From: Gao Xiang hsiangkao@linux.alibaba.com
[ Upstream commit 2a810ea79cd7a6d5f134ea69ca2ba726e600cbc4 ]
- Get rid of unpack_compacted_index() and fold it into z_erofs_load_compact_lcluster();
- Avoid a goto.
Reviewed-by: Chao Yu chao@kernel.org Signed-off-by: Gao Xiang hsiangkao@linux.alibaba.com Link: https://lore.kernel.org/r/20250114034429.431408-1-hsiangkao@linux.alibaba.co... Stable-dep-of: b44686c8391b ("erofs: fix large fragment handling") Signed-off-by: Sasha Levin sashal@kernel.org --- fs/erofs/zmap.c | 89 ++++++++++++++++++++----------------------------- 1 file changed, 36 insertions(+), 53 deletions(-)
diff --git a/fs/erofs/zmap.c b/fs/erofs/zmap.c index 4535f2f0a0147..b9e35089c9b8d 100644 --- a/fs/erofs/zmap.c +++ b/fs/erofs/zmap.c @@ -97,17 +97,48 @@ static int get_compacted_la_distance(unsigned int lobits, return d1; }
-static int unpack_compacted_index(struct z_erofs_maprecorder *m, - unsigned int amortizedshift, - erofs_off_t pos, bool lookahead) +static int z_erofs_load_compact_lcluster(struct z_erofs_maprecorder *m, + unsigned long lcn, bool lookahead) { - struct erofs_inode *const vi = EROFS_I(m->inode); + struct inode *const inode = m->inode; + struct erofs_inode *const vi = EROFS_I(inode); + const erofs_off_t ebase = sizeof(struct z_erofs_map_header) + + ALIGN(erofs_iloc(inode) + vi->inode_isize + vi->xattr_isize, 8); const unsigned int lclusterbits = vi->z_logical_clusterbits; + const unsigned int totalidx = erofs_iblks(inode); + unsigned int compacted_4b_initial, compacted_2b, amortizedshift; unsigned int vcnt, lo, lobits, encodebits, nblk, bytes; - bool big_pcluster; + bool big_pcluster = vi->z_advise & Z_EROFS_ADVISE_BIG_PCLUSTER_1; + erofs_off_t pos; u8 *in, type; int i;
+ if (lcn >= totalidx || lclusterbits > 14) + return -EINVAL; + + m->lcn = lcn; + /* used to align to 32-byte (compacted_2b) alignment */ + compacted_4b_initial = ((32 - ebase % 32) / 4) & 7; + compacted_2b = 0; + if ((vi->z_advise & Z_EROFS_ADVISE_COMPACTED_2B) && + compacted_4b_initial < totalidx) + compacted_2b = rounddown(totalidx - compacted_4b_initial, 16); + + pos = ebase; + amortizedshift = 2; /* compact_4b */ + if (lcn >= compacted_4b_initial) { + pos += compacted_4b_initial * 4; + lcn -= compacted_4b_initial; + if (lcn < compacted_2b) { + amortizedshift = 1; + } else { + pos += compacted_2b * 2; + lcn -= compacted_2b; + } + } + pos += lcn * (1 << amortizedshift); + + /* figure out the lcluster count in this pack */ if (1 << amortizedshift == 4 && lclusterbits <= 14) vcnt = 2; else if (1 << amortizedshift == 2 && lclusterbits <= 12) @@ -122,7 +153,6 @@ static int unpack_compacted_index(struct z_erofs_maprecorder *m, /* it doesn't equal to round_up(..) */ m->nextpackoff = round_down(pos, vcnt << amortizedshift) + (vcnt << amortizedshift); - big_pcluster = vi->z_advise & Z_EROFS_ADVISE_BIG_PCLUSTER_1; lobits = max(lclusterbits, ilog2(Z_EROFS_LI_D0_CBLKCNT) + 1U); encodebits = ((vcnt << amortizedshift) - sizeof(__le32)) * 8 / vcnt; bytes = pos & ((vcnt << amortizedshift) - 1); @@ -207,53 +237,6 @@ static int unpack_compacted_index(struct z_erofs_maprecorder *m, return 0; }
-static int z_erofs_load_compact_lcluster(struct z_erofs_maprecorder *m, - unsigned long lcn, bool lookahead) -{ - struct inode *const inode = m->inode; - struct erofs_inode *const vi = EROFS_I(inode); - const erofs_off_t ebase = sizeof(struct z_erofs_map_header) + - ALIGN(erofs_iloc(inode) + vi->inode_isize + vi->xattr_isize, 8); - unsigned int totalidx = erofs_iblks(inode); - unsigned int compacted_4b_initial, compacted_2b; - unsigned int amortizedshift; - erofs_off_t pos; - - if (lcn >= totalidx || vi->z_logical_clusterbits > 14) - return -EINVAL; - - m->lcn = lcn; - /* used to align to 32-byte (compacted_2b) alignment */ - compacted_4b_initial = (32 - ebase % 32) / 4; - if (compacted_4b_initial == 32 / 4) - compacted_4b_initial = 0; - - if ((vi->z_advise & Z_EROFS_ADVISE_COMPACTED_2B) && - compacted_4b_initial < totalidx) - compacted_2b = rounddown(totalidx - compacted_4b_initial, 16); - else - compacted_2b = 0; - - pos = ebase; - if (lcn < compacted_4b_initial) { - amortizedshift = 2; - goto out; - } - pos += compacted_4b_initial * 4; - lcn -= compacted_4b_initial; - - if (lcn < compacted_2b) { - amortizedshift = 1; - goto out; - } - pos += compacted_2b * 2; - lcn -= compacted_2b; - amortizedshift = 2; -out: - pos += lcn * (1 << amortizedshift); - return unpack_compacted_index(m, amortizedshift, pos, lookahead); -} - static int z_erofs_load_lcluster_from_disk(struct z_erofs_maprecorder *m, unsigned int lcn, bool lookahead) {