| * force_fg == 0, (io, fg_io[0]) no io; (io[1], bg_io) need submit io |
| */ |
| #ifdef EROFS_FS_HAS_MANAGED_CACHE |
| ios[0] = prepare_io_handler(sb, fg_io + 0, false); |
| #endif |
| |
| if (force_fg) { |
| ios[__FSIO_1] = prepare_io_handler(sb, fg_io + __FSIO_1, false); |
| bi_private = tagptr_fold(tagptr1_t, ios[__FSIO_1], 0); |
| } else { |
| ios[__FSIO_1] = prepare_io_handler(sb, NULL, true); |
| bi_private = tagptr_fold(tagptr1_t, ios[__FSIO_1], 1); |
| } |
| |
| nr_bios = 0; |
| force_submit = false; |
| bio = NULL; |
| |
| /* by default, all need io submission */ |
| ios[__FSIO_1]->head = owned_head; |
| |
| do { |
| struct z_erofs_vle_workgroup *grp; |
| struct page **compressed_pages, *oldpage, *page; |
| pgoff_t first_index; |
| unsigned i = 0; |
| #ifdef EROFS_FS_HAS_MANAGED_CACHE |
| unsigned int noio = 0; |
| bool cachemngd; |
| #endif |
| int err; |
| |
| /* no possible 'owned_head' equals the following */ |
| DBG_BUGON(owned_head == Z_EROFS_VLE_WORKGRP_TAIL_CLOSED); |
| DBG_BUGON(owned_head == Z_EROFS_VLE_WORKGRP_NIL); |
| |
| grp = owned_head; |
| |
| /* close the main owned chain at first */ |
| owned_head = cmpxchg(&grp->next, Z_EROFS_VLE_WORKGRP_TAIL, |
| Z_EROFS_VLE_WORKGRP_TAIL_CLOSED); |
| |
| first_index = grp->obj.index; |
| compressed_pages = grp->compressed_pages; |
| |
| force_submit |= (first_index != last_index + 1); |
| repeat: |
| /* fulfill all compressed pages */ |
| oldpage = page = READ_ONCE(compressed_pages[i]); |
| |
| #ifdef EROFS_FS_HAS_MANAGED_CACHE |
| cachemngd = false; |
| |
| if (page == EROFS_UNALLOCATED_CACHED_PAGE) { |
| cachemngd = true; |
| goto do_allocpage; |
| } else if (page != NULL) { |
| if (page->mapping != mngda) |
| BUG_ON(PageUptodate(page)); |
| else if (recover_managed_page(grp, page)) { |
| /* page is uptodate, skip io submission */ |
| force_submit = true; |
| ++noio; |
| goto skippage; |
| } |
| } else { |
| do_allocpage: |
| #else |
| if (page != NULL) |
| BUG_ON(PageUptodate(page)); |
| else { |
| #endif |
| page = __stagingpage_alloc(pagepool, gfp); |
| |
| if (oldpage != cmpxchg(compressed_pages + i, |
| oldpage, page)) { |
| list_add(&page->lru, pagepool); |
| goto repeat; |
| #ifdef EROFS_FS_HAS_MANAGED_CACHE |
| } else if (cachemngd && !add_to_page_cache_lru(page, |
| mngda, first_index + i, gfp)) { |
| set_page_private(page, (unsigned long)grp); |
| SetPagePrivate(page); |
| #endif |
| } |
| } |
| |
| if (bio != NULL && force_submit) { |
| submit_bio_retry: |
| __submit_bio(bio, REQ_OP_READ, 0); |
| bio = NULL; |
| } |
| |
| if (bio == NULL) { |
| bio = prepare_bio(sb, first_index + i, |
| BIO_MAX_PAGES, z_erofs_vle_read_endio); |
| bio->bi_private = tagptr_cast_ptr(bi_private); |
| |
| ++nr_bios; |
| } |
| |
| err = bio_add_page(bio, page, PAGE_SIZE, 0); |
| if (err < PAGE_SIZE) |
| goto submit_bio_retry; |
| |
| force_submit = false; |
| last_index = first_index + i; |
| #ifdef EROFS_FS_HAS_MANAGED_CACHE |
| skippage: |
| #endif |
| if (++i < clusterpages) |
| goto repeat; |
| |
| #ifdef EROFS_FS_HAS_MANAGED_CACHE |
| if (noio < clusterpages) { |
| lstgrp_io = grp; |
| } else { |
| z_erofs_vle_owned_workgrp_t iogrp_next = |
| owned_head == Z_EROFS_VLE_WORKGRP_TAIL ? |
| Z_EROFS_VLE_WORKGRP_TAIL_CLOSED : |
| owned_head; |
| |
| if (lstgrp_io == NULL) |
| ios[1]->head = iogrp_next; |
| else |
| WRITE_ONCE(lstgrp_io->next, iogrp_next); |
| |
| if (lstgrp_noio == NULL) |
| ios[0]->head = grp; |
| else |
| WRITE_ONCE(lstgrp_noio->next, grp); |
| |
| lstgrp_noio = grp; |
| } |
| #endif |
| } while (owned_head != Z_EROFS_VLE_WORKGRP_TAIL); |
| |
| if (bio != NULL) |
| __submit_bio(bio, REQ_OP_READ, 0); |
| |
| #ifndef EROFS_FS_HAS_MANAGED_CACHE |
| BUG_ON(!nr_bios); |
| #else |
| if (lstgrp_noio != NULL) |
| WRITE_ONCE(lstgrp_noio->next, Z_EROFS_VLE_WORKGRP_TAIL_CLOSED); |
| |
| if (!force_fg && !nr_bios) { |
| kvfree(container_of(ios[1], |
| struct z_erofs_vle_unzip_io_sb, io)); |
| return true; |
| } |
| #endif |
| |
| z_erofs_vle_unzip_kickoff(tagptr_cast_ptr(bi_private), nr_bios); |
| return true; |
| } |
| |
| static void z_erofs_submit_and_unzip(struct z_erofs_vle_frontend *f, |
| struct list_head *pagepool, |
| bool force_fg) |
| { |
| struct super_block *sb = f->inode->i_sb; |
| struct z_erofs_vle_unzip_io io[1 + __FSIO_1]; |
| |
| if (!z_erofs_vle_submit_all(sb, f->owned_head, pagepool, io, force_fg)) |
| return; |
| |
| #ifdef EROFS_FS_HAS_MANAGED_CACHE |
| z_erofs_vle_unzip_all(sb, &io[0], pagepool); |
| #endif |
| if (!force_fg) |
| return; |
| |
| /* wait until all bios are completed */ |
| wait_event(io[__FSIO_1].u.wait, |
| !atomic_read(&io[__FSIO_1].pending_bios)); |
| |
| /* let's synchronous decompression */ |
| z_erofs_vle_unzip_all(sb, &io[__FSIO_1], pagepool); |
| } |
| |
| static int z_erofs_vle_normalaccess_readpage(struct file *file, |
| struct page *page) |
| { |
| struct inode *const inode = page->mapping->host; |
| struct z_erofs_vle_frontend f = VLE_FRONTEND_INIT(inode); |
| int err; |
| LIST_HEAD(pagepool); |
| |
| #if (EROFS_FS_ZIP_CACHE_LVL >= 2) |
| f.cachedzone_la = page->index << PAGE_SHIFT; |
| #endif |
| err = z_erofs_do_read_page(&f, page, &pagepool); |
| (void)z_erofs_vle_work_iter_end(&f.builder); |
| |
| if (err) { |
| errln("%s, failed to read, err [%d]", __func__, err); |
| goto out; |
| } |
| |
| z_erofs_submit_and_unzip(&f, &pagepool, true); |
| out: |
| if (f.m_iter.mpage != NULL) |
| put_page(f.m_iter.mpage); |
| |
| /* clean up the remaining free pages */ |
| put_pages_list(&pagepool); |
| return 0; |
| } |
| |
| static inline int __z_erofs_vle_normalaccess_readpages( |
| struct file *filp, |
| struct address_space *mapping, |
| struct list_head *pages, unsigned nr_pages, bool sync) |
| { |
| struct inode *const inode = mapping->host; |
| |
| struct z_erofs_vle_frontend f = VLE_FRONTEND_INIT(inode); |
| gfp_t gfp = mapping_gfp_constraint(mapping, GFP_KERNEL); |
| struct page *head = NULL; |
| LIST_HEAD(pagepool); |
| |
| #if (EROFS_FS_ZIP_CACHE_LVL >= 2) |
| f.cachedzone_la = lru_to_page(pages)->index << PAGE_SHIFT; |
| #endif |
| for (; nr_pages; --nr_pages) { |
| struct page *page = lru_to_page(pages); |
| |
| prefetchw(&page->flags); |
| list_del(&page->lru); |
| |
| if (add_to_page_cache_lru(page, mapping, page->index, gfp)) { |
| list_add(&page->lru, &pagepool); |
| continue; |
| } |
| |
| BUG_ON(PagePrivate(page)); |
| set_page_private(page, (unsigned long)head); |
| head = page; |
| } |
| |
| while (head != NULL) { |
| struct page *page = head; |
| int err; |
| |
| /* traversal in reverse order */ |
| head = (void *)page_private(page); |
| |
| err = z_erofs_do_read_page(&f, page, &pagepool); |
| if (err) { |
| struct erofs_vnode *vi = EROFS_V(inode); |
| |
| errln("%s, readahead error at page %lu of nid %llu", |
| __func__, page->index, vi->nid); |
| } |
| |
| put_page(page); |
| } |
| |
| (void)z_erofs_vle_work_iter_end(&f.builder); |
| |
| z_erofs_submit_and_unzip(&f, &pagepool, sync); |
| |
| if (f.m_iter.mpage != NULL) |
| put_page(f.m_iter.mpage); |
| |
| /* clean up the remaining free pages */ |
| put_pages_list(&pagepool); |
| return 0; |
| } |
| |
| static int z_erofs_vle_normalaccess_readpages( |
| struct file *filp, |
| struct address_space *mapping, |
| struct list_head *pages, unsigned nr_pages) |
| { |
| return __z_erofs_vle_normalaccess_readpages(filp, |
| mapping, pages, nr_pages, |
| nr_pages < 4 /* sync */); |
| } |
| |
| const struct address_space_operations z_erofs_vle_normalaccess_aops = { |
| .readpage = z_erofs_vle_normalaccess_readpage, |
| .readpages = z_erofs_vle_normalaccess_readpages, |
| }; |
| |
| #define __vle_cluster_advise(x, bit, bits) \ |
| ((le16_to_cpu(x) >> (bit)) & ((1 << (bits)) - 1)) |
| |
| #define __vle_cluster_type(advise) __vle_cluster_advise(advise, \ |
| Z_EROFS_VLE_DI_CLUSTER_TYPE_BIT, Z_EROFS_VLE_DI_CLUSTER_TYPE_BITS) |
| |
| enum { |
| Z_EROFS_VLE_CLUSTER_TYPE_PLAIN, |
| Z_EROFS_VLE_CLUSTER_TYPE_HEAD, |
| Z_EROFS_VLE_CLUSTER_TYPE_NONHEAD, |
| Z_EROFS_VLE_CLUSTER_TYPE_RESERVED, |
| Z_EROFS_VLE_CLUSTER_TYPE_MAX |
| }; |
| |
| #define vle_cluster_type(di) \ |
| __vle_cluster_type((di)->di_advise) |
| |
| static inline unsigned |
| vle_compressed_index_clusterofs(unsigned clustersize, |
| struct z_erofs_vle_decompressed_index *di) |
| { |
| debugln("%s, vle=%pK, advise=%x (type %u), clusterofs=%x blkaddr=%x", |
| __func__, di, di->di_advise, vle_cluster_type(di), |
| di->di_clusterofs, di->di_u.blkaddr); |
| |
| switch (vle_cluster_type(di)) { |
| case Z_EROFS_VLE_CLUSTER_TYPE_NONHEAD: |
| break; |
| case Z_EROFS_VLE_CLUSTER_TYPE_PLAIN: |
| case Z_EROFS_VLE_CLUSTER_TYPE_HEAD: |
| return di->di_clusterofs; |
| default: |
| BUG_ON(1); |
| } |
| return clustersize; |
| } |
| |
| static inline erofs_blk_t |
| vle_extent_blkaddr(struct inode *inode, pgoff_t index) |
| { |
| struct erofs_sb_info *sbi = EROFS_I_SB(inode); |
| struct erofs_vnode *vi = EROFS_V(inode); |
| |
| unsigned ofs = Z_EROFS_VLE_EXTENT_ALIGN(vi->inode_isize + |
| vi->xattr_isize) + sizeof(struct erofs_extent_header) + |
| index * sizeof(struct z_erofs_vle_decompressed_index); |
| |
| return erofs_blknr(iloc(sbi, vi->nid) + ofs); |
| } |
| |
| static inline unsigned int |
| vle_extent_blkoff(struct inode *inode, pgoff_t index) |
| { |
| struct erofs_sb_info *sbi = EROFS_I_SB(inode); |
| struct erofs_vnode *vi = EROFS_V(inode); |
| |
| unsigned ofs = Z_EROFS_VLE_EXTENT_ALIGN(vi->inode_isize + |
| vi->xattr_isize) + sizeof(struct erofs_extent_header) + |
| index * sizeof(struct z_erofs_vle_decompressed_index); |
| |
| return erofs_blkoff(iloc(sbi, vi->nid) + ofs); |
| } |
| |
| /* |
| * Variable-sized Logical Extent (Fixed Physical Cluster) Compression Mode |
| * --- |
| * VLE compression mode attempts to compress a number of logical data into |
| * a physical cluster with a fixed size. |
| * VLE compression mode uses "struct z_erofs_vle_decompressed_index". |
| */ |
| static erofs_off_t vle_get_logical_extent_head( |
| struct inode *inode, |
| struct page **page_iter, |
| void **kaddr_iter, |
| unsigned lcn, /* logical cluster number */ |
| erofs_blk_t *pcn, |
| unsigned *flags) |
| { |
| /* for extent meta */ |
| struct page *page = *page_iter; |
| erofs_blk_t blkaddr = vle_extent_blkaddr(inode, lcn); |
| struct z_erofs_vle_decompressed_index *di; |
| unsigned long long ofs; |
| const unsigned int clusterbits = EROFS_SB(inode->i_sb)->clusterbits; |
| const unsigned int clustersize = 1 << clusterbits; |
| |
| if (page->index != blkaddr) { |
| kunmap_atomic(*kaddr_iter); |
| unlock_page(page); |
| put_page(page); |
| |
| *page_iter = page = erofs_get_meta_page(inode->i_sb, |
| blkaddr, false); |
| *kaddr_iter = kmap_atomic(page); |
| } |
| |
| di = *kaddr_iter + vle_extent_blkoff(inode, lcn); |
| switch (vle_cluster_type(di)) { |
| case Z_EROFS_VLE_CLUSTER_TYPE_NONHEAD: |
| BUG_ON(!di->di_u.delta[0]); |
| BUG_ON(lcn < di->di_u.delta[0]); |
| |
| ofs = vle_get_logical_extent_head(inode, |
| page_iter, kaddr_iter, |
| lcn - di->di_u.delta[0], pcn, flags); |
| break; |
| case Z_EROFS_VLE_CLUSTER_TYPE_PLAIN: |
| *flags ^= EROFS_MAP_ZIPPED; |
| case Z_EROFS_VLE_CLUSTER_TYPE_HEAD: |
| /* clustersize should be a power of two */ |
| ofs = ((unsigned long long)lcn << clusterbits) + |
| (le16_to_cpu(di->di_clusterofs) & (clustersize - 1)); |
| *pcn = le32_to_cpu(di->di_u.blkaddr); |
| break; |
| default: |
| BUG_ON(1); |
| } |
| return ofs; |
| } |
| |
| int z_erofs_map_blocks_iter(struct inode *inode, |
| struct erofs_map_blocks *map, |
| struct page **mpage_ret, int flags) |
| { |
| /* logicial extent (start, end) offset */ |
| unsigned long long ofs, end; |
| struct z_erofs_vle_decompressed_index *di; |
| erofs_blk_t e_blkaddr, pcn; |
| unsigned lcn, logical_cluster_ofs, cluster_type; |
| u32 ofs_rem; |
| struct page *mpage = *mpage_ret; |
| void *kaddr; |
| bool initial; |
| const unsigned int clusterbits = EROFS_SB(inode->i_sb)->clusterbits; |
| const unsigned int clustersize = 1 << clusterbits; |
| int err = 0; |
| |
| /* if both m_(l,p)len are 0, regularize l_lblk, l_lofs, etc... */ |
| initial = !map->m_llen; |
| |
| /* when trying to read beyond EOF, leave it unmapped */ |
| if (unlikely(map->m_la >= inode->i_size)) { |
| BUG_ON(!initial); |
| map->m_llen = map->m_la + 1 - inode->i_size; |
| map->m_la = inode->i_size - 1; |
| map->m_flags = 0; |
| goto out; |
| } |
| |
| debugln("%s, m_la %llu m_llen %llu --- start", __func__, |
| map->m_la, map->m_llen); |
| |
| ofs = map->m_la + map->m_llen; |
| |
| /* clustersize should be power of two */ |
| lcn = ofs >> clusterbits; |
| ofs_rem = ofs & (clustersize - 1); |
| |
| e_blkaddr = vle_extent_blkaddr(inode, lcn); |
| |
| if (mpage == NULL || mpage->index != e_blkaddr) { |
| if (mpage != NULL) |
| put_page(mpage); |
| |
| mpage = erofs_get_meta_page(inode->i_sb, e_blkaddr, false); |
| *mpage_ret = mpage; |
| } else { |
| lock_page(mpage); |
| DBG_BUGON(!PageUptodate(mpage)); |
| } |
| |
| kaddr = kmap_atomic(mpage); |
| di = kaddr + vle_extent_blkoff(inode, lcn); |
| |
| debugln("%s, lcn %u e_blkaddr %u e_blkoff %u", __func__, lcn, |
| e_blkaddr, vle_extent_blkoff(inode, lcn)); |
| |
| logical_cluster_ofs = vle_compressed_index_clusterofs(clustersize, di); |
| if (!initial) { |
| /* [walking mode] 'map' has been already initialized */ |
| map->m_llen += logical_cluster_ofs; |
| goto unmap_out; |
| } |
| |
| /* by default, compressed */ |
| map->m_flags |= EROFS_MAP_ZIPPED; |
| |
| end = (u64)(lcn + 1) * clustersize; |
| |
| cluster_type = vle_cluster_type(di); |
| |
| switch (cluster_type) { |
| case Z_EROFS_VLE_CLUSTER_TYPE_PLAIN: |
| if (ofs_rem >= logical_cluster_ofs) |
| map->m_flags ^= EROFS_MAP_ZIPPED; |
| /* fallthrough */ |
| case Z_EROFS_VLE_CLUSTER_TYPE_HEAD: |
| if (ofs_rem == logical_cluster_ofs) { |
| pcn = le32_to_cpu(di->di_u.blkaddr); |
| goto exact_hitted; |
| } |
| |
| if (ofs_rem > logical_cluster_ofs) { |
| ofs = lcn * clustersize | logical_cluster_ofs; |
| pcn = le32_to_cpu(di->di_u.blkaddr); |
| break; |
| } |
| |
| /* logical cluster number should be >= 1 */ |
| if (unlikely(!lcn)) { |
| errln("invalid logical cluster 0 at nid %llu", |
| EROFS_V(inode)->nid); |
| err = -EIO; |
| goto unmap_out; |
| } |
| end = (lcn-- * clustersize) | logical_cluster_ofs; |
| /* fallthrough */ |
| case Z_EROFS_VLE_CLUSTER_TYPE_NONHEAD: |
| /* get the correspoinding first chunk */ |
| ofs = vle_get_logical_extent_head(inode, mpage_ret, |
| &kaddr, lcn, &pcn, &map->m_flags); |
| mpage = *mpage_ret; |
| break; |
| default: |
| errln("unknown cluster type %u at offset %llu of nid %llu", |
| cluster_type, ofs, EROFS_V(inode)->nid); |
| err = -EIO; |
| goto unmap_out; |
| } |
| |
| map->m_la = ofs; |
| exact_hitted: |
| map->m_llen = end - ofs; |
| map->m_plen = clustersize; |
| map->m_pa = blknr_to_addr(pcn); |
| map->m_flags |= EROFS_MAP_MAPPED; |
| unmap_out: |
| kunmap_atomic(kaddr); |
| unlock_page(mpage); |
| out: |
| debugln("%s, m_la %llu m_pa %llu m_llen %llu m_plen %llu m_flags 0%o", |
| __func__, map->m_la, map->m_pa, |
| map->m_llen, map->m_plen, map->m_flags); |
| |
| /* aggressively BUG_ON iff CONFIG_EROFS_FS_DEBUG is on */ |
| DBG_BUGON(err < 0); |
| return err; |
| } |
| |