Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
---
linux-user/qemu.h | 11 +++++++++++
linux-user/elfload.c | 4 ++--
linux-user/linuxload.c | 44 ++++++++++++++++++++++++++++++++++++++++++
3 files changed, 57 insertions(+), 2 deletions(-)
diff --git a/linux-user/qemu.h b/linux-user/qemu.h
index dafaae6293..255182e133 100644
--- a/linux-user/qemu.h
+++ b/linux-user/qemu.h
@@ -199,6 +199,17 @@ bool imgsrc_read(void *dst, off_t offset, size_t len,
void *imgsrc_read_alloc(off_t offset, size_t len,
const ImageSource *img, Error **errp);
+/**
+ * imgsrc_mmap: Map from ImageSource
+ *
+ * If @src has a file descriptor, pass on to target_mmap. Otherwise,
+ * this is "mapping" from a host buffer, which resolves to memcpy.
+ * Therefore, flags must be MAP_PRIVATE | MAP_FIXED; the argument is
+ * retained for clarity.
+ */
+abi_long imgsrc_mmap(abi_ulong start, abi_ulong len, int prot,
+ int flags, const ImageSource *src, abi_ulong offset);
+
/* Read a good amount of data initially, to hopefully get all the
program headers loaded. */
#define BPRM_BUF_SIZE 1024
diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index 490b374d13..ec4b5f9d54 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -2837,9 +2837,9 @@ static void load_elf_image(const char *image_name, const
ImageSource *src,
*/
if (eppnt->p_filesz != 0) {
vaddr_len = TARGET_ELF_PAGELENGTH(eppnt->p_filesz + vaddr_po);
- error = target_mmap(vaddr_ps, vaddr_len, elf_prot,
+ error = imgsrc_mmap(vaddr_ps, vaddr_len, elf_prot,
MAP_PRIVATE | MAP_FIXED,
- src->fd, eppnt->p_offset - vaddr_po);
+ src, eppnt->p_offset - vaddr_po);
if (error == -1) {
goto exit_mmap;
diff --git a/linux-user/linuxload.c b/linux-user/linuxload.c
index d0d3f2ed0e..a437a22b49 100644
--- a/linux-user/linuxload.c
+++ b/linux-user/linuxload.c
@@ -208,3 +208,47 @@ void *imgsrc_read_alloc(off_t offset, size_t len,
}
return alloc;
}
+
+abi_long imgsrc_mmap(abi_ulong start, abi_ulong len, int prot,
+ int flags, const ImageSource *src, abi_ulong offset)
+{
+ abi_long ret;
+ int prot_write;
+ void *haddr;
+
+ assert(flags == (MAP_PRIVATE | MAP_FIXED));
+
+ if (src->fd >= 0) {
+ return target_mmap(start, len, prot, flags, src->fd, offset);
+ }
+
+ /*
+ * This case is for the vdso; we don't expect bad images.
+ * The mmap may extend beyond the end of the image, especially
+ * to the end of the page. Zero fill.
+ */
+ assert(offset < src->cache_size);
+
+ prot_write = prot | PROT_WRITE;
+ ret = target_mmap(start, len, prot_write, flags | MAP_ANON, -1, 0);
+ if (ret == -1) {
+ return ret;
+ }
+
+ haddr = lock_user(VERIFY_WRITE, start, len, 0);
+ assert(haddr != NULL);
+ if (offset + len < src->cache_size) {
+ memcpy(haddr, src->cache + offset, len);
+ } else {
+ size_t rest = src->cache_size - offset;
+ memcpy(haddr, src->cache + offset, rest);
+ memset(haddr + rest, 0, len - rest);
+ }
+ unlock_user(haddr, start, len);
+
+ if (prot != prot_write) {
+ target_mprotect(start, len, prot);
+ }
+
+ return ret;
+}
--
2.25.1
