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/xfs/scrub/rtbitmap.c | 299 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 299 insertions(+) create mode 100644 fs/xfs/scrub/rtbitmap.c (limited to 'fs/xfs/scrub/rtbitmap.c') diff --git a/fs/xfs/scrub/rtbitmap.c b/fs/xfs/scrub/rtbitmap.c new file mode 100644 index 000000000..52c24d3d4 --- /dev/null +++ b/fs/xfs/scrub/rtbitmap.c @@ -0,0 +1,299 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2017-2023 Oracle. All Rights Reserved. + * Author: Darrick J. Wong + */ +#include "xfs_platform.h" +#include "xfs_fs.h" +#include "xfs_shared.h" +#include "xfs_format.h" +#include "xfs_trans_resv.h" +#include "xfs_mount.h" +#include "xfs_btree.h" +#include "xfs_log_format.h" +#include "xfs_trans.h" +#include "xfs_rtbitmap.h" +#include "xfs_inode.h" +#include "xfs_bmap.h" +#include "xfs_bit.h" +#include "xfs_rtgroup.h" +#include "xfs_sb.h" +#include "xfs_rmap.h" +#include "xfs_rtrmap_btree.h" +#include "xfs_exchmaps.h" +#include "xfs_zone_alloc.h" +#include "scrub/scrub.h" +#include "scrub/common.h" +#include "scrub/repair.h" +#include "scrub/tempexch.h" +#include "scrub/rtbitmap.h" +#include "scrub/btree.h" + +/* Set us up with the realtime metadata locked. */ +int +xchk_setup_rtbitmap( + struct xfs_scrub *sc) +{ + struct xfs_mount *mp = sc->mp; + struct xchk_rtbitmap *rtb; + int error; + + if (xchk_need_intent_drain(sc)) + xchk_fsgates_enable(sc, XCHK_FSGATES_DRAIN); + + rtb = kzalloc_flex(*rtb, words, xchk_rtbitmap_wordcnt(sc), + XCHK_GFP_FLAGS); + if (!rtb) + return -ENOMEM; + sc->buf = rtb; + rtb->sc = sc; + + error = xchk_rtgroup_init(sc, sc->sm->sm_agno, &sc->sr); + if (error) + return error; + + if (xchk_could_repair(sc)) { + error = xrep_setup_rtbitmap(sc, rtb); + if (error) + return error; + } + + error = xchk_trans_alloc(sc, rtb->resblks); + if (error) + return error; + + error = xchk_install_live_inode(sc, rtg_bitmap(sc->sr.rtg)); + if (error) + return error; + + error = xchk_ino_dqattach(sc); + if (error) + return error; + + error = xchk_rtgroup_lock(sc, &sc->sr, XCHK_RTGLOCK_ALL); + if (error) + return error; + + /* + * Now that we've locked the rtbitmap, we can't race with growfsrt + * trying to expand the bitmap or change the size of the rt volume. + * Hence it is safe to compute and check the geometry values. + */ + if (mp->m_sb.sb_rblocks) { + rtb->rextents = xfs_blen_to_rtbxlen(mp, mp->m_sb.sb_rblocks); + rtb->rextslog = xfs_compute_rextslog(rtb->rextents); + rtb->rbmblocks = xfs_rtbitmap_blockcount(mp); + } + + return 0; +} + +/* Per-rtgroup bitmap contents. */ + +/* Cross-reference rtbitmap entries with other metadata. */ +STATIC void +xchk_rtbitmap_xref( + struct xchk_rtbitmap *rtb, + xfs_rtblock_t startblock, + xfs_rtblock_t blockcount) +{ + struct xfs_scrub *sc = rtb->sc; + xfs_rgblock_t rgbno = xfs_rtb_to_rgbno(sc->mp, startblock); + + if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT) + return; + if (!sc->sr.rmap_cur) + return; + + xchk_xref_has_no_rt_owner(sc, rgbno, blockcount); + xchk_xref_is_not_rt_shared(sc, rgbno, blockcount); + xchk_xref_is_not_rt_cow_staging(sc, rgbno, blockcount); + + if (rtb->next_free_rgbno < rgbno) + xchk_xref_has_rt_owner(sc, rtb->next_free_rgbno, + rgbno - rtb->next_free_rgbno); + rtb->next_free_rgbno = rgbno + blockcount; +} + +/* Scrub a free extent record from the realtime bitmap. */ +STATIC int +xchk_rtbitmap_rec( + struct xfs_rtgroup *rtg, + struct xfs_trans *tp, + const struct xfs_rtalloc_rec *rec, + void *priv) +{ + struct xchk_rtbitmap *rtb = priv; + struct xfs_scrub *sc = rtb->sc; + xfs_rtblock_t startblock; + xfs_filblks_t blockcount; + + startblock = xfs_rtx_to_rtb(rtg, rec->ar_startext); + blockcount = xfs_rtxlen_to_extlen(rtg_mount(rtg), rec->ar_extcount); + + if (!xfs_verify_rtbext(rtg_mount(rtg), startblock, blockcount)) + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, 0); + + xchk_rtbitmap_xref(rtb, startblock, blockcount); + + if (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT) + return -ECANCELED; + + return 0; +} + +/* Make sure the entire rtbitmap file is mapped with written extents. */ +STATIC int +xchk_rtbitmap_check_extents( + struct xfs_scrub *sc) +{ + struct xfs_bmbt_irec map; + struct xfs_iext_cursor icur; + struct xfs_mount *mp = sc->mp; + struct xfs_inode *ip = sc->ip; + xfs_fileoff_t off = 0; + xfs_fileoff_t endoff; + int error = 0; + + /* Mappings may not cross or lie beyond EOF. */ + endoff = XFS_B_TO_FSB(mp, ip->i_disk_size); + if (xfs_iext_lookup_extent(ip, &ip->i_df, endoff, &icur, &map)) { + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, endoff); + return 0; + } + + while (off < endoff) { + int nmap = 1; + + if (xchk_should_terminate(sc, &error) || + (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)) + break; + + /* Make sure we have a written extent. */ + error = xfs_bmapi_read(ip, off, endoff - off, &map, &nmap, + XFS_DATA_FORK); + if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, off, &error)) + break; + + if (nmap != 1 || !xfs_bmap_is_written_extent(&map)) { + xchk_fblock_set_corrupt(sc, XFS_DATA_FORK, off); + break; + } + + off += map.br_blockcount; + } + + return error; +} + +/* Scrub this group's realtime bitmap. */ +int +xchk_rtbitmap( + struct xfs_scrub *sc) +{ + struct xfs_mount *mp = sc->mp; + struct xfs_rtgroup *rtg = sc->sr.rtg; + struct xfs_inode *rbmip = rtg_bitmap(rtg); + struct xchk_rtbitmap *rtb = sc->buf; + xfs_rgblock_t last_rgbno; + int error; + + /* Is sb_rextents correct? */ + if (mp->m_sb.sb_rextents != rtb->rextents) { + xchk_ip_set_corrupt(sc, rbmip); + return 0; + } + + /* Is sb_rextslog correct? */ + if (mp->m_sb.sb_rextslog != rtb->rextslog) { + xchk_ip_set_corrupt(sc, rbmip); + return 0; + } + + /* + * Is sb_rbmblocks large enough to handle the current rt volume? In no + * case can we exceed 4bn bitmap blocks since the super field is a u32. + */ + if (rtb->rbmblocks > U32_MAX) { + xchk_ip_set_corrupt(sc, rbmip); + return 0; + } + if (mp->m_sb.sb_rbmblocks != rtb->rbmblocks) { + xchk_ip_set_corrupt(sc, rbmip); + return 0; + } + + /* The bitmap file length must be aligned to an fsblock. */ + if (rbmip->i_disk_size & mp->m_blockmask) { + xchk_ip_set_corrupt(sc, rbmip); + return 0; + } + + /* + * Is the bitmap file itself large enough to handle the rt volume? + * growfsrt expands the bitmap file before updating sb_rextents, so the + * file can be larger than sb_rbmblocks. + */ + if (rbmip->i_disk_size < XFS_FSB_TO_B(mp, rtb->rbmblocks)) { + xchk_ip_set_corrupt(sc, rbmip); + return 0; + } + + /* Invoke the fork scrubber. */ + error = xchk_metadata_inode_forks(sc); + if (error || (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)) + return error; + + error = xchk_rtbitmap_check_extents(sc); + if (error || (sc->sm->sm_flags & XFS_SCRUB_OFLAG_CORRUPT)) + return error; + + rtb->next_free_rgbno = 0; + error = xfs_rtalloc_query_all(rtg, sc->tp, xchk_rtbitmap_rec, rtb); + if (!xchk_fblock_process_error(sc, XFS_DATA_FORK, 0, &error)) + return error; + + /* + * Check that the are rmappings for all rt extents between the end of + * the last free extent we saw and the last possible extent in the rt + * group. + */ + last_rgbno = rtg->rtg_extents * mp->m_sb.sb_rextsize; + if (rtb->next_free_rgbno < last_rgbno) + xchk_xref_has_rt_owner(sc, rtb->next_free_rgbno, + last_rgbno - rtb->next_free_rgbno); + return 0; +} + +/* xref check that the extent is not free in the rtbitmap */ +void +xchk_xref_is_used_rt_space( + struct xfs_scrub *sc, + xfs_rtblock_t rtbno, + xfs_extlen_t len) +{ + struct xfs_rtgroup *rtg = sc->sr.rtg; + xfs_rtxnum_t startext; + xfs_rtxnum_t endext; + bool is_free; + int error; + + if (xchk_skip_xref(sc->sm)) + return; + + if (xfs_has_zoned(sc->mp)) { + if (!xfs_zone_rgbno_is_valid(rtg, + xfs_rtb_to_rgbno(sc->mp, rtbno) + len - 1)) + xchk_ip_xref_set_corrupt(sc, rtg_rmap(rtg)); + return; + } + + startext = xfs_rtb_to_rtx(sc->mp, rtbno); + endext = xfs_rtb_to_rtx(sc->mp, rtbno + len - 1); + error = xfs_rtalloc_extent_is_free(rtg, sc->tp, startext, + endext - startext + 1, &is_free); + if (!xchk_should_check_xref(sc, &error, NULL)) + return; + if (is_free) + xchk_ip_xref_set_corrupt(sc, rtg_bitmap(rtg)); +} -- cgit v1.3.1