diff options
Diffstat (limited to 'usr/src/uts/common/io/dls')
| -rw-r--r-- | usr/src/uts/common/io/dls/dls.c | 24 | ||||
| -rw-r--r-- | usr/src/uts/common/io/dls/dls_link.c | 4 | ||||
| -rw-r--r-- | usr/src/uts/common/io/dls/dls_mgmt.c | 106 |
3 files changed, 89 insertions, 45 deletions
diff --git a/usr/src/uts/common/io/dls/dls.c b/usr/src/uts/common/io/dls/dls.c index 064217c8f2..53450a45d1 100644 --- a/usr/src/uts/common/io/dls/dls.c +++ b/usr/src/uts/common/io/dls/dls.c @@ -19,7 +19,7 @@ * CDDL HEADER END */ /* - * Copyright 2008 Sun Microsystems, Inc. All rights reserved. + * Copyright 2009 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ @@ -607,14 +607,6 @@ dls_mac_active_set(dls_link_t *dlp) * Set the function to start receiving packets. */ mac_rx_set(dlp->dl_mch, i_dls_link_rx, dlp); - - /* - * We've got a MAC client for this link now. - * Push down the flows that were defined on this link - * hitherto. The flows are added to the active flow table - * and SRS, softrings etc. are created as needed. - */ - mac_link_init_flows(dlp->dl_mch); } dlp->dl_nactive++; return (0); @@ -625,20 +617,6 @@ dls_mac_active_clear(dls_link_t *dlp) { if (--dlp->dl_nactive == 0) { ASSERT(dlp->dl_mah != NULL); - /* - * We would have initialized subflows etc. only if we - * brought up the primary client and set the unicast - * unicast address etc. Deactivate the flows. The flow - * entry will be removed from the active flow tables, - * and the associated SRS, softrings etc will be - * deleted. But the flow entry itself won't be - * destroyed, instead it will continue to be - * archived off the the global flow hash list, for a - * possible future activation when say - * IP is plumbed again - */ - - mac_link_release_flows(dlp->dl_mch); (void) mac_unicast_remove(dlp->dl_mch, dlp->dl_mah); dlp->dl_mah = NULL; mac_rx_clear(dlp->dl_mch); diff --git a/usr/src/uts/common/io/dls/dls_link.c b/usr/src/uts/common/io/dls/dls_link.c index 852b87d24b..85aee7fe86 100644 --- a/usr/src/uts/common/io/dls/dls_link.c +++ b/usr/src/uts/common/io/dls/dls_link.c @@ -19,7 +19,7 @@ * CDDL HEADER END */ /* - * Copyright 2008 Sun Microsystems, Inc. All rights reserved. + * Copyright 2009 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ @@ -36,7 +36,7 @@ #include <sys/atomic.h> static kmem_cache_t *i_dls_link_cachep; -static mod_hash_t *i_dls_link_hash; +mod_hash_t *i_dls_link_hash; static uint_t i_dls_link_count; #define LINK_HASHSZ 67 /* prime */ diff --git a/usr/src/uts/common/io/dls/dls_mgmt.c b/usr/src/uts/common/io/dls/dls_mgmt.c index bb922423b3..576e13ac2c 100644 --- a/usr/src/uts/common/io/dls/dls_mgmt.c +++ b/usr/src/uts/common/io/dls/dls_mgmt.c @@ -19,7 +19,7 @@ * CDDL HEADER END */ /* - * Copyright 2008 Sun Microsystems, Inc. All rights reserved. + * Copyright 2009 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ @@ -60,10 +60,15 @@ boolean_t devnet_need_rebuild; /* Upcall door handle */ static door_handle_t dls_mgmt_dh = NULL; -#define DD_CONDEMNED 0x1 +#define DD_CONDEMNED 0x1 +#define DD_KSTAT_CHANGING 0x2 /* * This structure is used to keep the <linkid, macname> mapping. + * This structure itself is not protected by the mac perimeter, but is + * protected by the dd_mutex and i_dls_devnet_lock. Thus most of the + * functions manipulating this structure such as dls_devnet_set/unset etc. + * may be called while not holding the mac perimeter. */ typedef struct dls_devnet_s { datalink_id_t dd_linkid; @@ -614,6 +619,11 @@ dls_devnet_rele_link(dls_dl_handle_t dlh, dls_link_t *dlp) /* * Query the "link" kstats. + * + * We may be called from the kstat subsystem in an arbitrary context. + * If the caller is the stack, the context could be an upcall data + * thread. Hence we can't acquire the mac perimeter in this function + * for fear of deadlock. */ static int dls_devnet_stat_update(kstat_t *ksp, int rw) @@ -621,21 +631,34 @@ dls_devnet_stat_update(kstat_t *ksp, int rw) dls_devnet_t *ddp = ksp->ks_private; dls_link_t *dlp; int err; - mac_perim_handle_t mph; - err = mac_perim_enter_by_macname(ddp->dd_mac, &mph); - if (err != 0) - return (err); + /* + * Check the link is being renamed or if the link is going away + * before incrementing dd_tref which in turn prevents the link + * from being renamed or deleted until we finish. + */ + mutex_enter(&ddp->dd_mutex); + if (ddp->dd_flags & (DD_CONDEMNED | DD_KSTAT_CHANGING)) { + mutex_exit(&ddp->dd_mutex); + return (ENOENT); + } + ddp->dd_tref++; + mutex_exit(&ddp->dd_mutex); - err = dls_link_hold(ddp->dd_mac, &dlp); - if (err != 0) { - mac_perim_exit(mph); - return (err); + /* + * If a device detach happens at this time, it will block in + * dls_devnet_unset since the dd_tref has been bumped up above. So the + * access to 'dlp' is safe even though we don't hold the mac perimeter. + */ + if (mod_hash_find(i_dls_link_hash, (mod_hash_key_t)ddp->dd_mac, + (mod_hash_val_t *)&dlp) != 0) { + dls_devnet_rele_tmp(ddp); + return (ENOENT); } err = dls_stat_update(ksp, dlp, rw); - dls_link_rele(dlp); - mac_perim_exit(mph); + + dls_devnet_rele_tmp(ddp); return (err); } @@ -707,6 +730,7 @@ dls_devnet_set(const char *macname, datalink_id_t linkid, dls_devnet_t **ddpp) dls_devnet_t *ddp = NULL; datalink_class_t class; int err; + boolean_t stat_create = B_FALSE; rw_enter(&i_dls_devnet_lock, RW_WRITER); if ((err = mod_hash_find(i_dls_devnet_hash, @@ -748,8 +772,7 @@ newphys: (mod_hash_key_t)(uintptr_t)linkid, (mod_hash_val_t)ddp) == 0); devnet_need_rebuild = B_TRUE; - dls_devnet_stat_create(ddp); - + stat_create = B_TRUE; mutex_enter(&ddp->dd_mutex); if (!ddp->dd_prop_loaded && (ddp->dd_prop_taskid == NULL)) { ddp->dd_prop_taskid = taskq_dispatch(system_taskq, @@ -761,6 +784,20 @@ newphys: err = 0; done: rw_exit(&i_dls_devnet_lock); + /* + * It is safe to drop the i_dls_devnet_lock at this point. In the case + * of physical devices, the softmac framework will fail the device + * detach based on the smac_state or smac_hold_cnt. Other cases like + * vnic and aggr use their own scheme to serialize creates and deletes + * and ensure that *ddp is valid. + * + * The kstat subsystem holds its own locks (rather perimeter) before + * calling the ks_update (dls_devnet_stat_update) entry point which + * in turn grabs the i_dls_devnet_lock. So the lock hierarchy is + * kstat locks -> i_dls_devnet_lock. + */ + if (stat_create) + dls_devnet_stat_create(ddp); if (err == 0 && ddpp != NULL) *ddpp = ddp; return (err); @@ -815,7 +852,6 @@ dls_devnet_unset(const char *macname, datalink_id_t *id, boolean_t wait) VERIFY(mod_hash_remove(i_dls_devnet_id_hash, (mod_hash_key_t)(uintptr_t)ddp->dd_linkid, &val) == 0); - dls_devnet_stat_destroy(ddp); devnet_need_rebuild = B_TRUE; } rw_exit(&i_dls_devnet_lock); @@ -830,6 +866,9 @@ dls_devnet_unset(const char *macname, datalink_id_t *id, boolean_t wait) ASSERT(ddp->dd_tref == 0 && ddp->dd_prop_taskid == NULL); } + if (ddp->dd_linkid != DATALINK_INVALID_LINKID) + dls_devnet_stat_destroy(ddp); + ddp->dd_prop_loaded = B_FALSE; ddp->dd_linkid = DATALINK_INVALID_LINKID; ddp->dd_zid = GLOBAL_ZONEID; @@ -1112,6 +1151,7 @@ dls_devnet_rename(datalink_id_t id1, datalink_id_t id2, const char *link) mac_perim_handle_t mph = NULL; mac_handle_t mh; mod_hash_val_t val; + boolean_t clear_dd_flag = B_FALSE; /* * In the second case, id2 must be a REMOVED physical link. @@ -1134,8 +1174,10 @@ dls_devnet_rename(datalink_id_t id1, datalink_id_t id2, const char *link) * mac perimeter, hence enter the perimeter first. This also waits * for the property loading to finish. */ - if ((err = mac_perim_enter_by_linkid(id1, &mph)) != 0) - goto done; + if ((err = mac_perim_enter_by_linkid(id1, &mph)) != 0) { + softmac_rele_device(ddh); + return (err); + } rw_enter(&i_dls_devnet_lock, RW_WRITER); if ((err = mod_hash_find(i_dls_devnet_id_hash, @@ -1146,13 +1188,22 @@ dls_devnet_rename(datalink_id_t id1, datalink_id_t id2, const char *link) } /* - * Return EBUSY if any applications have this link open. + * Return EBUSY if any applications have this link open or if any + * thread is currently accessing the link kstats. Then set the + * DD_KSTAT_CHANGING flag to prevent any access to the kstats + * while we delete and recreate kstats below. */ + mutex_enter(&ddp->dd_mutex); if (ddp->dd_ref > 1) { + mutex_exit(&ddp->dd_mutex); err = EBUSY; goto done; } + ddp->dd_flags |= DD_KSTAT_CHANGING; + clear_dd_flag = B_TRUE; + mutex_exit(&ddp->dd_mutex); + if (id2 == DATALINK_INVALID_LINKID) { (void) strlcpy(linkname, link, sizeof (linkname)); @@ -1225,11 +1276,21 @@ dls_devnet_rename(datalink_id_t id1, datalink_id_t id2, const char *link) done: /* * Change the name of the kstat based on the new link name. + * We can't hold the i_dls_devnet_lock across calls to the kstat + * subsystem. Instead the DD_KSTAT_CHANGING flag set above in this + * function prevents any access to the dd_ksp while we delete and + * recreate it below. */ + rw_exit(&i_dls_devnet_lock); if (err == 0) dls_devnet_stat_rename(ddp, linkname); - rw_exit(&i_dls_devnet_lock); + if (clear_dd_flag) { + mutex_enter(&ddp->dd_mutex); + ddp->dd_flags &= ~DD_KSTAT_CHANGING; + mutex_exit(&ddp->dd_mutex); + } + if (mph != NULL) mac_perim_exit(mph); softmac_rele_device(ddh); @@ -1388,6 +1449,11 @@ dls_devnet_create(mac_handle_t mh, datalink_id_t linkid) int err; mac_perim_handle_t mph; + /* + * Holding the mac perimeter ensures that the downcall from the + * dlmgmt daemon which does the property loading does not proceed + * until we relinquish the perimeter. + */ mac_perim_enter_by_mh(mh, &mph); /* @@ -1400,8 +1466,8 @@ dls_devnet_create(mac_handle_t mh, datalink_id_t linkid) return (err); } if ((err = dls_link_hold_create(mac_name(mh), &dlp)) != 0) { - (void) dls_devnet_unset(mac_name(mh), &linkid, B_TRUE); mac_perim_exit(mph); + (void) dls_devnet_unset(mac_name(mh), &linkid, B_TRUE); return (err); } mac_perim_exit(mph); |