From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with archive (Exim 4.43) id 1NQK8z-0006mK-Bp for mharc-grub-devel@gnu.org; Thu, 31 Dec 2009 07:28:45 -0500 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1NQK8x-0006lN-Ed for grub-devel@gnu.org; Thu, 31 Dec 2009 07:28:43 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1NQK8w-0006kk-AZ for grub-devel@gnu.org; Thu, 31 Dec 2009 07:28:42 -0500 Received: from [199.232.76.173] (port=40233 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1NQK8v-0006kY-RZ for grub-devel@gnu.org; Thu, 31 Dec 2009 07:28:41 -0500 Received: from fg-out-1718.google.com ([72.14.220.155]:36651) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1NQK8v-0004KG-Cy for grub-devel@gnu.org; Thu, 31 Dec 2009 07:28:41 -0500 Received: by fg-out-1718.google.com with SMTP id 16so785124fgg.12 for ; Thu, 31 Dec 2009 04:28:40 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from :user-agent:mime-version:to:subject:x-enigmail-version:content-type; bh=4Ycxob+SN3x+8oytjxhlWeTSD32RCIxc6zNLdY00Po0=; b=b3+kru1LRvLXIxi1rzmEXZXl5SKPsfkW8BgaUvXiigx0jxREc6qC/9/eEnynMeDM5J OmCL9ViXZpCWyv5KnQ1DY8wrdcNkavh6R5qGwDsnI419JYoBzyhw/0794srUq7W7D9+E 33AilXI/GtP9RDIelvOYwYmt/D68f3jQYUa4o= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:subject :x-enigmail-version:content-type; b=ZfuW0EDSRdvkbHVwDrzpOs2Tidn7lwnBP12tj3k9thYFSIEh3LZNEmkoPJRIwXOUha 1TYa+AV7iUipwavmgUrnZznHy+82L3FTbRjlU9s/QgUj+t3hkiK6Kz+N5oEsT1RfXu1E qzobwClSecJn1Z7wCv0aj80twdXXM33ajZ6/Y= Received: by 10.87.39.34 with SMTP id r34mr7115811fgj.79.1262262520246; Thu, 31 Dec 2009 04:28:40 -0800 (PST) Received: from debian.bg45.phnet (198-65.0-85.cust.bluewin.ch [85.0.65.198]) by mx.google.com with ESMTPS id d6sm42177762fga.14.2009.12.31.04.28.39 (version=TLSv1/SSLv3 cipher=RC4-MD5); Thu, 31 Dec 2009 04:28:39 -0800 (PST) Message-ID: <4B3C98EE.8020003@gmail.com> Date: Thu, 31 Dec 2009 13:28:30 +0100 From: =?UTF-8?B?VmxhZGltaXIgJ8+GLWNvZGVyL3BoY29kZXInIFNlcmJpbmVua28=?= User-Agent: Mozilla-Thunderbird 2.0.0.22 (X11/20091109) MIME-Version: 1.0 To: The development of GRUB 2 X-Enigmail-Version: 0.95.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="------------enig3CDBF5D8345FE59E5FC5133A" X-detected-operating-system: by monty-python.gnu.org: GNU/Linux 2.6 (newer, 2) Subject: [PATCH] Proof of concept interrupt wrapping X-BeenThere: grub-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: The development of GNU GRUB List-Id: The development of GNU GRUB List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 31 Dec 2009 12:28:43 -0000 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig3CDBF5D8345FE59E5FC5133A Content-Type: multipart/mixed; boundary="------------040103070907060105070503" This is a multi-part message in MIME format. --------------040103070907060105070503 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Hello. We were discussing with Robert how to move BIOS interrupt routines out of kernel. There are following possibilities: 1) Have a .lowmem section in every concerned module which will always be placed in low memory. Currently in experimental. Advantages: a) moving functions to modules is straightforward b) functions grow neither in size nor in complexity Disadvantages: c) needs lowmem allocators in core 2) Make every function needing bios interrupts setup its own trampoline. Due to complexity of trampolines it's not a real option 3) Have an universal routine grub_interrupt (int intno, struct grub_cpu_interrupt_regs *regs) which will be used by C routine to do the interrupt calls. This would move the complexity from asm to C. Advantages: a) simplicity in core b) complexity moved to a more readable language c) we can also rename grub_interrupt to grub_interrupt_real and make grub_interrupt dprintf registers before and after the call. This would make debugging BIOS quirks easier. Disadvantages: a) Moving functions needs effort b) C functions are probably bigger but it may be offset by possibility of inlining functions c) repeadetly changing from/to real mode is an overhead when executing multiple interrupts in series. Fortunately this condition is rare in our codebase and is only on non performance-critical parts like halting. d) Some functions aren't covered by this. At least grub_pxe_call is in this case. But we can use method 2 for them --=20 Regards Vladimir '=CF=86-coder/phcoder' Serbinenko --------------040103070907060105070503 Content-Type: text/x-diff; name="intwrap.diff" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline; filename="intwrap.diff" =3D=3D=3D modified file 'conf/i386-pc.rmk' --- conf/i386-pc.rmk 2009-12-25 22:06:52 +0000 +++ conf/i386-pc.rmk 2009-12-31 12:07:51 +0000 @@ -64,7 +64,7 @@ partition.h msdos_partition.h reader.h symbol.h term.h time.h types.h \= machine/biosdisk.h machine/boot.h machine/console.h machine/init.h \ machine/memory.h machine/loader.h machine/vga.h machine/vbe.h \ - machine/kernel.h machine/pxe.h i386/pit.h list.h handler.h command.h i1= 8n.h + machine/kernel.h machine/pxe.h i386/pit.h list.h handler.h command.h i1= 8n.h machine/int.h kernel_img_CFLAGS =3D $(COMMON_CFLAGS) $(TARGET_IMG_CFLAGS) kernel_img_ASFLAGS =3D $(COMMON_ASFLAGS) kernel_img_LDFLAGS =3D $(COMMON_LDFLAGS) $(TARGET_IMG_LDFLAGS)$(GRUB_KER= NEL_MACHINE_LINK_ADDR) $(COMMON_CFLAGS) =3D=3D=3D modified file 'disk/i386/pc/biosdisk.c' --- disk/i386/pc/biosdisk.c 2009-12-10 18:15:20 +0000 +++ disk/i386/pc/biosdisk.c 2009-12-31 12:07:51 +0000 @@ -19,6 +19,7 @@ #include #include #include +#include #include #include #include @@ -28,6 +29,59 @@ #include =20 static int cd_drive =3D 0; +static int grub_biosdisk_rw_int13_extensions (int ah, int drive, void *d= ap); + +static int grub_biosdisk_get_num_floppies (void) +{ + struct grub_cpu_int_registers regs; + int drive; + + /* reset the disk system first */ + regs.ax =3D 0; + regs.dx =3D 0; + regs.flags =3D GRUB_CPU_INT_FLAGS_DEFAULT; + + grub_cpu_interrupt (0x13, ®s); + + for (drive =3D 0; drive < 2; drive++) + { + regs.flags =3D GRUB_CPU_INT_FLAGS_DEFAULT | GRUB_CPU_INT_FLAGS_CAR= RY; + regs.dx =3D drive; + + /* call GET DISK TYPE */ + regs.ax =3D 0x1500; + grub_cpu_interrupt (0x13, ®s); + if (regs.flags & GRUB_CPU_INT_FLAGS_CARRY) + break; + + /* check if this drive exists */ + if (!(regs.ax & 0x300)) + break; + } + + return drive; +} + +/* + * Call IBM/MS INT13 Extensions (int 13 %ah=3DAH) for DRIVE. DAP + * is passed for disk address packet. If an error occurs, return + * non-zero, otherwise zero. + */ + +static int=20 +grub_biosdisk_rw_int13_extensions (int ah, int drive, void *dap) +{ + struct grub_cpu_int_registers regs; + regs.ax =3D ah << 8; + /* compute the address of disk_address_packet */ + regs.ds =3D (((grub_addr_t) dap) & 0xffff0000) >> 4; + regs.si =3D (((grub_addr_t) dap) & 0xffff); + regs.dx =3D drive; + regs.flags =3D GRUB_CPU_INT_FLAGS_DEFAULT; + + grub_cpu_interrupt (0x13, ®s); + return regs.ax >> 8; +} =20 static int grub_biosdisk_get_drive (const char *name) =3D=3D=3D modified file 'include/grub/i386/pc/biosdisk.h' --- include/grub/i386/pc/biosdisk.h 2009-06-10 21:04:23 +0000 +++ include/grub/i386/pc/biosdisk.h 2009-12-31 12:07:51 +0000 @@ -106,7 +106,6 @@ grub_uint64_t block; } __attribute__ ((packed)); =20 -int EXPORT_FUNC(grub_biosdisk_rw_int13_extensions) (int ah, int drive, v= oid *dap); int EXPORT_FUNC(grub_biosdisk_rw_standard) (int ah, int drive, int coff,= int hoff, int soff, int nsec, int segment); int EXPORT_FUNC(grub_biosdisk_check_int13_extensions) (int drive); @@ -118,7 +117,6 @@ unsigned long *cylinders, unsigned long *heads, unsigned long *sectors); -int EXPORT_FUNC(grub_biosdisk_get_num_floppies) (void); =20 void grub_biosdisk_init (void); void grub_biosdisk_fini (void); =3D=3D=3D added file 'include/grub/i386/pc/int.h' --- include/grub/i386/pc/int.h 1970-01-01 00:00:00 +0000 +++ include/grub/i386/pc/int.h 2009-12-31 12:07:51 +0000 @@ -0,0 +1,50 @@ +/* + * GRUB -- GRand Unified Bootloader + * Copyright (C) 2009 Free Software Foundation, Inc. + * + * GRUB is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by= + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * GRUB is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with GRUB. If not, see . + */ + +#ifndef GRUB_INTERRUPT_MACHINE_HEADER +#define GRUB_INTERRUPT_MACHINE_HEADER 1 + +#include + +struct grub_cpu_int_registers +{ + grub_uint16_t bx; + grub_uint16_t es; + grub_uint16_t cx; + grub_uint16_t ax; + grub_uint16_t dx; + grub_uint16_t ds; + grub_uint16_t di; + grub_uint16_t flags; + grub_uint16_t si; +}; + +#define GRUB_CPU_INT_FLAGS_CARRY 0x1 +#define GRUB_CPU_INT_FLAGS_PARITY 0x4 +#define GRUB_CPU_INT_FLAGS_ADJUST 0x10 +#define GRUB_CPU_INT_FLAGS_ZERO 0x40 +#define GRUB_CPU_INT_FLAGS_SIGN 0x80 +#define GRUB_CPU_INT_FLAGS_TRAP 0x100 +#define GRUB_CPU_INT_FLAGS_INTERRUPT 0x200 +#define GRUB_CPU_INT_FLAGS_DIRECTION 0x400 +#define GRUB_CPU_INT_FLAGS_OVERFLOW 0x800 +#define GRUB_CPU_INT_FLAGS_DEFAULT GRUB_CPU_INT_FLAGS_INTERRUPT + +void EXPORT_FUNC (grub_cpu_interrupt) (grub_uint8_t intno, struct grub_c= pu_int_registers *regs); + +#endif =3D=3D=3D modified file 'kern/i386/pc/startup.S' --- kern/i386/pc/startup.S 2009-12-25 22:01:32 +0000 +++ kern/i386/pc/startup.S 2009-12-31 12:07:51 +0000 @@ -567,44 +567,6 @@ #include "../loader.S" =20 /* - * int grub_biosdisk_rw_int13_extensions (int ah, int drive, void *dap= ) - * - * Call IBM/MS INT13 Extensions (int 13 %ah=3DAH) for DRIVE. DAP - * is passed for disk address packet. If an error occurs, return - * non-zero, otherwise zero. - */ - -FUNCTION(grub_biosdisk_rw_int13_extensions) - pushl %ebp - pushl %esi - - /* compute the address of disk_address_packet */ - movw %cx, %si - xorw %cx, %cx - shrl $4, %ecx /* save the segment to cx */ - - /* ah */ - movb %al, %dh - /* enter real mode */ - call prot_to_real - - .code16 - movb %dh, %ah - movw %cx, %ds - int $0x13 /* do the operation */ - movb %ah, %dl /* save return value */ - /* back to protected mode */ - DATA32 call real_to_prot - .code32 - - movb %dl, %al /* return value in %eax */ - - popl %esi - popl %ebp - - ret - -/* * int grub_biosdisk_rw_standard (int ah, int drive, int coff, int hof= f, * int soff, int nsec, int segment) * @@ -862,43 +824,6 @@ =20 =20 /* - * int grub_biosdisk_get_num_floppies (void) - */ -FUNCTION(grub_biosdisk_get_num_floppies) - pushl %ebp - - xorl %edx, %edx - call prot_to_real - - .code16 - /* reset the disk system first */ - int $0x13 -1: - stc - - /* call GET DISK TYPE */ - movb $0x15, %ah - int $0x13 - - jc 2f - - /* check if this drive exists */ - testb $0x3, %ah - jz 2f - - incb %dl - cmpb $2, %dl - jne 1b -2: - DATA32 call real_to_prot - .code32 - - movl %edx, %eax - popl %ebp - ret - - -/* * * grub_get_memsize(i) : return the memory size in KB. i =3D=3D 0 for c= onventional * memory, i =3D=3D 1 for extended memory @@ -2142,3 +2067,74 @@ popl %esi popl %ebp ret + +FUNCTION(grub_cpu_interrupt) + pushl %ebp + pushl %esi + pushl %edi + pushl %ebx + pushl %edx + movb %al, intno + movl %edx, %esi + + movl 0(%esi), %ebx + movl 4(%esi), %ecx + movl 8(%esi), %edx + movl 12(%esi), %edi + movw 16(%esi), %si + + call prot_to_real + .code16 + movl %edi, %eax + shrl $16, %eax + push %ax + + movl %ebx, %eax + shrl $16, %eax + movw %ax, %es +=09 + movl %edx, %eax + shrl $16, %eax + movw %ax, %ds + + movl %ecx, %eax + shrl $16, %eax + + popf + .byte 0xcd +intno:=09 + .byte 0 + + pushf + andl $0xffff, %ebx + andl $0xffff, %ecx + andl $0xffff, %edx + andl $0xffff, %edi + + shll $16, %eax + orl %eax, %ecx + + movw %ds, %ax + shll $16, %eax + orl %eax, %edx + + pop %ax + shll $16, %eax + orl %eax, %edi + + DATA32 call real_to_prot + .code32 + pushl %esi + movl 4(%esp), %esi + movl %ebx, 0(%esi) + movl %ecx, 4(%esi) + movl %edx, 8(%esi) + movl %edi, 12(%esi) + popl %eax + movw %ax, 16(%esi) + popl %eax + popl %ebx + popl %edi + popl %esi + popl %ebp + ret --------------040103070907060105070503-- --------------enig3CDBF5D8345FE59E5FC5133A Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iF4EAREKAAYFAks8mPYACgkQNak7dOguQgkHXQD+K3xGGduJ8DVHqWFt2ONo9AaQ zu7i5QT0euSJGJgZL+0BALiVZSmCLLU3whuUfirBCiBnpKI6+s3mKQ626yDELoir =yl/q -----END PGP SIGNATURE----- --------------enig3CDBF5D8345FE59E5FC5133A--