| Message ID | 20240102015808.132373-9-richard.henderson@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | linux-user: Improve host and guest page size handling | expand |
On 1/2/24 05:57, Richard Henderson wrote: > Use qemu_real_host_page_size instead. > > Signed-off-by: Richard Henderson <richard.henderson@linaro.org> > --- > linux-user/mmap.c | 66 +++++++++++++++++++++++------------------------ > 1 file changed, 33 insertions(+), 33 deletions(-) > > diff --git a/linux-user/mmap.c b/linux-user/mmap.c > index 96c9433e27..4d3c8717b9 100644 > --- a/linux-user/mmap.c > +++ b/linux-user/mmap.c > @@ -165,6 +165,7 @@ static int target_to_host_prot(int prot) > /* NOTE: all the constants are the HOST ones, but addresses are target. */ > int target_mprotect(abi_ulong start, abi_ulong len, int target_prot) > { > + int host_page_size = qemu_real_host_page_size(); > abi_ulong starts[3]; > abi_ulong lens[3]; > int prots[3]; > @@ -189,13 +190,13 @@ int target_mprotect(abi_ulong start, abi_ulong len, int target_prot) > } > > last = start + len - 1; > - host_start = start & qemu_host_page_mask; > + host_start = start & -host_page_size; > host_last = HOST_PAGE_ALIGN(last) - 1; > nranges = 0; > > mmap_lock(); > > - if (host_last - host_start < qemu_host_page_size) { > + if (host_last - host_start < host_page_size) { > /* Single host page contains all guest pages: sum the prot. */ > prot1 = target_prot; > for (abi_ulong a = host_start; a < start; a += TARGET_PAGE_SIZE) { > @@ -205,7 +206,7 @@ int target_mprotect(abi_ulong start, abi_ulong len, int target_prot) > prot1 |= page_get_flags(a + 1); > } > starts[nranges] = host_start; > - lens[nranges] = qemu_host_page_size; > + lens[nranges] = host_page_size; > prots[nranges] = prot1; > nranges++; > } else { > @@ -218,10 +219,10 @@ int target_mprotect(abi_ulong start, abi_ulong len, int target_prot) > /* If the resulting sum differs, create a new range. */ > if (prot1 != target_prot) { > starts[nranges] = host_start; > - lens[nranges] = qemu_host_page_size; > + lens[nranges] = host_page_size; > prots[nranges] = prot1; > nranges++; > - host_start += qemu_host_page_size; > + host_start += host_page_size; > } > } > > @@ -233,9 +234,9 @@ int target_mprotect(abi_ulong start, abi_ulong len, int target_prot) > } > /* If the resulting sum differs, create a new range. */ > if (prot1 != target_prot) { > - host_last -= qemu_host_page_size; > + host_last -= host_page_size; > starts[nranges] = host_last + 1; > - lens[nranges] = qemu_host_page_size; > + lens[nranges] = host_page_size; > prots[nranges] = prot1; > nranges++; > } > @@ -270,6 +271,7 @@ int target_mprotect(abi_ulong start, abi_ulong len, int target_prot) > static bool mmap_frag(abi_ulong real_start, abi_ulong start, abi_ulong last, > int prot, int flags, int fd, off_t offset) > { > + int host_page_size = qemu_real_host_page_size(); > abi_ulong real_last; > void *host_start; > int prot_old, prot_new; > @@ -286,7 +288,7 @@ static bool mmap_frag(abi_ulong real_start, abi_ulong start, abi_ulong last, > return false; > } > > - real_last = real_start + qemu_host_page_size - 1; > + real_last = real_start + host_page_size - 1; > host_start = g2h_untagged(real_start); > > /* Get the protection of the target pages outside the mapping. */ > @@ -304,12 +306,12 @@ static bool mmap_frag(abi_ulong real_start, abi_ulong start, abi_ulong last, > * outside of the fragment we need to map. Allocate a new host > * page to cover, discarding whatever else may have been present. > */ > - void *p = mmap(host_start, qemu_host_page_size, > + void *p = mmap(host_start, host_page_size, > target_to_host_prot(prot), > flags | MAP_ANONYMOUS, -1, 0); > if (p != host_start) { > if (p != MAP_FAILED) { > - munmap(p, qemu_host_page_size); > + munmap(p, host_page_size); > errno = EEXIST; > } > return false; > @@ -324,7 +326,7 @@ static bool mmap_frag(abi_ulong real_start, abi_ulong start, abi_ulong last, > /* Adjust protection to be able to write. */ > if (!(host_prot_old & PROT_WRITE)) { > host_prot_old |= PROT_WRITE; > - mprotect(host_start, qemu_host_page_size, host_prot_old); > + mprotect(host_start, host_page_size, host_prot_old); > } > > /* Read or zero the new guest pages. */ > @@ -338,7 +340,7 @@ static bool mmap_frag(abi_ulong real_start, abi_ulong start, abi_ulong last, > > /* Put final protection */ > if (host_prot_new != host_prot_old) { > - mprotect(host_start, qemu_host_page_size, host_prot_new); > + mprotect(host_start, host_page_size, host_prot_new); > } > return true; > } > @@ -373,17 +375,18 @@ static abi_ulong mmap_find_vma_reserved(abi_ulong start, abi_ulong size, > */ > abi_ulong mmap_find_vma(abi_ulong start, abi_ulong size, abi_ulong align) > { > + int host_page_size = qemu_real_host_page_size(); > void *ptr, *prev; > abi_ulong addr; > int wrapped, repeat; > > - align = MAX(align, qemu_host_page_size); > + align = MAX(align, host_page_size); > > /* If 'start' == 0, then a default start address is used. */ > if (start == 0) { > start = mmap_next_start; > } else { > - start &= qemu_host_page_mask; > + start &= -host_page_size; > } > start = ROUND_UP(start, align); > > @@ -492,6 +495,7 @@ abi_ulong mmap_find_vma(abi_ulong start, abi_ulong size, abi_ulong align) > abi_long target_mmap(abi_ulong start, abi_ulong len, int target_prot, > int flags, int fd, off_t offset) > { > + int host_page_size = qemu_real_host_page_size(); > abi_ulong ret, last, real_start, real_last, retaddr, host_len; > abi_ulong passthrough_start = -1, passthrough_last = 0; > int page_flags; > @@ -537,8 +541,8 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, int target_prot, > } > } > > - real_start = start & qemu_host_page_mask; > - host_offset = offset & qemu_host_page_mask; > + real_start = start & -host_page_size; > + host_offset = offset & -host_page_size; > > /* > * If the user is asking for the kernel to find a location, do that > @@ -567,8 +571,7 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, int target_prot, > * may need to truncate file maps at EOF and add extra anonymous pages > * up to the targets page boundary. > */ > - if ((qemu_real_host_page_size() < qemu_host_page_size) && > - !(flags & MAP_ANONYMOUS)) { > + if (host_page_size < TARGET_PAGE_SIZE && !(flags & MAP_ANONYMOUS)) { > struct stat sb; > > if (fstat(fd, &sb) == -1) { > @@ -595,11 +598,7 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, int target_prot, > host_len = HOST_PAGE_ALIGN(host_len); > host_prot = target_to_host_prot(target_prot); > > - /* > - * Note: we prefer to control the mapping address. It is > - * especially important if qemu_host_page_size > > - * qemu_real_host_page_size. > - */ > + /* Note: we prefer to control the mapping address. */ > p = mmap(g2h_untagged(start), host_len, host_prot, > flags | MAP_FIXED | MAP_ANONYMOUS, -1, 0); > if (p == MAP_FAILED) { > @@ -665,7 +664,7 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, int target_prot, > * aligned, so we read it > */ > if (!(flags & MAP_ANONYMOUS) && > - (offset & ~qemu_host_page_mask) != (start & ~qemu_host_page_mask)) { > + (offset & (host_page_size - 1)) != (start & (host_page_size - 1))) { > /* > * msync() won't work here, so we return an error if write is > * possible while it is a shared mapping > @@ -694,7 +693,7 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, int target_prot, > > /* handle the start of the mapping */ > if (start > real_start) { > - if (real_last == real_start + qemu_host_page_size - 1) { > + if (real_last == real_start + host_page_size - 1) { > /* one single host page */ > if (!mmap_frag(real_start, start, last, > target_prot, flags, fd, offset)) { > @@ -703,21 +702,21 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, int target_prot, > goto the_end1; > } > if (!mmap_frag(real_start, start, > - real_start + qemu_host_page_size - 1, > + real_start + host_page_size - 1, > target_prot, flags, fd, offset)) { > goto fail; > } > - real_start += qemu_host_page_size; > + real_start += host_page_size; > } > /* handle the end of the mapping */ > if (last < real_last) { > - abi_ulong real_page = real_last - qemu_host_page_size + 1; > + abi_ulong real_page = real_last - host_page_size + 1; > if (!mmap_frag(real_page, real_page, last, > target_prot, flags, fd, > offset + real_page - start)) { > goto fail; > } > - real_last -= qemu_host_page_size; > + real_last -= host_page_size; > } > > /* map the middle (easier) */ > @@ -784,6 +783,7 @@ fail: > > static int mmap_reserve_or_unmap(abi_ulong start, abi_ulong len) > { > + int host_page_size = qemu_real_host_page_size(); > abi_ulong real_start; > abi_ulong real_last; > abi_ulong real_len; > @@ -793,7 +793,7 @@ static int mmap_reserve_or_unmap(abi_ulong start, abi_ulong len) > int prot; > > last = start + len - 1; > - real_start = start & qemu_host_page_mask; > + real_start = start & -host_page_size; > real_last = HOST_PAGE_ALIGN(last) - 1; > > /* > @@ -802,7 +802,7 @@ static int mmap_reserve_or_unmap(abi_ulong start, abi_ulong len) > * The single page special case is required for the last page, > * lest real_start overflow to zero. > */ > - if (real_last - real_start < qemu_host_page_size) { > + if (real_last - real_start < host_page_size) { > prot = 0; > for (a = real_start; a < start; a += TARGET_PAGE_SIZE) { > prot |= page_get_flags(a); > @@ -818,14 +818,14 @@ static int mmap_reserve_or_unmap(abi_ulong start, abi_ulong len) > prot |= page_get_flags(a); > } > if (prot != 0) { > - real_start += qemu_host_page_size; > + real_start += host_page_size; > } > > for (prot = 0, a = last; a < real_last; a += TARGET_PAGE_SIZE) { > prot |= page_get_flags(a + 1); > } > if (prot != 0) { > - real_last -= qemu_host_page_size; > + real_last -= host_page_size; > } > > if (real_last < real_start) { For me, the transformation ~page_mask == page_size - 1 and page_mask == -page_size was not so intuitive, until I tried it on paper. Could it be useful to have macros PAGE_BITS(page_size), and PAGE_MASK(page_size) for this?. All would be defined from page_sz, so there is no duplicated data, and it would avoid a subtle error when forgetting an operator, while helping to read the code. Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
On 8/1/24 10:47, Pierrick Bouvier wrote: > On 1/2/24 05:57, Richard Henderson wrote: >> Use qemu_real_host_page_size instead. >> >> Signed-off-by: Richard Henderson <richard.henderson@linaro.org> >> --- >> linux-user/mmap.c | 66 +++++++++++++++++++++++------------------------ >> 1 file changed, 33 insertions(+), 33 deletions(-) >> >> diff --git a/linux-user/mmap.c b/linux-user/mmap.c >> index 96c9433e27..4d3c8717b9 100644 >> --- a/linux-user/mmap.c >> +++ b/linux-user/mmap.c >> @@ -165,6 +165,7 @@ static int target_to_host_prot(int prot) >> /* NOTE: all the constants are the HOST ones, but addresses are >> target. */ >> int target_mprotect(abi_ulong start, abi_ulong len, int target_prot) >> { >> + int host_page_size = qemu_real_host_page_size(); >> abi_ulong starts[3]; >> abi_ulong lens[3]; >> int prots[3]; >> @@ -189,13 +190,13 @@ int target_mprotect(abi_ulong start, abi_ulong >> len, int target_prot) >> } >> last = start + len - 1; >> - host_start = start & qemu_host_page_mask; >> + host_start = start & -host_page_size; >> host_last = HOST_PAGE_ALIGN(last) - 1; >> nranges = 0; >> mmap_lock(); >> - if (host_last - host_start < qemu_host_page_size) { >> + if (host_last - host_start < host_page_size) { >> /* Single host page contains all guest pages: sum the prot. */ >> prot1 = target_prot; >> for (abi_ulong a = host_start; a < start; a += >> TARGET_PAGE_SIZE) { >> @@ -205,7 +206,7 @@ int target_mprotect(abi_ulong start, abi_ulong >> len, int target_prot) >> prot1 |= page_get_flags(a + 1); >> } >> starts[nranges] = host_start; >> - lens[nranges] = qemu_host_page_size; >> + lens[nranges] = host_page_size; >> prots[nranges] = prot1; >> nranges++; >> } else { >> @@ -218,10 +219,10 @@ int target_mprotect(abi_ulong start, abi_ulong >> len, int target_prot) >> /* If the resulting sum differs, create a new range. */ >> if (prot1 != target_prot) { >> starts[nranges] = host_start; >> - lens[nranges] = qemu_host_page_size; >> + lens[nranges] = host_page_size; >> prots[nranges] = prot1; >> nranges++; >> - host_start += qemu_host_page_size; >> + host_start += host_page_size; >> } >> } >> @@ -233,9 +234,9 @@ int target_mprotect(abi_ulong start, abi_ulong >> len, int target_prot) >> } >> /* If the resulting sum differs, create a new range. */ >> if (prot1 != target_prot) { >> - host_last -= qemu_host_page_size; >> + host_last -= host_page_size; >> starts[nranges] = host_last + 1; >> - lens[nranges] = qemu_host_page_size; >> + lens[nranges] = host_page_size; >> prots[nranges] = prot1; >> nranges++; >> } >> @@ -270,6 +271,7 @@ int target_mprotect(abi_ulong start, abi_ulong >> len, int target_prot) >> static bool mmap_frag(abi_ulong real_start, abi_ulong start, >> abi_ulong last, >> int prot, int flags, int fd, off_t offset) >> { >> + int host_page_size = qemu_real_host_page_size(); >> abi_ulong real_last; >> void *host_start; >> int prot_old, prot_new; >> @@ -286,7 +288,7 @@ static bool mmap_frag(abi_ulong real_start, >> abi_ulong start, abi_ulong last, >> return false; >> } >> - real_last = real_start + qemu_host_page_size - 1; >> + real_last = real_start + host_page_size - 1; >> host_start = g2h_untagged(real_start); >> /* Get the protection of the target pages outside the mapping. */ >> @@ -304,12 +306,12 @@ static bool mmap_frag(abi_ulong real_start, >> abi_ulong start, abi_ulong last, >> * outside of the fragment we need to map. Allocate a new host >> * page to cover, discarding whatever else may have been >> present. >> */ >> - void *p = mmap(host_start, qemu_host_page_size, >> + void *p = mmap(host_start, host_page_size, >> target_to_host_prot(prot), >> flags | MAP_ANONYMOUS, -1, 0); >> if (p != host_start) { >> if (p != MAP_FAILED) { >> - munmap(p, qemu_host_page_size); >> + munmap(p, host_page_size); >> errno = EEXIST; >> } >> return false; >> @@ -324,7 +326,7 @@ static bool mmap_frag(abi_ulong real_start, >> abi_ulong start, abi_ulong last, >> /* Adjust protection to be able to write. */ >> if (!(host_prot_old & PROT_WRITE)) { >> host_prot_old |= PROT_WRITE; >> - mprotect(host_start, qemu_host_page_size, host_prot_old); >> + mprotect(host_start, host_page_size, host_prot_old); >> } >> /* Read or zero the new guest pages. */ >> @@ -338,7 +340,7 @@ static bool mmap_frag(abi_ulong real_start, >> abi_ulong start, abi_ulong last, >> /* Put final protection */ >> if (host_prot_new != host_prot_old) { >> - mprotect(host_start, qemu_host_page_size, host_prot_new); >> + mprotect(host_start, host_page_size, host_prot_new); >> } >> return true; >> } >> @@ -373,17 +375,18 @@ static abi_ulong >> mmap_find_vma_reserved(abi_ulong start, abi_ulong size, >> */ >> abi_ulong mmap_find_vma(abi_ulong start, abi_ulong size, abi_ulong >> align) >> { >> + int host_page_size = qemu_real_host_page_size(); >> void *ptr, *prev; >> abi_ulong addr; >> int wrapped, repeat; >> - align = MAX(align, qemu_host_page_size); >> + align = MAX(align, host_page_size); >> /* If 'start' == 0, then a default start address is used. */ >> if (start == 0) { >> start = mmap_next_start; >> } else { >> - start &= qemu_host_page_mask; >> + start &= -host_page_size; >> } >> start = ROUND_UP(start, align); >> @@ -492,6 +495,7 @@ abi_ulong mmap_find_vma(abi_ulong start, abi_ulong >> size, abi_ulong align) >> abi_long target_mmap(abi_ulong start, abi_ulong len, int target_prot, >> int flags, int fd, off_t offset) >> { >> + int host_page_size = qemu_real_host_page_size(); >> abi_ulong ret, last, real_start, real_last, retaddr, host_len; >> abi_ulong passthrough_start = -1, passthrough_last = 0; >> int page_flags; >> @@ -537,8 +541,8 @@ abi_long target_mmap(abi_ulong start, abi_ulong >> len, int target_prot, >> } >> } >> - real_start = start & qemu_host_page_mask; >> - host_offset = offset & qemu_host_page_mask; >> + real_start = start & -host_page_size; >> + host_offset = offset & -host_page_size; >> /* >> * If the user is asking for the kernel to find a location, do that >> @@ -567,8 +571,7 @@ abi_long target_mmap(abi_ulong start, abi_ulong >> len, int target_prot, >> * may need to truncate file maps at EOF and add extra anonymous >> pages >> * up to the targets page boundary. >> */ >> - if ((qemu_real_host_page_size() < qemu_host_page_size) && >> - !(flags & MAP_ANONYMOUS)) { >> + if (host_page_size < TARGET_PAGE_SIZE && !(flags & MAP_ANONYMOUS)) { >> struct stat sb; >> if (fstat(fd, &sb) == -1) { >> @@ -595,11 +598,7 @@ abi_long target_mmap(abi_ulong start, abi_ulong >> len, int target_prot, >> host_len = HOST_PAGE_ALIGN(host_len); >> host_prot = target_to_host_prot(target_prot); >> - /* >> - * Note: we prefer to control the mapping address. It is >> - * especially important if qemu_host_page_size > >> - * qemu_real_host_page_size. >> - */ >> + /* Note: we prefer to control the mapping address. */ >> p = mmap(g2h_untagged(start), host_len, host_prot, >> flags | MAP_FIXED | MAP_ANONYMOUS, -1, 0); >> if (p == MAP_FAILED) { >> @@ -665,7 +664,7 @@ abi_long target_mmap(abi_ulong start, abi_ulong >> len, int target_prot, >> * aligned, so we read it >> */ >> if (!(flags & MAP_ANONYMOUS) && >> - (offset & ~qemu_host_page_mask) != (start & >> ~qemu_host_page_mask)) { >> + (offset & (host_page_size - 1)) != (start & >> (host_page_size - 1))) { >> /* >> * msync() won't work here, so we return an error if >> write is >> * possible while it is a shared mapping >> @@ -694,7 +693,7 @@ abi_long target_mmap(abi_ulong start, abi_ulong >> len, int target_prot, >> /* handle the start of the mapping */ >> if (start > real_start) { >> - if (real_last == real_start + qemu_host_page_size - 1) { >> + if (real_last == real_start + host_page_size - 1) { >> /* one single host page */ >> if (!mmap_frag(real_start, start, last, >> target_prot, flags, fd, offset)) { >> @@ -703,21 +702,21 @@ abi_long target_mmap(abi_ulong start, abi_ulong >> len, int target_prot, >> goto the_end1; >> } >> if (!mmap_frag(real_start, start, >> - real_start + qemu_host_page_size - 1, >> + real_start + host_page_size - 1, >> target_prot, flags, fd, offset)) { >> goto fail; >> } >> - real_start += qemu_host_page_size; >> + real_start += host_page_size; >> } >> /* handle the end of the mapping */ >> if (last < real_last) { >> - abi_ulong real_page = real_last - qemu_host_page_size + 1; >> + abi_ulong real_page = real_last - host_page_size + 1; >> if (!mmap_frag(real_page, real_page, last, >> target_prot, flags, fd, >> offset + real_page - start)) { >> goto fail; >> } >> - real_last -= qemu_host_page_size; >> + real_last -= host_page_size; >> } >> /* map the middle (easier) */ >> @@ -784,6 +783,7 @@ fail: >> static int mmap_reserve_or_unmap(abi_ulong start, abi_ulong len) >> { >> + int host_page_size = qemu_real_host_page_size(); >> abi_ulong real_start; >> abi_ulong real_last; >> abi_ulong real_len; >> @@ -793,7 +793,7 @@ static int mmap_reserve_or_unmap(abi_ulong start, >> abi_ulong len) >> int prot; >> last = start + len - 1; >> - real_start = start & qemu_host_page_mask; >> + real_start = start & -host_page_size; >> real_last = HOST_PAGE_ALIGN(last) - 1; >> /* >> @@ -802,7 +802,7 @@ static int mmap_reserve_or_unmap(abi_ulong start, >> abi_ulong len) >> * The single page special case is required for the last page, >> * lest real_start overflow to zero. >> */ >> - if (real_last - real_start < qemu_host_page_size) { >> + if (real_last - real_start < host_page_size) { >> prot = 0; >> for (a = real_start; a < start; a += TARGET_PAGE_SIZE) { >> prot |= page_get_flags(a); >> @@ -818,14 +818,14 @@ static int mmap_reserve_or_unmap(abi_ulong >> start, abi_ulong len) >> prot |= page_get_flags(a); >> } >> if (prot != 0) { >> - real_start += qemu_host_page_size; >> + real_start += host_page_size; >> } >> for (prot = 0, a = last; a < real_last; a += >> TARGET_PAGE_SIZE) { >> prot |= page_get_flags(a + 1); >> } >> if (prot != 0) { >> - real_last -= qemu_host_page_size; >> + real_last -= host_page_size; >> } >> if (real_last < real_start) { > > For me, the transformation ~page_mask == page_size - 1 and page_mask == > -page_size was not so intuitive, until I tried it on paper. I have been there ;) Then when you have to deal with code related to pages, this become natural page-related operations. > Could it be useful to have macros PAGE_BITS(page_size), and > PAGE_MASK(page_size) for this?. All would be defined from page_sz, so > there is no duplicated data, and it would avoid a subtle error when > forgetting an operator, while helping to read the code. > > Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org> >
On Tue, Jan 02, 2024 at 12:57:43PM +1100, Richard Henderson wrote: > Use qemu_real_host_page_size instead. > > Signed-off-by: Richard Henderson <richard.henderson@linaro.org> > --- > linux-user/mmap.c | 66 +++++++++++++++++++++++------------------------ > 1 file changed, 33 insertions(+), 33 deletions(-) Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
diff --git a/linux-user/mmap.c b/linux-user/mmap.c index 96c9433e27..4d3c8717b9 100644 --- a/linux-user/mmap.c +++ b/linux-user/mmap.c @@ -165,6 +165,7 @@ static int target_to_host_prot(int prot) /* NOTE: all the constants are the HOST ones, but addresses are target. */ int target_mprotect(abi_ulong start, abi_ulong len, int target_prot) { + int host_page_size = qemu_real_host_page_size(); abi_ulong starts[3]; abi_ulong lens[3]; int prots[3]; @@ -189,13 +190,13 @@ int target_mprotect(abi_ulong start, abi_ulong len, int target_prot) } last = start + len - 1; - host_start = start & qemu_host_page_mask; + host_start = start & -host_page_size; host_last = HOST_PAGE_ALIGN(last) - 1; nranges = 0; mmap_lock(); - if (host_last - host_start < qemu_host_page_size) { + if (host_last - host_start < host_page_size) { /* Single host page contains all guest pages: sum the prot. */ prot1 = target_prot; for (abi_ulong a = host_start; a < start; a += TARGET_PAGE_SIZE) { @@ -205,7 +206,7 @@ int target_mprotect(abi_ulong start, abi_ulong len, int target_prot) prot1 |= page_get_flags(a + 1); } starts[nranges] = host_start; - lens[nranges] = qemu_host_page_size; + lens[nranges] = host_page_size; prots[nranges] = prot1; nranges++; } else { @@ -218,10 +219,10 @@ int target_mprotect(abi_ulong start, abi_ulong len, int target_prot) /* If the resulting sum differs, create a new range. */ if (prot1 != target_prot) { starts[nranges] = host_start; - lens[nranges] = qemu_host_page_size; + lens[nranges] = host_page_size; prots[nranges] = prot1; nranges++; - host_start += qemu_host_page_size; + host_start += host_page_size; } } @@ -233,9 +234,9 @@ int target_mprotect(abi_ulong start, abi_ulong len, int target_prot) } /* If the resulting sum differs, create a new range. */ if (prot1 != target_prot) { - host_last -= qemu_host_page_size; + host_last -= host_page_size; starts[nranges] = host_last + 1; - lens[nranges] = qemu_host_page_size; + lens[nranges] = host_page_size; prots[nranges] = prot1; nranges++; } @@ -270,6 +271,7 @@ int target_mprotect(abi_ulong start, abi_ulong len, int target_prot) static bool mmap_frag(abi_ulong real_start, abi_ulong start, abi_ulong last, int prot, int flags, int fd, off_t offset) { + int host_page_size = qemu_real_host_page_size(); abi_ulong real_last; void *host_start; int prot_old, prot_new; @@ -286,7 +288,7 @@ static bool mmap_frag(abi_ulong real_start, abi_ulong start, abi_ulong last, return false; } - real_last = real_start + qemu_host_page_size - 1; + real_last = real_start + host_page_size - 1; host_start = g2h_untagged(real_start); /* Get the protection of the target pages outside the mapping. */ @@ -304,12 +306,12 @@ static bool mmap_frag(abi_ulong real_start, abi_ulong start, abi_ulong last, * outside of the fragment we need to map. Allocate a new host * page to cover, discarding whatever else may have been present. */ - void *p = mmap(host_start, qemu_host_page_size, + void *p = mmap(host_start, host_page_size, target_to_host_prot(prot), flags | MAP_ANONYMOUS, -1, 0); if (p != host_start) { if (p != MAP_FAILED) { - munmap(p, qemu_host_page_size); + munmap(p, host_page_size); errno = EEXIST; } return false; @@ -324,7 +326,7 @@ static bool mmap_frag(abi_ulong real_start, abi_ulong start, abi_ulong last, /* Adjust protection to be able to write. */ if (!(host_prot_old & PROT_WRITE)) { host_prot_old |= PROT_WRITE; - mprotect(host_start, qemu_host_page_size, host_prot_old); + mprotect(host_start, host_page_size, host_prot_old); } /* Read or zero the new guest pages. */ @@ -338,7 +340,7 @@ static bool mmap_frag(abi_ulong real_start, abi_ulong start, abi_ulong last, /* Put final protection */ if (host_prot_new != host_prot_old) { - mprotect(host_start, qemu_host_page_size, host_prot_new); + mprotect(host_start, host_page_size, host_prot_new); } return true; } @@ -373,17 +375,18 @@ static abi_ulong mmap_find_vma_reserved(abi_ulong start, abi_ulong size, */ abi_ulong mmap_find_vma(abi_ulong start, abi_ulong size, abi_ulong align) { + int host_page_size = qemu_real_host_page_size(); void *ptr, *prev; abi_ulong addr; int wrapped, repeat; - align = MAX(align, qemu_host_page_size); + align = MAX(align, host_page_size); /* If 'start' == 0, then a default start address is used. */ if (start == 0) { start = mmap_next_start; } else { - start &= qemu_host_page_mask; + start &= -host_page_size; } start = ROUND_UP(start, align); @@ -492,6 +495,7 @@ abi_ulong mmap_find_vma(abi_ulong start, abi_ulong size, abi_ulong align) abi_long target_mmap(abi_ulong start, abi_ulong len, int target_prot, int flags, int fd, off_t offset) { + int host_page_size = qemu_real_host_page_size(); abi_ulong ret, last, real_start, real_last, retaddr, host_len; abi_ulong passthrough_start = -1, passthrough_last = 0; int page_flags; @@ -537,8 +541,8 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, int target_prot, } } - real_start = start & qemu_host_page_mask; - host_offset = offset & qemu_host_page_mask; + real_start = start & -host_page_size; + host_offset = offset & -host_page_size; /* * If the user is asking for the kernel to find a location, do that @@ -567,8 +571,7 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, int target_prot, * may need to truncate file maps at EOF and add extra anonymous pages * up to the targets page boundary. */ - if ((qemu_real_host_page_size() < qemu_host_page_size) && - !(flags & MAP_ANONYMOUS)) { + if (host_page_size < TARGET_PAGE_SIZE && !(flags & MAP_ANONYMOUS)) { struct stat sb; if (fstat(fd, &sb) == -1) { @@ -595,11 +598,7 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, int target_prot, host_len = HOST_PAGE_ALIGN(host_len); host_prot = target_to_host_prot(target_prot); - /* - * Note: we prefer to control the mapping address. It is - * especially important if qemu_host_page_size > - * qemu_real_host_page_size. - */ + /* Note: we prefer to control the mapping address. */ p = mmap(g2h_untagged(start), host_len, host_prot, flags | MAP_FIXED | MAP_ANONYMOUS, -1, 0); if (p == MAP_FAILED) { @@ -665,7 +664,7 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, int target_prot, * aligned, so we read it */ if (!(flags & MAP_ANONYMOUS) && - (offset & ~qemu_host_page_mask) != (start & ~qemu_host_page_mask)) { + (offset & (host_page_size - 1)) != (start & (host_page_size - 1))) { /* * msync() won't work here, so we return an error if write is * possible while it is a shared mapping @@ -694,7 +693,7 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, int target_prot, /* handle the start of the mapping */ if (start > real_start) { - if (real_last == real_start + qemu_host_page_size - 1) { + if (real_last == real_start + host_page_size - 1) { /* one single host page */ if (!mmap_frag(real_start, start, last, target_prot, flags, fd, offset)) { @@ -703,21 +702,21 @@ abi_long target_mmap(abi_ulong start, abi_ulong len, int target_prot, goto the_end1; } if (!mmap_frag(real_start, start, - real_start + qemu_host_page_size - 1, + real_start + host_page_size - 1, target_prot, flags, fd, offset)) { goto fail; } - real_start += qemu_host_page_size; + real_start += host_page_size; } /* handle the end of the mapping */ if (last < real_last) { - abi_ulong real_page = real_last - qemu_host_page_size + 1; + abi_ulong real_page = real_last - host_page_size + 1; if (!mmap_frag(real_page, real_page, last, target_prot, flags, fd, offset + real_page - start)) { goto fail; } - real_last -= qemu_host_page_size; + real_last -= host_page_size; } /* map the middle (easier) */ @@ -784,6 +783,7 @@ fail: static int mmap_reserve_or_unmap(abi_ulong start, abi_ulong len) { + int host_page_size = qemu_real_host_page_size(); abi_ulong real_start; abi_ulong real_last; abi_ulong real_len; @@ -793,7 +793,7 @@ static int mmap_reserve_or_unmap(abi_ulong start, abi_ulong len) int prot; last = start + len - 1; - real_start = start & qemu_host_page_mask; + real_start = start & -host_page_size; real_last = HOST_PAGE_ALIGN(last) - 1; /* @@ -802,7 +802,7 @@ static int mmap_reserve_or_unmap(abi_ulong start, abi_ulong len) * The single page special case is required for the last page, * lest real_start overflow to zero. */ - if (real_last - real_start < qemu_host_page_size) { + if (real_last - real_start < host_page_size) { prot = 0; for (a = real_start; a < start; a += TARGET_PAGE_SIZE) { prot |= page_get_flags(a); @@ -818,14 +818,14 @@ static int mmap_reserve_or_unmap(abi_ulong start, abi_ulong len) prot |= page_get_flags(a); } if (prot != 0) { - real_start += qemu_host_page_size; + real_start += host_page_size; } for (prot = 0, a = last; a < real_last; a += TARGET_PAGE_SIZE) { prot |= page_get_flags(a + 1); } if (prot != 0) { - real_last -= qemu_host_page_size; + real_last -= host_page_size; } if (real_last < real_start) {
Use qemu_real_host_page_size instead. Signed-off-by: Richard Henderson <richard.henderson@linaro.org> --- linux-user/mmap.c | 66 +++++++++++++++++++++++------------------------ 1 file changed, 33 insertions(+), 33 deletions(-)