| Message ID | 1405955204-10438-1-git-send-email-pbonzini@redhat.com |
|---|---|
| State | New |
| Headers | show |
On Mon, Jul 21, 2014 at 05:06:44PM +0200, Paolo Bonzini wrote: > Devices that use address_space_rw to write large areas to memory > (as opposed to address_space_map/unmap) were broken with respect > to migration since fe680d0 (exec: Limit translation limiting in > address_space_translate to xen, 2014-05-07). Such devices include > IDE CD-ROMs. > > The reason is that invalidate_and_set_dirty (called by address_space_rw > but not address_space_map/unmap) was only setting the dirty bit for > the first page in the translation. > > To fix this, introduce cpu_physical_memory_set_dirty_range_nocode that > is the same as cpu_physical_memory_set_dirty_range except it does not > muck with the DIRTY_MEMORY_CODE bitmap. This function can be used if > the caller invalidates translations with tb_invalidate_phys_page_range. > > There is another difference between cpu_physical_memory_set_dirty_range > and cpu_physical_memory_set_dirty_flag; the former includes a call > to xen_modified_memory. This is handled separately in > invalidate_and_set_dirty, and is not needed in other callers of > cpu_physical_memory_set_dirty_range_nocode, so leave it alone. > > Just one nit: now that invalidate_and_set_dirty takes care of handling > multiple pages, there is no need for address_space_unmap to wrap it > in a loop. In fact that loop would now be O(n^1). > > Reported-by: Dave Gilbert <dgilbert@redhat.com> > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> > --- > exec.c | 20 ++++---------------- > include/exec/ram_addr.h | 11 +++++++++++ > 2 files changed, 15 insertions(+), 16 deletions(-) > > diff --git a/exec.c b/exec.c > index 5a2a25e..765bd94 100644 > --- a/exec.c > +++ b/exec.c > @@ -1568,8 +1568,7 @@ static void notdirty_mem_write(void *opaque, hwaddr ram_addr, > default: > abort(); > } > - cpu_physical_memory_set_dirty_flag(ram_addr, DIRTY_MEMORY_MIGRATION); > - cpu_physical_memory_set_dirty_flag(ram_addr, DIRTY_MEMORY_VGA); > + cpu_physical_memory_set_dirty_range_nocode(ram_addr, size); > /* we remove the notdirty callback only if the code has been > flushed */ > if (!cpu_physical_memory_is_clean(ram_addr)) { > @@ -1978,8 +1977,7 @@ static void invalidate_and_set_dirty(hwaddr addr, > /* invalidate code */ > tb_invalidate_phys_page_range(addr, addr + length, 0); > /* set dirty bit */ > - cpu_physical_memory_set_dirty_flag(addr, DIRTY_MEMORY_VGA); > - cpu_physical_memory_set_dirty_flag(addr, DIRTY_MEMORY_MIGRATION); > + cpu_physical_memory_set_dirty_range_nocode(addr, length); > } > xen_modified_memory(addr, length); > } > @@ -2335,15 +2333,7 @@ void address_space_unmap(AddressSpace *as, void *buffer, hwaddr len, > mr = qemu_ram_addr_from_host(buffer, &addr1); > assert(mr != NULL); > if (is_write) { > - while (access_len) { > - unsigned l; > - l = TARGET_PAGE_SIZE; > - if (l > access_len) > - l = access_len; > - invalidate_and_set_dirty(addr1, l); > - addr1 += l; > - access_len -= l; > - } > + invalidate_and_set_dirty(addr1, access_len); > } > if (xen_enabled()) { > xen_invalidate_map_cache_entry(buffer); > @@ -2581,9 +2571,7 @@ void stl_phys_notdirty(AddressSpace *as, hwaddr addr, uint32_t val) > /* invalidate code */ > tb_invalidate_phys_page_range(addr1, addr1 + 4, 0); > /* set dirty bit */ > - cpu_physical_memory_set_dirty_flag(addr1, > - DIRTY_MEMORY_MIGRATION); > - cpu_physical_memory_set_dirty_flag(addr1, DIRTY_MEMORY_VGA); > + cpu_physical_memory_set_dirty_range_nocode(addr1, 4); > } > } > } > diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h > index e9eb831..6593be1 100644 > --- a/include/exec/ram_addr.h > +++ b/include/exec/ram_addr.h > @@ -71,6 +71,17 @@ static inline void cpu_physical_memory_set_dirty_flag(ram_addr_t addr, > set_bit(addr >> TARGET_PAGE_BITS, ram_list.dirty_memory[client]); > } > > +static inline void cpu_physical_memory_set_dirty_range_nocode(ram_addr_t start, > + ram_addr_t length) > +{ > + unsigned long end, page; > + > + end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS; > + page = start >> TARGET_PAGE_BITS; > + bitmap_set(ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION], page, end - page); > + bitmap_set(ram_list.dirty_memory[DIRTY_MEMORY_VGA], page, end - page); > +} > + > static inline void cpu_physical_memory_set_dirty_range(ram_addr_t start, > ram_addr_t length) > { > -- > 1.8.3.1
On Mo, 2014-07-21 at 17:06 +0200, Paolo Bonzini wrote: > Devices that use address_space_rw to write large areas to memory > (as opposed to address_space_map/unmap) were broken with respect > to migration since fe680d0 (exec: Limit translation limiting in > address_space_translate to xen, 2014-05-07). Such devices include > IDE CD-ROMs. > > The reason is that invalidate_and_set_dirty (called by address_space_rw > but not address_space_map/unmap) was only setting the dirty bit for > the first page in the translation. > > To fix this, introduce cpu_physical_memory_set_dirty_range_nocode that > is the same as cpu_physical_memory_set_dirty_range except it does not > muck with the DIRTY_MEMORY_CODE bitmap. This function can be used if > the caller invalidates translations with tb_invalidate_phys_page_range. > > There is another difference between cpu_physical_memory_set_dirty_range > and cpu_physical_memory_set_dirty_flag; the former includes a call > to xen_modified_memory. This is handled separately in > invalidate_and_set_dirty, and is not needed in other callers of > cpu_physical_memory_set_dirty_range_nocode, so leave it alone. > > Just one nit: now that invalidate_and_set_dirty takes care of handling > multiple pages, there is no need for address_space_unmap to wrap it > in a loop. In fact that loop would now be O(n^2). > > Reported-by: Dave Gilbert <dgilbert@redhat.com> > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Tested-by: Gerd Hoffmann <kraxel@redhat.com>
Paolo Bonzini <pbonzini@redhat.com> wrote: > Devices that use address_space_rw to write large areas to memory > (as opposed to address_space_map/unmap) were broken with respect > to migration since fe680d0 (exec: Limit translation limiting in > address_space_translate to xen, 2014-05-07). Such devices include > IDE CD-ROMs. > > The reason is that invalidate_and_set_dirty (called by address_space_rw > but not address_space_map/unmap) was only setting the dirty bit for > the first page in the translation. > > To fix this, introduce cpu_physical_memory_set_dirty_range_nocode that > is the same as cpu_physical_memory_set_dirty_range except it does not > muck with the DIRTY_MEMORY_CODE bitmap. This function can be used if > the caller invalidates translations with tb_invalidate_phys_page_range. > > There is another difference between cpu_physical_memory_set_dirty_range > and cpu_physical_memory_set_dirty_flag; the former includes a call > to xen_modified_memory. This is handled separately in > invalidate_and_set_dirty, and is not needed in other callers of > cpu_physical_memory_set_dirty_range_nocode, so leave it alone. > > Just one nit: now that invalidate_and_set_dirty takes care of handling > multiple pages, there is no need for address_space_unmap to wrap it > in a loop. In fact that loop would now be O(n^2). > > Reported-by: Dave Gilbert <dgilbert@redhat.com> > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Paolo, are you doing the pull for this, or should I do it? Thanks, Juan.
diff --git a/exec.c b/exec.c index 5a2a25e..765bd94 100644 --- a/exec.c +++ b/exec.c @@ -1568,8 +1568,7 @@ static void notdirty_mem_write(void *opaque, hwaddr ram_addr, default: abort(); } - cpu_physical_memory_set_dirty_flag(ram_addr, DIRTY_MEMORY_MIGRATION); - cpu_physical_memory_set_dirty_flag(ram_addr, DIRTY_MEMORY_VGA); + cpu_physical_memory_set_dirty_range_nocode(ram_addr, size); /* we remove the notdirty callback only if the code has been flushed */ if (!cpu_physical_memory_is_clean(ram_addr)) { @@ -1978,8 +1977,7 @@ static void invalidate_and_set_dirty(hwaddr addr, /* invalidate code */ tb_invalidate_phys_page_range(addr, addr + length, 0); /* set dirty bit */ - cpu_physical_memory_set_dirty_flag(addr, DIRTY_MEMORY_VGA); - cpu_physical_memory_set_dirty_flag(addr, DIRTY_MEMORY_MIGRATION); + cpu_physical_memory_set_dirty_range_nocode(addr, length); } xen_modified_memory(addr, length); } @@ -2335,15 +2333,7 @@ void address_space_unmap(AddressSpace *as, void *buffer, hwaddr len, mr = qemu_ram_addr_from_host(buffer, &addr1); assert(mr != NULL); if (is_write) { - while (access_len) { - unsigned l; - l = TARGET_PAGE_SIZE; - if (l > access_len) - l = access_len; - invalidate_and_set_dirty(addr1, l); - addr1 += l; - access_len -= l; - } + invalidate_and_set_dirty(addr1, access_len); } if (xen_enabled()) { xen_invalidate_map_cache_entry(buffer); @@ -2581,9 +2571,7 @@ void stl_phys_notdirty(AddressSpace *as, hwaddr addr, uint32_t val) /* invalidate code */ tb_invalidate_phys_page_range(addr1, addr1 + 4, 0); /* set dirty bit */ - cpu_physical_memory_set_dirty_flag(addr1, - DIRTY_MEMORY_MIGRATION); - cpu_physical_memory_set_dirty_flag(addr1, DIRTY_MEMORY_VGA); + cpu_physical_memory_set_dirty_range_nocode(addr1, 4); } } } diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h index e9eb831..6593be1 100644 --- a/include/exec/ram_addr.h +++ b/include/exec/ram_addr.h @@ -71,6 +71,17 @@ static inline void cpu_physical_memory_set_dirty_flag(ram_addr_t addr, set_bit(addr >> TARGET_PAGE_BITS, ram_list.dirty_memory[client]); } +static inline void cpu_physical_memory_set_dirty_range_nocode(ram_addr_t start, + ram_addr_t length) +{ + unsigned long end, page; + + end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS; + page = start >> TARGET_PAGE_BITS; + bitmap_set(ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION], page, end - page); + bitmap_set(ram_list.dirty_memory[DIRTY_MEMORY_VGA], page, end - page); +} + static inline void cpu_physical_memory_set_dirty_range(ram_addr_t start, ram_addr_t length) {
Devices that use address_space_rw to write large areas to memory (as opposed to address_space_map/unmap) were broken with respect to migration since fe680d0 (exec: Limit translation limiting in address_space_translate to xen, 2014-05-07). Such devices include IDE CD-ROMs. The reason is that invalidate_and_set_dirty (called by address_space_rw but not address_space_map/unmap) was only setting the dirty bit for the first page in the translation. To fix this, introduce cpu_physical_memory_set_dirty_range_nocode that is the same as cpu_physical_memory_set_dirty_range except it does not muck with the DIRTY_MEMORY_CODE bitmap. This function can be used if the caller invalidates translations with tb_invalidate_phys_page_range. There is another difference between cpu_physical_memory_set_dirty_range and cpu_physical_memory_set_dirty_flag; the former includes a call to xen_modified_memory. This is handled separately in invalidate_and_set_dirty, and is not needed in other callers of cpu_physical_memory_set_dirty_range_nocode, so leave it alone. Just one nit: now that invalidate_and_set_dirty takes care of handling multiple pages, there is no need for address_space_unmap to wrap it in a loop. In fact that loop would now be O(n^2). Reported-by: Dave Gilbert <dgilbert@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> --- exec.c | 20 ++++---------------- include/exec/ram_addr.h | 11 +++++++++++ 2 files changed, 15 insertions(+), 16 deletions(-)