read/write: dont copy to a buffer

This commit is contained in:
Matheus
2024-09-18 22:44:18 -03:00
parent 570d51dcf1
commit 0a7bd14049
2 changed files with 7 additions and 17 deletions
+4 -8
View File
@@ -10,10 +10,8 @@ syscallret_t syscall_read(context_t *context, int fd, void *buffer, size_t size)
.ret = -1
};
void *kernelbuff = vmm_map(NULL, size == 0 ? 1 : size, VMM_FLAGS_ALLOCATE, ARCH_MMU_FLAGS_READ | ARCH_MMU_FLAGS_WRITE | ARCH_MMU_FLAGS_NOEXEC, NULL);
if (kernelbuff == NULL) {
printf("read enomem: %d %p %lu\n", fd, buffer, size);
ret.errno = ENOMEM;
if (IS_USER_ADDRESS(buffer) == false) {
ret.errno = EFAULT;
return ret;
}
@@ -32,18 +30,16 @@ syscallret_t syscall_read(context_t *context, int fd, void *buffer, size_t size)
size_t bytesread;
uintmax_t offset = file->offset;
ret.errno = vfs_read(file->vnode, kernelbuff, size, file->offset, &bytesread, fileflagstovnodeflags(file->flags));
ret.errno = vfs_read(file->vnode, buffer, size, file->offset, &bytesread, fileflagstovnodeflags(file->flags));
if (ret.errno)
goto cleanup;
file->offset = offset + bytesread;
ret.errno = usercopy_touser(buffer, kernelbuff, bytesread);
ret.ret = ret.errno ? -1 : bytesread;
ret.ret = bytesread;
cleanup:
if (file)
fd_release(file);
vmm_unmap(kernelbuff, size == 0 ? 1 : size, 0);
return ret;
}
+3 -9
View File
@@ -8,9 +8,8 @@ syscallret_t syscall_write(context_t *context, int fd, void *buffer, size_t size
.ret = -1
};
void *kernelbuff = vmm_map(NULL, size == 0 ? 1 : size, VMM_FLAGS_ALLOCATE, ARCH_MMU_FLAGS_READ | ARCH_MMU_FLAGS_WRITE | ARCH_MMU_FLAGS_NOEXEC, NULL);
if (kernelbuff == NULL) {
ret.errno = ENOMEM;
if (IS_USER_ADDRESS(buffer) == false) {
ret.errno = EFAULT;
return ret;
}
@@ -21,10 +20,6 @@ syscallret_t syscall_write(context_t *context, int fd, void *buffer, size_t size
goto cleanup;
}
ret.errno = usercopy_fromuser(kernelbuff, buffer, size);
if (ret.errno)
goto cleanup;
if (size == 0) {
ret.ret = 0;
ret.errno = 0;
@@ -46,7 +41,7 @@ syscallret_t syscall_write(context_t *context, int fd, void *buffer, size_t size
offset = attr.size;
}
ret.errno = vfs_write(file->vnode, kernelbuff, size, offset, &byteswritten, fileflagstovnodeflags(file->flags));
ret.errno = vfs_write(file->vnode, buffer, size, offset, &byteswritten, fileflagstovnodeflags(file->flags));
if (ret.errno)
goto cleanup;
@@ -58,6 +53,5 @@ cleanup:
if (file)
fd_release(file);
vmm_unmap(kernelbuff, size == 0 ? 1 : size, 0);
return ret;
}