v4.19.13 snapshot.
diff --git a/fs/xfs/xfs_xattr.c b/fs/xfs/xfs_xattr.c
new file mode 100644
index 0000000..63ee1d5
--- /dev/null
+++ b/fs/xfs/xfs_xattr.c
@@ -0,0 +1,239 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2008 Christoph Hellwig.
+ * Portions Copyright (C) 2000-2008 Silicon Graphics, Inc.
+ */
+
+#include "xfs.h"
+#include "xfs_format.h"
+#include "xfs_log_format.h"
+#include "xfs_trans_resv.h"
+#include "xfs_mount.h"
+#include "xfs_da_format.h"
+#include "xfs_inode.h"
+#include "xfs_attr.h"
+#include "xfs_attr_leaf.h"
+#include "xfs_acl.h"
+
+#include <linux/posix_acl_xattr.h>
+#include <linux/xattr.h>
+
+
+static int
+xfs_xattr_get(const struct xattr_handler *handler, struct dentry *unused,
+ struct inode *inode, const char *name, void *value, size_t size)
+{
+ int xflags = handler->flags;
+ struct xfs_inode *ip = XFS_I(inode);
+ int error, asize = size;
+
+ /* Convert Linux syscall to XFS internal ATTR flags */
+ if (!size) {
+ xflags |= ATTR_KERNOVAL;
+ value = NULL;
+ }
+
+ error = xfs_attr_get(ip, (unsigned char *)name, value, &asize, xflags);
+ if (error)
+ return error;
+ return asize;
+}
+
+void
+xfs_forget_acl(
+ struct inode *inode,
+ const char *name,
+ int xflags)
+{
+ /*
+ * Invalidate any cached ACLs if the user has bypassed the ACL
+ * interface. We don't validate the content whatsoever so it is caller
+ * responsibility to provide data in valid format and ensure i_mode is
+ * consistent.
+ */
+ if (xflags & ATTR_ROOT) {
+#ifdef CONFIG_XFS_POSIX_ACL
+ if (!strcmp(name, SGI_ACL_FILE))
+ forget_cached_acl(inode, ACL_TYPE_ACCESS);
+ else if (!strcmp(name, SGI_ACL_DEFAULT))
+ forget_cached_acl(inode, ACL_TYPE_DEFAULT);
+#endif
+ }
+}
+
+static int
+xfs_xattr_set(const struct xattr_handler *handler, struct dentry *unused,
+ struct inode *inode, const char *name, const void *value,
+ size_t size, int flags)
+{
+ int xflags = handler->flags;
+ struct xfs_inode *ip = XFS_I(inode);
+ int error;
+
+ /* Convert Linux syscall to XFS internal ATTR flags */
+ if (flags & XATTR_CREATE)
+ xflags |= ATTR_CREATE;
+ if (flags & XATTR_REPLACE)
+ xflags |= ATTR_REPLACE;
+
+ if (!value)
+ return xfs_attr_remove(ip, (unsigned char *)name, xflags);
+ error = xfs_attr_set(ip, (unsigned char *)name,
+ (void *)value, size, xflags);
+ if (!error)
+ xfs_forget_acl(inode, name, xflags);
+
+ return error;
+}
+
+static const struct xattr_handler xfs_xattr_user_handler = {
+ .prefix = XATTR_USER_PREFIX,
+ .flags = 0, /* no flags implies user namespace */
+ .get = xfs_xattr_get,
+ .set = xfs_xattr_set,
+};
+
+static const struct xattr_handler xfs_xattr_trusted_handler = {
+ .prefix = XATTR_TRUSTED_PREFIX,
+ .flags = ATTR_ROOT,
+ .get = xfs_xattr_get,
+ .set = xfs_xattr_set,
+};
+
+static const struct xattr_handler xfs_xattr_security_handler = {
+ .prefix = XATTR_SECURITY_PREFIX,
+ .flags = ATTR_SECURE,
+ .get = xfs_xattr_get,
+ .set = xfs_xattr_set,
+};
+
+const struct xattr_handler *xfs_xattr_handlers[] = {
+ &xfs_xattr_user_handler,
+ &xfs_xattr_trusted_handler,
+ &xfs_xattr_security_handler,
+#ifdef CONFIG_XFS_POSIX_ACL
+ &posix_acl_access_xattr_handler,
+ &posix_acl_default_xattr_handler,
+#endif
+ NULL
+};
+
+static void
+__xfs_xattr_put_listent(
+ struct xfs_attr_list_context *context,
+ char *prefix,
+ int prefix_len,
+ unsigned char *name,
+ int namelen)
+{
+ char *offset;
+ int arraytop;
+
+ if (!context->alist)
+ goto compute_size;
+
+ arraytop = context->count + prefix_len + namelen + 1;
+ if (arraytop > context->firstu) {
+ context->count = -1; /* insufficient space */
+ context->seen_enough = 1;
+ return;
+ }
+ offset = (char *)context->alist + context->count;
+ strncpy(offset, prefix, prefix_len);
+ offset += prefix_len;
+ strncpy(offset, (char *)name, namelen); /* real name */
+ offset += namelen;
+ *offset = '\0';
+
+compute_size:
+ context->count += prefix_len + namelen + 1;
+ return;
+}
+
+static void
+xfs_xattr_put_listent(
+ struct xfs_attr_list_context *context,
+ int flags,
+ unsigned char *name,
+ int namelen,
+ int valuelen)
+{
+ char *prefix;
+ int prefix_len;
+
+ ASSERT(context->count >= 0);
+
+ if (flags & XFS_ATTR_ROOT) {
+#ifdef CONFIG_XFS_POSIX_ACL
+ if (namelen == SGI_ACL_FILE_SIZE &&
+ strncmp(name, SGI_ACL_FILE,
+ SGI_ACL_FILE_SIZE) == 0) {
+ __xfs_xattr_put_listent(
+ context, XATTR_SYSTEM_PREFIX,
+ XATTR_SYSTEM_PREFIX_LEN,
+ XATTR_POSIX_ACL_ACCESS,
+ strlen(XATTR_POSIX_ACL_ACCESS));
+ } else if (namelen == SGI_ACL_DEFAULT_SIZE &&
+ strncmp(name, SGI_ACL_DEFAULT,
+ SGI_ACL_DEFAULT_SIZE) == 0) {
+ __xfs_xattr_put_listent(
+ context, XATTR_SYSTEM_PREFIX,
+ XATTR_SYSTEM_PREFIX_LEN,
+ XATTR_POSIX_ACL_DEFAULT,
+ strlen(XATTR_POSIX_ACL_DEFAULT));
+ }
+#endif
+
+ /*
+ * Only show root namespace entries if we are actually allowed to
+ * see them.
+ */
+ if (!capable(CAP_SYS_ADMIN))
+ return;
+
+ prefix = XATTR_TRUSTED_PREFIX;
+ prefix_len = XATTR_TRUSTED_PREFIX_LEN;
+ } else if (flags & XFS_ATTR_SECURE) {
+ prefix = XATTR_SECURITY_PREFIX;
+ prefix_len = XATTR_SECURITY_PREFIX_LEN;
+ } else {
+ prefix = XATTR_USER_PREFIX;
+ prefix_len = XATTR_USER_PREFIX_LEN;
+ }
+
+ __xfs_xattr_put_listent(context, prefix, prefix_len, name,
+ namelen);
+ return;
+}
+
+ssize_t
+xfs_vn_listxattr(
+ struct dentry *dentry,
+ char *data,
+ size_t size)
+{
+ struct xfs_attr_list_context context;
+ struct attrlist_cursor_kern cursor = { 0 };
+ struct inode *inode = d_inode(dentry);
+ int error;
+
+ /*
+ * First read the regular on-disk attributes.
+ */
+ memset(&context, 0, sizeof(context));
+ context.dp = XFS_I(inode);
+ context.cursor = &cursor;
+ context.resynch = 1;
+ context.alist = size ? data : NULL;
+ context.bufsize = size;
+ context.firstu = context.bufsize;
+ context.put_listent = xfs_xattr_put_listent;
+
+ error = xfs_attr_list_int(&context);
+ if (error)
+ return error;
+ if (context.count < 0)
+ return -ERANGE;
+
+ return context.count;
+}