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| author | Mark Johnston <markj@FreeBSD.org> | 2023-11-06 19:57:56 +0000 |
|---|---|---|
| committer | Mark Johnston <markj@FreeBSD.org> | 2023-11-06 19:57:56 +0000 |
| commit | 725962a9f4c050b21488edd58d317e87c76d6f66 (patch) | |
| tree | d2b699c47e048450a551c331af9671666949b53d | |
| parent | 2ffd30f7ee15c87ee092cbac6a4438bcb3af923c (diff) | |
| download | src-725962a9f4c050b21488edd58d317e87c76d6f66.tar.gz src-725962a9f4c050b21488edd58d317e87c76d6f66.zip | |
e6000sw: Fix locking in miibus_{read,write}reg implementations
Commit 469290648005e13b819a19353032ca53dda4378f made e6000sw's
implementation of miibus_(read|write)reg assume that the softc lock is
held. I presume that is to avoid lock recursion in e6000sw_attach() ->
e6000sw_attach_miibus() -> mii_attach() -> MIIBUS_READREG().
However, the lock assertion in e6000sw_readphy_locked() can fail if a
different driver uses the interface to probe registers. Work around the
problem by providing implementations which lock the softc if it is not
already locked.
PR: 274795
Fixes: 469290648005 ("e6000sw: add readphy and writephy wrappers")
Reviewed by: kp, imp
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D42466
| -rw-r--r-- | sys/dev/etherswitch/e6000sw/e6000sw.c | 31 |
1 files changed, 19 insertions, 12 deletions
diff --git a/sys/dev/etherswitch/e6000sw/e6000sw.c b/sys/dev/etherswitch/e6000sw/e6000sw.c index 768d1b927e3e..95f1a2e96db6 100644 --- a/sys/dev/etherswitch/e6000sw/e6000sw.c +++ b/sys/dev/etherswitch/e6000sw/e6000sw.c @@ -66,6 +66,7 @@ MALLOC_DEFINE(M_E6000SW, "e6000sw", "e6000sw switch"); #define E6000SW_UNLOCK(_sc) sx_unlock(&(_sc)->sx) #define E6000SW_LOCK_ASSERT(_sc, _what) sx_assert(&(_sc)->sx, (_what)) #define E6000SW_TRYLOCK(_sc) sx_tryxlock(&(_sc)->sx) +#define E6000SW_LOCKED(_sc) sx_xlocked(&(_sc)->sx) #define E6000SW_WAITREADY(_sc, _reg, _bit) \ e6000sw_waitready((_sc), REG_GLOBAL, (_reg), (_bit)) #define E6000SW_WAITREADY2(_sc, _reg, _bit) \ @@ -169,8 +170,8 @@ static device_method_t e6000sw_methods[] = { DEVMETHOD(bus_add_child, device_add_child_ordered), /* mii interface */ - DEVMETHOD(miibus_readreg, e6000sw_readphy_locked), - DEVMETHOD(miibus_writereg, e6000sw_writephy_locked), + DEVMETHOD(miibus_readreg, e6000sw_readphy), + DEVMETHOD(miibus_writereg, e6000sw_writephy), /* etherswitch interface */ DEVMETHOD(etherswitch_getinfo, e6000sw_getinfo), @@ -744,17 +745,20 @@ e6000sw_write_xmdio(device_t dev, int phy, int devaddr, int devreg, int val) return (0); } -static int e6000sw_readphy(device_t dev, int phy, int reg) +static int +e6000sw_readphy(device_t dev, int phy, int reg) { e6000sw_softc_t *sc; - int ret; + int locked, ret; sc = device_get_softc(dev); - E6000SW_LOCK_ASSERT(sc, SA_UNLOCKED); - E6000SW_LOCK(sc); + locked = E6000SW_LOCKED(sc); + if (!locked) + E6000SW_LOCK(sc); ret = e6000sw_readphy_locked(dev, phy, reg); - E6000SW_UNLOCK(sc); + if (!locked) + E6000SW_UNLOCK(sc); return (ret); } @@ -795,17 +799,20 @@ e6000sw_readphy_locked(device_t dev, int phy, int reg) return (val & PHY_DATA_MASK); } -static int e6000sw_writephy(device_t dev, int phy, int reg, int data) +static int +e6000sw_writephy(device_t dev, int phy, int reg, int data) { e6000sw_softc_t *sc; - int ret; + int locked, ret; sc = device_get_softc(dev); - E6000SW_LOCK_ASSERT(sc, SA_UNLOCKED); - E6000SW_LOCK(sc); + locked = E6000SW_LOCKED(sc); + if (!locked) + E6000SW_LOCK(sc); ret = e6000sw_writephy_locked(dev, phy, reg, data); - E6000SW_UNLOCK(sc); + if (!locked) + E6000SW_UNLOCK(sc); return (ret); } |