| Message ID | 20200908201012.44168-3-david@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v2,1/7] kernel/resource: make release_mem_region_adjustable() never fail | expand |
On Tue, Sep 08, 2020 at 10:10:07PM +0200, David Hildenbrand wrote: >IORESOURCE_MEM_DRIVER_MANAGED currently uses an unused PnP bit, which is >always set to 0 by hardware. This is far from beautiful (and confusing), >and the bit only applies to SYSRAM. So let's move it out of the >bus-specific (PnP) defined bits. > >We'll add another SYSRAM specific bit soon. If we ever need more bits for >other purposes, we can steal some from "desc", or reshuffle/regroup what we >have. I think you make this definition because we use IORESOURCE_SYSRAM_RAM for hotpluged memory? So we make them all in IORESOURCE_SYSRAM_XXX family? > >Cc: Andrew Morton <akpm@linux-foundation.org> >Cc: Michal Hocko <mhocko@suse.com> >Cc: Dan Williams <dan.j.williams@intel.com> >Cc: Jason Gunthorpe <jgg@ziepe.ca> >Cc: Kees Cook <keescook@chromium.org> >Cc: Ard Biesheuvel <ardb@kernel.org> >Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> >Cc: Baoquan He <bhe@redhat.com> >Cc: Wei Yang <richardw.yang@linux.intel.com> >Cc: Eric Biederman <ebiederm@xmission.com> >Cc: Thomas Gleixner <tglx@linutronix.de> >Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> >Cc: kexec@lists.infradead.org >Signed-off-by: David Hildenbrand <david@redhat.com> >--- > include/linux/ioport.h | 4 +++- > kernel/kexec_file.c | 2 +- > mm/memory_hotplug.c | 4 ++-- > 3 files changed, 6 insertions(+), 4 deletions(-) > >diff --git a/include/linux/ioport.h b/include/linux/ioport.h >index 52a91f5fa1a36..d7620d7c941a0 100644 >--- a/include/linux/ioport.h >+++ b/include/linux/ioport.h >@@ -58,6 +58,9 @@ struct resource { > #define IORESOURCE_EXT_TYPE_BITS 0x01000000 /* Resource extended types */ > #define IORESOURCE_SYSRAM 0x01000000 /* System RAM (modifier) */ > >+/* IORESOURCE_SYSRAM specific bits. */ >+#define IORESOURCE_SYSRAM_DRIVER_MANAGED 0x02000000 /* Always detected via a driver. */ >+ > #define IORESOURCE_EXCLUSIVE 0x08000000 /* Userland may not map this resource */ > > #define IORESOURCE_DISABLED 0x10000000 >@@ -103,7 +106,6 @@ struct resource { > #define IORESOURCE_MEM_32BIT (3<<3) > #define IORESOURCE_MEM_SHADOWABLE (1<<5) /* dup: IORESOURCE_SHADOWABLE */ > #define IORESOURCE_MEM_EXPANSIONROM (1<<6) >-#define IORESOURCE_MEM_DRIVER_MANAGED (1<<7) > > /* PnP I/O specific bits (IORESOURCE_BITS) */ > #define IORESOURCE_IO_16BIT_ADDR (1<<0) >diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c >index ca40bef75a616..dfeeed1aed084 100644 >--- a/kernel/kexec_file.c >+++ b/kernel/kexec_file.c >@@ -520,7 +520,7 @@ static int locate_mem_hole_callback(struct resource *res, void *arg) > /* Returning 0 will take to next memory range */ > > /* Don't use memory that will be detected and handled by a driver. */ >- if (res->flags & IORESOURCE_MEM_DRIVER_MANAGED) >+ if (res->flags & IORESOURCE_SYSRAM_DRIVER_MANAGED) > return 0; > > if (sz < kbuf->memsz) >diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c >index 4c47b68a9f4b5..8e1cd18b5cf14 100644 >--- a/mm/memory_hotplug.c >+++ b/mm/memory_hotplug.c >@@ -105,7 +105,7 @@ static struct resource *register_memory_resource(u64 start, u64 size, > unsigned long flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; > > if (strcmp(resource_name, "System RAM")) >- flags |= IORESOURCE_MEM_DRIVER_MANAGED; >+ flags |= IORESOURCE_SYSRAM_DRIVER_MANAGED; > > /* > * Make sure value parsed from 'mem=' only restricts memory adding >@@ -1160,7 +1160,7 @@ EXPORT_SYMBOL_GPL(add_memory); > * > * For this memory, no entries in /sys/firmware/memmap ("raw firmware-provided > * memory map") are created. Also, the created memory resource is flagged >- * with IORESOURCE_MEM_DRIVER_MANAGED, so in-kernel users can special-case >+ * with IORESOURCE_SYSRAM_DRIVER_MANAGED, so in-kernel users can special-case > * this memory as well (esp., not place kexec images onto it). > * > * The resource_name (visible via /proc/iomem) has to have the format >-- >2.26.2
On 15.09.20 04:20, Wei Yang wrote: > On Tue, Sep 08, 2020 at 10:10:07PM +0200, David Hildenbrand wrote: >> IORESOURCE_MEM_DRIVER_MANAGED currently uses an unused PnP bit, which is >> always set to 0 by hardware. This is far from beautiful (and confusing), >> and the bit only applies to SYSRAM. So let's move it out of the >> bus-specific (PnP) defined bits. >> >> We'll add another SYSRAM specific bit soon. If we ever need more bits for >> other purposes, we can steal some from "desc", or reshuffle/regroup what we >> have. > > I think you make this definition because we use IORESOURCE_SYSRAM_RAM for > hotpluged memory? So we make them all in IORESOURCE_SYSRAM_XXX family? Yeah, to specify based on the extended MEM type SYSRAM. Because it really only applies to that. -- Thanks, David / dhildenb
diff --git a/include/linux/ioport.h b/include/linux/ioport.h index 52a91f5fa1a36..d7620d7c941a0 100644 --- a/include/linux/ioport.h +++ b/include/linux/ioport.h @@ -58,6 +58,9 @@ struct resource { #define IORESOURCE_EXT_TYPE_BITS 0x01000000 /* Resource extended types */ #define IORESOURCE_SYSRAM 0x01000000 /* System RAM (modifier) */ +/* IORESOURCE_SYSRAM specific bits. */ +#define IORESOURCE_SYSRAM_DRIVER_MANAGED 0x02000000 /* Always detected via a driver. */ + #define IORESOURCE_EXCLUSIVE 0x08000000 /* Userland may not map this resource */ #define IORESOURCE_DISABLED 0x10000000 @@ -103,7 +106,6 @@ struct resource { #define IORESOURCE_MEM_32BIT (3<<3) #define IORESOURCE_MEM_SHADOWABLE (1<<5) /* dup: IORESOURCE_SHADOWABLE */ #define IORESOURCE_MEM_EXPANSIONROM (1<<6) -#define IORESOURCE_MEM_DRIVER_MANAGED (1<<7) /* PnP I/O specific bits (IORESOURCE_BITS) */ #define IORESOURCE_IO_16BIT_ADDR (1<<0) diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c index ca40bef75a616..dfeeed1aed084 100644 --- a/kernel/kexec_file.c +++ b/kernel/kexec_file.c @@ -520,7 +520,7 @@ static int locate_mem_hole_callback(struct resource *res, void *arg) /* Returning 0 will take to next memory range */ /* Don't use memory that will be detected and handled by a driver. */ - if (res->flags & IORESOURCE_MEM_DRIVER_MANAGED) + if (res->flags & IORESOURCE_SYSRAM_DRIVER_MANAGED) return 0; if (sz < kbuf->memsz) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 4c47b68a9f4b5..8e1cd18b5cf14 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -105,7 +105,7 @@ static struct resource *register_memory_resource(u64 start, u64 size, unsigned long flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; if (strcmp(resource_name, "System RAM")) - flags |= IORESOURCE_MEM_DRIVER_MANAGED; + flags |= IORESOURCE_SYSRAM_DRIVER_MANAGED; /* * Make sure value parsed from 'mem=' only restricts memory adding @@ -1160,7 +1160,7 @@ EXPORT_SYMBOL_GPL(add_memory); * * For this memory, no entries in /sys/firmware/memmap ("raw firmware-provided * memory map") are created. Also, the created memory resource is flagged - * with IORESOURCE_MEM_DRIVER_MANAGED, so in-kernel users can special-case + * with IORESOURCE_SYSRAM_DRIVER_MANAGED, so in-kernel users can special-case * this memory as well (esp., not place kexec images onto it). * * The resource_name (visible via /proc/iomem) has to have the format
IORESOURCE_MEM_DRIVER_MANAGED currently uses an unused PnP bit, which is always set to 0 by hardware. This is far from beautiful (and confusing), and the bit only applies to SYSRAM. So let's move it out of the bus-specific (PnP) defined bits. We'll add another SYSRAM specific bit soon. If we ever need more bits for other purposes, we can steal some from "desc", or reshuffle/regroup what we have. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Kees Cook <keescook@chromium.org> Cc: Ard Biesheuvel <ardb@kernel.org> Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Baoquan He <bhe@redhat.com> Cc: Wei Yang <richardw.yang@linux.intel.com> Cc: Eric Biederman <ebiederm@xmission.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: kexec@lists.infradead.org Signed-off-by: David Hildenbrand <david@redhat.com> --- include/linux/ioport.h | 4 +++- kernel/kexec_file.c | 2 +- mm/memory_hotplug.c | 4 ++-- 3 files changed, 6 insertions(+), 4 deletions(-)