• Ingo Molnar's avatar
    x86/boot/e820: Simplify the e820__update_table() interface · f9748fa0
    Ingo Molnar authored
    The e820__update_table() parameters are pretty complex:
    
      arch/x86/include/asm/e820/api.h:extern int  e820__update_table(struct e820_entry *biosmap, int max_nr_map, u32 *pnr_map);
    
    But 90% of the usage is trivial:
    
      arch/x86/kernel/e820.c:	if (e820__update_table(e820_table->entries, ARRAY_SIZE(e820_table->entries), &e820_table->nr_entries))
      arch/x86/kernel/e820.c:	e820__update_table(e820_table->entries, ARRAY_SIZE(e820_table->entries), &e820_table->nr_entries);
      arch/x86/kernel/e820.c:	e820__update_table(e820_table->entries, ARRAY_SIZE(e820_table->entries), &e820_table->nr_entries);
      arch/x86/kernel/e820.c:		if (e820__update_table(e820_table->entries, ARRAY_SIZE(e820_table->entries), &e820_table->nr_entries) < 0)
      arch/x86/kernel/e820.c:	e820__update_table(boot_params.e820_table, ARRAY_SIZE(boot_params.e820_table), &new_nr);
      arch/x86/kernel/early-quirks.c:	e820__update_table(e820_table->entries, ARRAY_SIZE(e820_table->entries), &e820_table->nr_entries);
      arch/x86/kernel/setup.c:	e820__update_table(e820_table->entries, ARRAY_SIZE(e820_table->entries), &e820_table->nr_entries);
      arch/x86/kernel/setup.c:		e820__update_table(e820_table->entries, ARRAY_SIZE(e820_table->entries), &e820_table->nr_entries);
      arch/x86/platform/efi/efi.c:	e820__update_table(e820_table->entries, ARRAY_SIZE(e820_table->entries), &e820_table->nr_entries);
      arch/x86/xen/setup.c:	e820__update_table(xen_e820_table.entries, ARRAY_SIZE(xen_e820_table.entries),
      arch/x86/xen/setup.c:	e820__update_table(e820_table->entries, ARRAY_SIZE(e820_table->entries), &e820_table->nr_entries);
      arch/x86/xen/setup.c:	e820__update_table(xen_e820_table.entries, ARRAY_SIZE(xen_e820_table.entries),
    
    as it only uses an exiting struct e820_table's entries array, its size and
    its current number of entries as input and output arguments.
    
    Only one use is non-trivial:
    
      arch/x86/kernel/e820.c:	e820__update_table(boot_params.e820_table, ARRAY_SIZE(boot_params.e820_table), &new_nr);
    
    ... which call updates the E820 table in the zeropage in-situ, and the layout there does not
    match that of 'struct e820_table' (in particular nr_entries is at a different offset,
    hardcoded by the boot protocol).
    
    Simplify all this by introducing a low level __e820__update_table() API that
    the zeropage update call can use, and simplifying the main e820__update_table()
    call signature down to:
    
    	int e820__update_table(struct e820_table *table);
    
    This visibly simplifies all the call sites:
    
      arch/x86/include/asm/e820/api.h:extern int  e820__update_table(struct e820_table *table);
      arch/x86/include/asm/e820/types.h: * call to e820__update_table() to remove duplicates.  The allowance
      arch/x86/kernel/e820.c: * The return value from e820__update_table() is zero if it
      arch/x86/kernel/e820.c:int __init e820__update_table(struct e820_table *table)
      arch/x86/kernel/e820.c:	if (e820__update_table(e820_table))
      arch/x86/kernel/e820.c:	e820__update_table(e820_table_firmware);
      arch/x86/kernel/e820.c:	e820__update_table(e820_table);
      arch/x86/kernel/e820.c:	e820__update_table(e820_table);
      arch/x86/kernel/e820.c:		if (e820__update_table(e820_table) < 0)
      arch/x86/kernel/early-quirks.c:	e820__update_table(e820_table);
      arch/x86/kernel/setup.c:	e820__update_table(e820_table);
      arch/x86/kernel/setup.c:		e820__update_table(e820_table);
      arch/x86/platform/efi/efi.c:	e820__update_table(e820_table);
      arch/x86/xen/setup.c:	e820__update_table(&xen_e820_table);
      arch/x86/xen/setup.c:	e820__update_table(e820_table);
      arch/x86/xen/setup.c:	e820__update_table(&xen_e820_table);
    
    No change in functionality.
    
    Cc: Alex Thorlton <athorlton@sgi.com>
    Cc: Andy Lutomirski <luto@kernel.org>
    Cc: Borislav Petkov <bp@alien8.de>
    Cc: Brian Gerst <brgerst@gmail.com>
    Cc: Dan Williams <dan.j.williams@intel.com>
    Cc: Denys Vlasenko <dvlasenk@redhat.com>
    Cc: H. Peter Anvin <hpa@zytor.com>
    Cc: Huang, Ying <ying.huang@intel.com>
    Cc: Josh Poimboeuf <jpoimboe@redhat.com>
    Cc: Juergen Gross <jgross@suse.com>
    Cc: Linus Torvalds <torvalds@linux-foundation.org>
    Cc: Paul Jackson <pj@sgi.com>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Rafael J. Wysocki <rjw@sisk.pl>
    Cc: Tejun Heo <tj@kernel.org>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Cc: Wei Yang <richard.weiyang@gmail.com>
    Cc: Yinghai Lu <yinghai@kernel.org>
    Cc: linux-kernel@vger.kernel.org
    Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
    f9748fa0
efi.c 26.6 KB