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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /arch/x86/um/stub_32.S
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/um/stub_32.S')
-rw-r--r--arch/x86/um/stub_32.S56
1 files changed, 56 insertions, 0 deletions
diff --git a/arch/x86/um/stub_32.S b/arch/x86/um/stub_32.S
new file mode 100644
index 000000000..8291899e6
--- /dev/null
+++ b/arch/x86/um/stub_32.S
@@ -0,0 +1,56 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <as-layout.h>
+
+.section .__syscall_stub, "ax"
+
+ .globl batch_syscall_stub
+batch_syscall_stub:
+ /* %esp comes in as "top of page" */
+ mov %esp, %ecx
+ /* %esp has pointer to first operation */
+ add $8, %esp
+again:
+ /* load length of additional data */
+ mov 0x0(%esp), %eax
+
+ /* if(length == 0) : end of list */
+ /* write possible 0 to header */
+ mov %eax, 0x4(%ecx)
+ cmpl $0, %eax
+ jz done
+
+ /* save current pointer */
+ mov %esp, 0x4(%ecx)
+
+ /* skip additional data */
+ add %eax, %esp
+
+ /* load syscall-# */
+ pop %eax
+
+ /* load syscall params */
+ pop %ebx
+ pop %ecx
+ pop %edx
+ pop %esi
+ pop %edi
+ pop %ebp
+
+ /* execute syscall */
+ int $0x80
+
+ /* restore top of page pointer in %ecx */
+ mov %esp, %ecx
+ andl $(~UM_KERN_PAGE_SIZE) + 1, %ecx
+
+ /* check return value */
+ pop %ebx
+ cmp %ebx, %eax
+ je again
+
+done:
+ /* save return value */
+ mov %eax, (%ecx)
+
+ /* stop */
+ int3