---
Version 2:
- extend use of xfs_ifork_alloc() helper
- formalise "size == 0" behaviour of xfs_bmap_set_attrforkoff() to
mean "use default offset"
- use xfs_bmap_set_attrforkoff() from xfs_init_new_inode()
- add xfs_create_need_xattr() helper function to decide if we should
init the attr fork during create and document why we are peaking
at superblock security gubbins to make that decision.
fs/xfs/libxfs/xfs_bmap.c | 19 ++++++++++++++-----
fs/xfs/libxfs/xfs_inode_fork.c | 20 +++++++++++++++-----
fs/xfs/libxfs/xfs_inode_fork.h | 2 ++
fs/xfs/xfs_inode.c | 23 ++++++++++++++++++++---
fs/xfs/xfs_inode.h | 5 +++--
fs/xfs/xfs_iops.c | 35 ++++++++++++++++++++++++++++++++++-
fs/xfs/xfs_qm.c | 2 +-
fs/xfs/xfs_symlink.c | 2 +-
8 files changed, 90 insertions(+), 18 deletions(-)
diff --git a/fs/xfs/libxfs/xfs_bmap.c b/fs/xfs/libxfs/xfs_bmap.c
index e0905ad171f0..f7bcb0dfa15f 100644
--- a/fs/xfs/libxfs/xfs_bmap.c
+++ b/fs/xfs/libxfs/xfs_bmap.c
@@ -1027,7 +1027,14 @@ xfs_bmap_add_attrfork_local(
return -EFSCORRUPTED;
}
-/* Set an inode attr fork off based on the format */
+/*
+ * Set an inode attr fork offset based on the format of the data fork.
+ *
+ * If a size of zero is passed in, then caller does not know the size of
+ * the attribute that might be added (i.e. pre-emptive attr fork creation).
+ * Hence in this case just set the fork offset to the default so that we don't
+ * need to modify the supported attr format in the superblock.
+ */
int
xfs_bmap_set_attrforkoff(
struct xfs_inode *ip,
@@ -1041,6 +1048,11 @@ xfs_bmap_set_attrforkoff(
case XFS_DINODE_FMT_LOCAL:
case XFS_DINODE_FMT_EXTENTS:
case XFS_DINODE_FMT_BTREE:
+ if (size == 0) {
+ ASSERT(!version);
+ ip->i_d.di_forkoff = xfs_default_attroffset(ip) >> 3;
+ break;
+ }
ip->i_d.di_forkoff = xfs_attr_shortform_bytesfit(ip, size);
if (!ip->i_d.di_forkoff)
ip->i_d.di_forkoff = xfs_default_attroffset(ip) >> 3;
@@ -1092,10 +1104,7 @@ xfs_bmap_add_attrfork(
goto trans_cancel;
ASSERT(ip->i_afp == NULL);
- ip->i_afp = kmem_cache_zalloc(xfs_ifork_zone,
- GFP_KERNEL | __GFP_NOFAIL);
-
- ip->i_afp->if_format = XFS_DINODE_FMT_EXTENTS;
+ ip->i_afp = xfs_ifork_alloc(XFS_DINODE_FMT_EXTENTS, 0);
ip->i_afp->if_flags = XFS_IFEXTENTS;
logflags = 0;
switch (ip->i_df.if_format) {
diff --git a/fs/xfs/libxfs/xfs_inode_fork.c b/fs/xfs/libxfs/xfs_inode_fork.c
index e080d7e07643..c606c1a77e5a 100644
--- a/fs/xfs/libxfs/xfs_inode_fork.c
+++ b/fs/xfs/libxfs/xfs_inode_fork.c
@@ -282,6 +282,19 @@ xfs_dfork_attr_shortform_size(
return be16_to_cpu(atp->hdr.totsize);
}
+struct xfs_ifork *
+xfs_ifork_alloc(
+ enum xfs_dinode_fmt format,
+ xfs_extnum_t nextents)
+{
+ struct xfs_ifork *ifp;
+
+ ifp = kmem_cache_zalloc(xfs_ifork_zone, GFP_NOFS | __GFP_NOFAIL);
+ ifp->if_format = format;
+ ifp->if_nextents = nextents;
+ return ifp;
+}
+
int
xfs_iformat_attr_fork(
struct xfs_inode *ip,
@@ -293,11 +306,8 @@ xfs_iformat_attr_fork(
* Initialize the extent count early, as the per-format routines may
* depend on it.
*/
- ip->i_afp = kmem_cache_zalloc(xfs_ifork_zone, GFP_NOFS | __GFP_NOFAIL);
- ip->i_afp->if_format = dip->di_aformat;
- if (unlikely(ip->i_afp->if_format == 0)) /* pre IRIX 6.2 file system */
- ip->i_afp->if_format = XFS_DINODE_FMT_EXTENTS;
- ip->i_afp->if_nextents = be16_to_cpu(dip->di_anextents);
+ ip->i_afp = xfs_ifork_alloc(dip->di_aformat,
+ be16_to_cpu(dip->di_anextents));
switch (ip->i_afp->if_format) {
case XFS_DINODE_FMT_LOCAL:
diff --git a/fs/xfs/libxfs/xfs_inode_fork.h b/fs/xfs/libxfs/xfs_inode_fork.h
index 9e2137cd7372..a0717ab0e5c5 100644
--- a/fs/xfs/libxfs/xfs_inode_fork.h
+++ b/fs/xfs/libxfs/xfs_inode_fork.h
@@ -141,6 +141,8 @@ static inline int8_t xfs_ifork_format(struct xfs_ifork *ifp)
return ifp->if_format;
}
+struct xfs_ifork *xfs_ifork_alloc(enum xfs_dinode_fmt format,
+ xfs_extnum_t nextents);
struct xfs_ifork *xfs_iext_state_to_fork(struct xfs_inode *ip, int state);
int xfs_iformat_data_fork(struct xfs_inode *, struct xfs_dinode *);
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index 636ac13b1df2..95e3a5e6e5e2 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -773,6 +773,7 @@ xfs_init_new_inode(
xfs_nlink_t nlink,
dev_t rdev,
prid_t prid,
+ bool init_xattrs,
struct xfs_inode **ipp)
{
struct inode *dir = pip ? VFS_I(pip) : NULL;
@@ -875,6 +876,18 @@ xfs_init_new_inode(
ASSERT(0);
}
+ /*
+ * If we need to create attributes immediately after allocating the
+ * inode, initialise an empty attribute fork right now. We use the
+ * default fork offset for attributes here as we don't know exactly what
+ * size or how many attributes we might be adding. We can do this safely
+ * here because we know the data fork is completely empty right now.
+ */
+ if (init_xattrs) {
+ xfs_bmap_set_attrforkoff(ip, 0, NULL);
+ ip->i_afp = xfs_ifork_alloc(XFS_DINODE_FMT_EXTENTS, 0);
+ }
+
/*
* Log the new values stuffed into the inode.
*/
@@ -907,6 +920,7 @@ xfs_dir_ialloc(
xfs_nlink_t nlink,
dev_t rdev,
prid_t prid,
+ bool init_xattrs,
struct xfs_inode **ipp)
{
struct xfs_buf *agibp;
@@ -933,7 +947,8 @@ xfs_dir_ialloc(
return error;
ASSERT(ino != NULLFSINO);
- return xfs_init_new_inode(*tpp, dp, ino, mode, nlink, rdev, prid, ipp);
+ return xfs_init_new_inode(*tpp, dp, ino, mode, nlink, rdev, prid,
+ init_xattrs, ipp);
}
/*
@@ -977,6 +992,7 @@ xfs_create(
struct xfs_name *name,
umode_t mode,
dev_t rdev,
+ bool init_xattrs,
xfs_inode_t **ipp)
{
int is_dir = S_ISDIR(mode);
@@ -1046,7 +1062,8 @@ xfs_create(
* entry pointing to them, but a directory also the "." entry
* pointing to itself.
*/
- error = xfs_dir_ialloc(&tp, dp, mode, is_dir ? 2 : 1, rdev, prid, &ip);
+ error = xfs_dir_ialloc(&tp, dp, mode, is_dir ? 2 : 1, rdev, prid,
+ init_xattrs, &ip);
if (error)
goto out_trans_cancel;
@@ -1164,7 +1181,7 @@ xfs_create_tmpfile(
if (error)
goto out_release_dquots;
- error = xfs_dir_ialloc(&tp, dp, mode, 0, 0, prid, &ip);
+ error = xfs_dir_ialloc(&tp, dp, mode, 0, 0, prid, false, &ip);
if (error)
goto out_trans_cancel;
diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index eca333f5f715..4d3caff2a24a 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -370,7 +370,8 @@ void xfs_inactive(struct xfs_inode *ip);
int xfs_lookup(struct xfs_inode *dp, struct xfs_name *name,
struct xfs_inode **ipp, struct xfs_name *ci_name);
int xfs_create(struct xfs_inode *dp, struct xfs_name *name,
- umode_t mode, dev_t rdev, struct xfs_inode **ipp);
+ umode_t mode, dev_t rdev, bool need_xattr,
+ struct xfs_inode **ipp);
int xfs_create_tmpfile(struct xfs_inode *dp, umode_t mode,
struct xfs_inode **ipp);
int xfs_remove(struct xfs_inode *dp, struct xfs_name *name,
@@ -408,7 +409,7 @@ xfs_extlen_t xfs_get_extsz_hint(struct xfs_inode *ip);
xfs_extlen_t xfs_get_cowextsz_hint(struct xfs_inode *ip);
int xfs_dir_ialloc(struct xfs_trans **tpp, struct xfs_inode *dp, umode_t mode,
- xfs_nlink_t nlink, dev_t dev, prid_t prid,
+ xfs_nlink_t nlink, dev_t dev, prid_t prid, bool need_xattr,
struct xfs_inode **ipp);
static inline int
diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index 00369502fe25..5984760e8a64 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -126,6 +126,37 @@ xfs_cleanup_inode(
xfs_remove(XFS_I(dir), &teardown, XFS_I(inode));
}
+/*
+ * Check to see if we are likely to need an extended attribute to be added to
+ * the inode we are about to allocate. This allows the attribute fork to be
+ * created during the inode allocation, reducing the number of transactions we
+ * need to do in this fast path.
+ *
+ * The security checks are optimistic, but not guaranteed. The two LSMs that
+ * require xattrs to be added here (selinux and smack) are also the only two
+ * LSMs that add a sb->s_security structure to the superblock. Hence if security
+ * is enabled and sb->s_security is set, we have a pretty good idea that we are
+ * going to be asked to add a security xattr immediately after allocating the
+ * xfs inode and instantiating the VFS inode.
+ */
+static inline bool
+xfs_create_need_xattr(
+ struct inode *dir,
+ struct posix_acl *default_acl,
+ struct posix_acl *acl)
+{
+ if (acl)
+ return true;
+ if (default_acl)
+ return true;
+ if (!IS_ENABLED(CONFIG_SECURITY))
+ return false;
+ if (dir->i_sb->s_security)
+ return true;
+ return false;
+}
+
+
STATIC int
xfs_generic_create(
struct inode *dir,
@@ -161,7 +192,9 @@ xfs_generic_create(
goto out_free_acl;
if (!tmpfile) {
- error = xfs_create(XFS_I(dir), &name, mode, rdev, &ip);
+ error = xfs_create(XFS_I(dir), &name, mode, rdev,
+ xfs_create_need_xattr(dir, default_acl, acl),
+ &ip);
} else {
error = xfs_create_tmpfile(XFS_I(dir), mode, &ip);
}
diff --git a/fs/xfs/xfs_qm.c b/fs/xfs/xfs_qm.c
index 742d1413e2d0..262ea047cb4f 100644
--- a/fs/xfs/xfs_qm.c
+++ b/fs/xfs/xfs_qm.c
@@ -787,7 +787,7 @@ xfs_qm_qino_alloc(
return error;
if (need_alloc) {
- error = xfs_dir_ialloc(&tp, NULL, S_IFREG, 1, 0, 0, ipp);
+ error = xfs_dir_ialloc(&tp, NULL, S_IFREG, 1, 0, 0, false, ipp);
if (error) {
xfs_trans_cancel(tp);
return error;
diff --git a/fs/xfs/xfs_symlink.c b/fs/xfs/xfs_symlink.c
index 8565663b16cd..ab42f6e0d26e 100644
--- a/fs/xfs/xfs_symlink.c
+++ b/fs/xfs/xfs_symlink.c
@@ -222,7 +222,7 @@ xfs_symlink(
* Allocate an inode for the symlink.
*/
error = xfs_dir_ialloc(&tp, dp, S_IFLNK | (mode & ~S_IFMT), 1, 0,
- prid, &ip);
+ prid, false, &ip);
if (error)
goto out_trans_cancel;
