From e660f3651e349f658fe393917bab3ef8da44448c Mon Sep 17 00:00:00 2001
From: Laszlo Ersek <lersek@redhat.com>
Date: Fri, 7 Nov 2014 17:18:10 +0100
Subject: [PATCH 23/41] dump: eliminate DumpState.page_size ("guest's page
size")
Message-id: <1415380693-16593-24-git-send-email-lersek@redhat.com>
Patchwork-id: 62211
O-Subject: [RHEL-7.1 qemu-kvm PATCH 23/26] dump: eliminate DumpState.page_size ("guest's page size")
Bugzilla: 1157798
RH-Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
RH-Acked-by: Luiz Capitulino <lcapitulino@redhat.com>
RH-Acked-by: dgibson <dgibson@redhat.com>
Use TARGET_PAGE_SIZE and ~TARGET_PAGE_MASK instead.
"DumpState.page_size" has type "size_t", whereas TARGET_PAGE_SIZE has type
"int". TARGET_PAGE_MASK is of type "int" and has negative value. The patch
affects the implicit type conversions as follows:
- create_header32() and create_header64(): assigned to "block_size", which
has type "uint32_t". No change.
- get_next_page(): "block->target_start", "block->target_end" and "addr"
have type "hwaddr" (uint64_t).
Before the patch,
- if "size_t" was "uint64_t", then no additional conversion was done as
part of the usual arithmetic conversions,
- If "size_t" was "uint32_t", then it was widened to uint64_t as part of
the usual arithmetic conversions,
for the remainder and addition operators.
After the patch,
- "~TARGET_PAGE_MASK" expands to ~~((1 << TARGET_PAGE_BITS) - 1). It
has type "int" and positive value (only least significant bits set).
That's converted (widened) to "uint64_t" for the bit-ands. No visible
change.
- The same holds for the (addr + TARGET_PAGE_SIZE) addition.
- write_dump_pages():
- TARGET_PAGE_SIZE passed as argument to a bunch of functions that all
have prototypes. No change.
- When incrementing "offset_data" (of type "off_t"): given that we never
build for ILP32_OFF32 (see "-D_FILE_OFFSET_BITS=64" in configure),
"off_t" is always "int64_t", and we only need to consider:
- ILP32_OFFBIG: "size_t" is "uint32_t".
- before: int64_t += uint32_t. Page size converted to int64_t for
the addition.
- after: int64_t += int32_t. No change.
- LP64_OFF64: "size_t" is "uint64_t".
- before: int64_t += uint64_t. Offset converted to uint64_t for the
addition, then the uint64_t result is converted to int64_t for
storage.
- after: int64_t += int32_t. Same as the ILP32_OFFBIG/after case.
No visible change.
- (size_out < s->page_size) comparisons, and (size_out = s->page_size)
assignment:
- before: "size_out" is of type "size_t", no implicit conversion for
either operator.
- after: TARGET_PAGE_SIZE (of type "int" and positive value) is
converted to "size_t" (for the relop because the latter is
one of "uint32_t" and "uint64_t"). No visible change.
- dump_init():
- DIV_ROUND_UP(DIV_ROUND_UP(s->max_mapnr, CHAR_BIT), s->page_size): The
innermost "DumpState.max_mapnr" field has type uint64_t, which
propagates through all implicit conversions at hand:
#define DIV_ROUND_UP(n,d) (((n) + (d) - 1) / (d))
regardless of the page size macro argument's type. In the outer macro
replacement, the page size is converted from uint32_t and int32_t
alike to uint64_t.
- (tmp * s->page_size) multiplication: "tmp" has size "uint64_t"; the
RHS is converted to that type from uint32_t and int32_t just the same
if it's not uint64_t to begin with.
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
(cherry picked from commit 2f859f80c2077e00237ea1dfae2523ebd8377f5f)
Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>
---
dump.c | 51 +++++++++++++++++++++++++--------------------------
1 file changed, 25 insertions(+), 26 deletions(-)
diff --git a/dump.c b/dump.c
index bc82b55..f8e0fd7 100644
--- a/dump.c
+++ b/dump.c
@@ -90,7 +90,6 @@ typedef struct DumpState {
uint8_t *note_buf; /* buffer for notes */
size_t note_buf_offset; /* the writing place in note_buf */
uint32_t nr_cpus; /* number of guest's cpu */
- size_t page_size; /* guest's page size */
uint64_t max_mapnr; /* the biggest guest's phys-mem's number */
size_t len_dump_bitmap; /* the size of the place used to store
dump_bitmap in vmcore */
@@ -811,7 +810,7 @@ static int create_header32(DumpState *s)
strncpy(dh->signature, KDUMP_SIGNATURE, strlen(KDUMP_SIGNATURE));
dh->header_version = cpu_convert_to_target32(6, endian);
- block_size = s->page_size;
+ block_size = TARGET_PAGE_SIZE;
dh->block_size = cpu_convert_to_target32(block_size, endian);
sub_hdr_size = sizeof(struct KdumpSubHeader32) + s->note_size;
sub_hdr_size = DIV_ROUND_UP(sub_hdr_size, block_size);
@@ -918,7 +917,7 @@ static int create_header64(DumpState *s)
strncpy(dh->signature, KDUMP_SIGNATURE, strlen(KDUMP_SIGNATURE));
dh->header_version = cpu_convert_to_target32(6, endian);
- block_size = s->page_size;
+ block_size = TARGET_PAGE_SIZE;
dh->block_size = cpu_convert_to_target32(block_size, endian);
sub_hdr_size = sizeof(struct KdumpSubHeader64) + s->note_size;
sub_hdr_size = DIV_ROUND_UP(sub_hdr_size, block_size);
@@ -1089,8 +1088,8 @@ static bool get_next_page(GuestPhysBlock **blockptr, uint64_t *pfnptr,
if (!block) {
block = QTAILQ_FIRST(&s->guest_phys_blocks.head);
*blockptr = block;
- assert(block->target_start % s->page_size == 0);
- assert(block->target_end % s->page_size == 0);
+ assert((block->target_start & ~TARGET_PAGE_MASK) == 0);
+ assert((block->target_end & ~TARGET_PAGE_MASK) == 0);
*pfnptr = paddr_to_pfn(block->target_start);
if (bufptr) {
*bufptr = block->host_addr;
@@ -1102,7 +1101,7 @@ static bool get_next_page(GuestPhysBlock **blockptr, uint64_t *pfnptr,
addr = pfn_to_paddr(*pfnptr);
if ((addr >= block->target_start) &&
- (addr + s->page_size <= block->target_end)) {
+ (addr + TARGET_PAGE_SIZE <= block->target_end)) {
buf = block->host_addr + (addr - block->target_start);
} else {
/* the next page is in the next block */
@@ -1111,8 +1110,8 @@ static bool get_next_page(GuestPhysBlock **blockptr, uint64_t *pfnptr,
if (!block) {
return false;
}
- assert(block->target_start % s->page_size == 0);
- assert(block->target_end % s->page_size == 0);
+ assert((block->target_start & ~TARGET_PAGE_MASK) == 0);
+ assert((block->target_end & ~TARGET_PAGE_MASK) == 0);
*pfnptr = paddr_to_pfn(block->target_start);
buf = block->host_addr;
}
@@ -1297,7 +1296,7 @@ static int write_dump_pages(DumpState *s)
prepare_data_cache(&page_data, s, offset_data);
/* prepare buffer to store compressed data */
- len_buf_out = get_len_buf_out(s->page_size, s->flag_compress);
+ len_buf_out = get_len_buf_out(TARGET_PAGE_SIZE, s->flag_compress);
if (len_buf_out == 0) {
dump_error(s, "dump: failed to get length of output buffer.\n");
goto out;
@@ -1313,19 +1312,19 @@ static int write_dump_pages(DumpState *s)
* init zero page's page_desc and page_data, because every zero page
* uses the same page_data
*/
- pd_zero.size = cpu_convert_to_target32(s->page_size, endian);
+ pd_zero.size = cpu_convert_to_target32(TARGET_PAGE_SIZE, endian);
pd_zero.flags = cpu_convert_to_target32(0, endian);
pd_zero.offset = cpu_convert_to_target64(offset_data, endian);
pd_zero.page_flags = cpu_convert_to_target64(0, endian);
- buf = g_malloc0(s->page_size);
- ret = write_cache(&page_data, buf, s->page_size, false);
+ buf = g_malloc0(TARGET_PAGE_SIZE);
+ ret = write_cache(&page_data, buf, TARGET_PAGE_SIZE, false);
g_free(buf);
if (ret < 0) {
dump_error(s, "dump: failed to write page data(zero page).\n");
goto out;
}
- offset_data += s->page_size;
+ offset_data += TARGET_PAGE_SIZE;
/*
* dump memory to vmcore page by page. zero page will all be resided in the
@@ -1333,7 +1332,7 @@ static int write_dump_pages(DumpState *s)
*/
while (get_next_page(&block_iter, &pfn_iter, &buf, s)) {
/* check zero page */
- if (is_zero_page(buf, s->page_size)) {
+ if (is_zero_page(buf, TARGET_PAGE_SIZE)) {
ret = write_cache(&page_desc, &pd_zero, sizeof(PageDescriptor),
false);
if (ret < 0) {
@@ -1354,8 +1353,9 @@ static int write_dump_pages(DumpState *s)
*/
size_out = len_buf_out;
if ((s->flag_compress & DUMP_DH_COMPRESSED_ZLIB) &&
- (compress2(buf_out, (uLongf *)&size_out, buf, s->page_size,
- Z_BEST_SPEED) == Z_OK) && (size_out < s->page_size)) {
+ (compress2(buf_out, (uLongf *)&size_out, buf,
+ TARGET_PAGE_SIZE, Z_BEST_SPEED) == Z_OK) &&
+ (size_out < TARGET_PAGE_SIZE)) {
pd.flags = cpu_convert_to_target32(DUMP_DH_COMPRESSED_ZLIB,
endian);
pd.size = cpu_convert_to_target32(size_out, endian);
@@ -1367,9 +1367,9 @@ static int write_dump_pages(DumpState *s)
}
#ifdef CONFIG_LZO
} else if ((s->flag_compress & DUMP_DH_COMPRESSED_LZO) &&
- (lzo1x_1_compress(buf, s->page_size, buf_out,
+ (lzo1x_1_compress(buf, TARGET_PAGE_SIZE, buf_out,
(lzo_uint *)&size_out, wrkmem) == LZO_E_OK) &&
- (size_out < s->page_size)) {
+ (size_out < TARGET_PAGE_SIZE)) {
pd.flags = cpu_convert_to_target32(DUMP_DH_COMPRESSED_LZO,
endian);
pd.size = cpu_convert_to_target32(size_out, endian);
@@ -1382,9 +1382,9 @@ static int write_dump_pages(DumpState *s)
#endif
#ifdef CONFIG_SNAPPY
} else if ((s->flag_compress & DUMP_DH_COMPRESSED_SNAPPY) &&
- (snappy_compress((char *)buf, s->page_size,
+ (snappy_compress((char *)buf, TARGET_PAGE_SIZE,
(char *)buf_out, &size_out) == SNAPPY_OK) &&
- (size_out < s->page_size)) {
+ (size_out < TARGET_PAGE_SIZE)) {
pd.flags = cpu_convert_to_target32(
DUMP_DH_COMPRESSED_SNAPPY, endian);
pd.size = cpu_convert_to_target32(size_out, endian);
@@ -1398,13 +1398,13 @@ static int write_dump_pages(DumpState *s)
} else {
/*
* fall back to save in plaintext, size_out should be
- * assigned to s->page_size
+ * assigned TARGET_PAGE_SIZE
*/
pd.flags = cpu_convert_to_target32(0, endian);
- size_out = s->page_size;
+ size_out = TARGET_PAGE_SIZE;
pd.size = cpu_convert_to_target32(size_out, endian);
- ret = write_cache(&page_data, buf, s->page_size, false);
+ ret = write_cache(&page_data, buf, TARGET_PAGE_SIZE, false);
if (ret < 0) {
dump_error(s, "dump: failed to write page data.\n");
goto out;
@@ -1616,13 +1616,12 @@ static int dump_init(DumpState *s, int fd, bool has_format,
}
s->nr_cpus = nr_cpus;
- s->page_size = TARGET_PAGE_SIZE;
get_max_mapnr(s);
uint64_t tmp;
- tmp = DIV_ROUND_UP(DIV_ROUND_UP(s->max_mapnr, CHAR_BIT), s->page_size);
- s->len_dump_bitmap = tmp * s->page_size;
+ tmp = DIV_ROUND_UP(DIV_ROUND_UP(s->max_mapnr, CHAR_BIT), TARGET_PAGE_SIZE);
+ s->len_dump_bitmap = tmp * TARGET_PAGE_SIZE;
/* init for kdump-compressed format */
if (has_format && format != DUMP_GUEST_MEMORY_FORMAT_ELF) {
--
1.8.3.1