Bill Paul a944e196da MDLs are supposed to be variable size (they include an array of pages ... that describe a buffer of variable size). The problem is, allocating MDLs off the heap is slow, and it can happen that drivers will allocate lots and lots of lots of MDLs as they run. As a compromise, we now do the following: we pre-allocate a zone for MDLs big enough to describe any buffer with 16 or less pages. If IoAllocateMdl() needs a MDL for a buffer with 16 or less pages, we'll allocate it from the zone. Otherwise, we allocate it from the heap. MDLs allocate from the zone have a flag set in their mdl_flags field. When the MDL is released, IoMdlFree() will uma_zfree() the MDL if it has the MDL_ZONE_ALLOCED flag set, otherwise it will release it to the heap. The assumption is that 16 pages is a "big number" and we will rarely need MDLs larger than that. - Moved the ndis_buffer zone to subr_ntoskrnl.c from kern_ndis.c and named it mdl_zone. - Modified IoAllocateMdl() and IoFreeMdl() to use uma_zalloc() and uma_zfree() if necessary. - Made ndis_mtop() use IoAllocateMdl() instead of calling uma_zalloc() directly. Inspired by: discussion with Giridhar Pemmasani		2005-02-26 00:22:16 +00:00
..
alpha	Use a common multi-inclusion protection, and add such a	2005-02-19 21:16:48 +00:00
amd64	Remove recently added note about DEVICE_POLLING not working with SMP.	2005-02-25 22:07:51 +00:00
arm	Add the field in the md part of the struct thread required by ARM_[GET|SET]_TP.	2005-02-26 00:02:14 +00:00
boot	Document the new default init_path.	2005-02-17 11:14:45 +00:00
bsm	Add a stub audit_kevents.h, which defines exactly one audit event:	2005-02-02 14:27:36 +00:00
cam	Reference a pointer correctly when copying to it's location.	2005-02-21 00:28:36 +00:00
coda	Replace the workaround for a deadlock bug in Coda with a different	2005-02-20 23:01:57 +00:00
compat	MDLs are supposed to be variable size (they include an array of pages	2005-02-26 00:22:16 +00:00
conf	Get SYSDIR set correctly for building ports.	2005-02-25 05:34:45 +00:00
contrib	avoid sneaky double free	2005-02-25 00:16:53 +00:00
crypto	Start the dreaded NOFOO -> NO_FOO conversion.	2004-12-21 08:47:35 +00:00
ddb	Start each of the license/copyright comments with /*-	2005-01-06 01:34:41 +00:00
dev	Remove duplicate FBSDID.	2005-02-26 00:21:25 +00:00
doc
fs	remove dead code	2005-02-22 19:02:24 +00:00
gdb	/* -> /*- for copyright notices, minor format tweaks as necessary	2005-01-06 18:27:30 +00:00
geom	Correctly calculate what to do and how to retry a request to a plex when	2005-02-23 14:59:14 +00:00
gnu	move ptr deref's to after null ptr checks	2005-02-24 01:40:52 +00:00
i4b	/* -> /*- for copyright notices, minor format tweaks as necessary	2005-01-06 22:18:23 +00:00
i386	kill unused value	2005-02-25 23:06:25 +00:00
ia64	Remove acpi_perf from {ARCH}/conf/NOTES, to make tinderbox happy.	2005-02-25 07:10:37 +00:00
isa	Use the local APIC timer to drive the various kernel clocks on SMP machines	2005-02-08 20:25:07 +00:00
isofs/cd9660	Conditionalize cd9660 chattiness regarding the nature of the file system	2005-02-18 10:49:55 +00:00
kern	Remove recently added note about DEVICE_POLLING not working with SMP.	2005-02-25 22:07:51 +00:00
libkern	Add strspn() to libkern.	2005-02-10 20:39:39 +00:00
modules	The chip specific functions have been split out in their own	2005-02-25 09:49:29 +00:00
net	Change the definition of struct if_data's member ifi_epoch from wall	2005-02-25 19:46:41 +00:00
net80211	mark timestamp for pending fragments	2005-02-23 04:52:30 +00:00
netatalk	When generating a phase II ARP lookup from aarpwhohas(), use a	2005-02-22 14:37:22 +00:00
netatm	In the current world order, solisten() implements the state transition of	2005-02-21 21:58:17 +00:00
netgraph	In the current world order, solisten() implements the state transition of	2005-02-21 21:58:17 +00:00
netinet	New lines when logging.	2005-02-25 11:26:39 +00:00
netinet6	remove dead code	2005-02-25 22:58:25 +00:00
netipsec	/* -> /*- for license, minor formatting changes	2005-01-07 01:45:51 +00:00
netipx	In the current world order, solisten() implements the state transition of	2005-02-21 21:58:17 +00:00
netkey	fixed an unexpected addr/port matching failure in IPv6 SA management	2005-01-10 13:06:42 +00:00
netnatm	Mark netatm and netnatm explicitly as requiring Giant, as they still do.	2005-02-17 14:21:22 +00:00
netncp	avoid potential null ptr derefs	2005-02-23 22:44:38 +00:00
netsmb	/* -> /*- for license, minor formatting changes	2005-01-07 01:45:51 +00:00
nfs	/* -> /*- for license, minor formatting changes	2005-01-07 01:45:51 +00:00
nfs4client	Follow v_id changes in NFSv[23]	2005-02-22 15:15:28 +00:00
nfsclient	vp->v_id is a private field for the vfs namecache and it is a big mistake	2005-02-22 14:52:00 +00:00
nfsserver	Don't try to create vnode_pager objects on other filesystems vnodes,	2005-01-24 22:09:13 +00:00
opencrypto	/* -> /*- for license, minor formatting changes	2005-01-07 02:29:27 +00:00
pc98	Remove recently added note about DEVICE_POLLING not working with SMP.	2005-02-25 22:07:51 +00:00
pccard	Remove more deadwood that never got implemented in NEWCARD, since NEWCARD	2005-02-15 02:54:53 +00:00
pci	Add back 'n' that went missing in last commit	2005-02-25 03:43:43 +00:00
posix4	/* -> /*- for license, minor formatting changes	2005-01-07 02:29:27 +00:00
powerpc	Add PVO_FAKE flag to pvo entries for PG_FICTITIOUS mappings, to	2005-02-25 02:42:15 +00:00
rpc	/* -> /*- for license, minor formatting changes	2005-01-07 02:29:27 +00:00
security	Remove an accidental clearing of the new label pointer on a system V	2005-02-24 16:08:41 +00:00
sparc64	Silence witness warnings about duplicate pmap lock emitted since	2005-02-18 15:37:34 +00:00
sys	Change the definition of struct if_data's member ifi_epoch from wall	2005-02-25 19:46:41 +00:00
tools	Add VOP_FOO_APV() which takes a pointer to the vop_vector.	2005-02-08 12:54:32 +00:00
ufs	- Add VOP locking asserts in several functions that have been implicated in	2005-02-22 23:56:42 +00:00
vm	Revert the first part of revision 1.114 and modify the second part. On	2005-02-24 06:13:01 +00:00
Makefile