FAILED: patch "[PATCH] erofs: fix large fragment handling" failed to apply to 6.12-stable tree

FAILED: patch "[PATCH] erofs: fix large fragment handling" failed to apply to 6.12-stable tree

[gregkh]

The patch below does not apply to the 6.12-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.12.y
git checkout FETCH_HEAD
git cherry-pick -x b44686c8391b427fb1c85a31c35077e6947c6d90
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2025071422-preview-germinate-b2de@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From b44686c8391b427fb1c85a31c35077e6947c6d90 Mon Sep 17 00:00:00 2001
From: Gao Xiang <xiang@kernel.org>
Date: Sat, 12 Jul 2025 03:58:26 +0800
Subject: [PATCH] erofs: fix large fragment handling

Fragments aren't limited by Z_EROFS_PCLUSTER_MAX_DSIZE. However, if
a fragment's logical length is larger than Z_EROFS_PCLUSTER_MAX_DSIZE
but the fragment is not the whole inode, it currently returns
-EOPNOTSUPP because m_flags has the wrong EROFS_MAP_ENCODED flag set.
It is not intended by design but should be rare, as it can only be
reproduced by mkfs with `-Eall-fragments` in a specific case.

Let's normalize fragment m_flags using the new EROFS_MAP_FRAGMENT.

Reported-by: Axel Fontaine <axel@axelfontaine.com>
Closes: https://github.com/erofs/erofs-utils/issues/23
Fixes: 7c3ca1838a78 ("erofs: restrict pcluster size limitations")
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20250711195826.3601157-1-hsiangkao@linux.alibaba.com

diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h
index 0d19bde8c094..06b867d2fc3b 100644
--- a/fs/erofs/internal.h
+++ b/fs/erofs/internal.h
@@ -315,10 +315,12 @@ static inline struct folio *erofs_grab_folio_nowait(struct address_space *as,
 /* The length of extent is full */
 #define EROFS_MAP_FULL_MAPPED	0x0008
 /* Located in the special packed inode */
-#define EROFS_MAP_FRAGMENT	0x0010
+#define __EROFS_MAP_FRAGMENT	0x0010
 /* The extent refers to partial decompressed data */
 #define EROFS_MAP_PARTIAL_REF	0x0020
 
+#define EROFS_MAP_FRAGMENT	(EROFS_MAP_MAPPED | __EROFS_MAP_FRAGMENT)
+
 struct erofs_map_blocks {
 	struct erofs_buf buf;
 
diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c
index 32e3905e75fe..e3f28a1bb945 100644
--- a/fs/erofs/zdata.c
+++ b/fs/erofs/zdata.c
@@ -1034,7 +1034,7 @@ static int z_erofs_scan_folio(struct z_erofs_frontend *f,
 		if (!(map->m_flags & EROFS_MAP_MAPPED)) {
 			folio_zero_segment(folio, cur, end);
 			tight = false;
-		} else if (map->m_flags & EROFS_MAP_FRAGMENT) {
+		} else if (map->m_flags & __EROFS_MAP_FRAGMENT) {
 			erofs_off_t fpos = offset + cur - map->m_la;
 
 			err = z_erofs_read_fragment(inode->i_sb, folio, cur,
diff --git a/fs/erofs/zmap.c b/fs/erofs/zmap.c
index 0bebc6e3a4d7..f1a15ff22147 100644
--- a/fs/erofs/zmap.c
+++ b/fs/erofs/zmap.c
@@ -413,8 +413,7 @@ static int z_erofs_map_blocks_fo(struct inode *inode,
 	    !vi->z_tailextent_headlcn) {
 		map->m_la = 0;
 		map->m_llen = inode->i_size;
-		map->m_flags = EROFS_MAP_MAPPED |
-			EROFS_MAP_FULL_MAPPED | EROFS_MAP_FRAGMENT;
+		map->m_flags = EROFS_MAP_FRAGMENT;
 		return 0;
 	}
 	initial_lcn = ofs >> lclusterbits;
@@ -489,7 +488,7 @@ static int z_erofs_map_blocks_fo(struct inode *inode,
 			goto unmap_out;
 		}
 	} else if (fragment && m.lcn == vi->z_tailextent_headlcn) {
-		map->m_flags |= EROFS_MAP_FRAGMENT;
+		map->m_flags = EROFS_MAP_FRAGMENT;
 	} else {
 		map->m_pa = erofs_pos(sb, m.pblk);
 		err = z_erofs_get_extent_compressedlen(&m, initial_lcn);
@@ -617,7 +616,7 @@ static int z_erofs_map_blocks_ext(struct inode *inode,
 	if (lstart < lend) {
 		map->m_la = lstart;
 		if (last && (vi->z_advise & Z_EROFS_ADVISE_FRAGMENT_PCLUSTER)) {
-			map->m_flags |= EROFS_MAP_MAPPED | EROFS_MAP_FRAGMENT;
+			map->m_flags = EROFS_MAP_FRAGMENT;
 			vi->z_fragmentoff = map->m_plen;
 			if (recsz > offsetof(struct z_erofs_extent, pstart_lo))
 				vi->z_fragmentoff |= map->m_pa << 32;
@@ -797,7 +796,7 @@ static int z_erofs_iomap_begin_report(struct inode *inode, loff_t offset,
 	iomap->length = map.m_llen;
 	if (map.m_flags & EROFS_MAP_MAPPED) {
 		iomap->type = IOMAP_MAPPED;
-		iomap->addr = map.m_flags & EROFS_MAP_FRAGMENT ?
+		iomap->addr = map.m_flags & __EROFS_MAP_FRAGMENT ?
 			      IOMAP_NULL_ADDR : map.m_pa;
 	} else {
 		iomap->type = IOMAP_HOLE;

[PATCH 6.12.y 1/6] erofs: simplify z_erofs_load_compact_lcluster()

[Sasha Levin]

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.com
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)
 {
-- 
2.39.5

[PATCH 6.12.y 2/6] erofs: refine z_erofs_get_extent_compressedlen()

[Sasha Levin]

From: Gao Xiang <hsiangkao@linux.alibaba.com>

[ Upstream commit 8f9530aeeb4f756bdfa70510b40e5d28ea3c742e ]

 - Set `compressedblks = 1` directly for non-bigpcluster cases.  This
   simplifies the logic a bit since lcluster sizes larger than one block
   are unsupported and the details remain unclear.

 - For Z_EROFS_LCLUSTER_TYPE_PLAIN pclusters, avoid assuming
   `compressedblks = 1` by default.  Instead, check if
   Z_EROFS_ADVISE_BIG_PCLUSTER_2 is set.

It basically has no impact to existing valid images, but it's useful to
find the gap to prepare for large PLAIN pclusters.

Link: https://lore.kernel.org/r/20250123090109.973463-1-hsiangkao@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Stable-dep-of: b44686c8391b ("erofs: fix large fragment handling")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/erofs/zmap.c | 36 ++++++++++++++++--------------------
 1 file changed, 16 insertions(+), 20 deletions(-)

diff --git a/fs/erofs/zmap.c b/fs/erofs/zmap.c
index b9e35089c9b8d..689437e99a5a3 100644
--- a/fs/erofs/zmap.c
+++ b/fs/erofs/zmap.c
@@ -294,27 +294,23 @@ static int z_erofs_extent_lookback(struct z_erofs_maprecorder *m,
 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;
 
@@ -339,9 +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)
@@ -356,7 +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);
-- 
2.39.5

[PATCH 6.12.y 3/6] erofs: use Z_EROFS_LCLUSTER_TYPE_MAX to simplify switches

[Sasha Levin]

From: Hongzhen Luo <hongzhen@linux.alibaba.com>

[ Upstream commit 3b7781aeaefb627d4e07c1af9be923f9e8047d8b ]

There's no need to enumerate each type.  No logic changes.

Signed-off-by: Hongzhen Luo <hongzhen@linux.alibaba.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Link: https://lore.kernel.org/r/20250210032923.3382136-1-hongzhen@linux.alibaba.com
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Stable-dep-of: b44686c8391b ("erofs: fix large fragment handling")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/erofs/zmap.c | 63 +++++++++++++++++++------------------------------
 1 file changed, 24 insertions(+), 39 deletions(-)

diff --git a/fs/erofs/zmap.c b/fs/erofs/zmap.c
index 689437e99a5a3..d278ebd602816 100644
--- a/fs/erofs/zmap.c
+++ b/fs/erofs/zmap.c
@@ -265,26 +265,22 @@ static int z_erofs_extent_lookback(struct z_erofs_maprecorder *m,
 		if (err)
 			return err;
 
-		switch (m->type) {
-		case Z_EROFS_LCLUSTER_TYPE_NONHEAD:
+		if (m->type >= Z_EROFS_LCLUSTER_TYPE_MAX) {
+			erofs_err(sb, "unknown type %u @ lcn %lu of nid %llu",
+				  m->type, lcn, vi->nid);
+			DBG_BUGON(1);
+			return -EOPNOTSUPP;
+		} else if (m->type == Z_EROFS_LCLUSTER_TYPE_NONHEAD) {
 			lookback_distance = m->delta[0];
 			if (!lookback_distance)
-				goto err_bogus;
+				break;
 			continue;
-		case Z_EROFS_LCLUSTER_TYPE_PLAIN:
-		case Z_EROFS_LCLUSTER_TYPE_HEAD1:
-		case Z_EROFS_LCLUSTER_TYPE_HEAD2:
+		} else {
 			m->headtype = m->type;
 			m->map->m_la = (lcn << lclusterbits) | m->clusterofs;
 			return 0;
-		default:
-			erofs_err(sb, "unknown type %u @ lcn %lu of nid %llu",
-				  m->type, lcn, vi->nid);
-			DBG_BUGON(1);
-			return -EOPNOTSUPP;
 		}
 	}
-err_bogus:
 	erofs_err(sb, "bogus lookback distance %u @ lcn %lu of nid %llu",
 		  lookback_distance, m->lcn, vi->nid);
 	DBG_BUGON(1);
@@ -329,35 +325,28 @@ static int z_erofs_get_extent_compressedlen(struct z_erofs_maprecorder *m,
 	DBG_BUGON(lcn == initial_lcn &&
 		  m->type == Z_EROFS_LCLUSTER_TYPE_NONHEAD);
 
-	switch (m->type) {
-	case Z_EROFS_LCLUSTER_TYPE_PLAIN:
-	case Z_EROFS_LCLUSTER_TYPE_HEAD1:
-	case Z_EROFS_LCLUSTER_TYPE_HEAD2:
+	if (m->type == Z_EROFS_LCLUSTER_TYPE_NONHEAD) {
+		if (m->delta[0] != 1) {
+			erofs_err(sb, "bogus CBLKCNT @ lcn %lu of nid %llu", lcn, vi->nid);
+			DBG_BUGON(1);
+			return -EFSCORRUPTED;
+		}
+		if (m->compressedblks)
+			goto out;
+	} else if (m->type < Z_EROFS_LCLUSTER_TYPE_MAX) {
 		/*
 		 * if the 1st NONHEAD lcluster is actually PLAIN or HEAD type
 		 * rather than CBLKCNT, it's a 1 block-sized pcluster.
 		 */
 		m->compressedblks = 1;
-		break;
-	case Z_EROFS_LCLUSTER_TYPE_NONHEAD:
-		if (m->delta[0] != 1)
-			goto err_bonus_cblkcnt;
-		if (m->compressedblks)
-			break;
-		fallthrough;
-	default:
-		erofs_err(sb, "cannot found CBLKCNT @ lcn %lu of nid %llu", lcn,
-			  vi->nid);
-		DBG_BUGON(1);
-		return -EFSCORRUPTED;
+		goto out;
 	}
+	erofs_err(sb, "cannot found CBLKCNT @ lcn %lu of nid %llu", lcn, vi->nid);
+	DBG_BUGON(1);
+	return -EFSCORRUPTED;
 out:
 	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);
-	DBG_BUGON(1);
-	return -EFSCORRUPTED;
 }
 
 static int z_erofs_get_extent_decompressedlen(struct z_erofs_maprecorder *m)
@@ -386,9 +375,7 @@ static int z_erofs_get_extent_decompressedlen(struct z_erofs_maprecorder *m)
 				m->delta[1] = 1;
 				DBG_BUGON(1);
 			}
-		} else if (m->type == Z_EROFS_LCLUSTER_TYPE_PLAIN ||
-			   m->type == Z_EROFS_LCLUSTER_TYPE_HEAD1 ||
-			   m->type == Z_EROFS_LCLUSTER_TYPE_HEAD2) {
+		} else if (m->type < Z_EROFS_LCLUSTER_TYPE_MAX) {
 			if (lcn != headlcn)
 				break;	/* ends at the next HEAD lcluster */
 			m->delta[1] = 1;
@@ -452,8 +439,7 @@ static int z_erofs_do_map_blocks(struct inode *inode,
 		}
 		/* m.lcn should be >= 1 if endoff < m.clusterofs */
 		if (!m.lcn) {
-			erofs_err(inode->i_sb,
-				  "invalid logical cluster 0 at nid %llu",
+			erofs_err(inode->i_sb, "invalid logical cluster 0 at nid %llu",
 				  vi->nid);
 			err = -EFSCORRUPTED;
 			goto unmap_out;
@@ -469,8 +455,7 @@ static int z_erofs_do_map_blocks(struct inode *inode,
 			goto unmap_out;
 		break;
 	default:
-		erofs_err(inode->i_sb,
-			  "unknown type %u @ offset %llu of nid %llu",
+		erofs_err(inode->i_sb, "unknown type %u @ offset %llu of nid %llu",
 			  m.type, ofs, vi->nid);
 		err = -EOPNOTSUPP;
 		goto unmap_out;
-- 
2.39.5

[PATCH 6.12.y 4/6] erofs: simplify tail inline pcluster handling

[Sasha Levin]

From: Gao Xiang <hsiangkao@linux.alibaba.com>

[ Upstream commit b7710262d743aca112877d12abed61ce8a5d0d98 ]

Use `z_idata_size != 0` to indicate that ztailpacking is enabled.
`Z_EROFS_ADVISE_INLINE_PCLUSTER` cannot be ignored, as `h_idata_size`
could be non-zero prior to erofs-utils 1.6 [1].

Additionally, merge `z_idataoff` and `z_fragmentoff` since these two
features are mutually exclusive for a given inode.

[1] https://git.kernel.org/xiang/erofs-utils/c/547bea3cb71a
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20250225114038.3259726-1-hsiangkao@linux.alibaba.com
Stable-dep-of: b44686c8391b ("erofs: fix large fragment handling")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/erofs/internal.h |  9 ++-------
 fs/erofs/zmap.c     | 20 ++++++++++----------
 2 files changed, 12 insertions(+), 17 deletions(-)

diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h
index 3d06fda70f318..06895e9fec38f 100644
--- a/fs/erofs/internal.h
+++ b/fs/erofs/internal.h
@@ -277,13 +277,8 @@ struct erofs_inode {
 			unsigned char  z_algorithmtype[2];
 			unsigned char  z_logical_clusterbits;
 			unsigned long  z_tailextent_headlcn;
-			union {
-				struct {
-					erofs_off_t    z_idataoff;
-					unsigned short z_idata_size;
-				};
-				erofs_off_t z_fragmentoff;
-			};
+			erofs_off_t    z_fragmentoff;
+			unsigned short z_idata_size;
 		};
 #endif	/* CONFIG_EROFS_FS_ZIP */
 	};
diff --git a/fs/erofs/zmap.c b/fs/erofs/zmap.c
index d278ebd602816..f2ff0cba2bc8c 100644
--- a/fs/erofs/zmap.c
+++ b/fs/erofs/zmap.c
@@ -395,8 +395,8 @@ static int z_erofs_do_map_blocks(struct inode *inode,
 				 struct erofs_map_blocks *map, int flags)
 {
 	struct erofs_inode *const vi = EROFS_I(inode);
-	bool ztailpacking = vi->z_advise & Z_EROFS_ADVISE_INLINE_PCLUSTER;
 	bool fragment = vi->z_advise & Z_EROFS_ADVISE_FRAGMENT_PCLUSTER;
+	bool ztailpacking = vi->z_idata_size;
 	struct z_erofs_maprecorder m = {
 		.inode = inode,
 		.map = map,
@@ -415,9 +415,8 @@ static int z_erofs_do_map_blocks(struct inode *inode,
 	if (err)
 		goto unmap_out;
 
-	if (ztailpacking && (flags & EROFS_GET_BLOCKS_FINDTAIL))
-		vi->z_idataoff = m.nextpackoff;
-
+	if ((flags & EROFS_GET_BLOCKS_FINDTAIL) && ztailpacking)
+		vi->z_fragmentoff = m.nextpackoff;
 	map->m_flags = EROFS_MAP_MAPPED | EROFS_MAP_ENCODED;
 	end = (m.lcn + 1ULL) << lclusterbits;
 
@@ -472,7 +471,7 @@ static int z_erofs_do_map_blocks(struct inode *inode,
 	}
 	if (ztailpacking && m.lcn == vi->z_tailextent_headlcn) {
 		map->m_flags |= EROFS_MAP_META;
-		map->m_pa = vi->z_idataoff;
+		map->m_pa = vi->z_fragmentoff;
 		map->m_plen = vi->z_idata_size;
 	} else if (fragment && m.lcn == vi->z_tailextent_headlcn) {
 		map->m_flags |= EROFS_MAP_FRAGMENT;
@@ -565,6 +564,10 @@ static int z_erofs_fill_inode_lazy(struct inode *inode)
 	vi->z_advise = le16_to_cpu(h->h_advise);
 	vi->z_algorithmtype[0] = h->h_algorithmtype & 15;
 	vi->z_algorithmtype[1] = h->h_algorithmtype >> 4;
+	if (vi->z_advise & Z_EROFS_ADVISE_FRAGMENT_PCLUSTER)
+		vi->z_fragmentoff = le32_to_cpu(h->h_fragmentoff);
+	else if (vi->z_advise & Z_EROFS_ADVISE_INLINE_PCLUSTER)
+		vi->z_idata_size = le16_to_cpu(h->h_idata_size);
 
 	headnr = 0;
 	if (vi->z_algorithmtype[0] >= Z_EROFS_COMPRESSION_MAX ||
@@ -593,18 +596,16 @@ static int z_erofs_fill_inode_lazy(struct inode *inode)
 		goto out_put_metabuf;
 	}
 
-	if (vi->z_advise & Z_EROFS_ADVISE_INLINE_PCLUSTER) {
+	if (vi->z_idata_size) {
 		struct erofs_map_blocks map = {
 			.buf = __EROFS_BUF_INITIALIZER
 		};
 
-		vi->z_idata_size = le16_to_cpu(h->h_idata_size);
 		err = z_erofs_do_map_blocks(inode, &map,
 					    EROFS_GET_BLOCKS_FINDTAIL);
 		erofs_put_metabuf(&map.buf);
 
-		if (!map.m_plen ||
-		    erofs_blkoff(sb, map.m_pa) + map.m_plen > sb->s_blocksize) {
+		if (erofs_blkoff(sb, map.m_pa) + map.m_plen > sb->s_blocksize) {
 			erofs_err(sb, "invalid tail-packing pclustersize %llu",
 				  map.m_plen);
 			err = -EFSCORRUPTED;
@@ -619,7 +620,6 @@ static int z_erofs_fill_inode_lazy(struct inode *inode)
 			.buf = __EROFS_BUF_INITIALIZER
 		};
 
-		vi->z_fragmentoff = le32_to_cpu(h->h_fragmentoff);
 		err = z_erofs_do_map_blocks(inode, &map,
 					    EROFS_GET_BLOCKS_FINDTAIL);
 		erofs_put_metabuf(&map.buf);
-- 
2.39.5

[PATCH 6.12.y 5/6] erofs: clean up header parsing for ztailpacking and fragments

[Sasha Levin]

From: Gao Xiang <hsiangkao@linux.alibaba.com>

[ Upstream commit 540787d38b10dbc16a7d2bc2845752ab1605403a ]

Simplify the logic in z_erofs_fill_inode_lazy() by combining the
handling of ztailpacking and fragments, as they are mutually exclusive.

Note that `h->h_clusterbits >> Z_EROFS_FRAGMENT_INODE_BIT` is handled
above, so no need to duplicate the check.

Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20250224123747.1387122-2-hsiangkao@linux.alibaba.com
Stable-dep-of: b44686c8391b ("erofs: fix large fragment handling")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/erofs/zmap.c | 39 ++++++++++++++-------------------------
 1 file changed, 14 insertions(+), 25 deletions(-)

diff --git a/fs/erofs/zmap.c b/fs/erofs/zmap.c
index f2ff0cba2bc8c..f076cafb304f2 100644
--- a/fs/erofs/zmap.c
+++ b/fs/erofs/zmap.c
@@ -394,7 +394,8 @@ static int z_erofs_get_extent_decompressedlen(struct z_erofs_maprecorder *m)
 static int z_erofs_do_map_blocks(struct inode *inode,
 				 struct erofs_map_blocks *map, int flags)
 {
-	struct erofs_inode *const vi = EROFS_I(inode);
+	struct erofs_inode *vi = EROFS_I(inode);
+	struct super_block *sb = inode->i_sb;
 	bool fragment = vi->z_advise & Z_EROFS_ADVISE_FRAGMENT_PCLUSTER;
 	bool ztailpacking = vi->z_idata_size;
 	struct z_erofs_maprecorder m = {
@@ -438,7 +439,7 @@ static int z_erofs_do_map_blocks(struct inode *inode,
 		}
 		/* m.lcn should be >= 1 if endoff < m.clusterofs */
 		if (!m.lcn) {
-			erofs_err(inode->i_sb, "invalid logical cluster 0 at nid %llu",
+			erofs_err(sb, "invalid logical cluster 0 at nid %llu",
 				  vi->nid);
 			err = -EFSCORRUPTED;
 			goto unmap_out;
@@ -454,7 +455,7 @@ static int z_erofs_do_map_blocks(struct inode *inode,
 			goto unmap_out;
 		break;
 	default:
-		erofs_err(inode->i_sb, "unknown type %u @ offset %llu of nid %llu",
+		erofs_err(sb, "unknown type %u @ offset %llu of nid %llu",
 			  m.type, ofs, vi->nid);
 		err = -EOPNOTSUPP;
 		goto unmap_out;
@@ -473,10 +474,16 @@ static int z_erofs_do_map_blocks(struct inode *inode,
 		map->m_flags |= EROFS_MAP_META;
 		map->m_pa = vi->z_fragmentoff;
 		map->m_plen = vi->z_idata_size;
+		if (erofs_blkoff(sb, map->m_pa) + map->m_plen > sb->s_blocksize) {
+			erofs_err(sb, "invalid tail-packing pclustersize %llu",
+				  map->m_plen);
+			err = -EFSCORRUPTED;
+			goto unmap_out;
+		}
 	} else if (fragment && m.lcn == vi->z_tailextent_headlcn) {
 		map->m_flags |= EROFS_MAP_FRAGMENT;
 	} else {
-		map->m_pa = erofs_pos(inode->i_sb, m.pblk);
+		map->m_pa = erofs_pos(sb, m.pblk);
 		err = z_erofs_get_extent_compressedlen(&m, initial_lcn);
 		if (err)
 			goto unmap_out;
@@ -495,7 +502,7 @@ static int z_erofs_do_map_blocks(struct inode *inode,
 		afmt = m.headtype == Z_EROFS_LCLUSTER_TYPE_HEAD2 ?
 			vi->z_algorithmtype[1] : vi->z_algorithmtype[0];
 		if (!(EROFS_I_SB(inode)->available_compr_algs & (1 << afmt))) {
-			erofs_err(inode->i_sb, "inconsistent algorithmtype %u for nid %llu",
+			erofs_err(sb, "inconsistent algorithmtype %u for nid %llu",
 				  afmt, vi->nid);
 			err = -EFSCORRUPTED;
 			goto unmap_out;
@@ -596,26 +603,8 @@ static int z_erofs_fill_inode_lazy(struct inode *inode)
 		goto out_put_metabuf;
 	}
 
-	if (vi->z_idata_size) {
-		struct erofs_map_blocks map = {
-			.buf = __EROFS_BUF_INITIALIZER
-		};
-
-		err = z_erofs_do_map_blocks(inode, &map,
-					    EROFS_GET_BLOCKS_FINDTAIL);
-		erofs_put_metabuf(&map.buf);
-
-		if (erofs_blkoff(sb, map.m_pa) + map.m_plen > sb->s_blocksize) {
-			erofs_err(sb, "invalid tail-packing pclustersize %llu",
-				  map.m_plen);
-			err = -EFSCORRUPTED;
-		}
-		if (err < 0)
-			goto out_put_metabuf;
-	}
-
-	if (vi->z_advise & Z_EROFS_ADVISE_FRAGMENT_PCLUSTER &&
-	    !(h->h_clusterbits >> Z_EROFS_FRAGMENT_INODE_BIT)) {
+	if (vi->z_idata_size ||
+	    (vi->z_advise & Z_EROFS_ADVISE_FRAGMENT_PCLUSTER)) {
 		struct erofs_map_blocks map = {
 			.buf = __EROFS_BUF_INITIALIZER
 		};
-- 
2.39.5

[PATCH 6.12.y 6/6] erofs: fix large fragment handling

[Sasha Levin]

From: Gao Xiang <hsiangkao@linux.alibaba.com>

[ Upstream commit b44686c8391b427fb1c85a31c35077e6947c6d90 ]

Fragments aren't limited by Z_EROFS_PCLUSTER_MAX_DSIZE. However, if
a fragment's logical length is larger than Z_EROFS_PCLUSTER_MAX_DSIZE
but the fragment is not the whole inode, it currently returns
-EOPNOTSUPP because m_flags has the wrong EROFS_MAP_ENCODED flag set.
It is not intended by design but should be rare, as it can only be
reproduced by mkfs with `-Eall-fragments` in a specific case.

Let's normalize fragment m_flags using the new EROFS_MAP_FRAGMENT.

Reported-by: Axel Fontaine <axel@axelfontaine.com>
Closes: https://github.com/erofs/erofs-utils/issues/23
Fixes: 7c3ca1838a78 ("erofs: restrict pcluster size limitations")
Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Link: https://lore.kernel.org/r/20250711195826.3601157-1-hsiangkao@linux.alibaba.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/erofs/internal.h | 4 +++-
 fs/erofs/zdata.c    | 2 +-
 fs/erofs/zmap.c     | 7 +++----
 3 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h
index 06895e9fec38f..856463a702b2c 100644
--- a/fs/erofs/internal.h
+++ b/fs/erofs/internal.h
@@ -324,10 +324,12 @@ static inline struct folio *erofs_grab_folio_nowait(struct address_space *as,
 /* The length of extent is full */
 #define EROFS_MAP_FULL_MAPPED	0x0008
 /* Located in the special packed inode */
-#define EROFS_MAP_FRAGMENT	0x0010
+#define __EROFS_MAP_FRAGMENT	0x0010
 /* The extent refers to partial decompressed data */
 #define EROFS_MAP_PARTIAL_REF	0x0020
 
+#define EROFS_MAP_FRAGMENT	(EROFS_MAP_MAPPED | __EROFS_MAP_FRAGMENT)
+
 struct erofs_map_blocks {
 	struct erofs_buf buf;
 
diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c
index 94c1e2d64df96..f35d2eb0ed11c 100644
--- a/fs/erofs/zdata.c
+++ b/fs/erofs/zdata.c
@@ -1016,7 +1016,7 @@ static int z_erofs_scan_folio(struct z_erofs_frontend *f,
 		if (!(map->m_flags & EROFS_MAP_MAPPED)) {
 			folio_zero_segment(folio, cur, end);
 			tight = false;
-		} else if (map->m_flags & EROFS_MAP_FRAGMENT) {
+		} else if (map->m_flags & __EROFS_MAP_FRAGMENT) {
 			erofs_off_t fpos = offset + cur - map->m_la;
 
 			err = z_erofs_read_fragment(inode->i_sb, folio, cur,
diff --git a/fs/erofs/zmap.c b/fs/erofs/zmap.c
index f076cafb304f2..25a4b82c183c0 100644
--- a/fs/erofs/zmap.c
+++ b/fs/erofs/zmap.c
@@ -481,7 +481,7 @@ static int z_erofs_do_map_blocks(struct inode *inode,
 			goto unmap_out;
 		}
 	} else if (fragment && m.lcn == vi->z_tailextent_headlcn) {
-		map->m_flags |= EROFS_MAP_FRAGMENT;
+		map->m_flags = EROFS_MAP_FRAGMENT;
 	} else {
 		map->m_pa = erofs_pos(sb, m.pblk);
 		err = z_erofs_get_extent_compressedlen(&m, initial_lcn);
@@ -644,8 +644,7 @@ int z_erofs_map_blocks_iter(struct inode *inode, struct erofs_map_blocks *map,
 			    !vi->z_tailextent_headlcn) {
 				map->m_la = 0;
 				map->m_llen = inode->i_size;
-				map->m_flags = EROFS_MAP_MAPPED |
-					EROFS_MAP_FULL_MAPPED | EROFS_MAP_FRAGMENT;
+				map->m_flags = EROFS_MAP_FRAGMENT;
 			} else {
 				err = z_erofs_do_map_blocks(inode, map, flags);
 			}
@@ -678,7 +677,7 @@ static int z_erofs_iomap_begin_report(struct inode *inode, loff_t offset,
 	iomap->length = map.m_llen;
 	if (map.m_flags & EROFS_MAP_MAPPED) {
 		iomap->type = IOMAP_MAPPED;
-		iomap->addr = map.m_flags & EROFS_MAP_FRAGMENT ?
+		iomap->addr = map.m_flags & __EROFS_MAP_FRAGMENT ?
 			      IOMAP_NULL_ADDR : map.m_pa;
 	} else {
 		iomap->type = IOMAP_HOLE;
-- 
2.39.5