From 5febf432df1cfa5b25d99b54c32103fafbdd0eb9 Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Sun, 16 Aug 2026 15:32:33 +0200 Subject: kbuild: rust: keep Rust objects out of Clang LTO with inline helpers Under `CONFIG_LTO_CLANG` + `CONFIG_RUST_INLINE_HELPERS`, one may hit `objtool` errors such as: vmlinux.o: error: objtool: _R..._3Gsp4boot+0xd6a: can't find jump dest instruction at .text._R..._3Gsp4boot+0x1dfd The reason is that in such builds, the Clang invocation that compiles the combined Rust plus helpers bitcode emits LLVM bitcode (again) -- the final code generation happens in the linker's LTO step, which the `-mllvm` trap options passed to Clang do not reach. This, in turn, means that unreachable traps are missing, and the impossible paths do not merely fallthrough to the next symbol, but past the end of their own section, since LTO builds place each function in its own section. Thus filter `CC_FLAGS_LTO` out of the Clang invocation, so that it always emits machine code directly, with the traps in place. Assisted-by: LLM Cc: Gary Guo Cc: Boqun Feng Cc: Alice Ryhl Cc: Matthew Maurer Cc: Josh Poimboeuf Cc: Peter Zijlstra Cc: stable@vger.kernel.org Fixes: 3a2486cc1da5 ("kbuild: rust: provide an option to inline C helpers into Rust") Acked-by: Gary Guo Link: https://patch.msgid.link/20260816133233.197500-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda --- fs/nfsd/flexfilelayout.c | 144 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 144 insertions(+) create mode 100644 fs/nfsd/flexfilelayout.c (limited to 'fs/nfsd/flexfilelayout.c') diff --git a/fs/nfsd/flexfilelayout.c b/fs/nfsd/flexfilelayout.c new file mode 100644 index 000000000..6d531285a --- /dev/null +++ b/fs/nfsd/flexfilelayout.c @@ -0,0 +1,144 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2016 Tom Haynes + * + * The following implements a super-simple flex-file server + * where the NFSv4.1 mds is also the ds. And the storage is + * the same. I.e., writing to the mds via a NFSv4.1 WRITE + * goes to the same location as the NFSv3 WRITE. + */ +#include + +#include + +#include + +#include "flexfilelayoutxdr.h" +#include "pnfs.h" +#include "vfs.h" + +#define NFSDDBG_FACILITY NFSDDBG_PNFS + +static __be32 +nfsd4_ff_proc_layoutget(struct svc_rqst *rqstp, struct inode *inode, + const struct svc_fh *fhp, struct nfsd4_layoutget *args) +{ + struct nfsd4_layout_seg *seg = &args->lg_seg; + u32 device_generation = 0; + int error; + uid_t u; + + struct pnfs_ff_layout *fl; + + /* + * The super simple flex file server has 1 mirror, 1 data server, + * and 1 file handle. So instead of 4 allocs, do 1 for now. + * Zero it out for the stateid - don't want junk in there! + */ + error = -ENOMEM; + fl = kzalloc_obj(*fl); + if (!fl) + goto out_error; + args->lg_content = fl; + + /* + * Avoid layout commit, try to force the I/O to the DS, + * and for fun, cause all IOMODE_RW layout segments to + * effectively be WRITE only. + */ + fl->flags = FF_FLAGS_NO_LAYOUTCOMMIT | FF_FLAGS_NO_IO_THRU_MDS | + FF_FLAGS_NO_READ_IO; + + /* Do not allow a IOMODE_READ segment to have write pemissions */ + if (seg->iomode == IOMODE_READ) { + u = from_kuid(&init_user_ns, inode->i_uid) + 1; + fl->uid = make_kuid(&init_user_ns, u); + } else + fl->uid = inode->i_uid; + fl->gid = inode->i_gid; + + error = nfsd4_set_deviceid(&fl->deviceid, fhp, device_generation); + if (error) + goto out_error; + + fl->fh.size = fhp->fh_handle.fh_size; + memcpy(fl->fh.data, &fhp->fh_handle.fh_raw, fl->fh.size); + + /* Give whole file layout segments */ + seg->offset = 0; + seg->length = NFS4_MAX_UINT64; + + dprintk("GET: 0x%llx:0x%llx %d\n", seg->offset, seg->length, + seg->iomode); + return 0; + +out_error: + seg->length = 0; + return nfserrno(error); +} + +static __be32 +nfsd4_ff_proc_getdeviceinfo(struct super_block *sb, struct svc_rqst *rqstp, + struct nfs4_client *clp, struct nfsd4_getdeviceinfo *gdp) +{ + struct pnfs_ff_device_addr *da; + + u16 port; + char addr[INET6_ADDRSTRLEN]; + + da = kzalloc_obj(struct pnfs_ff_device_addr); + if (!da) + return nfserrno(-ENOMEM); + + gdp->gd_device = da; + + da->version = 3; + da->minor_version = 0; + + da->rsize = svc_max_payload(rqstp); + da->wsize = da->rsize; + + rpc_ntop((struct sockaddr *)&rqstp->rq_daddr, + addr, INET6_ADDRSTRLEN); + if (rqstp->rq_daddr.ss_family == AF_INET) { + struct sockaddr_in *sin; + + sin = (struct sockaddr_in *)&rqstp->rq_daddr; + port = ntohs(sin->sin_port); + snprintf(da->netaddr.netid, FF_NETID_LEN + 1, "tcp"); + da->netaddr.netid_len = 3; + } else { + struct sockaddr_in6 *sin6; + + sin6 = (struct sockaddr_in6 *)&rqstp->rq_daddr; + port = ntohs(sin6->sin6_port); + snprintf(da->netaddr.netid, FF_NETID_LEN + 1, "tcp6"); + da->netaddr.netid_len = 4; + } + + da->netaddr.addr_len = + snprintf(da->netaddr.addr, FF_ADDR_LEN + 1, + "%s.%d.%d", addr, port >> 8, port & 0xff); + + da->tightly_coupled = false; + + return 0; +} + +static __be32 +nfsd4_ff_proc_layoutcommit(struct inode *inode, struct svc_rqst *rqstp, + struct nfsd4_layoutcommit *lcp) +{ + return nfs_ok; +} + +const struct nfsd4_layout_ops ff_layout_ops = { + .notify_types = + NOTIFY_DEVICEID4_DELETE | NOTIFY_DEVICEID4_CHANGE, + .disable_recalls = true, + .proc_getdeviceinfo = nfsd4_ff_proc_getdeviceinfo, + .encode_getdeviceinfo = nfsd4_ff_encode_getdeviceinfo, + .proc_layoutget = nfsd4_ff_proc_layoutget, + .encode_layoutget = nfsd4_ff_encode_layoutget, + .proc_layoutcommit = nfsd4_ff_proc_layoutcommit, +}; -- cgit v1.3.1