From: imp@bsdimp.com
To: qemu-devel@nongnu.org
Cc: kevans@freebsd.org,
Richard Henderson <richard.henderson@linaro.org>,
Warner Losh <imp@bsdimp.com>
Subject: [PULL 14/42] bsd-user: elfload: simplify bswap a bit.
Date: Tue, 7 Sep 2021 15:53:04 -0600 [thread overview]
Message-ID: <20210907215332.30737-15-imp@bsdimp.com> (raw)
In-Reply-To: <20210907215332.30737-1-imp@bsdimp.com>
From: Warner Losh <imp@bsdimp.com>
Reduce the number of ifdefs by always calling the swapping routine, but
making them empty when swapping isn't needed.
Signed-off-by: Warner Losh <imp@bsdimp.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
---
bsd-user/elfload.c | 97 ++++++++++++++++++++++------------------------
1 file changed, 47 insertions(+), 50 deletions(-)
diff --git a/bsd-user/elfload.c b/bsd-user/elfload.c
index 4f3fa83c2c..ccb1744800 100644
--- a/bsd-user/elfload.c
+++ b/bsd-user/elfload.c
@@ -67,13 +67,13 @@
static inline void memcpy_fromfs(void *to, const void *from, unsigned long n)
{
- memcpy(to, from, n);
+ memcpy(to, from, n);
}
#ifdef BSWAP_NEEDED
static void bswap_ehdr(struct elfhdr *ehdr)
{
- bswap16s(&ehdr->e_type); /* Object file type */
+ bswap16s(&ehdr->e_type); /* Object file type */
bswap16s(&ehdr->e_machine); /* Architecture */
bswap32s(&ehdr->e_version); /* Object file version */
bswaptls(&ehdr->e_entry); /* Entry point virtual address */
@@ -81,37 +81,45 @@ static void bswap_ehdr(struct elfhdr *ehdr)
bswaptls(&ehdr->e_shoff); /* Section header table file offset */
bswap32s(&ehdr->e_flags); /* Processor-specific flags */
bswap16s(&ehdr->e_ehsize); /* ELF header size in bytes */
- bswap16s(&ehdr->e_phentsize); /* Program header table entry size */
+ bswap16s(&ehdr->e_phentsize); /* Program header table entry size */
bswap16s(&ehdr->e_phnum); /* Program header table entry count */
- bswap16s(&ehdr->e_shentsize); /* Section header table entry size */
+ bswap16s(&ehdr->e_shentsize); /* Section header table entry size */
bswap16s(&ehdr->e_shnum); /* Section header table entry count */
- bswap16s(&ehdr->e_shstrndx); /* Section header string table index */
+ bswap16s(&ehdr->e_shstrndx); /* Section header string table index */
}
-static void bswap_phdr(struct elf_phdr *phdr)
+static void bswap_phdr(struct elf_phdr *phdr, int phnum)
{
- bswap32s(&phdr->p_type); /* Segment type */
- bswaptls(&phdr->p_offset); /* Segment file offset */
- bswaptls(&phdr->p_vaddr); /* Segment virtual address */
- bswaptls(&phdr->p_paddr); /* Segment physical address */
- bswaptls(&phdr->p_filesz); /* Segment size in file */
- bswaptls(&phdr->p_memsz); /* Segment size in memory */
- bswap32s(&phdr->p_flags); /* Segment flags */
- bswaptls(&phdr->p_align); /* Segment alignment */
+ int i;
+
+ for (i = 0; i < phnum; i++, phdr++) {
+ bswap32s(&phdr->p_type); /* Segment type */
+ bswap32s(&phdr->p_flags); /* Segment flags */
+ bswaptls(&phdr->p_offset); /* Segment file offset */
+ bswaptls(&phdr->p_vaddr); /* Segment virtual address */
+ bswaptls(&phdr->p_paddr); /* Segment physical address */
+ bswaptls(&phdr->p_filesz); /* Segment size in file */
+ bswaptls(&phdr->p_memsz); /* Segment size in memory */
+ bswaptls(&phdr->p_align); /* Segment alignment */
+ }
}
-static void bswap_shdr(struct elf_shdr *shdr)
+static void bswap_shdr(struct elf_shdr *shdr, int shnum)
{
- bswap32s(&shdr->sh_name);
- bswap32s(&shdr->sh_type);
- bswaptls(&shdr->sh_flags);
- bswaptls(&shdr->sh_addr);
- bswaptls(&shdr->sh_offset);
- bswaptls(&shdr->sh_size);
- bswap32s(&shdr->sh_link);
- bswap32s(&shdr->sh_info);
- bswaptls(&shdr->sh_addralign);
- bswaptls(&shdr->sh_entsize);
+ int i;
+
+ for (i = 0; i < shnum; i++, shdr++) {
+ bswap32s(&shdr->sh_name);
+ bswap32s(&shdr->sh_type);
+ bswaptls(&shdr->sh_flags);
+ bswaptls(&shdr->sh_addr);
+ bswaptls(&shdr->sh_offset);
+ bswaptls(&shdr->sh_size);
+ bswap32s(&shdr->sh_link);
+ bswap32s(&shdr->sh_info);
+ bswaptls(&shdr->sh_addralign);
+ bswaptls(&shdr->sh_entsize);
+ }
}
static void bswap_sym(struct elf_sym *sym)
@@ -121,7 +129,15 @@ static void bswap_sym(struct elf_sym *sym)
bswaptls(&sym->st_size);
bswap16s(&sym->st_shndx);
}
-#endif
+
+#else /* ! BSWAP_NEEDED */
+
+static void bswap_ehdr(struct elfhdr *ehdr) { }
+static void bswap_phdr(struct elf_phdr *phdr, int phnum) { }
+static void bswap_shdr(struct elf_shdr *shdr, int shnum) { }
+static void bswap_sym(struct elf_sym *sym) { }
+
+#endif /* ! BSWAP_NEEDED */
/*
* 'copy_elf_strings()' copies argument/envelope strings from user
@@ -367,9 +383,7 @@ static abi_ulong load_elf_interp(struct elfhdr *interp_elf_ex,
last_bss = 0;
error = 0;
-#ifdef BSWAP_NEEDED
bswap_ehdr(interp_elf_ex);
-#endif
/* First of all, some simple consistency checks */
if ((interp_elf_ex->e_type != ET_EXEC &&
interp_elf_ex->e_type != ET_DYN) ||
@@ -410,12 +424,7 @@ static abi_ulong load_elf_interp(struct elfhdr *interp_elf_ex,
free(elf_phdata);
return retval;
}
-#ifdef BSWAP_NEEDED
- eppnt = elf_phdata;
- for (i = 0; i<interp_elf_ex->e_phnum; i++, eppnt++) {
- bswap_phdr(eppnt);
- }
-#endif
+ bswap_phdr(elf_phdata, interp_elf_ex->e_phnum);
if (interp_elf_ex->e_type == ET_DYN) {
/* in order to avoid hardcoding the interpreter load
@@ -560,9 +569,7 @@ static void load_symbols(struct elfhdr *hdr, int fd)
for (i = 0; i < hdr->e_shnum; i++) {
if (read(fd, &sechdr, sizeof(sechdr)) != sizeof(sechdr))
return;
-#ifdef BSWAP_NEEDED
- bswap_shdr(&sechdr);
-#endif
+ bswap_shdr(&sechdr, 1);
if (sechdr.sh_type == SHT_SYMTAB) {
symtab = sechdr;
lseek(fd, hdr->e_shoff
@@ -570,9 +577,7 @@ static void load_symbols(struct elfhdr *hdr, int fd)
if (read(fd, &strtab, sizeof(strtab))
!= sizeof(strtab))
return;
-#ifdef BSWAP_NEEDED
- bswap_shdr(&strtab);
-#endif
+ bswap_shdr(&strtab, 1);
goto found;
}
}
@@ -605,9 +610,7 @@ static void load_symbols(struct elfhdr *hdr, int fd)
i = 0;
while (i < nsyms) {
-#ifdef BSWAP_NEEDED
bswap_sym(syms + i);
-#endif
// Throw away entries which we do not need.
if (syms[i].st_shndx == SHN_UNDEF ||
syms[i].st_shndx >= SHN_LORESERVE ||
@@ -679,9 +682,7 @@ int load_elf_binary(struct bsd_binprm *bprm, struct target_pt_regs *regs,
load_addr = 0;
load_bias = 0;
elf_ex = *((struct elfhdr *) bprm->buf); /* exec-header */
-#ifdef BSWAP_NEEDED
bswap_ehdr(&elf_ex);
-#endif
/* First of all, some simple consistency checks */
if ((elf_ex.e_type != ET_EXEC && elf_ex.e_type != ET_DYN) ||
@@ -715,12 +716,8 @@ int load_elf_binary(struct bsd_binprm *bprm, struct target_pt_regs *regs,
return -errno;
}
-#ifdef BSWAP_NEEDED
- elf_ppnt = elf_phdata;
- for (i = 0; i < elf_ex.e_phnum; i++, elf_ppnt++) {
- bswap_phdr(elf_ppnt);
- }
-#endif
+ bswap_phdr(elf_phdata, elf_ex.e_phnum);
+
elf_ppnt = elf_phdata;
elf_bss = 0;
--
2.32.0
next prev parent reply other threads:[~2021-09-07 22:07 UTC|newest]
Thread overview: 50+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-07 21:52 [PULL 00/42] bsd-user updates to run hello world imp
2021-09-07 21:52 ` [PULL 01/42] bsd-user: remove sparc and sparc64 imp
2021-09-07 21:52 ` [PULL 02/42] bsd-user: add copyright header to elfload.c imp
2021-09-07 21:52 ` [PULL 03/42] bsd-user: Add Stacey's copyright to main.c imp
2021-09-07 21:52 ` [PULL 04/42] bsd-user: add license to bsdload.c imp
2021-09-07 21:52 ` [PULL 05/42] bsd-user: style nits: bsdload.c whitespace to qemu standard imp
2021-09-07 21:52 ` [PULL 06/42] bsd-user: Remove all non-x86 code from elfload.c imp
2021-09-07 21:52 ` [PULL 07/42] bsd-user: move arch specific defines out of elfload.c imp
2021-09-07 21:52 ` [PULL 08/42] bsd-user: pass the bsd_param into loader_exec imp
2021-09-07 21:52 ` [PULL 09/42] bsd-user: Fix calculation of size to allocate imp
2021-09-07 21:53 ` [PULL 10/42] bsd-user: implement path searching imp
2021-09-07 21:53 ` [PULL 11/42] bsd-user: Eliminate elf personality imp
2021-09-07 21:53 ` [PULL 12/42] bsd-user: remove a.out support imp
2021-09-07 21:53 ` [PULL 13/42] bsd-user: TARGET_NGROUPS unused in this file, remove imp
2021-09-07 21:53 ` imp [this message]
2021-09-07 21:53 ` [PULL 15/42] bsd-user: assume pthreads and support of __thread imp
2021-09-07 21:53 ` [PULL 16/42] bsd-user: add host-os.h imp
2021-09-07 21:53 ` [PULL 17/42] bsd-user: Include host-os.h from main imp
2021-09-07 21:53 ` [PULL 18/42] bsd-user: save the path to the qemu emulator imp
2021-09-07 21:53 ` [PULL 19/42] bsd-user: start to move target CPU functions to target_arch* imp
2021-09-07 21:53 ` [PULL 20/42] bsd-user: Move per-cpu code into target_arch_cpu.h imp
2021-09-07 21:53 ` [PULL 21/42] bsd-user: pull in target_arch_thread.h update target_arch_elf.h imp
2021-09-07 21:53 ` [PULL 22/42] bsd-user: Include more things in qemu.h imp
2021-09-07 21:53 ` [PULL 23/42] bsd-user: define max args in terms of pages imp
2021-09-07 21:53 ` [PULL 24/42] bsd-user: Create target specific vmparam.h imp
2021-09-07 21:53 ` [PULL 25/42] bsd-user: Add system independent stack, data and text limiting imp
2021-09-07 21:53 ` [PULL 26/42] bsd-user: *BSD specific siginfo defintions imp
2021-09-07 21:53 ` [PULL 27/42] bsd-user: Implement --seed and initialize random state imp
2021-09-07 21:53 ` [PULL 28/42] bsd-user: Move stack initializtion into a per-os file imp
2021-09-07 21:53 ` [PULL 29/42] bsd-user: Add architecture specific signal tramp code imp
2021-09-07 21:53 ` [PULL 30/42] bsd-user: elf cleanup imp
2021-09-07 21:53 ` [PULL 31/42] bsd-user: Remove dead #ifdefs from elfload.c imp
2021-09-07 21:53 ` [PULL 32/42] bsd-user: Rewrite target system call definintion glue imp
2021-09-07 21:53 ` [PULL 33/42] bsd-user: update debugging in mmap.c imp
2021-09-07 21:53 ` [PULL 34/42] bsd-user: Add target_arch_reg to describe a target's register set imp
2021-09-07 21:53 ` [PULL 35/42] bsd-user: Add target_os_user.h to capture the user/kernel structures imp
2021-09-07 21:53 ` [PULL 36/42] bsd-user: add stubbed out core dump support imp
2021-09-07 21:53 ` [PULL 37/42] bsd-user: elfload.c style catch up patch imp
2021-09-07 21:53 ` [PULL 38/42] bsd-user: Refactor load_elf_sections and is_target_elf_binary imp
2021-09-07 21:53 ` [PULL 39/42] bsd-user: move gemu_log to later in the file imp
2021-09-07 21:53 ` [PULL 40/42] bsd-user: Implement interlock for atomic operations imp
2021-09-07 21:53 ` [PULL 41/42] bsd-user: Add '-0 argv0' option to bsd-user/main.c imp
2021-09-07 21:53 ` [PULL 42/42] bsd-user: Update mapping to handle reserved and starting conditions imp
2021-09-09 15:00 ` [PULL 00/42] bsd-user updates to run hello world Peter Maydell
2021-09-09 15:12 ` Warner Losh
2021-09-09 15:21 ` Daniel P. Berrangé
2021-09-09 16:31 ` Philippe Mathieu-Daudé
2021-09-10 20:35 ` Warner Losh
2021-09-09 16:29 ` Philippe Mathieu-Daudé
2021-09-10 20:31 ` Warner Losh
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