[PATCH 05/16] erofs: drop the old pagevec approach
Gao Xiang
hsiangkao at linux.alibaba.com
Thu Jul 14 23:20:40 AEST 2022
Remove the old pagevec approach but keep z_erofs_page_type for now.
It will be reworked in the following commits as well.
Also rename Z_EROFS_NR_INLINE_PAGEVECS as Z_EROFS_INLINE_BVECS with
the new value 2 since it's actually enough to bootstrap.
Signed-off-by: Gao Xiang <hsiangkao at linux.alibaba.com>
---
fs/erofs/zdata.c | 17 +++--
fs/erofs/zdata.h | 9 +--
fs/erofs/zpvec.h | 159 -----------------------------------------------
3 files changed, 16 insertions(+), 169 deletions(-)
delete mode 100644 fs/erofs/zpvec.h
diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c
index f52c54058f31..e96704db106e 100644
--- a/fs/erofs/zdata.c
+++ b/fs/erofs/zdata.c
@@ -27,6 +27,17 @@ static struct z_erofs_pcluster_slab pcluster_pool[] __read_mostly = {
_PCLP(Z_EROFS_PCLUSTER_MAX_PAGES)
};
+/* page type in pagevec for decompress subsystem */
+enum z_erofs_page_type {
+ /* including Z_EROFS_VLE_PAGE_TAIL_EXCLUSIVE */
+ Z_EROFS_PAGE_TYPE_EXCLUSIVE,
+
+ Z_EROFS_VLE_PAGE_TYPE_TAIL_SHARED,
+
+ Z_EROFS_VLE_PAGE_TYPE_HEAD,
+ Z_EROFS_VLE_PAGE_TYPE_MAX
+};
+
struct z_erofs_bvec_iter {
struct page *bvpage;
struct z_erofs_bvset *bvset;
@@ -273,7 +284,6 @@ struct z_erofs_decompress_frontend {
struct inode *const inode;
struct erofs_map_blocks map;
struct z_erofs_bvec_iter biter;
- struct z_erofs_pagevec_ctor vector;
struct page *candidate_bvpage;
struct z_erofs_pcluster *pcl, *tailpcl;
@@ -636,7 +646,7 @@ static int z_erofs_collector_begin(struct z_erofs_decompress_frontend *fe)
return ret;
}
z_erofs_bvec_iter_begin(&fe->biter, &fe->pcl->bvset,
- Z_EROFS_NR_INLINE_PAGEVECS, fe->pcl->vcnt);
+ Z_EROFS_INLINE_BVECS, fe->pcl->vcnt);
/* since file-backed online pages are traversed in reverse order */
fe->icpage_ptr = fe->pcl->compressed_pages +
z_erofs_pclusterpages(fe->pcl);
@@ -871,8 +881,7 @@ static int z_erofs_parse_out_bvecs(struct z_erofs_pcluster *pcl,
struct page *old_bvpage;
int i, err = 0;
- z_erofs_bvec_iter_begin(&biter, &pcl->bvset,
- Z_EROFS_NR_INLINE_PAGEVECS, 0);
+ z_erofs_bvec_iter_begin(&biter, &pcl->bvset, Z_EROFS_INLINE_BVECS, 0);
for (i = 0; i < pcl->vcnt; ++i) {
struct z_erofs_bvec bvec;
unsigned int pagenr;
diff --git a/fs/erofs/zdata.h b/fs/erofs/zdata.h
index d03e333e4fde..a755c5a44d87 100644
--- a/fs/erofs/zdata.h
+++ b/fs/erofs/zdata.h
@@ -7,10 +7,10 @@
#define __EROFS_FS_ZDATA_H
#include "internal.h"
-#include "zpvec.h"
+#include "tagptr.h"
#define Z_EROFS_PCLUSTER_MAX_PAGES (Z_EROFS_PCLUSTER_MAX_SIZE / PAGE_SIZE)
-#define Z_EROFS_NR_INLINE_PAGEVECS 3
+#define Z_EROFS_INLINE_BVECS 2
#define Z_EROFS_PCLUSTER_FULL_LENGTH 0x00000001
#define Z_EROFS_PCLUSTER_LENGTH_BIT 1
@@ -34,7 +34,7 @@ struct name { \
struct z_erofs_bvec bvec[total]; \
};
__Z_EROFS_BVSET(z_erofs_bvset,)
-__Z_EROFS_BVSET(z_erofs_bvset_inline, Z_EROFS_NR_INLINE_PAGEVECS)
+__Z_EROFS_BVSET(z_erofs_bvset_inline, Z_EROFS_INLINE_BVECS)
/*
* Structure fields follow one of the following exclusion rules.
@@ -69,9 +69,6 @@ struct z_erofs_pcluster {
unsigned short nr_pages;
union {
- /* L: inline a certain number of pagevecs for bootstrap */
- erofs_vtptr_t pagevec[Z_EROFS_NR_INLINE_PAGEVECS];
-
/* L: inline a certain number of bvec for bootstrap */
struct z_erofs_bvset_inline bvset;
diff --git a/fs/erofs/zpvec.h b/fs/erofs/zpvec.h
deleted file mode 100644
index b05464f4a808..000000000000
--- a/fs/erofs/zpvec.h
+++ /dev/null
@@ -1,159 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0-only */
-/*
- * Copyright (C) 2018 HUAWEI, Inc.
- * https://www.huawei.com/
- */
-#ifndef __EROFS_FS_ZPVEC_H
-#define __EROFS_FS_ZPVEC_H
-
-#include "tagptr.h"
-
-/* page type in pagevec for decompress subsystem */
-enum z_erofs_page_type {
- /* including Z_EROFS_VLE_PAGE_TAIL_EXCLUSIVE */
- Z_EROFS_PAGE_TYPE_EXCLUSIVE,
-
- Z_EROFS_VLE_PAGE_TYPE_TAIL_SHARED,
-
- Z_EROFS_VLE_PAGE_TYPE_HEAD,
- Z_EROFS_VLE_PAGE_TYPE_MAX
-};
-
-extern void __compiletime_error("Z_EROFS_PAGE_TYPE_EXCLUSIVE != 0")
- __bad_page_type_exclusive(void);
-
-/* pagevec tagged pointer */
-typedef tagptr2_t erofs_vtptr_t;
-
-/* pagevec collector */
-struct z_erofs_pagevec_ctor {
- struct page *curr, *next;
- erofs_vtptr_t *pages;
-
- unsigned int nr, index;
-};
-
-static inline void z_erofs_pagevec_ctor_exit(struct z_erofs_pagevec_ctor *ctor,
- bool atomic)
-{
- if (!ctor->curr)
- return;
-
- if (atomic)
- kunmap_atomic(ctor->pages);
- else
- kunmap(ctor->curr);
-}
-
-static inline struct page *
-z_erofs_pagevec_ctor_next_page(struct z_erofs_pagevec_ctor *ctor,
- unsigned int nr)
-{
- unsigned int index;
-
- /* keep away from occupied pages */
- if (ctor->next)
- return ctor->next;
-
- for (index = 0; index < nr; ++index) {
- const erofs_vtptr_t t = ctor->pages[index];
- const unsigned int tags = tagptr_unfold_tags(t);
-
- if (tags == Z_EROFS_PAGE_TYPE_EXCLUSIVE)
- return tagptr_unfold_ptr(t);
- }
- DBG_BUGON(nr >= ctor->nr);
- return NULL;
-}
-
-static inline void
-z_erofs_pagevec_ctor_pagedown(struct z_erofs_pagevec_ctor *ctor,
- bool atomic)
-{
- struct page *next = z_erofs_pagevec_ctor_next_page(ctor, ctor->nr);
-
- z_erofs_pagevec_ctor_exit(ctor, atomic);
-
- ctor->curr = next;
- ctor->next = NULL;
- ctor->pages = atomic ?
- kmap_atomic(ctor->curr) : kmap(ctor->curr);
-
- ctor->nr = PAGE_SIZE / sizeof(struct page *);
- ctor->index = 0;
-}
-
-static inline void z_erofs_pagevec_ctor_init(struct z_erofs_pagevec_ctor *ctor,
- unsigned int nr,
- erofs_vtptr_t *pages,
- unsigned int i)
-{
- ctor->nr = nr;
- ctor->curr = ctor->next = NULL;
- ctor->pages = pages;
-
- if (i >= nr) {
- i -= nr;
- z_erofs_pagevec_ctor_pagedown(ctor, false);
- while (i > ctor->nr) {
- i -= ctor->nr;
- z_erofs_pagevec_ctor_pagedown(ctor, false);
- }
- }
- ctor->next = z_erofs_pagevec_ctor_next_page(ctor, i);
- ctor->index = i;
-}
-
-static inline bool z_erofs_pagevec_enqueue(struct z_erofs_pagevec_ctor *ctor,
- struct page *page,
- enum z_erofs_page_type type,
- bool pvec_safereuse)
-{
- if (!ctor->next) {
- /* some pages cannot be reused as pvec safely without I/O */
- if (type == Z_EROFS_PAGE_TYPE_EXCLUSIVE && !pvec_safereuse)
- type = Z_EROFS_VLE_PAGE_TYPE_TAIL_SHARED;
-
- if (type != Z_EROFS_PAGE_TYPE_EXCLUSIVE &&
- ctor->index + 1 == ctor->nr)
- return false;
- }
-
- if (ctor->index >= ctor->nr)
- z_erofs_pagevec_ctor_pagedown(ctor, false);
-
- /* exclusive page type must be 0 */
- if (Z_EROFS_PAGE_TYPE_EXCLUSIVE != (uintptr_t)NULL)
- __bad_page_type_exclusive();
-
- /* should remind that collector->next never equal to 1, 2 */
- if (type == (uintptr_t)ctor->next) {
- ctor->next = page;
- }
- ctor->pages[ctor->index++] = tagptr_fold(erofs_vtptr_t, page, type);
- return true;
-}
-
-static inline struct page *
-z_erofs_pagevec_dequeue(struct z_erofs_pagevec_ctor *ctor,
- enum z_erofs_page_type *type)
-{
- erofs_vtptr_t t;
-
- if (ctor->index >= ctor->nr) {
- DBG_BUGON(!ctor->next);
- z_erofs_pagevec_ctor_pagedown(ctor, true);
- }
-
- t = ctor->pages[ctor->index];
-
- *type = tagptr_unfold_tags(t);
-
- /* should remind that collector->next never equal to 1, 2 */
- if (*type == (uintptr_t)ctor->next)
- ctor->next = tagptr_unfold_ptr(t);
-
- ctor->pages[ctor->index++] = tagptr_fold(erofs_vtptr_t, NULL, 0);
- return tagptr_unfold_ptr(t);
-}
-#endif
--
2.24.4
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