[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[PATCH 35/45] linux-user: Use page_find_range_empty for mmap_find_vma_re
From: |
Richard Henderson |
Subject: |
[PATCH 35/45] linux-user: Use page_find_range_empty for mmap_find_vma_reserved |
Date: |
Sun, 9 Jul 2023 19:29:22 +0100 |
Use the interval tree to find empty space, rather than
probing each page in turn.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230707204054.8792-19-richard.henderson@linaro.org>
---
linux-user/mmap.c | 52 ++++++-----------------------------------------
1 file changed, 6 insertions(+), 46 deletions(-)
diff --git a/linux-user/mmap.c b/linux-user/mmap.c
index c4b2515271..738b9b797d 100644
--- a/linux-user/mmap.c
+++ b/linux-user/mmap.c
@@ -318,55 +318,15 @@ unsigned long last_brk;
static abi_ulong mmap_find_vma_reserved(abi_ulong start, abi_ulong size,
abi_ulong align)
{
- abi_ulong addr, end_addr, incr = qemu_host_page_size;
- int prot;
- bool looped = false;
+ target_ulong ret;
- if (size > reserved_va) {
- return (abi_ulong)-1;
+ ret = page_find_range_empty(start, reserved_va, size, align);
+ if (ret == -1 && start > mmap_min_addr) {
+ /* Restart at the beginning of the address space. */
+ ret = page_find_range_empty(mmap_min_addr, start - 1, size, align);
}
- /* Note that start and size have already been aligned by mmap_find_vma. */
-
- end_addr = start + size;
- /*
- * Start at the top of the address space, ignoring the last page.
- * If reserved_va == UINT32_MAX, then end_addr wraps to 0,
- * throwing the rest of the calculations off.
- * TODO: rewrite using last_addr instead.
- * TODO: use the interval tree instead of probing every page.
- */
- if (start > reserved_va - size) {
- end_addr = ((reserved_va - size) & -align) + size;
- looped = true;
- }
-
- /* Search downward from END_ADDR, checking to see if a page is in use. */
- addr = end_addr;
- while (1) {
- addr -= incr;
- if (addr > end_addr) {
- if (looped) {
- /* Failure. The entire address space has been searched. */
- return (abi_ulong)-1;
- }
- /* Re-start at the top of the address space (see above). */
- addr = end_addr = ((reserved_va - size) & -align) + size;
- looped = true;
- } else {
- prot = page_get_flags(addr);
- if (prot) {
- /* Page in use. Restart below this page. */
- addr = end_addr = ((addr - size) & -align) + size;
- } else if (addr && addr + size == end_addr) {
- /* Success! All pages between ADDR and END_ADDR are free. */
- if (start == mmap_next_start) {
- mmap_next_start = addr;
- }
- return addr;
- }
- }
- }
+ return ret;
}
/*
--
2.34.1
- [PULL 27/37] target/arm: Use aesenc_MC, (continued)
- [PULL 27/37] target/arm: Use aesenc_MC, Richard Henderson, 2023/07/09
- [PATCH 30/45] linux-user: Widen target_mmap offset argument to off_t, Richard Henderson, 2023/07/09
- [PATCH 29/45] linux-user: Split out target_to_host_prot, Richard Henderson, 2023/07/09
- [PATCH 32/45] linux-user: Rewrite mmap_frag, Richard Henderson, 2023/07/09
- [PULL 32/37] target/riscv: Use aesenc_SB_SR_MC_AK, Richard Henderson, 2023/07/09
- [PULL 34/37] crypto: Remove AES_shifts, AES_ishifts, Richard Henderson, 2023/07/09
- [PATCH 36/45] linux-user: Use 'last' instead of 'end' in target_mmap, Richard Henderson, 2023/07/09
- [PATCH 28/45] linux-user: Implement MAP_FIXED_NOREPLACE, Richard Henderson, 2023/07/09
- [PULL 33/37] target/riscv: Use aesdec_ISB_ISR_IMC_AK, Richard Henderson, 2023/07/09
- [PATCH 33/45] accel/tcg: Introduce page_find_range_empty, Richard Henderson, 2023/07/09
- [PATCH 35/45] linux-user: Use page_find_range_empty for mmap_find_vma_reserved,
Richard Henderson <=
- [PATCH 34/45] bsd-user: Use page_find_range_empty for mmap_find_vma_reserved, Richard Henderson, 2023/07/09
- [PATCH 22/45] linux-user/strace: Expand struct flags to hold a mask, Richard Henderson, 2023/07/09
- [PULL 23/37] target/i386: Use aesdec_ISB_ISR_IMC_AK, Richard Henderson, 2023/07/09
- [PATCH 27/45] bsd-user: Use page_check_range_empty for MAP_EXCL, Richard Henderson, 2023/07/09
- [PATCH 40/45] accel/tcg: Accept more page flags in page_check_range, Richard Henderson, 2023/07/09
- [PULL 37/37] crypto: Unexport AES_*_rot, AES_TeN, AES_TdN, Richard Henderson, 2023/07/09
- [PATCH 25/45] linux-user: Populate more bits in mmap_flags_tbl, Richard Henderson, 2023/07/09
- [PULL 30/37] target/riscv: Use aesdec_ISB_ISR_AK, Richard Henderson, 2023/07/09
- [PULL 35/37] crypto: Implement aesdec_IMC with AES_imc_rot, Richard Henderson, 2023/07/09
- [PATCH 41/45] accel/tcg: Return bool from page_check_range, Richard Henderson, 2023/07/09