v4.19.13 snapshot.
diff --git a/fs/nfs/nfs3acl.c b/fs/nfs/nfs3acl.c
new file mode 100644
index 0000000..9fce185
--- /dev/null
+++ b/fs/nfs/nfs3acl.c
@@ -0,0 +1,338 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/fs.h>
+#include <linux/gfp.h>
+#include <linux/nfs.h>
+#include <linux/nfs3.h>
+#include <linux/nfs_fs.h>
+#include <linux/posix_acl_xattr.h>
+#include <linux/nfsacl.h>
+
+#include "internal.h"
+#include "nfs3_fs.h"
+
+#define NFSDBG_FACILITY NFSDBG_PROC
+
+/*
+ * nfs3_prepare_get_acl, nfs3_complete_get_acl, nfs3_abort_get_acl: Helpers for
+ * caching get_acl results in a race-free way. See fs/posix_acl.c:get_acl()
+ * for explanations.
+ */
+static void nfs3_prepare_get_acl(struct posix_acl **p)
+{
+ struct posix_acl *sentinel = uncached_acl_sentinel(current);
+
+ if (cmpxchg(p, ACL_NOT_CACHED, sentinel) != ACL_NOT_CACHED) {
+ /* Not the first reader or sentinel already in place. */
+ }
+}
+
+static void nfs3_complete_get_acl(struct posix_acl **p, struct posix_acl *acl)
+{
+ struct posix_acl *sentinel = uncached_acl_sentinel(current);
+
+ /* Only cache the ACL if our sentinel is still in place. */
+ posix_acl_dup(acl);
+ if (cmpxchg(p, sentinel, acl) != sentinel)
+ posix_acl_release(acl);
+}
+
+static void nfs3_abort_get_acl(struct posix_acl **p)
+{
+ struct posix_acl *sentinel = uncached_acl_sentinel(current);
+
+ /* Remove our sentinel upon failure. */
+ cmpxchg(p, sentinel, ACL_NOT_CACHED);
+}
+
+struct posix_acl *nfs3_get_acl(struct inode *inode, int type)
+{
+ struct nfs_server *server = NFS_SERVER(inode);
+ struct page *pages[NFSACL_MAXPAGES] = { };
+ struct nfs3_getaclargs args = {
+ .fh = NFS_FH(inode),
+ /* The xdr layer may allocate pages here. */
+ .pages = pages,
+ };
+ struct nfs3_getaclres res = {
+ NULL,
+ };
+ struct rpc_message msg = {
+ .rpc_argp = &args,
+ .rpc_resp = &res,
+ };
+ int status, count;
+
+ if (!nfs_server_capable(inode, NFS_CAP_ACLS))
+ return ERR_PTR(-EOPNOTSUPP);
+
+ status = nfs_revalidate_inode(server, inode);
+ if (status < 0)
+ return ERR_PTR(status);
+
+ /*
+ * Only get the access acl when explicitly requested: We don't
+ * need it for access decisions, and only some applications use
+ * it. Applications which request the access acl first are not
+ * penalized from this optimization.
+ */
+ if (type == ACL_TYPE_ACCESS)
+ args.mask |= NFS_ACLCNT|NFS_ACL;
+ if (S_ISDIR(inode->i_mode))
+ args.mask |= NFS_DFACLCNT|NFS_DFACL;
+ if (args.mask == 0)
+ return NULL;
+
+ dprintk("NFS call getacl\n");
+ msg.rpc_proc = &server->client_acl->cl_procinfo[ACLPROC3_GETACL];
+ res.fattr = nfs_alloc_fattr();
+ if (res.fattr == NULL)
+ return ERR_PTR(-ENOMEM);
+
+ if (args.mask & NFS_ACL)
+ nfs3_prepare_get_acl(&inode->i_acl);
+ if (args.mask & NFS_DFACL)
+ nfs3_prepare_get_acl(&inode->i_default_acl);
+
+ status = rpc_call_sync(server->client_acl, &msg, 0);
+ dprintk("NFS reply getacl: %d\n", status);
+
+ /* pages may have been allocated at the xdr layer. */
+ for (count = 0; count < NFSACL_MAXPAGES && args.pages[count]; count++)
+ __free_page(args.pages[count]);
+
+ switch (status) {
+ case 0:
+ status = nfs_refresh_inode(inode, res.fattr);
+ break;
+ case -EPFNOSUPPORT:
+ case -EPROTONOSUPPORT:
+ dprintk("NFS_V3_ACL extension not supported; disabling\n");
+ server->caps &= ~NFS_CAP_ACLS;
+ /* fall through */
+ case -ENOTSUPP:
+ status = -EOPNOTSUPP;
+ default:
+ goto getout;
+ }
+ if ((args.mask & res.mask) != args.mask) {
+ status = -EIO;
+ goto getout;
+ }
+
+ if (res.acl_access != NULL) {
+ if ((posix_acl_equiv_mode(res.acl_access, NULL) == 0) ||
+ res.acl_access->a_count == 0) {
+ posix_acl_release(res.acl_access);
+ res.acl_access = NULL;
+ }
+ }
+
+ if (res.mask & NFS_ACL)
+ nfs3_complete_get_acl(&inode->i_acl, res.acl_access);
+ else
+ forget_cached_acl(inode, ACL_TYPE_ACCESS);
+
+ if (res.mask & NFS_DFACL)
+ nfs3_complete_get_acl(&inode->i_default_acl, res.acl_default);
+ else
+ forget_cached_acl(inode, ACL_TYPE_DEFAULT);
+
+ nfs_free_fattr(res.fattr);
+ if (type == ACL_TYPE_ACCESS) {
+ posix_acl_release(res.acl_default);
+ return res.acl_access;
+ } else {
+ posix_acl_release(res.acl_access);
+ return res.acl_default;
+ }
+
+getout:
+ nfs3_abort_get_acl(&inode->i_acl);
+ nfs3_abort_get_acl(&inode->i_default_acl);
+ posix_acl_release(res.acl_access);
+ posix_acl_release(res.acl_default);
+ nfs_free_fattr(res.fattr);
+ return ERR_PTR(status);
+}
+
+static int __nfs3_proc_setacls(struct inode *inode, struct posix_acl *acl,
+ struct posix_acl *dfacl)
+{
+ struct nfs_server *server = NFS_SERVER(inode);
+ struct nfs_fattr *fattr;
+ struct page *pages[NFSACL_MAXPAGES];
+ struct nfs3_setaclargs args = {
+ .inode = inode,
+ .mask = NFS_ACL,
+ .acl_access = acl,
+ .pages = pages,
+ };
+ struct rpc_message msg = {
+ .rpc_argp = &args,
+ .rpc_resp = &fattr,
+ };
+ int status = 0;
+
+ if (acl == NULL && (!S_ISDIR(inode->i_mode) || dfacl == NULL))
+ goto out;
+
+ status = -EOPNOTSUPP;
+ if (!nfs_server_capable(inode, NFS_CAP_ACLS))
+ goto out;
+
+ /* We are doing this here because XDR marshalling does not
+ * return any results, it BUGs. */
+ status = -ENOSPC;
+ if (acl != NULL && acl->a_count > NFS_ACL_MAX_ENTRIES)
+ goto out;
+ if (dfacl != NULL && dfacl->a_count > NFS_ACL_MAX_ENTRIES)
+ goto out;
+ if (S_ISDIR(inode->i_mode)) {
+ args.mask |= NFS_DFACL;
+ args.acl_default = dfacl;
+ args.len = nfsacl_size(acl, dfacl);
+ } else
+ args.len = nfsacl_size(acl, NULL);
+
+ if (args.len > NFS_ACL_INLINE_BUFSIZE) {
+ unsigned int npages = 1 + ((args.len - 1) >> PAGE_SHIFT);
+
+ status = -ENOMEM;
+ do {
+ args.pages[args.npages] = alloc_page(GFP_KERNEL);
+ if (args.pages[args.npages] == NULL)
+ goto out_freepages;
+ args.npages++;
+ } while (args.npages < npages);
+ }
+
+ dprintk("NFS call setacl\n");
+ status = -ENOMEM;
+ fattr = nfs_alloc_fattr();
+ if (fattr == NULL)
+ goto out_freepages;
+
+ msg.rpc_proc = &server->client_acl->cl_procinfo[ACLPROC3_SETACL];
+ msg.rpc_resp = fattr;
+ status = rpc_call_sync(server->client_acl, &msg, 0);
+ nfs_access_zap_cache(inode);
+ nfs_zap_acl_cache(inode);
+ dprintk("NFS reply setacl: %d\n", status);
+
+ switch (status) {
+ case 0:
+ status = nfs_refresh_inode(inode, fattr);
+ set_cached_acl(inode, ACL_TYPE_ACCESS, acl);
+ set_cached_acl(inode, ACL_TYPE_DEFAULT, dfacl);
+ break;
+ case -EPFNOSUPPORT:
+ case -EPROTONOSUPPORT:
+ dprintk("NFS_V3_ACL SETACL RPC not supported"
+ "(will not retry)\n");
+ server->caps &= ~NFS_CAP_ACLS;
+ /* fall through */
+ case -ENOTSUPP:
+ status = -EOPNOTSUPP;
+ }
+ nfs_free_fattr(fattr);
+out_freepages:
+ while (args.npages != 0) {
+ args.npages--;
+ __free_page(args.pages[args.npages]);
+ }
+out:
+ return status;
+}
+
+int nfs3_proc_setacls(struct inode *inode, struct posix_acl *acl,
+ struct posix_acl *dfacl)
+{
+ int ret;
+ ret = __nfs3_proc_setacls(inode, acl, dfacl);
+ return (ret == -EOPNOTSUPP) ? 0 : ret;
+
+}
+
+int nfs3_set_acl(struct inode *inode, struct posix_acl *acl, int type)
+{
+ struct posix_acl *alloc = NULL, *dfacl = NULL;
+ int status;
+
+ if (S_ISDIR(inode->i_mode)) {
+ switch(type) {
+ case ACL_TYPE_ACCESS:
+ alloc = dfacl = get_acl(inode, ACL_TYPE_DEFAULT);
+ if (IS_ERR(alloc))
+ goto fail;
+ break;
+
+ case ACL_TYPE_DEFAULT:
+ dfacl = acl;
+ alloc = acl = get_acl(inode, ACL_TYPE_ACCESS);
+ if (IS_ERR(alloc))
+ goto fail;
+ break;
+ }
+ }
+
+ if (acl == NULL) {
+ alloc = acl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL);
+ if (IS_ERR(alloc))
+ goto fail;
+ }
+ status = __nfs3_proc_setacls(inode, acl, dfacl);
+ posix_acl_release(alloc);
+ return status;
+
+fail:
+ return PTR_ERR(alloc);
+}
+
+const struct xattr_handler *nfs3_xattr_handlers[] = {
+ &posix_acl_access_xattr_handler,
+ &posix_acl_default_xattr_handler,
+ NULL,
+};
+
+static int
+nfs3_list_one_acl(struct inode *inode, int type, const char *name, void *data,
+ size_t size, ssize_t *result)
+{
+ struct posix_acl *acl;
+ char *p = data + *result;
+
+ acl = get_acl(inode, type);
+ if (IS_ERR_OR_NULL(acl))
+ return 0;
+
+ posix_acl_release(acl);
+
+ *result += strlen(name);
+ *result += 1;
+ if (!size)
+ return 0;
+ if (*result > size)
+ return -ERANGE;
+
+ strcpy(p, name);
+ return 0;
+}
+
+ssize_t
+nfs3_listxattr(struct dentry *dentry, char *data, size_t size)
+{
+ struct inode *inode = d_inode(dentry);
+ ssize_t result = 0;
+ int error;
+
+ error = nfs3_list_one_acl(inode, ACL_TYPE_ACCESS,
+ XATTR_NAME_POSIX_ACL_ACCESS, data, size, &result);
+ if (error)
+ return error;
+
+ error = nfs3_list_one_acl(inode, ACL_TYPE_DEFAULT,
+ XATTR_NAME_POSIX_ACL_DEFAULT, data, size, &result);
+ if (error)
+ return error;
+ return result;
+}