git: 9e366ef5c8c7 - stable/13 - LinuxKPI: 802.11: adjust locking
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Date: Mon, 26 Jun 2023 12:08:38 UTC
The branch stable/13 has been updated by bz: URL: https://cgit.FreeBSD.org/src/commit/?id=9e366ef5c8c70e51c6826b3462bb3eea448c1009 commit 9e366ef5c8c70e51c6826b3462bb3eea448c1009 Author: Bjoern A. Zeeb <bz@FreeBSD.org> AuthorDate: 2023-03-31 19:52:19 +0000 Commit: Bjoern A. Zeeb <bz@FreeBSD.org> CommitDate: 2023-06-26 09:13:26 +0000 LinuxKPI: 802.11: adjust locking Split up the lhw lock and the scan lock. The latter is a mtx while the former changes from mtx to sx as mac80211 downcalls may sleep (and the ic lock is not usable in that case either and a larger project to fix). This will also enforce some lookups under lock (mostly scan) as well as general protection for more compat code and avoid a possible deadlock with one of the upcoming callbacks from driver into the compat code. Sponsored by: The FreeBSD Foundation (cherry picked from commit 8ac540d3b8bf9746216c4687b4629296357cf146) --- sys/compat/linuxkpi/common/src/linux_80211.c | 92 +++++++++++++++++++++++----- sys/compat/linuxkpi/common/src/linux_80211.h | 37 ++++++++--- 2 files changed, 105 insertions(+), 24 deletions(-) diff --git a/sys/compat/linuxkpi/common/src/linux_80211.c b/sys/compat/linuxkpi/common/src/linux_80211.c index 91b17769bdb5..d0b760cd6f4f 100644 --- a/sys/compat/linuxkpi/common/src/linux_80211.c +++ b/sys/compat/linuxkpi/common/src/linux_80211.c @@ -1,5 +1,5 @@ /*- - * Copyright (c) 2020-2022 The FreeBSD Foundation + * Copyright (c) 2020-2023 The FreeBSD Foundation * Copyright (c) 2020-2022 Bjoern A. Zeeb * * This software was developed by Björn Zeeb under sponsorship from @@ -792,8 +792,12 @@ lkpi_stop_hw_scan(struct lkpi_hw *lhw, struct ieee80211_vif *vif) { struct ieee80211_hw *hw; int error; + bool cancel; - if ((lhw->scan_flags & LKPI_LHW_SCAN_RUNNING) == 0) + LKPI_80211_LHW_SCAN_LOCK(lhw); + cancel = (lhw->scan_flags & LKPI_LHW_SCAN_RUNNING) != 0; + LKPI_80211_LHW_SCAN_UNLOCK(lhw); + if (!cancel) return; hw = LHW_TO_HW(lhw); @@ -802,13 +806,18 @@ lkpi_stop_hw_scan(struct lkpi_hw *lhw, struct ieee80211_vif *vif) LKPI_80211_LHW_LOCK(lhw); /* Need to cancel the scan. */ lkpi_80211_mo_cancel_hw_scan(hw, vif); + LKPI_80211_LHW_UNLOCK(lhw); /* Need to make sure we see ieee80211_scan_completed. */ - error = msleep(lhw, &lhw->mtx, 0, "lhwscanstop", hz/2); - LKPI_80211_LHW_UNLOCK(lhw); + LKPI_80211_LHW_SCAN_LOCK(lhw); + if ((lhw->scan_flags & LKPI_LHW_SCAN_RUNNING) != 0) + error = msleep(lhw, &lhw->scan_mtx, 0, "lhwscanstop", hz/2); + cancel = (lhw->scan_flags & LKPI_LHW_SCAN_RUNNING) != 0; + LKPI_80211_LHW_SCAN_UNLOCK(lhw); + IEEE80211_LOCK(lhw->ic); - if ((lhw->scan_flags & LKPI_LHW_SCAN_RUNNING) != 0) + if (cancel) ic_printf(lhw->ic, "%s: failed to cancel scan: %d (%p, %p)\n", __func__, error, lhw, vif); } @@ -935,6 +944,7 @@ lkpi_sta_scan_to_auth(struct ieee80211vap *vap, enum ieee80211_state nstate, int ni = ieee80211_ref_node(vap->iv_bss); IEEE80211_UNLOCK(vap->iv_ic); + LKPI_80211_LHW_LOCK(lhw); /* Add chanctx (or if exists, change it). */ if (vif->chanctx_conf != NULL) { @@ -1078,6 +1088,7 @@ lkpi_sta_scan_to_auth(struct ieee80211vap *vap, enum ieee80211_state nstate, int */ out: + LKPI_80211_LHW_UNLOCK(lhw); IEEE80211_LOCK(vap->iv_ic); if (ni != NULL) ieee80211_free_node(ni); @@ -1110,6 +1121,7 @@ lkpi_sta_auth_to_scan(struct ieee80211vap *vap, enum ieee80211_state nstate, int lkpi_lsta_dump(lsta, ni, __func__, __LINE__); IEEE80211_UNLOCK(vap->iv_ic); + LKPI_80211_LHW_LOCK(lhw); /* flush, drop. */ lkpi_80211_mo_flush(hw, vif, nitems(sta->txq), true); @@ -1170,6 +1182,7 @@ lkpi_sta_auth_to_scan(struct ieee80211vap *vap, enum ieee80211_state nstate, int } out: + LKPI_80211_LHW_UNLOCK(lhw); IEEE80211_LOCK(vap->iv_ic); if (ni != NULL) ieee80211_free_node(ni); @@ -1205,6 +1218,7 @@ lkpi_sta_auth_to_assoc(struct ieee80211vap *vap, enum ieee80211_state nstate, in vif = LVIF_TO_VIF(lvif); IEEE80211_UNLOCK(vap->iv_ic); + LKPI_80211_LHW_LOCK(lhw); ni = NULL; /* Finish auth. */ @@ -1252,6 +1266,7 @@ lkpi_sta_auth_to_assoc(struct ieee80211vap *vap, enum ieee80211_state nstate, in */ out: + LKPI_80211_LHW_UNLOCK(lhw); IEEE80211_LOCK(vap->iv_ic); if (ni != NULL) ieee80211_free_node(ni); @@ -1278,6 +1293,7 @@ lkpi_sta_a_to_a(struct ieee80211vap *vap, enum ieee80211_state nstate, int arg) ni = ieee80211_ref_node(vap->iv_bss); IEEE80211_UNLOCK(vap->iv_ic); + LKPI_80211_LHW_LOCK(lhw); lsta = ni->ni_drv_data; IMPROVE("event callback?"); @@ -1300,6 +1316,7 @@ lkpi_sta_a_to_a(struct ieee80211vap *vap, enum ieee80211_state nstate, int arg) lsta->in_mgd = true; } + LKPI_80211_LHW_UNLOCK(lhw); IEEE80211_LOCK(vap->iv_ic); if (ni != NULL) ieee80211_free_node(ni); @@ -1334,6 +1351,7 @@ _lkpi_sta_assoc_to_down(struct ieee80211vap *vap, enum ieee80211_state nstate, i lkpi_lsta_dump(lsta, ni, __func__, __LINE__); IEEE80211_UNLOCK(vap->iv_ic); + LKPI_80211_LHW_LOCK(lhw); /* flush, drop. */ lkpi_80211_mo_flush(hw, vif, nitems(sta->txq), true); @@ -1347,6 +1365,7 @@ _lkpi_sta_assoc_to_down(struct ieee80211vap *vap, enum ieee80211_state nstate, i lsta->in_mgd = true; } + LKPI_80211_LHW_UNLOCK(lhw); IEEE80211_LOCK(vap->iv_ic); /* Call iv_newstate first so we get potential DISASSOC packet out. */ @@ -1355,6 +1374,7 @@ _lkpi_sta_assoc_to_down(struct ieee80211vap *vap, enum ieee80211_state nstate, i goto outni; IEEE80211_UNLOCK(vap->iv_ic); + LKPI_80211_LHW_LOCK(lhw); lkpi_lsta_dump(lsta, ni, __func__, __LINE__); @@ -1438,6 +1458,7 @@ _lkpi_sta_assoc_to_down(struct ieee80211vap *vap, enum ieee80211_state nstate, i error = EALREADY; out: + LKPI_80211_LHW_UNLOCK(lhw); IEEE80211_LOCK(vap->iv_ic); outni: if (ni != NULL) @@ -1498,6 +1519,7 @@ lkpi_sta_assoc_to_run(struct ieee80211vap *vap, enum ieee80211_state nstate, int vif = LVIF_TO_VIF(lvif); IEEE80211_UNLOCK(vap->iv_ic); + LKPI_80211_LHW_LOCK(lhw); ni = NULL; IMPROVE("ponder some of this moved to ic_newassoc, scan_assoc_success, " @@ -1608,6 +1630,7 @@ lkpi_sta_assoc_to_run(struct ieee80211vap *vap, enum ieee80211_state nstate, int lkpi_80211_mo_bss_info_changed(hw, vif, &vif->bss_conf, bss_changed); out: + LKPI_80211_LHW_UNLOCK(lhw); IEEE80211_LOCK(vap->iv_ic); if (ni != NULL) ieee80211_free_node(ni); @@ -1654,6 +1677,7 @@ lkpi_sta_run_to_assoc(struct ieee80211vap *vap, enum ieee80211_state nstate, int lkpi_lsta_dump(lsta, ni, __func__, __LINE__); IEEE80211_UNLOCK(vap->iv_ic); + LKPI_80211_LHW_LOCK(lhw); /* flush, drop. */ lkpi_80211_mo_flush(hw, vif, nitems(sta->txq), true); @@ -1667,6 +1691,7 @@ lkpi_sta_run_to_assoc(struct ieee80211vap *vap, enum ieee80211_state nstate, int lsta->in_mgd = true; } + LKPI_80211_LHW_UNLOCK(lhw); IEEE80211_LOCK(vap->iv_ic); /* Call iv_newstate first so we get potential DISASSOC packet out. */ @@ -1675,6 +1700,7 @@ lkpi_sta_run_to_assoc(struct ieee80211vap *vap, enum ieee80211_state nstate, int goto outni; IEEE80211_UNLOCK(vap->iv_ic); + LKPI_80211_LHW_LOCK(lhw); lkpi_lsta_dump(lsta, ni, __func__, __LINE__); @@ -1729,6 +1755,7 @@ lkpi_sta_run_to_assoc(struct ieee80211vap *vap, enum ieee80211_state nstate, int error = EALREADY; out: + LKPI_80211_LHW_UNLOCK(lhw); IEEE80211_LOCK(vap->iv_ic); outni: if (ni != NULL) @@ -1763,6 +1790,7 @@ lkpi_sta_run_to_init(struct ieee80211vap *vap, enum ieee80211_state nstate, int lkpi_lsta_dump(lsta, ni, __func__, __LINE__); IEEE80211_UNLOCK(vap->iv_ic); + LKPI_80211_LHW_LOCK(lhw); /* flush, drop. */ lkpi_80211_mo_flush(hw, vif, nitems(sta->txq), true); @@ -1776,6 +1804,7 @@ lkpi_sta_run_to_init(struct ieee80211vap *vap, enum ieee80211_state nstate, int lsta->in_mgd = true; } + LKPI_80211_LHW_UNLOCK(lhw); IEEE80211_LOCK(vap->iv_ic); /* Call iv_newstate first so we get potential DISASSOC packet out. */ @@ -1784,6 +1813,7 @@ lkpi_sta_run_to_init(struct ieee80211vap *vap, enum ieee80211_state nstate, int goto outni; IEEE80211_UNLOCK(vap->iv_ic); + LKPI_80211_LHW_LOCK(lhw); lkpi_lsta_dump(lsta, ni, __func__, __LINE__); @@ -1890,6 +1920,7 @@ lkpi_sta_run_to_init(struct ieee80211vap *vap, enum ieee80211_state nstate, int error = EALREADY; out: + LKPI_80211_LHW_UNLOCK(lhw); IEEE80211_LOCK(vap->iv_ic); outni: if (ni != NULL) @@ -2439,6 +2470,8 @@ lkpi_ic_parent(struct ieee80211com *ic) hw = LHW_TO_HW(lhw); start_all = false; + /* IEEE80211_UNLOCK(ic); */ + LKPI_80211_LHW_LOCK(lhw); if (ic->ic_nrunning > 0) { error = lkpi_80211_mo_start(hw); if (error == 0) @@ -2446,6 +2479,8 @@ lkpi_ic_parent(struct ieee80211com *ic) } else { lkpi_80211_mo_stop(hw); } + LKPI_80211_LHW_UNLOCK(lhw); + /* IEEE80211_LOCK(ic); */ if (start_all) ieee80211_start_all(ic); @@ -2587,12 +2622,17 @@ lkpi_ic_scan_start(struct ieee80211com *ic) struct ieee80211_scan_state *ss; struct ieee80211vap *vap; int error; + bool is_hw_scan; lhw = ic->ic_softc; + LKPI_80211_LHW_SCAN_LOCK(lhw); if ((lhw->scan_flags & LKPI_LHW_SCAN_RUNNING) != 0) { /* A scan is still running. */ + LKPI_80211_LHW_SCAN_UNLOCK(lhw); return; } + is_hw_scan = (lhw->scan_flags & LKPI_LHW_SCAN_HW) != 0; + LKPI_80211_LHW_SCAN_UNLOCK(lhw); ss = ic->ic_scan; vap = ss->ss_vap; @@ -2602,7 +2642,7 @@ lkpi_ic_scan_start(struct ieee80211com *ic) } hw = LHW_TO_HW(lhw); - if ((lhw->scan_flags & LKPI_LHW_SCAN_HW) == 0) { + if (!is_hw_scan) { /* If hw_scan is cleared clear FEXT_SCAN_OFFLOAD too. */ vap->iv_flags_ext &= ~IEEE80211_FEXT_SCAN_OFFLOAD; sw_scan: @@ -2747,7 +2787,9 @@ sw_scan: * not possible. Fall back to sw scan in that case. */ if (error == 1) { + LKPI_80211_LHW_SCAN_LOCK(lhw); lhw->scan_flags &= ~LKPI_LHW_SCAN_HW; + LKPI_80211_LHW_SCAN_UNLOCK(lhw); ieee80211_start_scan(vap, IEEE80211_SCAN_ACTIVE | IEEE80211_SCAN_NOPICK | @@ -2769,13 +2811,18 @@ static void lkpi_ic_scan_end(struct ieee80211com *ic) { struct lkpi_hw *lhw; + bool is_hw_scan; lhw = ic->ic_softc; + LKPI_80211_LHW_SCAN_LOCK(lhw); if ((lhw->scan_flags & LKPI_LHW_SCAN_RUNNING) == 0) { + LKPI_80211_LHW_SCAN_UNLOCK(lhw); return; } + is_hw_scan = (lhw->scan_flags & LKPI_LHW_SCAN_HW) != 0; + LKPI_80211_LHW_SCAN_UNLOCK(lhw); - if ((lhw->scan_flags & LKPI_LHW_SCAN_HW) == 0) { + if (!is_hw_scan) { struct ieee80211_scan_state *ss; struct ieee80211vap *vap; struct ieee80211_hw *hw; @@ -2802,9 +2849,13 @@ lkpi_ic_scan_curchan(struct ieee80211_scan_state *ss, unsigned long maxdwell) { struct lkpi_hw *lhw; + bool is_hw_scan; lhw = ss->ss_ic->ic_softc; - if ((lhw->scan_flags & LKPI_LHW_SCAN_HW) == 0) + LKPI_80211_LHW_SCAN_LOCK(lhw); + is_hw_scan = (lhw->scan_flags & LKPI_LHW_SCAN_HW) != 0; + LKPI_80211_LHW_SCAN_UNLOCK(lhw); + if (!is_hw_scan) lhw->ic_scan_curchan(ss, maxdwell); } @@ -2812,9 +2863,13 @@ static void lkpi_ic_scan_mindwell(struct ieee80211_scan_state *ss) { struct lkpi_hw *lhw; + bool is_hw_scan; lhw = ss->ss_ic->ic_softc; - if ((lhw->scan_flags & LKPI_LHW_SCAN_HW) == 0) + LKPI_80211_LHW_SCAN_LOCK(lhw); + is_hw_scan = (lhw->scan_flags & LKPI_LHW_SCAN_HW) != 0; + LKPI_80211_LHW_SCAN_UNLOCK(lhw); + if (!is_hw_scan) lhw->ic_scan_mindwell(ss); } @@ -2826,6 +2881,7 @@ lkpi_ic_set_channel(struct ieee80211com *ic) struct ieee80211_channel *c; struct linuxkpi_ieee80211_channel *chan; int error; + bool hw_scan_running; lhw = ic->ic_softc; @@ -2834,8 +2890,12 @@ lkpi_ic_set_channel(struct ieee80211com *ic) return; /* If we have a hw_scan running do not switch channels. */ - if ((lhw->scan_flags & (LKPI_LHW_SCAN_RUNNING|LKPI_LHW_SCAN_HW)) == - (LKPI_LHW_SCAN_RUNNING|LKPI_LHW_SCAN_HW)) + LKPI_80211_LHW_SCAN_LOCK(lhw); + hw_scan_running = + (lhw->scan_flags & (LKPI_LHW_SCAN_RUNNING|LKPI_LHW_SCAN_HW)) == + (LKPI_LHW_SCAN_RUNNING|LKPI_LHW_SCAN_HW); + LKPI_80211_LHW_SCAN_UNLOCK(lhw); + if (hw_scan_running) return; c = ic->ic_curchan; @@ -3424,7 +3484,8 @@ linuxkpi_ieee80211_alloc_hw(size_t priv_len, const struct ieee80211_ops *ops) lhw = wiphy_priv(wiphy); lhw->ops = ops; - mtx_init(&lhw->mtx, "lhw", NULL, MTX_DEF | MTX_RECURSE); + LKPI_80211_LHW_LOCK_INIT(lhw); + LKPI_80211_LHW_SCAN_LOCK_INIT(lhw); sx_init_flags(&lhw->lvif_sx, "lhw-lvif", SX_RECURSE | SX_DUPOK); TAILQ_INIT(&lhw->lvif_head); @@ -3460,7 +3521,8 @@ linuxkpi_ieee80211_iffree(struct ieee80211_hw *hw) /* Cleanup more of lhw here or in wiphy_free()? */ sx_destroy(&lhw->lvif_sx); - mtx_destroy(&lhw->mtx); + LKPI_80211_LHW_LOCK_DESTROY(lhw); + LKPI_80211_LHW_SCAN_LOCK_DESTROY(lhw); IMPROVE(); } @@ -3867,12 +3929,12 @@ linuxkpi_ieee80211_scan_completed(struct ieee80211_hw *hw, ieee80211_scan_done(ss->ss_vap); - LKPI_80211_LHW_LOCK(lhw); + LKPI_80211_LHW_SCAN_LOCK(lhw); free(lhw->hw_req, M_LKPI80211); lhw->hw_req = NULL; lhw->scan_flags &= ~LKPI_LHW_SCAN_RUNNING; wakeup(lhw); - LKPI_80211_LHW_UNLOCK(lhw); + LKPI_80211_LHW_SCAN_UNLOCK(lhw); return; } diff --git a/sys/compat/linuxkpi/common/src/linux_80211.h b/sys/compat/linuxkpi/common/src/linux_80211.h index 4d44ca07948e..42b4192bac63 100644 --- a/sys/compat/linuxkpi/common/src/linux_80211.h +++ b/sys/compat/linuxkpi/common/src/linux_80211.h @@ -1,5 +1,5 @@ /*- - * Copyright (c) 2020-2022 The FreeBSD Foundation + * Copyright (c) 2020-2023 The FreeBSD Foundation * Copyright (c) 2020-2021 Bjoern A. Zeeb * * This software was developed by Björn Zeeb under sponsorship from @@ -173,7 +173,7 @@ struct lkpi_hw { /* name it mac80211_sc? */ TAILQ_HEAD(, lkpi_vif) lvif_head; struct sx lvif_sx; - struct mtx mtx; + struct sx sx; uint32_t txq_generation[IEEE80211_NUM_ACS]; TAILQ_HEAD(, lkpi_txq) scheduled_txqs[IEEE80211_NUM_ACS]; @@ -195,6 +195,7 @@ struct lkpi_hw { /* name it mac80211_sc? */ #define LKPI_LHW_SCAN_RUNNING 0x00000001 #define LKPI_LHW_SCAN_HW 0x00000002 uint32_t scan_flags; + struct mtx scan_mtx; int supbands; /* Number of supported bands. */ int max_rates; /* Maximum number of bitrates supported in any channel. */ @@ -218,13 +219,31 @@ struct lkpi_wiphy { #define WIPHY_TO_LWIPHY(_wiphy) container_of(_wiphy, struct lkpi_wiphy, wiphy) #define LWIPHY_TO_WIPHY(_lwiphy) (&(_lwiphy)->wiphy) - -#define LKPI_80211_LHW_LOCK(_lhw) mtx_lock(&(_lhw)->mtx) -#define LKPI_80211_LHW_UNLOCK(_lhw) mtx_unlock(&(_lhw)->mtx) -#define LKPI_80211_LHW_LOCK_ASSERT(_lhw) \ - mtx_assert(&(_lhw)->mtx, MA_OWNED) -#define LKPI_80211_LHW_UNLOCK_ASSERT(_lhw) \ - mtx_assert(&(_lhw)->mtx, MA_NOTOWNED) +#define LKPI_80211_LHW_LOCK_INIT(_lhw) \ + sx_init_flags(&(_lhw)->sx, "lhw", SX_RECURSE); +#define LKPI_80211_LHW_LOCK_DESTROY(_lhw) \ + sx_destroy(&(_lhw)->sx); +#define LKPI_80211_LHW_LOCK(_lhw) \ + sx_xlock(&(_lhw)->sx) +#define LKPI_80211_LHW_UNLOCK(_lhw) \ + sx_xunlock(&(_lhw)->sx) +#define LKPI_80211_LHW_LOCK_ASSERT(_lhw) \ + sx_assert(&(_lhw)->sx, SA_LOCKED) +#define LKPI_80211_LHW_UNLOCK_ASSERT(_lhw) \ + sx_assert(&(_lhw)->sx, SA_UNLOCKED) + +#define LKPI_80211_LHW_SCAN_LOCK_INIT(_lhw) \ + mtx_init(&(_lhw)->scan_mtx, "lhw-scan", NULL, MTX_DEF | MTX_RECURSE); +#define LKPI_80211_LHW_SCAN_LOCK_DESTROY(_lhw) \ + mtx_destroy(&(_lhw)->scan_mtx); +#define LKPI_80211_LHW_SCAN_LOCK(_lhw) \ + mtx_lock(&(_lhw)->scan_mtx) +#define LKPI_80211_LHW_SCAN_UNLOCK(_lhw) \ + mtx_unlock(&(_lhw)->scan_mtx) +#define LKPI_80211_LHW_SCAN_LOCK_ASSERT(_lhw) \ + mtx_assert(&(_lhw)->scan_mtx, MA_OWNED) +#define LKPI_80211_LHW_SCAN_UNLOCK_ASSERT(_lhw) \ + mtx_assert(&(_lhw)->scan_mtx, MA_NOTOWNED) #define LKPI_80211_LHW_LVIF_LOCK(_lhw) sx_xlock(&(_lhw)->lvif_sx) #define LKPI_80211_LHW_LVIF_UNLOCK(_lhw) sx_xunlock(&(_lhw)->lvif_sx)