From: Nikhil Devshatwar <[email protected]> ivshmem protocol does not describe a fixed size for the rw, input and output regions. For each platform, the uio driver will populate this information in the sysfs.
Extract the size from sysfs maps entries and use it for mapping different regions. This will make the demo generic such that it will work on all platforms with different sizes for ivshmem. Signed-off-by: Nikhil Devshatwar <[email protected]> --- tools/ivshmem-demo.c | 50 ++++++++++++++++++++++++++++++++++++-------- 1 file changed, 41 insertions(+), 9 deletions(-) diff --git a/tools/ivshmem-demo.c b/tools/ivshmem-demo.c index 8201ad15..163653e1 100644 --- a/tools/ivshmem-demo.c +++ b/tools/ivshmem-demo.c @@ -17,6 +17,7 @@ #include <signal.h> #include <stdio.h> #include <stdint.h> +#include <stdlib.h> #include <string.h> #include <unistd.h> #include <sys/mman.h> @@ -44,6 +45,25 @@ static inline void mmio_write32(void *address, uint32_t value) *(volatile uint32_t *)address = value; } +static int uio_read_mem_size(char *devpath, int idx) +{ + char sysfs_path[64]; + char output[20] = ""; + int fd, ret, size; + + snprintf(sysfs_path, sizeof(sysfs_path), + "/sys/class/uio/%s/maps/map%d/size", + basename(devpath), idx); + fd = open(sysfs_path, O_RDONLY); + if (fd < 0) + return fd; + ret = read(fd, output, sizeof(output)); + if (ret < 0) + return ret; + sscanf(output, "0x%x", &size); + return size; +} + static void print_shmem(void) { printf("state[0] = %d\n", state[0]); @@ -67,7 +87,9 @@ int main(int argc, char *argv[]) sigset_t sigset; char *path; int has_msix; - int ret; + int ret, size, offset, pgsize; + + pgsize = getpagesize(); if (argc < 2) path = strdup("/dev/uio0"); @@ -82,29 +104,39 @@ int main(int argc, char *argv[]) "/sys/class/uio/%s/device/msi_irqs", basename(path)); has_msix = access(sysfs_path, R_OK) == 0; - regs = mmap(NULL, 4096, PROT_READ | PROT_WRITE, MAP_SHARED, - fds[0].fd, 0); + offset = 0; + size = uio_read_mem_size(path, 0); + regs = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, + fds[0].fd, offset); if (regs == MAP_FAILED) error(1, errno, "mmap(regs)"); id = mmio_read32(®s->id); printf("ID = %d\n", id); - state = mmap(NULL, 4096, PROT_READ, MAP_SHARED, fds[0].fd, 4096 * 1); + offset += pgsize; + size = uio_read_mem_size(path, 1); + state = mmap(NULL, size, PROT_READ, MAP_SHARED, fds[0].fd, offset); if (state == MAP_FAILED) error(1, errno, "mmap(state)"); - rw = mmap(NULL, 4096 * 9, PROT_READ | PROT_WRITE, MAP_SHARED, - fds[0].fd, 4096 * 2); + offset += pgsize; + size = uio_read_mem_size(path, 2); + rw = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, + fds[0].fd, offset); if (rw == MAP_FAILED) error(1, errno, "mmap(rw)"); - in = mmap(NULL, 4096 * 6, PROT_READ, MAP_SHARED, fds[0].fd, 4096 * 3); + offset += pgsize; + size = uio_read_mem_size(path, 3); + in = mmap(NULL, size, PROT_READ, MAP_SHARED, fds[0].fd, offset); if (in == MAP_FAILED) error(1, errno, "mmap(in)"); - out = mmap(NULL, 4096 * 2, PROT_READ | PROT_WRITE, MAP_SHARED, - fds[0].fd, 4096 * 4); + offset += pgsize; + size = uio_read_mem_size(path, 4); + out = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, + fds[0].fd, offset); if (out == MAP_FAILED) error(1, errno, "mmap(out)"); -- 2.17.1 -- You received this message because you are subscribed to the Google Groups "Jailhouse" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/jailhouse-dev/20200608104255.18358-7-nikhil.nd%40ti.com.
