svn commit: r184974 - head/sys/dev/mfi

[Chagin Dmitry]

On Sun, Nov 16, 2008 at 08:51:18PM -0700, Scott Long wrote:
> Doug Ambrisko wrote:
> > Kostik Belousov writes:
> > | On Fri, Nov 14, 2008 at 09:05:45PM +0000, Doug Ambrisko wrote:
> > | > Author: ambrisko
> > | > Date: Fri Nov 14 21:05:45 2008
> > | > New Revision: 184974
> > | > URL: http://svn.freebsd.org/changeset/base/184974
> > | > 
> > | > Log:
> > | >   When running a 32bit app. on amd64, ensure the bits above 32bit
> > | >   are zero for the copyout.  Confirmed by LSI.
> > | > 
> > | > Modified:
> > | >   head/sys/dev/mfi/mfi.c
> > | > 
> > | > Modified: head/sys/dev/mfi/mfi.c
> > | > ==============================================================================
> > | > --- head/sys/dev/mfi/mfi.c	Fri Nov 14 18:09:19 2008	(r184973)
> > | > +++ head/sys/dev/mfi/mfi.c	Fri Nov 14 21:05:45 2008	(r184974)
> > | > @@ -2130,6 +2130,14 @@ mfi_ioctl(struct cdev *dev, u_long cmd, 
> > | >  			    ->mfi_frame.raw[ioc->mfi_sense_off],
> > | >  			    &sense_ptr.sense_ptr_data[0],
> > | >  			    sizeof(sense_ptr.sense_ptr_data));
> > | > +#ifdef __amd64__
> > | > +			if (cmd != MFI_CMD) {
> > | > +				/*
> > | > +				 * not 64bit native so zero out any address
> > | > +				 * over 32bit */
> > | > +				sense_ptr.high = 0;
> > | > +			}
> > | > +#endif
> > | >  			error = copyout(cm->cm_sense, sense_ptr.user_space,
> > | >  			    ioc->mfi_sense_len);
> > | >  			if (error != 0) {
> > | > @@ -2353,6 +2361,13 @@ mfi_linux_ioctl_int(struct cdev *dev, u_
> > | >                              ->lioc_frame.raw[l_ioc.lioc_sense_off],
> > | >  			    &sense_ptr.sense_ptr_data[0],
> > | >  			    sizeof(sense_ptr.sense_ptr_data));
> > | > +#ifdef __amd64__
> > | > +			/*
> > | > +			 * only 32bit Linux support so zero out any
> > | > +			 * address over 32bit
> > | > +			 */
> > | > +			sense_ptr.high = 0;
> > | > +#endif
> > | >  			error = copyout(cm->cm_sense, sense_ptr.user_space,
> > | >  			    l_ioc.lioc_sense_len);
> > | >  			if (error != 0) {
> > | 
> > | Would it make sense to perform this cut slightly more generically, by
> > | checking whether the current process is 32bit ?
> > | 
> > | We still have not grew the easy to check flag or attribute of the image,
> > | but usual practice is to compare p_sysent with corresponding sysvec,
> > | like
> > | 	if (td->td_proc->p_sysent == &ia32_freebsd_sysvec)
> > | or
> > | 	if (td->td_proc->p_sysent == &elf_linux_sysvec)
> > 
> > So far we do it based on the ioctl since the 32bit or 64bit ioctl
> > value is different.  I put in that comment for Linux since there
> > is talk/work for Linux amd64 emulation.  For 64bit Linux ioctl 
> > support we need a 64bit structure defined.  When the ioctl can't
> > be figured out then I've used the p_sysent.  Eventually, something
> > that is more generic then the #ifdef __amd64__ should be done
> > in all the drivers that do this emulation.
> > 
> > Doug A.
> 
> Something that identifies the ABI needs to be put into the proc
> structure.  This isn't the only place where such information is needed.
> Comparing against the sysent table symbol doesn't work very well because
> it requires all sysent tables be loaded, which isn't always true for the
> linux ABI.
> 
> Scott
> 

100% agree, I suggest to make somehow so:

diff --git a/sys/amd64/linux32/linux32_sysvec.c b/sys/amd64/linux32/linux32_sysvec.c
index e233700..0ea4cd8 100644
--- a/sys/amd64/linux32/linux32_sysvec.c
+++ b/sys/amd64/linux32/linux32_sysvec.c
@@ -999,6 +999,7 @@ linux32_fixlimit(struct rlimit *rl, int which)
 }
 
 struct sysentvec elf_linux_sysvec = {
+	.sv_wordsize	= __ELF_WORD_SIZE,
 	.sv_size	= LINUX_SYS_MAXSYSCALL,
 	.sv_table	= linux_sysent,
 	.sv_mask	= 0,
diff --git a/sys/sys/sysent.h b/sys/sys/sysent.h
index 0ec07a7..757b929 100644
--- a/sys/sys/sysent.h
+++ b/sys/sys/sysent.h
@@ -68,6 +68,7 @@ struct trapframe;
 struct vnode;
 
 struct sysentvec {
+	int		sv_wordsize;	/* arch wordsize */
 	int		sv_size;	/* number of entries */
 	struct sysent	*sv_table;	/* pointer to sysent */
 	u_int		sv_mask;	/* optional mask to index */

and use it like:
	if (td->td_proc->p_sysent->sv_wordsize == 32)


thnx!
-- 
Have fun!
chd