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Diffstat (limited to 'fs/erofs/zmap.c')
-rw-r--r--fs/erofs/zmap.c125
1 files changed, 52 insertions, 73 deletions
diff --git a/fs/erofs/zmap.c b/fs/erofs/zmap.c
index 4535f2f0a014..689437e99a5a 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)
{
@@ -311,27 +294,23 @@ err_bogus:
static int z_erofs_get_extent_compressedlen(struct z_erofs_maprecorder *m,
unsigned int initial_lcn)
{
- struct super_block *sb = m->inode->i_sb;
- struct erofs_inode *const vi = EROFS_I(m->inode);
- struct erofs_map_blocks *const map = m->map;
- const unsigned int lclusterbits = vi->z_logical_clusterbits;
- unsigned long lcn;
+ struct inode *inode = m->inode;
+ struct super_block *sb = inode->i_sb;
+ struct erofs_inode *vi = EROFS_I(inode);
+ bool bigpcl1 = vi->z_advise & Z_EROFS_ADVISE_BIG_PCLUSTER_1;
+ bool bigpcl2 = vi->z_advise & Z_EROFS_ADVISE_BIG_PCLUSTER_2;
+ unsigned long lcn = m->lcn + 1;
int err;
- DBG_BUGON(m->type != Z_EROFS_LCLUSTER_TYPE_PLAIN &&
- m->type != Z_EROFS_LCLUSTER_TYPE_HEAD1 &&
- m->type != Z_EROFS_LCLUSTER_TYPE_HEAD2);
+ DBG_BUGON(m->type == Z_EROFS_LCLUSTER_TYPE_NONHEAD);
DBG_BUGON(m->type != m->headtype);
- if (m->headtype == Z_EROFS_LCLUSTER_TYPE_PLAIN ||
- ((m->headtype == Z_EROFS_LCLUSTER_TYPE_HEAD1) &&
- !(vi->z_advise & Z_EROFS_ADVISE_BIG_PCLUSTER_1)) ||
- ((m->headtype == Z_EROFS_LCLUSTER_TYPE_HEAD2) &&
- !(vi->z_advise & Z_EROFS_ADVISE_BIG_PCLUSTER_2))) {
- map->m_plen = 1ULL << lclusterbits;
- return 0;
- }
- lcn = m->lcn + 1;
+ if ((m->headtype == Z_EROFS_LCLUSTER_TYPE_HEAD1 && !bigpcl1) ||
+ ((m->headtype == Z_EROFS_LCLUSTER_TYPE_PLAIN ||
+ m->headtype == Z_EROFS_LCLUSTER_TYPE_HEAD2) && !bigpcl2) ||
+ (lcn << vi->z_logical_clusterbits) >= inode->i_size)
+ m->compressedblks = 1;
+
if (m->compressedblks)
goto out;
@@ -356,9 +335,9 @@ static int z_erofs_get_extent_compressedlen(struct z_erofs_maprecorder *m,
case Z_EROFS_LCLUSTER_TYPE_HEAD2:
/*
* if the 1st NONHEAD lcluster is actually PLAIN or HEAD type
- * rather than CBLKCNT, it's a 1 lcluster-sized pcluster.
+ * rather than CBLKCNT, it's a 1 block-sized pcluster.
*/
- m->compressedblks = 1 << (lclusterbits - sb->s_blocksize_bits);
+ m->compressedblks = 1;
break;
case Z_EROFS_LCLUSTER_TYPE_NONHEAD:
if (m->delta[0] != 1)
@@ -373,7 +352,7 @@ static int z_erofs_get_extent_compressedlen(struct z_erofs_maprecorder *m,
return -EFSCORRUPTED;
}
out:
- map->m_plen = erofs_pos(sb, m->compressedblks);
+ m->map->m_plen = erofs_pos(sb, m->compressedblks);
return 0;
err_bonus_cblkcnt:
erofs_err(sb, "bogus CBLKCNT @ lcn %lu of nid %llu", lcn, vi->nid);
generated by cgit v1.2.3 (git 2.46.0) at 2025-08-25 21:43:26 +0000