[PATCH v2 00/18] fs/ceph: optimize struct layouts

[PATCH v2 00/18] fs/ceph: optimize struct layouts

[Max Kellermann]

This patch set aims to reduce the memory usage of the Ceph filesystems
by optimizing the layout of structs, most importantly struct
ceph_inode_info:

- use `bool` instead of `int` for booelans
- use `u32` instead of `u64` where possible
- reorder fields to eliminate padding holes
- eliminate redundant fields

Without this patch set, ceph_inode_info looks like this with pahole:

	/* size: 1456, cachelines: 23, members: 79 */
	/* sum members: 1424, holes: 8, sum holes: 32 */
	/* member types with holes: 3, total: 3 */

With this patch set, struct ceph_inode_info got smaller by 96 bytes:

	/* size: 1360, cachelines: 22, members: 76 */
	/* member types with holes: 1, total: 1 */

struct ceph_cap shrinks by 24 bytes:

	/* size: 120, cachelines: 2, members: 12 */

	/* size: 96, cachelines: 2, members: 10 */

struct ceph_snap_realm shrinks by 24 bytes, too:

	/* size: 232, cachelines: 4, members: 21 */
	/* sum members: 216, holes: 3, sum holes: 12 */

	/* size: 208, cachelines: 4, members: 20 */

---
v1->v2:
 - fix CONFIG_FS_ENCRYPTION check in "i_truncate_pagecache_size" patch
 - add patches to shrink ceph_cap and ceph_snap_realm

Max Kellermann (18):
  fs/ceph/super: remove unused field `i_cap_migration_resv`
  fs/ceph/super: make field `i_truncate_pagecache_size` optional
  include/ceph/ceph_fs.h: convert `pool_id` to u32
  fs/ceph/super.h: convert ceph_inode_xattr fields to `bool`
  fs/ceph/super.h: convert ceph_cap_snap.writing fields to `bool`
  fs/ceph: consistently use `u32` for `time_warp_seq`
  fs/ceph/super: reorder fields to eliminate padding holes
  fs/ceph: remove i_truncate_mutex, use i_fragtree_mutex for both
  fs/ceph/super.h: add `const` to helpers
  fs/ceph/super.h: add helper ceph_in_snap()
  fs/ceph: use ceph_vino() etc. instead of accessing i_vino directly
  fs/ceph: remove redundant inode number from ceph_inode_info
  fs/ceph: remove unused field `ceph_cap.last_used`
  fs/ceph: convert ceph_cap.queue_release to bool
  fs/ceph/super: move `ceph_cap.caps_item` into the union
  fs/ceph/snap: add a kmem_cache for struct ceph_snap_realm
  fs/ceph/super: reorder struct ceph_snap_realm fields
  fs/ceph/super: remove redundant field `ceph_snap_realm.parent_ino`

 fs/ceph/acl.c                |   2 +-
 fs/ceph/addr.c               |  23 ++++---
 fs/ceph/cache.c              |   4 +-
 fs/ceph/caps.c               |  14 ++--
 fs/ceph/dir.c                |  20 +++---
 fs/ceph/export.c             |   8 +--
 fs/ceph/file.c               |  28 ++++----
 fs/ceph/inode.c              |  38 +++++++----
 fs/ceph/mds_client.c         |  16 ++---
 fs/ceph/mds_client.h         |   2 +-
 fs/ceph/quota.c              |   6 +-
 fs/ceph/snap.c               |  17 +++--
 fs/ceph/super.c              |   9 +++
 fs/ceph/super.h              | 123 +++++++++++++++++++++++++----------
 fs/ceph/util.c               |   8 +--
 fs/ceph/xattr.c              |  18 ++---
 include/linux/ceph/ceph_fs.h |   2 +-
 include/linux/ceph/libceph.h |   1 +
 18 files changed, 204 insertions(+), 135 deletions(-)

-- 
2.47.3

[PATCH v2 01/18] fs/ceph/super: remove unused field `i_cap_migration_resv`

[Max Kellermann]

This field was added 17 years ago by commit de57606c23afd ("ceph:
client types") but it was never used.

This reduces the size of `struct ceph_inode_info` by 8 bytes.

Fixes: de57606c23afd ("ceph: client types")
Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
---
 fs/ceph/super.h | 1 -
 1 file changed, 1 deletion(-)

diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 1d6aab060780..3cbd320b49a8 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -450,7 +450,6 @@ struct ceph_inode_info {
 	wait_queue_head_t i_cap_wq;      /* threads waiting on a capability */
 	unsigned long i_hold_caps_max; /* jiffies */
 	struct list_head i_cap_delay_list;  /* for delayed cap release to mds */
-	struct ceph_cap_reservation i_cap_migration_resv;
 	struct list_head i_cap_snaps;   /* snapped state pending flush to mds */
 	struct ceph_snap_context *i_head_snapc;  /* set if wr_buffer_head > 0 or
 						    dirty|flushing caps */
-- 
2.47.3

[PATCH v2 02/18] fs/ceph/super: make field `i_truncate_pagecache_size` optional

[Max Kellermann]

This field is only used with CONFIG_FS_ENCRYPTION; without it, it
always equals `i_truncate_size`.

This reduces the size of `struct ceph_inode_info` by 8 bytes on
kernels that have filesystem encryption disabled.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
---
 fs/ceph/inode.c |  8 ++++++--
 fs/ceph/super.h | 11 +++++++++++
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index 61d7c0b8161f..bdb82f123033 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -681,7 +681,9 @@ struct inode *ceph_alloc_inode(struct super_block *sb)
 	ci->i_truncate_seq = 0;
 	ci->i_truncate_size = 0;
 	ci->i_truncate_pending = 0;
+#ifdef CONFIG_FS_ENCRYPTION
 	ci->i_truncate_pagecache_size = 0;
+#endif
 
 	ci->i_max_size = 0;
 	ci->i_reported_size = 0;
@@ -866,6 +868,7 @@ int ceph_fill_file_size(struct inode *inode, int issued,
 
 		ci->i_truncate_size = truncate_size;
 
+#ifdef CONFIG_FS_ENCRYPTION
 		if (IS_ENCRYPTED(inode)) {
 			doutc(cl, "truncate_pagecache_size %lld -> %llu\n",
 			      ci->i_truncate_pagecache_size, size);
@@ -873,6 +876,7 @@ int ceph_fill_file_size(struct inode *inode, int issued,
 		} else {
 			ci->i_truncate_pagecache_size = truncate_size;
 		}
+#endif
 	}
 	return queue_trunc;
 }
@@ -2332,7 +2336,7 @@ void __ceph_do_pending_vmtruncate(struct inode *inode)
 	/* there should be no reader or writer */
 	WARN_ON_ONCE(ci->i_rd_ref || ci->i_wr_ref);
 
-	to = ci->i_truncate_pagecache_size;
+	to = ceph_get_truncate_pagecache_size(ci);
 	wrbuffer_refs = ci->i_wrbuffer_ref;
 	doutc(cl, "%p %llx.%llx (%d) to %lld\n", inode, ceph_vinop(inode),
 	      ci->i_truncate_pending, to);
@@ -2342,7 +2346,7 @@ void __ceph_do_pending_vmtruncate(struct inode *inode)
 	truncate_pagecache(inode, to);
 
 	spin_lock(&ci->i_ceph_lock);
-	if (to == ci->i_truncate_pagecache_size) {
+	if (to == ceph_get_truncate_pagecache_size(ci)) {
 		ci->i_truncate_pending = 0;
 		finish = 1;
 	}
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 3cbd320b49a8..7023af704e14 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -468,11 +468,14 @@ struct ceph_inode_info {
 	u32 i_truncate_seq;        /* last truncate to smaller size */
 	u64 i_truncate_size;       /*  and the size we last truncated down to */
 	int i_truncate_pending;    /*  still need to call vmtruncate */
+
+#ifdef CONFIG_FS_ENCRYPTION
 	/*
 	 * For none fscrypt case it equals to i_truncate_size or it will
 	 * equals to fscrypt_file_size
 	 */
 	u64 i_truncate_pagecache_size;
+#endif
 
 	u64 i_max_size;            /* max file size authorized by mds */
 	u64 i_reported_size; /* (max_)size reported to or requested of mds */
@@ -667,6 +670,14 @@ static inline struct inode *ceph_find_inode(struct super_block *sb,
 	return ilookup5(sb, (unsigned long)vino.ino, ceph_ino_compare, &vino);
 }
 
+static inline u64 ceph_get_truncate_pagecache_size(const struct ceph_inode_info *ci)
+{
+#ifdef CONFIG_FS_ENCRYPTION
+	return ci->i_truncate_pagecache_size;
+#else
+	return ci->i_truncate_size;
+#endif
+}
 
 /*
  * Ceph inode.
-- 
2.47.3

[PATCH v2 03/18] include/ceph/ceph_fs.h: convert `pool_id` to u32

[Max Kellermann]

While the Ceph OSD protocol transmits OSD pool ids as 64 bit integers,
the MDS protocol is limited to 32 bits.  This is a protocol limitation
we cannot fix, but it gives us the chance to reduce the struct sizes
by only using the integer size we really need.

There is one caveat: previously, -1 was used to indicate "invalid pool
id".  This patch changes this magic value to 0 (i.e. removes the
special-case code from ceph_file_layout_{from,to}_legacy()).  This is
fine because on the wire, this magic value is 0, too.

This reduces the size of `struct ceph_inode_info` by 16 bytes (because
it contains `struct ceph_file_layout` twice, and that struct shrinks
by 8 bytes; the small pool_id now fits in the existing padding hole).

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
---
 fs/ceph/addr.c               | 16 ++++++++--------
 fs/ceph/caps.c               |  2 +-
 fs/ceph/inode.c              |  2 +-
 fs/ceph/mds_client.h         |  2 +-
 fs/ceph/util.c               |  8 +-------
 fs/ceph/xattr.c              | 10 +++++-----
 include/linux/ceph/ceph_fs.h |  2 +-
 7 files changed, 18 insertions(+), 24 deletions(-)

diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index 61bd6d92ff25..481654872e9f 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -2381,7 +2381,7 @@ enum {
 };
 
 static int __ceph_pool_perm_get(struct ceph_inode_info *ci,
-				s64 pool, struct ceph_string *pool_ns)
+				u32 pool, struct ceph_string *pool_ns)
 {
 	struct ceph_fs_client *fsc = ceph_inode_to_fs_client(&ci->netfs.inode);
 	struct ceph_mds_client *mdsc = fsc->mdsc;
@@ -2420,10 +2420,10 @@ static int __ceph_pool_perm_get(struct ceph_inode_info *ci,
 		goto out;
 
 	if (pool_ns)
-		doutc(cl, "pool %lld ns %.*s no perm cached\n", pool,
+		doutc(cl, "pool %u ns %.*s no perm cached\n", pool,
 		      (int)pool_ns->len, pool_ns->str);
 	else
-		doutc(cl, "pool %lld no perm cached\n", pool);
+		doutc(cl, "pool %u no perm cached\n", pool);
 
 	down_write(&mdsc->pool_perm_rwsem);
 	p = &mdsc->pool_perm_tree.rb_node;
@@ -2548,10 +2548,10 @@ static int __ceph_pool_perm_get(struct ceph_inode_info *ci,
 	if (!err)
 		err = have;
 	if (pool_ns)
-		doutc(cl, "pool %lld ns %.*s result = %d\n", pool,
+		doutc(cl, "pool %u ns %.*s result = %d\n", pool,
 		      (int)pool_ns->len, pool_ns->str, err);
 	else
-		doutc(cl, "pool %lld result = %d\n", pool, err);
+		doutc(cl, "pool %u result = %d\n", pool, err);
 	return err;
 }
 
@@ -2560,7 +2560,7 @@ int ceph_pool_perm_check(struct inode *inode, int need)
 	struct ceph_client *cl = ceph_inode_to_client(inode);
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	struct ceph_string *pool_ns;
-	s64 pool;
+	u32 pool;
 	int ret;
 	unsigned long flags;
 
@@ -2588,11 +2588,11 @@ int ceph_pool_perm_check(struct inode *inode, int need)
 check:
 	if (flags & CEPH_I_POOL_PERM) {
 		if ((need & CEPH_CAP_FILE_RD) && !(flags & CEPH_I_POOL_RD)) {
-			doutc(cl, "pool %lld no read perm\n", pool);
+			doutc(cl, "pool %u no read perm\n", pool);
 			return -EPERM;
 		}
 		if ((need & CEPH_CAP_FILE_WR) && !(flags & CEPH_I_POOL_WR)) {
-			doutc(cl, "pool %lld no write perm\n", pool);
+			doutc(cl, "pool %u no write perm\n", pool);
 			return -EPERM;
 		}
 		return 0;
diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 4b37d9ffdf7f..39dad1a528b5 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -3641,7 +3641,7 @@ static void handle_cap_grant(struct inode *inode,
 
 	if (newcaps & (CEPH_CAP_ANY_FILE_RD | CEPH_CAP_ANY_FILE_WR)) {
 		/* file layout may have changed */
-		s64 old_pool = ci->i_layout.pool_id;
+		u32 old_pool = ci->i_layout.pool_id;
 		struct ceph_string *old_ns;
 
 		ceph_file_layout_from_legacy(&ci->i_layout, &grant->layout);
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index bdb82f123033..cd1e09c32eba 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -1176,7 +1176,7 @@ int ceph_fill_inode(struct inode *inode, struct page *locked_page,
 	if (new_version ||
 	    (new_issued & (CEPH_CAP_ANY_FILE_RD | CEPH_CAP_ANY_FILE_WR))) {
 		u64 size = le64_to_cpu(info->size);
-		s64 old_pool = ci->i_layout.pool_id;
+		u32 old_pool = ci->i_layout.pool_id;
 		struct ceph_string *old_ns;
 
 		ceph_file_layout_from_legacy(&ci->i_layout, &info->layout);
diff --git a/fs/ceph/mds_client.h b/fs/ceph/mds_client.h
index 731d6ad04956..d59bc904f0ce 100644
--- a/fs/ceph/mds_client.h
+++ b/fs/ceph/mds_client.h
@@ -440,7 +440,7 @@ struct ceph_mds_request {
 struct ceph_pool_perm {
 	struct rb_node node;
 	int perm;
-	s64 pool;
+	u32 pool;
 	size_t pool_ns_len;
 	char pool_ns[];
 };
diff --git a/fs/ceph/util.c b/fs/ceph/util.c
index 2c34875675bf..5bb40af08b1c 100644
--- a/fs/ceph/util.c
+++ b/fs/ceph/util.c
@@ -35,9 +35,6 @@ void ceph_file_layout_from_legacy(struct ceph_file_layout *fl,
 	fl->stripe_count = le32_to_cpu(legacy->fl_stripe_count);
 	fl->object_size = le32_to_cpu(legacy->fl_object_size);
 	fl->pool_id = le32_to_cpu(legacy->fl_pg_pool);
-	if (fl->pool_id == 0 && fl->stripe_unit == 0 &&
-	    fl->stripe_count == 0 && fl->object_size == 0)
-		fl->pool_id = -1;
 }
 
 void ceph_file_layout_to_legacy(struct ceph_file_layout *fl,
@@ -46,10 +43,7 @@ void ceph_file_layout_to_legacy(struct ceph_file_layout *fl,
 	legacy->fl_stripe_unit = cpu_to_le32(fl->stripe_unit);
 	legacy->fl_stripe_count = cpu_to_le32(fl->stripe_count);
 	legacy->fl_object_size = cpu_to_le32(fl->object_size);
-	if (fl->pool_id >= 0)
-		legacy->fl_pg_pool = cpu_to_le32(fl->pool_id);
-	else
-		legacy->fl_pg_pool = 0;
+	legacy->fl_pg_pool = cpu_to_le32(fl->pool_id);
 }
 
 int ceph_flags_to_mode(int flags)
diff --git a/fs/ceph/xattr.c b/fs/ceph/xattr.c
index 860fc8e1867d..124dde705e79 100644
--- a/fs/ceph/xattr.c
+++ b/fs/ceph/xattr.c
@@ -50,7 +50,7 @@ static bool ceph_vxattrcb_layout_exists(struct ceph_inode_info *ci)
 {
 	struct ceph_file_layout *fl = &ci->i_layout;
 	return (fl->stripe_unit > 0 || fl->stripe_count > 0 ||
-		fl->object_size > 0 || fl->pool_id >= 0 ||
+		fl->object_size > 0 || fl->pool_id > 0 ||
 		rcu_dereference_raw(fl->pool_ns) != NULL);
 }
 
@@ -61,7 +61,7 @@ static ssize_t ceph_vxattrcb_layout(struct ceph_inode_info *ci, char *val,
 	struct ceph_client *cl = fsc->client;
 	struct ceph_osd_client *osdc = &fsc->client->osdc;
 	struct ceph_string *pool_ns;
-	s64 pool = ci->i_layout.pool_id;
+	u32 pool = ci->i_layout.pool_id;
 	const char *pool_name;
 	const char *ns_field = " pool_namespace=";
 	char buf[128];
@@ -81,7 +81,7 @@ static ssize_t ceph_vxattrcb_layout(struct ceph_inode_info *ci, char *val,
 		total_len = len + strlen(pool_name);
 	} else {
 		len = snprintf(buf, sizeof(buf),
-		"stripe_unit=%u stripe_count=%u object_size=%u pool=%lld",
+		"stripe_unit=%u stripe_count=%u object_size=%u pool=%u",
 		ci->i_layout.stripe_unit, ci->i_layout.stripe_count,
 		ci->i_layout.object_size, pool);
 		total_len = len;
@@ -164,7 +164,7 @@ static ssize_t ceph_vxattrcb_layout_pool(struct ceph_inode_info *ci,
 	ssize_t ret;
 	struct ceph_fs_client *fsc = ceph_sb_to_fs_client(ci->netfs.inode.i_sb);
 	struct ceph_osd_client *osdc = &fsc->client->osdc;
-	s64 pool = ci->i_layout.pool_id;
+	u32 pool = ci->i_layout.pool_id;
 	const char *pool_name;
 
 	down_read(&osdc->lock);
@@ -174,7 +174,7 @@ static ssize_t ceph_vxattrcb_layout_pool(struct ceph_inode_info *ci,
 		if (ret <= size)
 			memcpy(val, pool_name, ret);
 	} else {
-		ret = ceph_fmt_xattr(val, size, "%lld", pool);
+		ret = ceph_fmt_xattr(val, size, "%u", pool);
 	}
 	up_read(&osdc->lock);
 	return ret;
diff --git a/include/linux/ceph/ceph_fs.h b/include/linux/ceph/ceph_fs.h
index 69ac3e55a3fe..7faa18493a07 100644
--- a/include/linux/ceph/ceph_fs.h
+++ b/include/linux/ceph/ceph_fs.h
@@ -69,7 +69,7 @@ struct ceph_file_layout {
 	u32 stripe_unit;   /* stripe unit, in bytes */
 	u32 stripe_count;  /* over this many objects */
 	u32 object_size;   /* until objects are this big */
-	s64 pool_id;        /* rados pool id */
+	u32 pool_id;        /* rados pool id */
 	struct ceph_string __rcu *pool_ns; /* rados pool namespace */
 };
 
-- 
2.47.3

[PATCH v2 04/18] fs/ceph/super.h: convert ceph_inode_xattr fields to `bool`

[Max Kellermann]

This reduces the size of `struct ceph_inode_xattr` by 8 bytes.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
---
 fs/ceph/super.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 7023af704e14..a3dae2c0bbee 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -320,10 +320,10 @@ struct ceph_inode_xattr {
 	int name_len;
 	const char *val;
 	int val_len;
-	int dirty;
+	bool dirty;
 
-	int should_free_name;
-	int should_free_val;
+	bool should_free_name;
+	bool should_free_val;
 };
 
 /*
-- 
2.47.3

[PATCH v2 05/18] fs/ceph/super.h: convert ceph_cap_snap.writing fields to `bool`

[Max Kellermann]

This will allow better struct packing.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
---
 fs/ceph/caps.c  | 2 +-
 fs/ceph/snap.c  | 4 ++--
 fs/ceph/super.h | 2 +-
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 39dad1a528b5..372b239f6a36 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -3291,7 +3291,7 @@ static void __ceph_put_cap_refs(struct ceph_inode_info *ci, int had,
 					struct ceph_cap_snap,
 					ci_item);
 
-		capsnap->writing = 0;
+		capsnap->writing = false;
 		if (ceph_try_drop_cap_snap(ci, capsnap))
 			/* put the ref held by ceph_queue_cap_snap() */
 			put++;
diff --git a/fs/ceph/snap.c b/fs/ceph/snap.c
index 9b79a5eaca93..94964e0952bd 100644
--- a/fs/ceph/snap.c
+++ b/fs/ceph/snap.c
@@ -521,7 +521,7 @@ static bool has_new_snaps(struct ceph_snap_context *o,
  * However, if a (sync) write is currently in-progress when we apply
  * the snapshot, we have to wait until the write succeeds or fails
  * (and a final size/mtime is known).  In this case the
- * cap_snap->writing = 1, and is said to be "pending."  When the write
+ * cap_snap->writing = true, and is said to be "pending."  When the write
  * finishes, we __ceph_finish_cap_snap().
  *
  * Caller must hold snap_rwsem for read (i.e., the realm topology won't
@@ -627,7 +627,7 @@ static void ceph_queue_cap_snap(struct ceph_inode_info *ci,
 		doutc(cl, "%p %llx.%llx cap_snap %p snapc %p seq %llu used WR,"
 		      " now pending\n", inode, ceph_vinop(inode), capsnap,
 		      old_snapc, old_snapc->seq);
-		capsnap->writing = 1;
+		capsnap->writing = true;
 	} else {
 		/* note mtime, size NOW. */
 		__ceph_finish_cap_snap(ci, capsnap);
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index a3dae2c0bbee..0d3363b0a33b 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -271,7 +271,7 @@ struct ceph_cap_snap {
 	u64 time_warp_seq;
 	u64 truncate_size;
 	u32 truncate_seq;
-	int writing;   /* a sync write is still in progress */
+	bool writing;   /* a sync write is still in progress */
 	int dirty_pages;     /* dirty pages awaiting writeback */
 	bool inline_data;
 	bool need_flush;
-- 
2.47.3

[PATCH v2 06/18] fs/ceph: consistently use `u32` for `time_warp_seq`

[Max Kellermann]

Previously, both `u32` and `u64` was used with implicit casts.  All
this does is add useless overhead.

This will allow better struct packing in `struct ceph_cap_snap`.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
---
 fs/ceph/inode.c | 6 +++---
 fs/ceph/super.h | 4 ++--
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index cd1e09c32eba..e79ba09f2cdf 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -916,7 +916,7 @@ void ceph_inode_set_subvolume(struct inode *inode, u64 subvolume_id)
 }
 
 void ceph_fill_file_time(struct inode *inode, int issued,
-			 u64 time_warp_seq, struct timespec64 *ctime,
+			 u32 time_warp_seq, struct timespec64 *ctime,
 			 struct timespec64 *mtime, struct timespec64 *atime)
 {
 	struct ceph_client *cl = ceph_inode_to_client(inode);
@@ -940,7 +940,7 @@ void ceph_fill_file_time(struct inode *inode, int issued,
 		    ceph_seq_cmp(time_warp_seq, ci->i_time_warp_seq) > 0) {
 			/* the MDS did a utimes() */
 			doutc(cl, "mtime %ptSp -> %ptSp tw %d -> %d\n", &imtime, mtime,
-			      ci->i_time_warp_seq, (int)time_warp_seq);
+			      ci->i_time_warp_seq, time_warp_seq);
 
 			inode_set_mtime_to_ts(inode, *mtime);
 			inode_set_atime_to_ts(inode, *atime);
@@ -972,7 +972,7 @@ void ceph_fill_file_time(struct inode *inode, int issued,
 		}
 	}
 	if (warn) /* time_warp_seq shouldn't go backwards */
-		doutc(cl, "%p mds time_warp_seq %llu < %u\n", inode,
+		doutc(cl, "%p mds time_warp_seq %u < %u\n", inode,
 		      time_warp_seq, ci->i_time_warp_seq);
 }
 
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 0d3363b0a33b..67411a5d8b91 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -268,7 +268,7 @@ struct ceph_cap_snap {
 	u64 size;
 	u64 change_attr;
 	struct timespec64 mtime, atime, ctime, btime;
-	u64 time_warp_seq;
+	u32 time_warp_seq;
 	u64 truncate_size;
 	u32 truncate_seq;
 	bool writing;   /* a sync write is still in progress */
@@ -1099,7 +1099,7 @@ extern int ceph_fill_file_size(struct inode *inode, int issued,
 			       u32 truncate_seq, u64 truncate_size, u64 size);
 extern void ceph_inode_set_subvolume(struct inode *inode, u64 subvolume_id);
 extern void ceph_fill_file_time(struct inode *inode, int issued,
-				u64 time_warp_seq, struct timespec64 *ctime,
+				u32 time_warp_seq, struct timespec64 *ctime,
 				struct timespec64 *mtime,
 				struct timespec64 *atime);
 extern int ceph_fill_inode(struct inode *inode, struct page *locked_page,
-- 
2.47.3

[PATCH v2 07/18] fs/ceph/super: reorder fields to eliminate padding holes

[Max Kellermann]

This reduces the size of `struct ceph_inode_info` by 32 bytes.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
---
 fs/ceph/super.h | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 67411a5d8b91..05452bc7eac1 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -250,6 +250,9 @@ struct ceph_cap_flush {
  */
 struct ceph_cap_snap {
 	refcount_t nref;
+
+	umode_t mode;
+
 	struct list_head ci_item;
 
 	struct ceph_cap_flush cap_flush;
@@ -258,7 +261,6 @@ struct ceph_cap_snap {
 	int issued, dirty;
 	struct ceph_snap_context *context;
 
-	umode_t mode;
 	kuid_t uid;
 	kgid_t gid;
 
@@ -268,11 +270,12 @@ struct ceph_cap_snap {
 	u64 size;
 	u64 change_attr;
 	struct timespec64 mtime, atime, ctime, btime;
-	u32 time_warp_seq;
 	u64 truncate_size;
 	u32 truncate_seq;
-	bool writing;   /* a sync write is still in progress */
+	u32 time_warp_seq;
 	int dirty_pages;     /* dirty pages awaiting writeback */
+
+	bool writing;   /* a sync write is still in progress */
 	bool inline_data;
 	bool need_flush;
 };
@@ -317,8 +320,8 @@ struct ceph_inode_xattr {
 	struct rb_node node;
 
 	const char *name;
-	int name_len;
 	const char *val;
+	int name_len;
 	int val_len;
 	bool dirty;
 
@@ -379,9 +382,9 @@ struct ceph_inode_info {
 
 	spinlock_t i_ceph_lock;
 
+	u32 i_time_warp_seq;
 	u64 i_version;
 	u64 i_inline_version;
-	u32 i_time_warp_seq;
 
 	unsigned long i_ceph_flags;
 	atomic64_t i_release_count;
@@ -412,8 +415,8 @@ struct ceph_inode_info {
 
 	s32 i_dir_pin;
 
-	struct rb_root i_fragtree;
 	int i_fragtree_nsplits;
+	struct rb_root i_fragtree;
 	struct mutex i_fragtree_mutex;
 
 	struct ceph_inode_xattrs_info i_xattrs;
@@ -453,7 +456,6 @@ struct ceph_inode_info {
 	struct list_head i_cap_snaps;   /* snapped state pending flush to mds */
 	struct ceph_snap_context *i_head_snapc;  /* set if wr_buffer_head > 0 or
 						    dirty|flushing caps */
-	unsigned i_snap_caps;           /* cap bits for snapped files */
 	/*
 	 * Written under i_ceph_lock, read via READ_ONCE()
 	 * from diagnostic paths.
@@ -465,8 +467,8 @@ struct ceph_inode_info {
 	int i_nr_by_mode[CEPH_FILE_MODE_BITS];  /* open file counts */
 
 	struct mutex i_truncate_mutex;
-	u32 i_truncate_seq;        /* last truncate to smaller size */
 	u64 i_truncate_size;       /*  and the size we last truncated down to */
+	u32 i_truncate_seq;        /* last truncate to smaller size */
 	int i_truncate_pending;    /*  still need to call vmtruncate */
 
 #ifdef CONFIG_FS_ENCRYPTION
@@ -495,6 +497,8 @@ struct ceph_inode_info {
 	struct list_head i_unsafe_iops;   /* uncommitted mds inode ops */
 	spinlock_t i_unsafe_lock;
 
+	unsigned int i_snap_caps;           /* cap bits for snapped files */
+
 	union {
 		struct ceph_snap_realm *i_snap_realm; /* snap realm (if caps) */
 		struct ceph_snapid_map *i_snapid_map; /* snapid -> dev_t */
-- 
2.47.3

[PATCH v2 08/18] fs/ceph: remove i_truncate_mutex, use i_fragtree_mutex for both

[Max Kellermann]

`i_fragtree_mutex` is only used for directories and `i_truncate_mutex`
is only used for regular files.  Since these two fields will never be
both be used on any given object, let's merge them into one.

(This is a minimal diff that defines a preprocessor macro, to avoid
refactoring all code lines using these two mutexes.)

This reduces the size of `struct ceph_inode_info` by 8 bytes.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
---
 fs/ceph/inode.c | 1 -
 fs/ceph/super.h | 6 +++++-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index e79ba09f2cdf..1f65aa387008 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -677,7 +677,6 @@ struct inode *ceph_alloc_inode(struct super_block *sb)
 	for (i = 0; i < CEPH_FILE_MODE_BITS; i++)
 		ci->i_nr_by_mode[i] = 0;
 
-	mutex_init(&ci->i_truncate_mutex);
 	ci->i_truncate_seq = 0;
 	ci->i_truncate_size = 0;
 	ci->i_truncate_pending = 0;
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 05452bc7eac1..35399689f0c1 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -466,7 +466,11 @@ struct ceph_inode_info {
 	unsigned long i_last_wr;
 	int i_nr_by_mode[CEPH_FILE_MODE_BITS];  /* open file counts */
 
-	struct mutex i_truncate_mutex;
+/* since i_fragtree_mutex is only used for directories and
+   i_truncate_mutex is only used for regular files, we use the same
+   field for both */
+#define i_truncate_mutex i_fragtree_mutex
+
 	u64 i_truncate_size;       /*  and the size we last truncated down to */
 	u32 i_truncate_seq;        /* last truncate to smaller size */
 	int i_truncate_pending;    /*  still need to call vmtruncate */
-- 
2.47.3

[PATCH v2 09/18] fs/ceph/super.h: add `const` to helpers

[Max Kellermann]

This documents that these functions do not modify the parameters.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
---
 fs/ceph/super.h | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 35399689f0c1..ab6fa8319c79 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -588,7 +588,7 @@ static inline u32 ceph_ino_to_ino32(u64 vino)
  * we do want to set it to something, so that generic vfs code has an
  * appropriate value for tracepoints and the like.
  */
-static inline ino_t ceph_vino_to_ino_t(struct ceph_vino vino)
+static inline ino_t ceph_vino_to_ino_t(const struct ceph_vino vino)
 {
 	if (sizeof(ino_t) == sizeof(u32))
 		return ceph_ino_to_ino32(vino.ino);
@@ -598,12 +598,12 @@ static inline ino_t ceph_vino_to_ino_t(struct ceph_vino vino)
 /* for printf-style formatting */
 #define ceph_vinop(i) ceph_inode(i)->i_vino.ino, ceph_inode(i)->i_vino.snap
 
-static inline u64 ceph_ino(struct inode *inode)
+static inline u64 ceph_ino(const struct inode *inode)
 {
 	return ceph_inode(inode)->i_vino.ino;
 }
 
-static inline u64 ceph_snap(struct inode *inode)
+static inline u64 ceph_snap(const struct inode *inode)
 {
 	return ceph_inode(inode)->i_vino.snap;
 }
@@ -818,7 +818,7 @@ static inline struct ceph_dentry_info *ceph_dentry(const struct dentry *dentry)
 /*
  * caps helpers
  */
-static inline bool __ceph_is_any_real_caps(struct ceph_inode_info *ci)
+static inline bool __ceph_is_any_real_caps(const struct ceph_inode_info *ci)
 {
 	return !RB_EMPTY_ROOT(&ci->i_caps);
 }
@@ -1076,7 +1076,7 @@ void ceph_umount_begin(struct super_block *sb);
  * a cap_snap is "pending" if it is still awaiting an in-progress
  * sync write (that may/may not still update size, mtime, etc.).
  */
-static inline bool __ceph_have_pending_cap_snap(struct ceph_inode_info *ci)
+static inline bool __ceph_have_pending_cap_snap(const struct ceph_inode_info *ci)
 {
 	return !list_empty(&ci->i_cap_snaps) &&
 	       list_last_entry(&ci->i_cap_snaps, struct ceph_cap_snap,
@@ -1173,7 +1173,7 @@ extern int ceph_getattr(struct mnt_idmap *idmap,
 			u32 request_mask, unsigned int flags);
 void ceph_inode_shutdown(struct inode *inode);
 
-static inline bool ceph_inode_is_shutdown(struct inode *inode)
+static inline bool ceph_inode_is_shutdown(const struct inode *inode)
 {
 	unsigned long flags = READ_ONCE(ceph_inode(inode)->i_ceph_flags);
 	struct ceph_fs_client *fsc = ceph_inode_to_fs_client(inode);
@@ -1357,7 +1357,7 @@ extern int ceph_pool_perm_check(struct inode *inode, int need);
 extern void ceph_pool_perm_destroy(struct ceph_mds_client* mdsc);
 int ceph_purge_inode_cap(struct inode *inode, struct ceph_cap *cap, bool *invalidate);
 
-static inline bool ceph_has_inline_data(struct ceph_inode_info *ci)
+static inline bool ceph_has_inline_data(const struct ceph_inode_info *ci)
 {
 	if (ci->i_inline_version == CEPH_INLINE_NONE ||
 	    ci->i_inline_version == 1) /* initial version, no data */
@@ -1432,7 +1432,7 @@ enum quota_get_realm {
 	QUOTA_GET_ANY
 };
 
-static inline bool __ceph_has_quota(struct ceph_inode_info *ci,
+static inline bool __ceph_has_quota(const struct ceph_inode_info *ci,
 				    enum quota_get_realm which)
 {
 	bool has_quota = false;
@@ -1465,7 +1465,7 @@ static inline void __ceph_update_quota(struct ceph_inode_info *ci,
 		ceph_adjust_quota_realms_count(&ci->netfs.inode, has_quota);
 }
 
-static inline int __ceph_sparse_read_ext_count(struct inode *inode, u64 len)
+static inline int __ceph_sparse_read_ext_count(const struct inode *inode, u64 len)
 {
 	int cnt = 0;
 
-- 
2.47.3

[PATCH v2 10/18] fs/ceph/super.h: add helper ceph_in_snap()

[Max Kellermann]

Some code simplification.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
---
 fs/ceph/acl.c        |  2 +-
 fs/ceph/addr.c       |  2 +-
 fs/ceph/dir.c        | 20 ++++++++++----------
 fs/ceph/export.c     |  8 ++++----
 fs/ceph/file.c       | 14 +++++++-------
 fs/ceph/inode.c      | 14 +++++++-------
 fs/ceph/mds_client.c | 10 +++++-----
 fs/ceph/quota.c      |  4 ++--
 fs/ceph/super.h      |  8 ++++++++
 fs/ceph/xattr.c      |  4 ++--
 10 files changed, 47 insertions(+), 39 deletions(-)

diff --git a/fs/ceph/acl.c b/fs/ceph/acl.c
index 85d3dd48b167..dbc64ab60308 100644
--- a/fs/ceph/acl.c
+++ b/fs/ceph/acl.c
@@ -99,7 +99,7 @@ int ceph_set_acl(struct mnt_idmap *idmap, struct dentry *dentry,
 	struct timespec64 old_ctime = inode_get_ctime(inode);
 	umode_t new_mode = inode->i_mode, old_mode = inode->i_mode;
 
-	if (ceph_snap(inode) != CEPH_NOSNAP) {
+	if (ceph_in_snap(inode)) {
 		ret = -EROFS;
 		goto out;
 	}
diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index 481654872e9f..d03639525eb8 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -2568,7 +2568,7 @@ int ceph_pool_perm_check(struct inode *inode, int need)
 	if (!S_ISREG(inode->i_mode))
 		return 0;
 
-	if (ci->i_vino.snap != CEPH_NOSNAP) {
+	if (ceph_in_snap(inode)) {
 		/*
 		 * Pool permission check needs to write to the first object.
 		 * But for snapshot, head of the first object may have already
diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index 27ce9e55e947..c297cc57f88c 100644
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -727,7 +727,7 @@ struct dentry *ceph_handle_snapdir(struct ceph_mds_request *req,
 	struct ceph_client *cl = ceph_inode_to_client(parent);
 
 	/* .snap dir? */
-	if (ceph_snap(parent) == CEPH_NOSNAP &&
+	if (!ceph_in_snap(parent) &&
 	    strcmp(dentry->d_name.name, fsc->mount_options->snapdir_name) == 0) {
 		struct dentry *res;
 		struct inode *inode = ceph_get_snapdir(parent);
@@ -919,7 +919,7 @@ static int ceph_mknod(struct mnt_idmap *idmap, struct inode *dir,
 	struct ceph_acl_sec_ctx as_ctx = {};
 	int err;
 
-	if (ceph_snap(dir) != CEPH_NOSNAP)
+	if (ceph_in_snap(dir))
 		return -EROFS;
 
 	err = ceph_wait_on_conflict_unlink(dentry);
@@ -1031,7 +1031,7 @@ static int ceph_symlink(struct mnt_idmap *idmap, struct inode *dir,
 	umode_t mode = S_IFLNK | 0777;
 	int err;
 
-	if (ceph_snap(dir) != CEPH_NOSNAP)
+	if (ceph_in_snap(dir))
 		return -EROFS;
 
 	err = ceph_wait_on_conflict_unlink(dentry);
@@ -1115,7 +1115,7 @@ static struct dentry *ceph_mkdir(struct mnt_idmap *idmap, struct inode *dir,
 		op = CEPH_MDS_OP_MKSNAP;
 		doutc(cl, "mksnap %llx.%llx/'%pd' dentry %p\n",
 		      ceph_vinop(dir), dentry, dentry);
-	} else if (ceph_snap(dir) == CEPH_NOSNAP) {
+	} else if (!ceph_in_snap(dir)) {
 		doutc(cl, "mkdir %llx.%llx/'%pd' dentry %p mode 0%ho\n",
 		      ceph_vinop(dir), dentry, dentry, mode);
 		op = CEPH_MDS_OP_MKDIR;
@@ -1202,7 +1202,7 @@ static int ceph_link(struct dentry *old_dentry, struct inode *dir,
 	if (err)
 		return err;
 
-	if (ceph_snap(dir) != CEPH_NOSNAP)
+	if (ceph_in_snap(dir))
 		return -EROFS;
 
 	err = fscrypt_prepare_link(old_dentry, dir, dentry);
@@ -1354,7 +1354,7 @@ static int ceph_unlink(struct inode *dir, struct dentry *dentry)
 		doutc(cl, "rmsnap %llx.%llx/'%pd' dn\n", ceph_vinop(dir),
 		      dentry);
 		op = CEPH_MDS_OP_RMSNAP;
-	} else if (ceph_snap(dir) == CEPH_NOSNAP) {
+	} else if (!ceph_in_snap(dir)) {
 		doutc(cl, "unlink/rmdir %llx.%llx/'%pd' inode %llx.%llx\n",
 		      ceph_vinop(dir), dentry, ceph_vinop(inode));
 		op = d_is_dir(dentry) ?
@@ -1483,7 +1483,7 @@ static int ceph_rename(struct mnt_idmap *idmap, struct inode *old_dir,
 
 	if (ceph_snap(old_dir) != ceph_snap(new_dir))
 		return -EXDEV;
-	if (ceph_snap(old_dir) != CEPH_NOSNAP) {
+	if (ceph_in_snap(old_dir)) {
 		if (old_dir == new_dir && ceph_snap(old_dir) == CEPH_SNAPDIR)
 			op = CEPH_MDS_OP_RENAMESNAP;
 		else
@@ -1981,7 +1981,7 @@ static int ceph_d_revalidate(struct inode *dir, const struct qstr *name,
 	mdsc = ceph_sb_to_fs_client(dir->i_sb)->mdsc;
 
 	/* always trust cached snapped dentries, snapdir dentry */
-	if (ceph_snap(dir) != CEPH_NOSNAP) {
+	if (ceph_in_snap(dir)) {
 		doutc(cl, "%p '%pd' inode %p is SNAPPED\n", dentry,
 		      dentry, inode);
 		valid = 1;
@@ -2065,7 +2065,7 @@ static int ceph_d_delete(const struct dentry *dentry)
 	/* won't release caps */
 	if (d_really_is_negative(dentry))
 		return 0;
-	if (ceph_snap(d_inode(dentry)) != CEPH_NOSNAP)
+	if (ceph_in_snap(d_inode(dentry)))
 		return 0;
 	/* valid lease? */
 	di = ceph_dentry(dentry);
@@ -2120,7 +2120,7 @@ static void ceph_d_prune(struct dentry *dentry)
 
 	/* we hold d_lock, so d_parent is stable */
 	dir_ci = ceph_inode(d_inode(dentry->d_parent));
-	if (dir_ci->i_vino.snap == CEPH_SNAPDIR)
+	if (ceph_in_snap(&dir_ci->netfs.inode))
 		return;
 
 	/* who calls d_delete() should also disable dcache readdir */
diff --git a/fs/ceph/export.c b/fs/ceph/export.c
index b2f2af104679..d132db40ba00 100644
--- a/fs/ceph/export.c
+++ b/fs/ceph/export.c
@@ -99,7 +99,7 @@ static int ceph_encode_fh(struct inode *inode, u32 *rawfh, int *max_len,
 	static const int connected_handle_length = CEPH_FH_WITH_PARENT_SIZE;
 	int type;
 
-	if (ceph_snap(inode) != CEPH_NOSNAP)
+	if (ceph_in_snap(inode))
 		return ceph_encode_snapfh(inode, rawfh, max_len, parent_inode);
 
 	if (parent_inode && (*max_len < connected_handle_length)) {
@@ -372,7 +372,7 @@ static struct dentry *ceph_get_parent(struct dentry *child)
 	struct ceph_client *cl = ceph_inode_to_client(inode);
 	struct dentry *dn;
 
-	if (ceph_snap(inode) != CEPH_NOSNAP) {
+	if (ceph_in_snap(inode)) {
 		struct inode* dir;
 		bool unlinked = false;
 		/* do not support non-directory */
@@ -456,7 +456,7 @@ static int __get_snap_name(struct dentry *parent, char *name,
 	if (ceph_ino(inode) != ceph_ino(dir))
 		goto out;
 	if (ceph_snap(inode) == CEPH_SNAPDIR) {
-		if (ceph_snap(dir) == CEPH_NOSNAP) {
+		if (!ceph_in_snap(dir)) {
 			/*
 			 * .get_name() from struct export_operations
 			 * assumes that its 'name' parameter is pointing
@@ -555,7 +555,7 @@ static int ceph_get_name(struct dentry *parent, char *name,
 	struct ceph_mds_reply_info_parsed *rinfo;
 	int err;
 
-	if (ceph_snap(inode) != CEPH_NOSNAP)
+	if (ceph_in_snap(inode))
 		return __get_snap_name(parent, name, child);
 
 	mdsc = ceph_inode_to_fs_client(inode)->mdsc;
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 71161f2b2151..d8859e4bed8b 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -437,7 +437,7 @@ int ceph_open(struct inode *inode, struct file *file)
 	}
 
 	/* snapped files are read-only */
-	if (ceph_snap(inode) != CEPH_NOSNAP && (file->f_mode & FMODE_WRITE))
+	if (ceph_in_snap(inode) && (file->f_mode & FMODE_WRITE))
 		return -EROFS;
 
 	/* trivially open snapdir */
@@ -469,7 +469,7 @@ int ceph_open(struct inode *inode, struct file *file)
 			ceph_check_caps(ci, 0);
 
 		return ceph_init_file(inode, file, fmode);
-	} else if (!do_sync && ceph_snap(inode) != CEPH_NOSNAP &&
+	} else if (!do_sync && ceph_in_snap(inode) &&
 		   (ci->i_snap_caps & wanted) == wanted) {
 		__ceph_touch_fmode(ci, mdsc, fmode);
 		spin_unlock(&ci->i_ceph_lock);
@@ -1539,7 +1539,7 @@ ceph_direct_read_write(struct kiocb *iocb, struct iov_iter *iter,
 	bool should_dirty = !write && user_backed_iter(iter);
 	bool sparse = ceph_test_mount_opt(fsc, SPARSEREAD);
 
-	if (write && ceph_snap(file_inode(file)) != CEPH_NOSNAP)
+	if (write && ceph_in_snap(file_inode(file)))
 		return -EROFS;
 
 	doutc(cl, "sync_direct_%s on file %p %lld~%u snapc %p seq %lld\n",
@@ -1775,7 +1775,7 @@ ceph_sync_write(struct kiocb *iocb, struct iov_iter *from, loff_t pos,
 	struct timespec64 mtime = current_time(inode);
 	size_t count = iov_iter_count(from);
 
-	if (ceph_snap(file_inode(file)) != CEPH_NOSNAP)
+	if (ceph_in_snap(file_inode(file)))
 		return -EROFS;
 
 	doutc(cl, "on file %p %lld~%u snapc %p seq %lld\n", file, pos,
@@ -2410,7 +2410,7 @@ static ssize_t ceph_write_iter(struct kiocb *iocb, struct iov_iter *from)
 	if (ceph_inode_is_shutdown(inode))
 		return -ESTALE;
 
-	if (ceph_snap(inode) != CEPH_NOSNAP)
+	if (ceph_in_snap(inode))
 		return -EROFS;
 
 	prealloc_cf = ceph_alloc_cap_flush();
@@ -2762,7 +2762,7 @@ static long ceph_fallocate(struct file *file, int mode,
 
 	inode_lock(inode);
 
-	if (ceph_snap(inode) != CEPH_NOSNAP) {
+	if (ceph_in_snap(inode)) {
 		ret = -EROFS;
 		goto unlock;
 	}
@@ -3051,7 +3051,7 @@ static ssize_t __ceph_copy_file_range(struct file *src_file, loff_t src_off,
 			return -EXDEV;
 		}
 	}
-	if (ceph_snap(dst_inode) != CEPH_NOSNAP)
+	if (ceph_in_snap(dst_inode))
 		return -EROFS;
 
 	/*
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index 1f65aa387008..aba98975a8a3 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -766,7 +766,7 @@ void ceph_evict_inode(struct inode *inode)
 	 * caps in i_snap_caps.
 	 */
 	if (ci->i_snap_realm) {
-		if (ceph_snap(inode) == CEPH_NOSNAP) {
+		if (!ceph_in_snap(inode)) {
 			doutc(cl, " dropping residual ref to snap realm %p\n",
 			      ci->i_snap_realm);
 			ceph_change_snap_realm(inode, NULL);
@@ -1066,7 +1066,7 @@ int ceph_fill_inode(struct inode *inode, struct page *locked_page,
 	info_caps = le32_to_cpu(info->cap.caps);
 
 	/* prealloc new cap struct */
-	if (info_caps && ceph_snap(inode) == CEPH_NOSNAP) {
+	if (info_caps && !ceph_in_snap(inode)) {
 		new_cap = ceph_get_cap(mdsc, caps_reservation);
 		if (!new_cap)
 			return -ENOMEM;
@@ -1088,7 +1088,7 @@ int ceph_fill_inode(struct inode *inode, struct page *locked_page,
 		pool_ns = ceph_find_or_create_string(iinfo->pool_ns_data,
 						     iinfo->pool_ns_len);
 
-	if (ceph_snap(inode) != CEPH_NOSNAP && !ci->i_snapid_map)
+	if (ceph_in_snap(inode) && !ci->i_snapid_map)
 		ci->i_snapid_map = ceph_get_snapid_map(mdsc, ceph_snap(inode));
 
 	spin_lock(&ci->i_ceph_lock);
@@ -1333,7 +1333,7 @@ int ceph_fill_inode(struct inode *inode, struct page *locked_page,
 
 	/* were we issued a capability? */
 	if (info_caps) {
-		if (ceph_snap(inode) == CEPH_NOSNAP) {
+		if (!ceph_in_snap(inode)) {
 			ceph_add_cap(inode, session,
 				     le64_to_cpu(info->cap.cap_id),
 				     info_caps,
@@ -1433,7 +1433,7 @@ static void __update_dentry_lease(struct inode *dir, struct dentry *dentry,
 	doutc(cl, "%p duration %lu ms ttl %lu\n", dentry, duration, ttl);
 
 	/* only track leases on regular dentries */
-	if (ceph_snap(dir) != CEPH_NOSNAP)
+	if (ceph_in_snap(dir))
 		return;
 
 	if (mask & CEPH_LEASE_PRIMARY_LINK)
@@ -2930,7 +2930,7 @@ int ceph_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
 	struct ceph_fs_client *fsc = ceph_inode_to_fs_client(inode);
 	int err;
 
-	if (ceph_snap(inode) != CEPH_NOSNAP)
+	if (ceph_in_snap(inode))
 		return -EROFS;
 
 	if (ceph_inode_is_shutdown(inode))
@@ -3185,7 +3185,7 @@ int ceph_getattr(struct mnt_idmap *idmap, const struct path *path,
 		valid_mask |= STATX_CHANGE_COOKIE;
 	}
 
-	if (ceph_snap(inode) == CEPH_NOSNAP)
+	if (!ceph_in_snap(inode))
 		stat->dev = sb->s_dev;
 	else
 		stat->dev = ci->i_snapid_map ? ci->i_snapid_map->dev : 0;
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 853bf698b356..540e1ad9ea77 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -1310,7 +1310,7 @@ static struct inode *get_nonsnap_parent(struct dentry *dentry)
 
 	while (dentry && !IS_ROOT(dentry)) {
 		inode = d_inode_rcu(dentry);
-		if (!inode || ceph_snap(inode) == CEPH_NOSNAP)
+		if (!inode || !ceph_in_snap(inode))
 			break;
 		dentry = dentry->d_parent;
 	}
@@ -1384,7 +1384,7 @@ static int __choose_mds(struct ceph_mds_client *mdsc,
 			inode = d_inode(req->r_dentry);
 			if (inode)
 				ihold(inode);
-		} else if (ceph_snap(dir) != CEPH_NOSNAP) {
+		} else if (ceph_in_snap(dir)) {
 			/* direct snapped/virtual snapdir requests
 			 * based on parent dir inode */
 			inode = get_nonsnap_parent(parent);
@@ -2877,7 +2877,7 @@ char *ceph_mdsc_build_path(struct ceph_mds_client *mdsc, struct dentry *dentry,
 			spin_unlock(&cur->d_lock);
 			parent = dget_parent(cur);
 		} else if (for_wire && inode && dentry != cur &&
-			   ceph_snap(inode) == CEPH_NOSNAP) {
+			   !ceph_in_snap(inode)) {
 			spin_unlock(&cur->d_lock);
 			pos++; /* get rid of any prepended '/' */
 			break;
@@ -2986,7 +2986,7 @@ static int build_dentry_path(struct ceph_mds_client *mdsc, struct dentry *dentry
 	rcu_read_lock();
 	if (!dir)
 		dir = d_inode_rcu(dentry->d_parent);
-	if (dir && parent_locked && ceph_snap(dir) == CEPH_NOSNAP &&
+	if (dir && parent_locked && !ceph_in_snap(dir) &&
 	    !IS_ENCRYPTED(dir)) {
 		path_info->vino.ino = ceph_ino(dir);
 		path_info->vino.snap = ceph_snap(dir);
@@ -3012,7 +3012,7 @@ static int build_inode_path(struct inode *inode, struct ceph_path_info *path_inf
 	struct dentry *dentry;
 	char *path;
 
-	if (ceph_snap(inode) == CEPH_NOSNAP) {
+	if (!ceph_in_snap(inode)) {
 		path_info->vino.ino = ceph_ino(inode);
 		path_info->vino.snap = ceph_snap(inode);
 		path_info->pathlen = 0;
diff --git a/fs/ceph/quota.c b/fs/ceph/quota.c
index 053d5bf0c9f0..08641d578a0b 100644
--- a/fs/ceph/quota.c
+++ b/fs/ceph/quota.c
@@ -223,7 +223,7 @@ static int get_quota_realm(struct ceph_mds_client *mdsc, struct inode *inode,
 
 	if (realmp)
 		*realmp = NULL;
-	if (ceph_snap(inode) != CEPH_NOSNAP)
+	if (ceph_in_snap(inode))
 		return 0;
 
 restart:
@@ -341,7 +341,7 @@ static bool check_quota_exceeded(struct inode *inode, enum quota_check_op op,
 	u64 max, rvalue;
 	bool exceeded = false;
 
-	if (ceph_snap(inode) != CEPH_NOSNAP)
+	if (ceph_in_snap(inode))
 		return false;
 
 	down_read(&mdsc->snap_rwsem);
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index ab6fa8319c79..b0b8d04b594f 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -608,6 +608,14 @@ static inline u64 ceph_snap(const struct inode *inode)
 	return ceph_inode(inode)->i_vino.snap;
 }
 
+/**
+ * Is this inode in a ".snap" directory?
+ */
+static inline bool ceph_in_snap(const struct inode *inode)
+{
+	return ceph_snap(inode) != CEPH_NOSNAP;
+}
+
 /**
  * ceph_present_ino - format an inode number for presentation to userland
  * @sb: superblock where the inode lives
diff --git a/fs/ceph/xattr.c b/fs/ceph/xattr.c
index 124dde705e79..af54480d9254 100644
--- a/fs/ceph/xattr.c
+++ b/fs/ceph/xattr.c
@@ -270,7 +270,7 @@ static bool ceph_vxattrcb_quota_exists(struct ceph_inode_info *ci)
 	bool ret = false;
 	spin_lock(&ci->i_ceph_lock);
 	if ((ci->i_max_files || ci->i_max_bytes) &&
-	    ci->i_vino.snap == CEPH_NOSNAP &&
+	    !ceph_in_snap(&ci->netfs.inode) &&
 	    ci->i_snap_realm &&
 	    ci->i_snap_realm->ino == ci->i_vino.ino)
 		ret = true;
@@ -1193,7 +1193,7 @@ int __ceph_setxattr(struct inode *inode, const char *name,
 	bool check_realm = false;
 	bool lock_snap_rwsem = false;
 
-	if (ceph_snap(inode) != CEPH_NOSNAP)
+	if (ceph_in_snap(inode))
 		return -EROFS;
 
 	vxattr = ceph_match_vxattr(inode, name);
-- 
2.47.3

[PATCH v2 11/18] fs/ceph: use ceph_vino() etc. instead of accessing i_vino directly

[Max Kellermann]

Prepare to remove (optimize) `i_vino`.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
---
 fs/ceph/addr.c       |  5 ++---
 fs/ceph/caps.c       |  4 ++--
 fs/ceph/file.c       | 14 +++++++-------
 fs/ceph/mds_client.c |  2 +-
 fs/ceph/quota.c      |  2 +-
 fs/ceph/snap.c       |  4 ++--
 fs/ceph/super.h      |  7 +++----
 fs/ceph/xattr.c      |  4 ++--
 8 files changed, 20 insertions(+), 22 deletions(-)

diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index d03639525eb8..f627f2e28b9b 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -282,7 +282,6 @@ static bool ceph_netfs_issue_op_inline(struct netfs_io_subrequest *subreq)
 	struct ceph_mds_reply_info_in *iinfo;
 	struct ceph_mds_request *req;
 	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(inode->i_sb);
-	struct ceph_inode_info *ci = ceph_inode(inode);
 	ssize_t err = 0;
 	size_t len;
 	int mode;
@@ -302,7 +301,7 @@ static bool ceph_netfs_issue_op_inline(struct netfs_io_subrequest *subreq)
 		err = PTR_ERR(req);
 		goto out;
 	}
-	req->r_ino1 = ci->i_vino;
+	req->r_ino1 = ceph_vino(inode);
 	req->r_args.getattr.mask = cpu_to_le32(CEPH_STAT_CAP_INLINE_DATA);
 	req->r_num_caps = 2;
 
@@ -2466,7 +2465,7 @@ static int __ceph_pool_perm_get(struct ceph_inode_info *ci,
 	rd_req->r_base_oloc.pool = pool;
 	if (pool_ns)
 		rd_req->r_base_oloc.pool_ns = ceph_get_string(pool_ns);
-	ceph_oid_printf(&rd_req->r_base_oid, "%llx.00000000", ci->i_vino.ino);
+	ceph_oid_printf(&rd_req->r_base_oid, "%llx.00000000", ceph_ino(&ci->netfs.inode));
 
 	err = ceph_osdc_alloc_messages(rd_req, GFP_NOFS);
 	if (err)
diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 372b239f6a36..00ef37312a79 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -730,7 +730,7 @@ void ceph_add_cap(struct inode *inode,
 			ceph_change_snap_realm(inode, realm);
 		else
 			WARN(1, "%s: couldn't find snap realm 0x%llx (ino 0x%llx oldrealm 0x%llx)\n",
-			     __func__, realmino, ci->i_vino.ino,
+			     __func__, realmino, ceph_ino(inode),
 			     ci->i_snap_realm ? ci->i_snap_realm->ino : 0);
 	}
 
@@ -1176,7 +1176,7 @@ void __ceph_remove_cap(struct ceph_cap *cap, bool queue_release)
 	} else {
 		cap->queue_release = 0;
 	}
-	cap->cap_ino = ci->i_vino.ino;
+	cap->cap_ino = ceph_ino(inode);
 
 	spin_unlock(&session->s_cap_lock);
 
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index d8859e4bed8b..7a6bff86b750 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -1118,7 +1118,7 @@ ssize_t __ceph_sync_read(struct inode *inode, loff_t *ki_pos,
 		      read_off, read_len);
 
 		req = ceph_osdc_new_request(osdc, &ci->i_layout,
-					ci->i_vino, read_off, &read_len, 0, 1,
+					ceph_vino(inode), read_off, &read_len, 0, 1,
 					sparse ? CEPH_OSD_OP_SPARSE_READ :
 						 CEPH_OSD_OP_READ,
 					CEPH_OSD_FLAG_READ,
@@ -1824,7 +1824,7 @@ ceph_sync_write(struct kiocb *iocb, struct iov_iter *from, loff_t pos,
 		rmw = first || last;
 
 		doutc(cl, "ino %llx %lld~%llu adjusted %lld~%llu -- %srmw\n",
-		      ci->i_vino.ino, pos, len, write_pos, write_len,
+		      ceph_ino(inode), pos, len, write_pos, write_len,
 		      rmw ? "" : "no ");
 
 		/*
@@ -1857,7 +1857,7 @@ ceph_sync_write(struct kiocb *iocb, struct iov_iter *from, loff_t pos,
 			 * depending on how the request was aligned.
 			 */
 			req = ceph_osdc_new_request(osdc, &ci->i_layout,
-					ci->i_vino, first ? first_pos : last_pos,
+					ceph_vino(inode), first ? first_pos : last_pos,
 					&read_len, 0, (first && last) ? 2 : 1,
 					CEPH_OSD_OP_SPARSE_READ, CEPH_OSD_FLAG_READ,
 					NULL, ci->i_truncate_seq,
@@ -2055,7 +2055,7 @@ ceph_sync_write(struct kiocb *iocb, struct iov_iter *from, loff_t pos,
 		}
 
 		req = ceph_osdc_new_request(osdc, &ci->i_layout,
-					    ci->i_vino, write_pos, &write_len,
+					    ceph_vino(inode), write_pos, &write_len,
 					    rmw ? 1 : 0, rmw ? 2 : 1,
 					    CEPH_OSD_OP_WRITE,
 					    CEPH_OSD_FLAG_WRITE,
@@ -2980,12 +2980,12 @@ static ssize_t ceph_do_objects_copy(struct ceph_inode_info *src_ci, u64 *src_off
 					      &dst_objoff, &dst_objlen);
 		ceph_oid_init(&src_oid);
 		ceph_oid_printf(&src_oid, "%llx.%08llx",
-				src_ci->i_vino.ino, src_objnum);
+				ceph_ino(&src_ci->netfs.inode), src_objnum);
 		ceph_oid_init(&dst_oid);
 		ceph_oid_printf(&dst_oid, "%llx.%08llx",
-				dst_ci->i_vino.ino, dst_objnum);
+				ceph_ino(&dst_ci->netfs.inode), dst_objnum);
 		/* Do an object remote copy */
-		req = ceph_alloc_copyfrom_request(osdc, src_ci->i_vino.snap,
+		req = ceph_alloc_copyfrom_request(osdc, ceph_snap(&src_ci->netfs.inode),
 						  &src_oid, &src_oloc,
 						  &dst_oid, &dst_oloc,
 						  dst_ci->i_truncate_seq,
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 540e1ad9ea77..b4a1c126cbc9 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -1988,7 +1988,7 @@ static void remove_session_caps(struct ceph_mds_session *session)
 			if (cap == prev)
 				break;
 			prev = cap;
-			vino = cap->ci->i_vino;
+			vino = ceph_vino(&cap->ci->netfs.inode);
 			spin_unlock(&session->s_cap_lock);
 
 			inode = ceph_find_inode(sb, vino);
diff --git a/fs/ceph/quota.c b/fs/ceph/quota.c
index 08641d578a0b..02d7a3062f2d 100644
--- a/fs/ceph/quota.c
+++ b/fs/ceph/quota.c
@@ -31,7 +31,7 @@ static inline bool ceph_has_realms_with_quotas(struct inode *inode)
 	if (root && ceph_ino(root) == CEPH_INO_ROOT)
 		return false;
 	/* MDS stray dirs have no quota realms */
-	if (ceph_vino_is_reserved(ceph_inode(inode)->i_vino))
+	if (ceph_vino_is_reserved(ceph_vino(inode)))
 		return false;
 	/* otherwise, we can't know for sure */
 	return true;
diff --git a/fs/ceph/snap.c b/fs/ceph/snap.c
index 94964e0952bd..f064b5ad3bf4 100644
--- a/fs/ceph/snap.c
+++ b/fs/ceph/snap.c
@@ -985,7 +985,7 @@ void ceph_change_snap_realm(struct inode *inode, struct ceph_snap_realm *realm)
 	if (oldrealm) {
 		spin_lock(&oldrealm->inodes_with_caps_lock);
 		list_del_init(&ci->i_snap_realm_item);
-		if (oldrealm->ino == ci->i_vino.ino)
+		if (oldrealm->ino == ceph_ino(inode))
 			oldrealm->inode = NULL;
 		spin_unlock(&oldrealm->inodes_with_caps_lock);
 		ceph_put_snap_realm(mdsc, oldrealm);
@@ -996,7 +996,7 @@ void ceph_change_snap_realm(struct inode *inode, struct ceph_snap_realm *realm)
 	if (realm) {
 		spin_lock(&realm->inodes_with_caps_lock);
 		list_add(&ci->i_snap_realm_item, &realm->inodes_with_caps);
-		if (realm->ino == ci->i_vino.ino)
+		if (realm->ino == ceph_ino(inode))
 			realm->inode = inode;
 		spin_unlock(&realm->inodes_with_caps_lock);
 	}
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index b0b8d04b594f..660125d94f8e 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -596,7 +596,7 @@ static inline ino_t ceph_vino_to_ino_t(const struct ceph_vino vino)
 }
 
 /* for printf-style formatting */
-#define ceph_vinop(i) ceph_inode(i)->i_vino.ino, ceph_inode(i)->i_vino.snap
+#define ceph_vinop(i) ceph_ino(i), ceph_snap(i)
 
 static inline u64 ceph_ino(const struct inode *inode)
 {
@@ -641,9 +641,8 @@ static inline u64 ceph_present_inode(struct inode *inode)
 static inline int ceph_ino_compare(struct inode *inode, void *data)
 {
 	struct ceph_vino *pvino = (struct ceph_vino *)data;
-	struct ceph_inode_info *ci = ceph_inode(inode);
-	return ci->i_vino.ino == pvino->ino &&
-		ci->i_vino.snap == pvino->snap;
+	return ceph_ino(inode) == pvino->ino &&
+		ceph_snap(inode) == pvino->snap;
 }
 
 /*
diff --git a/fs/ceph/xattr.c b/fs/ceph/xattr.c
index af54480d9254..b8416afd4901 100644
--- a/fs/ceph/xattr.c
+++ b/fs/ceph/xattr.c
@@ -272,7 +272,7 @@ static bool ceph_vxattrcb_quota_exists(struct ceph_inode_info *ci)
 	if ((ci->i_max_files || ci->i_max_bytes) &&
 	    !ceph_in_snap(&ci->netfs.inode) &&
 	    ci->i_snap_realm &&
-	    ci->i_snap_realm->ino == ci->i_vino.ino)
+	    ci->i_snap_realm->ino == ceph_ino(&ci->netfs.inode))
 		ret = true;
 	spin_unlock(&ci->i_ceph_lock);
 	return ret;
@@ -1328,7 +1328,7 @@ int __ceph_setxattr(struct inode *inode, const char *name,
 			spin_lock(&ci->i_ceph_lock);
 			if ((ci->i_max_files || ci->i_max_bytes) &&
 			    !(ci->i_snap_realm &&
-			      ci->i_snap_realm->ino == ci->i_vino.ino))
+			      ci->i_snap_realm->ino == ceph_ino(&ci->netfs.inode)))
 				err = -EOPNOTSUPP;
 			spin_unlock(&ci->i_ceph_lock);
 		}
-- 
2.47.3

[PATCH v2 12/18] fs/ceph: remove redundant inode number from ceph_inode_info

[Max Kellermann]

On 64 bit systems, ceph_vino_to_ino_t() is a no-op, and inode.i_ino is
the same as ceph_vino.ino.

This reduces the size of `struct ceph_inode_info` by 8 bytes.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
---
 fs/ceph/cache.c |  4 +++-
 fs/ceph/inode.c |  7 +++++++
 fs/ceph/super.h | 23 +++++++++++++++++++++++
 3 files changed, 33 insertions(+), 1 deletion(-)

diff --git a/fs/ceph/cache.c b/fs/ceph/cache.c
index f678bab189d8..289615e58196 100644
--- a/fs/ceph/cache.c
+++ b/fs/ceph/cache.c
@@ -16,6 +16,7 @@ void ceph_fscache_register_inode_cookie(struct inode *inode)
 {
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	struct ceph_fs_client *fsc = ceph_inode_to_fs_client(inode);
+	struct ceph_vino vino;
 
 	/* No caching for filesystem? */
 	if (!fsc->fscache)
@@ -31,9 +32,10 @@ void ceph_fscache_register_inode_cookie(struct inode *inode)
 
 	WARN_ON_ONCE(ci->netfs.cache);
 
+	vino = ceph_vino(inode);
 	ci->netfs.cache =
 		fscache_acquire_cookie(fsc->fscache, 0,
-				       &ci->i_vino, sizeof(ci->i_vino),
+				       &vino, sizeof(vino),
 				       &ci->i_version, sizeof(ci->i_version),
 				       i_size_read(inode));
 	if (ci->netfs.cache)
diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index aba98975a8a3..e82877782601 100644
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -44,11 +44,18 @@ static void ceph_inode_work(struct work_struct *work);
  */
 static int ceph_set_ino_cb(struct inode *inode, void *data)
 {
+	const struct ceph_vino *vino = data;
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(inode->i_sb);
 
+#if BITS_PER_LONG >= 64
+	inode->i_ino = vino->ino;
+	ci->i_snap = vino->snap;
+#else
 	ci->i_vino = *(struct ceph_vino *)data;
 	inode->i_ino = ceph_vino_to_ino_t(ci->i_vino);
+#endif
+
 	inode_set_iversion_raw(inode, 0);
 	percpu_counter_inc(&mdsc->metric.total_inodes);
 
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 660125d94f8e..e5ab1b83a84d 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -378,7 +378,15 @@ struct ceph_inode_xattrs_info {
  */
 struct ceph_inode_info {
 	struct netfs_inode netfs; /* Netfslib context and vfs inode */
+
+#if BITS_PER_LONG >= 64
+	/* on 64 bit systems, the full Ceph inode number is stored in
+	 * netfs.inode.i_ino
+	 */
+	u64 i_snap;
+#else
 	struct ceph_vino i_vino;   /* ceph ino + snap */
+#endif
 
 	spinlock_t i_ceph_lock;
 
@@ -570,7 +578,14 @@ ceph_inode_to_client(const struct inode *inode)
 static inline struct ceph_vino
 ceph_vino(const struct inode *inode)
 {
+#if BITS_PER_LONG >= 64
+	return (struct ceph_vino){
+		.ino = inode->i_ino,
+		.snap = ceph_inode(inode)->i_snap,
+	};
+#else
 	return ceph_inode(inode)->i_vino;
+#endif
 }
 
 static inline u32 ceph_ino_to_ino32(u64 vino)
@@ -600,12 +615,20 @@ static inline ino_t ceph_vino_to_ino_t(const struct ceph_vino vino)
 
 static inline u64 ceph_ino(const struct inode *inode)
 {
+#if BITS_PER_LONG >= 64
+	return inode->i_ino;
+#else
 	return ceph_inode(inode)->i_vino.ino;
+#endif
 }
 
 static inline u64 ceph_snap(const struct inode *inode)
 {
+#if BITS_PER_LONG >= 64
+	return ceph_inode(inode)->i_snap;
+#else
 	return ceph_inode(inode)->i_vino.snap;
+#endif
 }
 
 /**
-- 
2.47.3

[PATCH v2 13/18] fs/ceph: remove unused field `ceph_cap.last_used`

[Max Kellermann]

This reduces the size of `struct ceph_cap` by 8 bytes.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
---
 fs/ceph/super.h | 1 -
 1 file changed, 1 deletion(-)

diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index e5ab1b83a84d..4916faf54915 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -224,7 +224,6 @@ struct ceph_cap {
 	};
 	u32 seq, issue_seq, mseq;
 	u32 cap_gen;      /* active/stale cycle */
-	unsigned long last_used;
 	struct list_head caps_item;
 };
 
-- 
2.47.3

[PATCH v2 14/18] fs/ceph: convert ceph_cap.queue_release to bool

[Max Kellermann]

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
---
 fs/ceph/caps.c  | 6 +++---
 fs/ceph/super.h | 2 +-
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 00ef37312a79..7b0125d6df0b 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -1168,13 +1168,13 @@ void __ceph_remove_cap(struct ceph_cap *cap, bool queue_release)
 	if (queue_release &&
 	    (!session->s_cap_reconnect ||
 	     cap->cap_gen == atomic_read(&session->s_cap_gen))) {
-		cap->queue_release = 1;
+		cap->queue_release = true;
 		if (removed) {
 			__ceph_queue_cap_release(session, cap);
 			removed = 0;
 		}
 	} else {
-		cap->queue_release = 0;
+		cap->queue_release = false;
 	}
 	cap->cap_ino = ceph_ino(inode);
 
@@ -4593,7 +4593,7 @@ void ceph_handle_caps(struct ceph_mds_session *session,
 	if (do_cap_release) {
 		cap = ceph_get_cap(mdsc, NULL);
 		cap->cap_ino = vino.ino;
-		cap->queue_release = 1;
+		cap->queue_release = true;
 		cap->cap_id = le64_to_cpu(h->cap_id);
 		cap->mseq = mseq;
 		cap->seq = seq;
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 4916faf54915..abe403eff0bb 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -219,7 +219,7 @@ struct ceph_cap {
 		/* caps to release */
 		struct {
 			u64 cap_ino;
-			int queue_release;
+			bool queue_release;
 		};
 	};
 	u32 seq, issue_seq, mseq;
-- 
2.47.3

[PATCH v2 15/18] fs/ceph/super: move `ceph_cap.caps_item` into the union

[Max Kellermann]

The `caps_item` field is only used if the `ceph_cap` object is
"reserved", i.e. when it is in the `ceph_mds_client.caps_list` list
(but is otherwise uninitialized).

This reduces the size of the struct by 16 bytes.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
---
 fs/ceph/super.h | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index abe403eff0bb..afe681a47f71 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -208,6 +208,14 @@ struct ceph_cap {
 	struct list_head session_caps;   /* per-session caplist */
 	u64 cap_id;       /* unique cap id (mds provided) */
 	union {
+		/* reserved caps */
+		struct {
+			/**
+			 * For the `ceph_mds_client.caps_list` list.
+			 * Protected by `caps_list_lock`.
+			 */
+			struct list_head caps_item;
+		};
 		/* in-use caps */
 		struct {
 			int issued;       /* latest, from the mds */
@@ -224,7 +232,6 @@ struct ceph_cap {
 	};
 	u32 seq, issue_seq, mseq;
 	u32 cap_gen;      /* active/stale cycle */
-	struct list_head caps_item;
 };
 
 #define CHECK_CAPS_AUTHONLY     1  /* only check auth cap */
-- 
2.47.3

[PATCH v2 16/18] fs/ceph/snap: add a kmem_cache for struct ceph_snap_realm

[Max Kellermann]

There will be lots of ceph_snap_realm instances, and having a separate
kmem_cache seems worthwile.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
---
 fs/ceph/snap.c               | 4 ++--
 fs/ceph/super.c              | 9 +++++++++
 include/linux/ceph/libceph.h | 1 +
 3 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/fs/ceph/snap.c b/fs/ceph/snap.c
index f064b5ad3bf4..12f80df4b651 100644
--- a/fs/ceph/snap.c
+++ b/fs/ceph/snap.c
@@ -118,7 +118,7 @@ static struct ceph_snap_realm *ceph_create_snap_realm(
 
 	lockdep_assert_held_write(&mdsc->snap_rwsem);
 
-	realm = kzalloc_obj(*realm, GFP_NOFS);
+	realm = kmem_cache_zalloc(ceph_snap_realm_cachep, GFP_NOFS);
 	if (!realm)
 		return ERR_PTR(-ENOMEM);
 
@@ -205,7 +205,7 @@ static void __destroy_snap_realm(struct ceph_mds_client *mdsc,
 	kfree(realm->prior_parent_snaps);
 	kfree(realm->snaps);
 	ceph_put_snap_context(realm->cached_context);
-	kfree(realm);
+	kmem_cache_free(ceph_snap_realm_cachep, realm);
 }
 
 /*
diff --git a/fs/ceph/super.c b/fs/ceph/super.c
index c05fbd4237f8..73c316c23315 100644
--- a/fs/ceph/super.c
+++ b/fs/ceph/super.c
@@ -910,6 +910,7 @@ struct kmem_cache *ceph_inode_cachep;
 struct kmem_cache *ceph_cap_cachep;
 struct kmem_cache *ceph_cap_snap_cachep;
 struct kmem_cache *ceph_cap_flush_cachep;
+struct kmem_cache *ceph_snap_realm_cachep;
 struct kmem_cache *ceph_dentry_cachep;
 struct kmem_cache *ceph_file_cachep;
 struct kmem_cache *ceph_dir_file_cachep;
@@ -945,6 +946,11 @@ static int __init init_caches(void)
 	if (!ceph_cap_flush_cachep)
 		goto bad_cap_flush;
 
+	ceph_snap_realm_cachep = KMEM_CACHE(ceph_snap_realm,
+					    SLAB_RECLAIM_ACCOUNT);
+	if (!ceph_snap_realm_cachep)
+		goto bad_snap_realm;
+
 	ceph_dentry_cachep = KMEM_CACHE(ceph_dentry_info,
 					SLAB_RECLAIM_ACCOUNT);
 	if (!ceph_dentry_cachep)
@@ -984,6 +990,8 @@ static int __init init_caches(void)
 bad_file:
 	kmem_cache_destroy(ceph_dentry_cachep);
 bad_dentry:
+	kmem_cache_destroy(ceph_snap_realm_cachep);
+bad_snap_realm:
 	kmem_cache_destroy(ceph_cap_flush_cachep);
 bad_cap_flush:
 	kmem_cache_destroy(ceph_cap_snap_cachep);
@@ -1006,6 +1014,7 @@ static void destroy_caches(void)
 	kmem_cache_destroy(ceph_cap_cachep);
 	kmem_cache_destroy(ceph_cap_snap_cachep);
 	kmem_cache_destroy(ceph_cap_flush_cachep);
+	kmem_cache_destroy(ceph_snap_realm_cachep);
 	kmem_cache_destroy(ceph_dentry_cachep);
 	kmem_cache_destroy(ceph_file_cachep);
 	kmem_cache_destroy(ceph_dir_file_cachep);
diff --git a/include/linux/ceph/libceph.h b/include/linux/ceph/libceph.h
index 63e0e2aa1ce9..379629cafbce 100644
--- a/include/linux/ceph/libceph.h
+++ b/include/linux/ceph/libceph.h
@@ -276,6 +276,7 @@ extern struct kmem_cache *ceph_inode_cachep;
 extern struct kmem_cache *ceph_cap_cachep;
 extern struct kmem_cache *ceph_cap_snap_cachep;
 extern struct kmem_cache *ceph_cap_flush_cachep;
+extern struct kmem_cache *ceph_snap_realm_cachep;
 extern struct kmem_cache *ceph_dentry_cachep;
 extern struct kmem_cache *ceph_file_cachep;
 extern struct kmem_cache *ceph_dir_file_cachep;
-- 
2.47.3

[PATCH v2 17/18] fs/ceph/super: reorder struct ceph_snap_realm fields

[Max Kellermann]

This eliminates two padding hole and reduces the size of the struct by
16 bytes.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
---
 fs/ceph/super.h | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index afe681a47f71..ca4db56ef2d0 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -1020,16 +1020,16 @@ struct ceph_readdir_cache_control {
 struct ceph_snap_realm {
 	u64 ino;
 	struct inode *inode;
-	atomic_t nref;
 	struct rb_node node;
 
 	u64 created, seq;
 	u64 parent_ino;
 	u64 parent_since;   /* snapid when our current parent became so */
 
-	u64 *prior_parent_snaps;      /* snaps inherited from any parents we */
-	u32 num_prior_parent_snaps;   /*  had prior to parent_since */
+	u64 *prior_parent_snaps;      /* snaps inherited from any parents we had prior to parent_since */
 	u64 *snaps;                   /* snaps specific to this realm */
+
+	u32 num_prior_parent_snaps;
 	u32 num_snaps;
 
 	struct ceph_snap_realm *parent;
@@ -1047,6 +1047,8 @@ struct ceph_snap_realm {
 
 	struct list_head inodes_with_caps;
 	spinlock_t inodes_with_caps_lock;
+
+	atomic_t nref;
 };
 
 static inline int default_congestion_kb(void)
-- 
2.47.3

[PATCH v2 18/18] fs/ceph/super: remove redundant field `ceph_snap_realm.parent_ino`

[Max Kellermann]

This reduces the size of the struct by another 8 bytes.

Signed-off-by: Max Kellermann <max.kellermann@ionos.com>
---
 fs/ceph/mds_client.c | 4 ++--
 fs/ceph/snap.c       | 5 ++---
 fs/ceph/super.h      | 1 -
 3 files changed, 4 insertions(+), 6 deletions(-)

diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index b4a1c126cbc9..f0b9d653ffd1 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -5044,10 +5044,10 @@ static int encode_snap_realms(struct ceph_mds_client *mdsc,
 		}
 
 		doutc(cl, " adding snap realm %llx seq %lld parent %llx\n",
-		      realm->ino, realm->seq, realm->parent_ino);
+		      realm->ino, realm->seq, realm->parent ? realm->parent->ino : 0);
 		sr_rec.ino = cpu_to_le64(realm->ino);
 		sr_rec.seq = cpu_to_le64(realm->seq);
-		sr_rec.parent = cpu_to_le64(realm->parent_ino);
+		sr_rec.parent = cpu_to_le64(realm->parent ? realm->parent->ino : 0);
 
 		err = ceph_pagelist_append(pagelist, &sr_rec, sizeof(sr_rec));
 		if (err)
diff --git a/fs/ceph/snap.c b/fs/ceph/snap.c
index 12f80df4b651..a5f8f3f95f3b 100644
--- a/fs/ceph/snap.c
+++ b/fs/ceph/snap.c
@@ -297,7 +297,7 @@ static int adjust_snap_realm_parent(struct ceph_mds_client *mdsc,
 
 	lockdep_assert_held_write(&mdsc->snap_rwsem);
 
-	if (realm->parent_ino == parentino)
+	if (realm->parent && realm->parent->ino == parentino)
 		return 0;
 
 	parent = ceph_lookup_snap_realm(mdsc, parentino);
@@ -307,12 +307,11 @@ static int adjust_snap_realm_parent(struct ceph_mds_client *mdsc,
 			return PTR_ERR(parent);
 	}
 	doutc(cl, "%llx %p: %llx %p -> %llx %p\n", realm->ino, realm,
-	      realm->parent_ino, realm->parent, parentino, parent);
+	      realm->parent ? realm->parent->ino : 0, realm->parent, parentino, parent);
 	if (realm->parent) {
 		list_del_init(&realm->child_item);
 		ceph_put_snap_realm(mdsc, realm->parent);
 	}
-	realm->parent_ino = parentino;
 	realm->parent = parent;
 	list_add(&realm->child_item, &parent->children);
 	return 1;
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index ca4db56ef2d0..86a5929ee5d2 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -1023,7 +1023,6 @@ struct ceph_snap_realm {
 	struct rb_node node;
 
 	u64 created, seq;
-	u64 parent_ino;
 	u64 parent_since;   /* snapid when our current parent became so */
 
 	u64 *prior_parent_snaps;      /* snaps inherited from any parents we had prior to parent_since */
-- 
2.47.3