[PATCH 2/5] erofs: record `pclustersize` in bytes instead of pages
Gao Xiang
hsiangkao at linux.alibaba.com
Wed Dec 6 20:10:54 AEDT 2023
Currently, compressed sizes are recorded in pages using `pclusterpages`,
However, for tailpacking pclusters, `tailpacking_size` is used instead.
This approach doesn't work when dealing with sub-page blocks. To address
this, let's switch them to the unified `pclustersize` in bytes.
Signed-off-by: Gao Xiang <hsiangkao at linux.alibaba.com>
---
fs/erofs/zdata.c | 64 ++++++++++++++++++++----------------------------
1 file changed, 26 insertions(+), 38 deletions(-)
diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c
index 421c0a88a0ca..d02989466711 100644
--- a/fs/erofs/zdata.c
+++ b/fs/erofs/zdata.c
@@ -56,6 +56,9 @@ struct z_erofs_pcluster {
/* L: total number of bvecs */
unsigned int vcnt;
+ /* I: pcluster size (compressed size) in bytes */
+ unsigned int pclustersize;
+
/* I: page offset of start position of decompression */
unsigned short pageofs_out;
@@ -70,14 +73,6 @@ struct z_erofs_pcluster {
struct rcu_head rcu;
};
- union {
- /* I: physical cluster size in pages */
- unsigned short pclusterpages;
-
- /* I: tailpacking inline compressed size */
- unsigned short tailpacking_size;
- };
-
/* I: compression algorithm format */
unsigned char algorithmformat;
@@ -115,9 +110,7 @@ static inline bool z_erofs_is_inline_pcluster(struct z_erofs_pcluster *pcl)
static inline unsigned int z_erofs_pclusterpages(struct z_erofs_pcluster *pcl)
{
- if (z_erofs_is_inline_pcluster(pcl))
- return 1;
- return pcl->pclusterpages;
+ return PAGE_ALIGN(pcl->pclustersize) >> PAGE_SHIFT;
}
/*
@@ -298,12 +291,12 @@ static int z_erofs_create_pcluster_pool(void)
return 0;
}
-static struct z_erofs_pcluster *z_erofs_alloc_pcluster(unsigned int nrpages)
+static struct z_erofs_pcluster *z_erofs_alloc_pcluster(unsigned int size)
{
- int i;
+ unsigned int nrpages = PAGE_ALIGN(size) >> PAGE_SHIFT;
+ struct z_erofs_pcluster_slab *pcs = pcluster_pool;
- for (i = 0; i < ARRAY_SIZE(pcluster_pool); ++i) {
- struct z_erofs_pcluster_slab *pcs = pcluster_pool + i;
+ for (; pcs < pcluster_pool + ARRAY_SIZE(pcluster_pool); ++pcs) {
struct z_erofs_pcluster *pcl;
if (nrpages > pcs->maxpages)
@@ -312,7 +305,7 @@ static struct z_erofs_pcluster *z_erofs_alloc_pcluster(unsigned int nrpages)
pcl = kmem_cache_zalloc(pcs->slab, GFP_NOFS);
if (!pcl)
return ERR_PTR(-ENOMEM);
- pcl->pclusterpages = nrpages;
+ pcl->pclustersize = size;
return pcl;
}
return ERR_PTR(-EINVAL);
@@ -559,6 +552,7 @@ static void z_erofs_bind_cache(struct z_erofs_decompress_frontend *fe)
{
struct address_space *mc = MNGD_MAPPING(EROFS_I_SB(fe->inode));
struct z_erofs_pcluster *pcl = fe->pcl;
+ unsigned int pclusterpages = z_erofs_pclusterpages(pcl);
bool shouldalloc = z_erofs_should_alloc_cache(fe);
bool standalone = true;
/*
@@ -572,10 +566,9 @@ static void z_erofs_bind_cache(struct z_erofs_decompress_frontend *fe)
if (fe->mode < Z_EROFS_PCLUSTER_FOLLOWED)
return;
- for (i = 0; i < pcl->pclusterpages; ++i) {
- struct page *page;
+ for (i = 0; i < pclusterpages; ++i) {
+ struct page *page, *newpage;
void *t; /* mark pages just found for debugging */
- struct page *newpage = NULL;
/* the compressed page was loaded before */
if (READ_ONCE(pcl->compressed_bvecs[i].page))
@@ -585,6 +578,7 @@ static void z_erofs_bind_cache(struct z_erofs_decompress_frontend *fe)
if (page) {
t = (void *)((unsigned long)page | 1);
+ newpage = NULL;
} else {
/* I/O is needed, no possible to decompress directly */
standalone = false;
@@ -592,9 +586,8 @@ static void z_erofs_bind_cache(struct z_erofs_decompress_frontend *fe)
continue;
/*
- * try to use cached I/O if page allocation
- * succeeds or fallback to in-place I/O instead
- * to avoid any direct reclaim.
+ * Try cached I/O if allocation succeeds or fallback to
+ * in-place I/O instead to avoid any direct reclaim.
*/
newpage = erofs_allocpage(&fe->pagepool, gfp);
if (!newpage)
@@ -626,6 +619,7 @@ int erofs_try_to_free_all_cached_pages(struct erofs_sb_info *sbi,
{
struct z_erofs_pcluster *const pcl =
container_of(grp, struct z_erofs_pcluster, obj);
+ unsigned int pclusterpages = z_erofs_pclusterpages(pcl);
int i;
DBG_BUGON(z_erofs_is_inline_pcluster(pcl));
@@ -633,7 +627,7 @@ int erofs_try_to_free_all_cached_pages(struct erofs_sb_info *sbi,
* refcount of workgroup is now freezed as 0,
* therefore no need to worry about available decompression users.
*/
- for (i = 0; i < pcl->pclusterpages; ++i) {
+ for (i = 0; i < pclusterpages; ++i) {
struct page *page = pcl->compressed_bvecs[i].page;
if (!page)
@@ -657,6 +651,7 @@ int erofs_try_to_free_all_cached_pages(struct erofs_sb_info *sbi,
static bool z_erofs_cache_release_folio(struct folio *folio, gfp_t gfp)
{
struct z_erofs_pcluster *pcl = folio_get_private(folio);
+ unsigned int pclusterpages = z_erofs_pclusterpages(pcl);
bool ret;
int i;
@@ -669,7 +664,7 @@ static bool z_erofs_cache_release_folio(struct folio *folio, gfp_t gfp)
goto out;
DBG_BUGON(z_erofs_is_inline_pcluster(pcl));
- for (i = 0; i < pcl->pclusterpages; ++i) {
+ for (i = 0; i < pclusterpages; ++i) {
if (pcl->compressed_bvecs[i].page == &folio->page) {
WRITE_ONCE(pcl->compressed_bvecs[i].page, NULL);
ret = true;
@@ -778,20 +773,20 @@ static void z_erofs_try_to_claim_pcluster(struct z_erofs_decompress_frontend *f)
static int z_erofs_register_pcluster(struct z_erofs_decompress_frontend *fe)
{
struct erofs_map_blocks *map = &fe->map;
+ struct super_block *sb = fe->inode->i_sb;
bool ztailpacking = map->m_flags & EROFS_MAP_META;
struct z_erofs_pcluster *pcl;
struct erofs_workgroup *grp;
int err;
if (!(map->m_flags & EROFS_MAP_ENCODED) ||
- (!ztailpacking && !(map->m_pa >> PAGE_SHIFT))) {
+ (!ztailpacking && !erofs_blknr(sb, map->m_pa))) {
DBG_BUGON(1);
return -EFSCORRUPTED;
}
/* no available pcluster, let's allocate one */
- pcl = z_erofs_alloc_pcluster(ztailpacking ? 1 :
- map->m_plen >> PAGE_SHIFT);
+ pcl = z_erofs_alloc_pcluster(map->m_plen);
if (IS_ERR(pcl))
return PTR_ERR(pcl);
@@ -816,9 +811,8 @@ static int z_erofs_register_pcluster(struct z_erofs_decompress_frontend *fe)
if (ztailpacking) {
pcl->obj.index = 0; /* which indicates ztailpacking */
pcl->pageofs_in = erofs_blkoff(fe->inode->i_sb, map->m_pa);
- pcl->tailpacking_size = map->m_plen;
} else {
- pcl->obj.index = map->m_pa >> PAGE_SHIFT;
+ pcl->obj.index = erofs_blknr(sb, map->m_pa);
grp = erofs_insert_workgroup(fe->inode->i_sb, &pcl->obj);
if (IS_ERR(grp)) {
@@ -1244,8 +1238,7 @@ static int z_erofs_decompress_pcluster(struct z_erofs_decompress_backend *be,
unsigned int pclusterpages = z_erofs_pclusterpages(pcl);
const struct z_erofs_decompressor *decompressor =
&erofs_decompressors[pcl->algorithmformat];
- unsigned int i, inputsize;
- int err2;
+ int i, err2;
struct page *page;
bool overlapped;
@@ -1282,18 +1275,13 @@ static int z_erofs_decompress_pcluster(struct z_erofs_decompress_backend *be,
if (err)
goto out;
- if (z_erofs_is_inline_pcluster(pcl))
- inputsize = pcl->tailpacking_size;
- else
- inputsize = pclusterpages * PAGE_SIZE;
-
err = decompressor->decompress(&(struct z_erofs_decompress_req) {
.sb = be->sb,
.in = be->compressed_pages,
.out = be->decompressed_pages,
.pageofs_in = pcl->pageofs_in,
.pageofs_out = pcl->pageofs_out,
- .inputsize = inputsize,
+ .inputsize = pcl->pclustersize,
.outputsize = pcl->length,
.alg = pcl->algorithmformat,
.inplace_io = overlapped,
@@ -1668,7 +1656,7 @@ static void z_erofs_submit_queue(struct z_erofs_decompress_frontend *f,
(void)erofs_map_dev(sb, &mdev);
cur = mdev.m_pa;
- end = cur + pcl->pclusterpages << PAGE_SHIFT;
+ end = cur + pcl->pclustersize;
do {
z_erofs_fill_bio_vec(&bvec, f, pcl, i++, mc);
if (!bvec.bv_page)
--
2.39.3
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