diff options
Diffstat (limited to 'drivers/staging/erofs/unzip_vle.h')
| -rw-r--r-- | drivers/staging/erofs/unzip_vle.h | 239 |
1 files changed, 239 insertions, 0 deletions
diff --git a/drivers/staging/erofs/unzip_vle.h b/drivers/staging/erofs/unzip_vle.h new file mode 100644 index 000000000000..393998500865 --- /dev/null +++ b/drivers/staging/erofs/unzip_vle.h @@ -0,0 +1,239 @@ +/* SPDX-License-Identifier: GPL-2.0 + * + * linux/drivers/staging/erofs/unzip_vle.h + * + * 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. + */ +#ifndef __EROFS_FS_UNZIP_VLE_H +#define __EROFS_FS_UNZIP_VLE_H + +#include "internal.h" +#include "unzip_pagevec.h" + +/* + * - 0x5A110C8D ('sallocated', Z_EROFS_MAPPING_STAGING) - + * used for temporary allocated pages (via erofs_allocpage), + * in order to seperate those from NULL mapping (eg. truncated pages) + */ +#define Z_EROFS_MAPPING_STAGING ((void *)0x5A110C8D) + +#define z_erofs_is_stagingpage(page) \ + ((page)->mapping == Z_EROFS_MAPPING_STAGING) + +static inline bool z_erofs_gather_if_stagingpage(struct list_head *page_pool, + struct page *page) +{ + if (z_erofs_is_stagingpage(page)) { + list_add(&page->lru, page_pool); + return true; + } + return false; +} + +/* + * Structure fields follow one of the following exclusion rules. + * + * I: Modifiable by initialization/destruction paths and read-only + * for everyone else. + * + */ + +#define Z_EROFS_VLE_INLINE_PAGEVECS 3 + +struct z_erofs_vle_work { + /* struct z_erofs_vle_work *left, *right; */ + +#ifdef CONFIG_EROFS_FS_ZIP_MULTIREF + struct list_head list; + + atomic_t refcount; +#endif + struct mutex lock; + + /* I: decompression offset in page */ + unsigned short pageofs; + unsigned short nr_pages; + + /* L: queued pages in pagevec[] */ + unsigned vcnt; + + union { + /* L: pagevec */ + erofs_vtptr_t pagevec[Z_EROFS_VLE_INLINE_PAGEVECS]; + struct rcu_head rcu; + }; +}; + +#define Z_EROFS_VLE_WORKGRP_FMT_PLAIN 0 +#define Z_EROFS_VLE_WORKGRP_FMT_LZ4 1 +#define Z_EROFS_VLE_WORKGRP_FMT_MASK 1 + +typedef struct z_erofs_vle_workgroup *z_erofs_vle_owned_workgrp_t; + +struct z_erofs_vle_workgroup { + struct erofs_workgroup obj; + struct z_erofs_vle_work work; + + /* next owned workgroup */ + z_erofs_vle_owned_workgrp_t next; + + /* compressed pages (including multi-usage pages) */ + struct page *compressed_pages[Z_EROFS_CLUSTER_MAX_PAGES]; + unsigned int llen, flags; +}; + +/* let's avoid the valid 32-bit kernel addresses */ + +/* the chained workgroup has't submitted io (still open) */ +#define Z_EROFS_VLE_WORKGRP_TAIL ((void *)0x5F0ECAFE) +/* the chained workgroup has already submitted io */ +#define Z_EROFS_VLE_WORKGRP_TAIL_CLOSED ((void *)0x5F0EDEAD) + +#define Z_EROFS_VLE_WORKGRP_NIL (NULL) + +#define z_erofs_vle_workgrp_fmt(grp) \ + ((grp)->flags & Z_EROFS_VLE_WORKGRP_FMT_MASK) + +static inline void z_erofs_vle_set_workgrp_fmt( + struct z_erofs_vle_workgroup *grp, + unsigned int fmt) +{ + grp->flags = fmt | (grp->flags & ~Z_EROFS_VLE_WORKGRP_FMT_MASK); +} + +#ifdef CONFIG_EROFS_FS_ZIP_MULTIREF +#error multiref decompression is unimplemented yet +#else + +#define z_erofs_vle_grab_primary_work(grp) (&(grp)->work) +#define z_erofs_vle_grab_work(grp, pageofs) (&(grp)->work) +#define z_erofs_vle_work_workgroup(wrk, primary) \ + ((primary) ? container_of(wrk, \ + struct z_erofs_vle_workgroup, work) : \ + ({ BUG(); (void *)NULL; })) + +#endif + +#define Z_EROFS_WORKGROUP_SIZE sizeof(struct z_erofs_vle_workgroup) + +struct z_erofs_vle_unzip_io { + atomic_t pending_bios; + z_erofs_vle_owned_workgrp_t head; + + union { + wait_queue_head_t wait; + struct work_struct work; + } u; +}; + +struct z_erofs_vle_unzip_io_sb { + struct z_erofs_vle_unzip_io io; + struct super_block *sb; +}; + +#define Z_EROFS_ONLINEPAGE_COUNT_BITS 2 +#define Z_EROFS_ONLINEPAGE_COUNT_MASK ((1 << Z_EROFS_ONLINEPAGE_COUNT_BITS) - 1) +#define Z_EROFS_ONLINEPAGE_INDEX_SHIFT (Z_EROFS_ONLINEPAGE_COUNT_BITS) + +/* + * waiters (aka. ongoing_packs): # to unlock the page + * sub-index: 0 - for partial page, >= 1 full page sub-index + */ +typedef atomic_t z_erofs_onlinepage_t; + +/* type punning */ +union z_erofs_onlinepage_converter { + z_erofs_onlinepage_t *o; + unsigned long *v; +}; + +static inline unsigned z_erofs_onlinepage_index(struct page *page) +{ + union z_erofs_onlinepage_converter u; + + BUG_ON(!PagePrivate(page)); + u.v = &page_private(page); + + return atomic_read(u.o) >> Z_EROFS_ONLINEPAGE_INDEX_SHIFT; +} + +static inline void z_erofs_onlinepage_init(struct page *page) +{ + union { + z_erofs_onlinepage_t o; + unsigned long v; + /* keep from being unlocked in advance */ + } u = { .o = ATOMIC_INIT(1) }; + + set_page_private(page, u.v); + smp_wmb(); + SetPagePrivate(page); +} + +static inline void z_erofs_onlinepage_fixup(struct page *page, + uintptr_t index, bool down) +{ + unsigned long *p, o, v, id; +repeat: + p = &page_private(page); + o = READ_ONCE(*p); + + id = o >> Z_EROFS_ONLINEPAGE_INDEX_SHIFT; + if (id) { + if (!index) + return; + + BUG_ON(id != index); + } + + v = (index << Z_EROFS_ONLINEPAGE_INDEX_SHIFT) | + ((o & Z_EROFS_ONLINEPAGE_COUNT_MASK) + (unsigned)down); + if (cmpxchg(p, o, v) != o) + goto repeat; +} + +static inline void z_erofs_onlinepage_endio(struct page *page) +{ + union z_erofs_onlinepage_converter u; + unsigned v; + + BUG_ON(!PagePrivate(page)); + u.v = &page_private(page); + + v = atomic_dec_return(u.o); + if (!(v & Z_EROFS_ONLINEPAGE_COUNT_MASK)) { + ClearPagePrivate(page); + if (!PageError(page)) + SetPageUptodate(page); + unlock_page(page); + } + + debugln("%s, page %p value %x", __func__, page, atomic_read(u.o)); +} + +#define Z_EROFS_VLE_VMAP_ONSTACK_PAGES \ + min_t(unsigned int, THREAD_SIZE / 8 / sizeof(struct page *), 96U) +#define Z_EROFS_VLE_VMAP_GLOBAL_PAGES 2048 + +/* unzip_vle_lz4.c */ +extern int z_erofs_vle_plain_copy(struct page **compressed_pages, + unsigned clusterpages, struct page **pages, + unsigned nr_pages, unsigned short pageofs); + +extern int z_erofs_vle_unzip_fast_percpu(struct page **compressed_pages, + unsigned clusterpages, struct page **pages, + unsigned outlen, unsigned short pageofs, + void (*endio)(struct page *)); + +extern int z_erofs_vle_unzip_vmap(struct page **compressed_pages, + unsigned clusterpages, void *vaddr, unsigned llen, + unsigned short pageofs, bool overlapped); + +#endif + |