[PATCH libpciaccess] hurd: device_open the pre-existing pci server and use dir_readdir RPC

[Damien Zammit]

This patch for libpciaccess goes in lockstep with 
the previous patches I sent for hurd.

---
 src/hurd_pci.c | 125 ++++++++++++++++++++++++++++++++++++++-----------
 1 file changed, 98 insertions(+), 27 deletions(-)

diff --git a/src/hurd_pci.c b/src/hurd_pci.c
index ada7af8..ff14285 100644
--- a/src/hurd_pci.c
+++ b/src/hurd_pci.c
@@ -33,9 +33,12 @@
 #include <sys/mman.h>
 #include <string.h>
 #include <strings.h>
+#include <mach.h>
 #include <hurd.h>
 #include <hurd/pci.h>
 #include <hurd/paths.h>
+#include <hurd/fs.h>
+#include <device/device.h>
 
 #include "x86_pci.h"
 #include "pciaccess.h"
@@ -302,26 +305,74 @@ pci_device_hurd_destroy(struct pci_device *dev)
     mach_port_deallocate (mach_task_self (), d->device_port);
 }
 
+static struct dirent *
+simple_readdir(mach_port_t port, uint32_t *first_entry)
+{
+    struct dirent *e;
+    char *data;
+    int nentries = 0;
+    vm_size_t size;
+
+    dir_readdir (port, &data, &size, *first_entry, 1, 0, &nentries);
+
+    if (nentries == 0) {
+       return NULL;
+    }
+
+    *first_entry = *first_entry + 1;
+    e = (struct dirent *)(data+4);
+    return e;
+}
+
+static struct dirent *
+readdir_wrapper(DIR *dir, mach_port_t port, uint32_t *count)
+{
+    if (dir) {
+        return readdir(dir);
+    } else {
+       return simple_readdir(port, count);
+    }
+}
+
+static int
+closedir_wrapper(DIR *dir)
+{
+    if (dir) {
+        return closedir(dir);
+    }
+    return 0;
+}
+
 /* Walk through the FS tree to see what is allowed for us */
 static int
-enum_devices(const char *parent, int domain,
-    int bus, int dev, int func, tree_level lev)
+enum_devices(mach_port_t pci_port, mach_port_t cwd_port, const char *parent, 
int domain,
+             int bus, int dev, int func, tree_level lev)
 {
     int err, ret;
-    DIR *dir;
-    struct dirent *entry;
+    DIR *dir = NULL;
+    struct dirent *entry = NULL;
     char path[NAME_MAX];
     char server[NAME_MAX];
-    uint32_t reg;
+    uint32_t reg, count = 0;
     size_t toread;
     mach_port_t device_port;
     struct pci_device_private *d, *devices;
 
-    dir = opendir(parent);
-    if (!dir)
-        return errno;
+    if (pci_port == MACH_PORT_NULL) {
+        dir = opendir(parent);
+        if (!dir)
+            return errno;
+    } else {
+        if (lev > LEVEL_FUNC + 1) {
+           return 0;
+       }
+        cwd_port = file_name_lookup_under (pci_port, parent, O_DIRECTORY | 
O_RDWR | O_EXEC, 0);
+        if (cwd_port == MACH_PORT_NULL) {
+           return 0;
+        }
+    }
 
-    while ((entry = readdir(dir)) != 0) {
+    while ((entry = readdir_wrapper(dir, cwd_port, &count)) != NULL) {
         snprintf(path, NAME_MAX, "%s/%s", parent, entry->d_name);
         if (entry->d_type == DT_DIR) {
             if (!strncmp(entry->d_name, ".", NAME_MAX)
@@ -331,7 +382,7 @@ enum_devices(const char *parent, int domain,
             errno = 0;
             ret = strtol(entry->d_name, 0, 16);
             if (errno) {
-                closedir(dir);
+                closedir_wrapper(dir);
                 return errno;
             }
 
@@ -353,14 +404,14 @@ enum_devices(const char *parent, int domain,
                 func = ret;
                 break;
             default:
-                if (closedir(dir) < 0)
+                if (closedir_wrapper(dir) < 0)
                     return errno;
                 return -1;
             }
 
-            err = enum_devices(path, domain, bus, dev, func, lev+1);
+            err = enum_devices(pci_port, cwd_port, path, domain, bus, dev, 
func, lev+1);
             if (err && err != EPERM && err != EACCES) {
-                if (closedir(dir) < 0)
+                if (closedir_wrapper(dir) < 0)
                     return errno;
                 return err;
             }
@@ -370,12 +421,22 @@ enum_devices(const char *parent, int domain,
                 continue;
 
             /* We found an available virtual device, add it to our list */
-            snprintf(server, NAME_MAX, "%s/%04x/%02x/%02x/%01u/%s",
-                     _SERVERS_BUS_PCI, domain, bus, dev, func,
-                     entry->d_name);
-            device_port = file_name_lookup(server, 0, 0);
+            if (pci_port == MACH_PORT_NULL) {
+                snprintf(server, NAME_MAX, "%s/%04x/%02x/%02x/%01u/%s",
+                         _SERVERS_BUS_PCI, domain, bus, dev, func,
+                         entry->d_name);
+                device_port = file_name_lookup(server, 0, 0);
+            } else {
+                snprintf(server, NAME_MAX, "./%04x/%02x/%02x/%01u/%s",
+                         domain, bus, dev, func,
+                         entry->d_name);
+                device_port = file_name_lookup_under(pci_port, server, O_RDWR, 
0);
+                mach_print("pciaccess(hurd): Found ");
+                mach_print(server);
+                mach_print("\n");
+            }
             if (device_port == MACH_PORT_NULL) {
-                closedir(dir);
+                closedir_wrapper(dir);
                 return errno;
             }
 
@@ -383,12 +444,12 @@ enum_devices(const char *parent, int domain,
             err = pciclient_cfg_read(device_port, PCI_VENDOR_ID, (char*)&reg,
                                      &toread);
             if (err) {
-                if (closedir(dir) < 0)
+                if (closedir_wrapper(dir) < 0)
                     return errno;
                 return err;
             }
             if (toread != sizeof(reg)) {
-                if (closedir(dir) < 0)
+                if (closedir_wrapper(dir) < 0)
                     return errno;
                 return -1;
             }
@@ -396,7 +457,7 @@ enum_devices(const char *parent, int domain,
             devices = realloc(pci_sys->devices, (pci_sys->num_devices + 1)
                               * sizeof(struct pci_device_private));
             if (!devices) {
-                if (closedir(dir) < 0)
+                if (closedir_wrapper(dir) < 0)
                     return errno;
                 return ENOMEM;
             }
@@ -415,12 +476,12 @@ enum_devices(const char *parent, int domain,
             err = pciclient_cfg_read(device_port, PCI_CLASS, (char*)&reg,
                                      &toread);
             if (err) {
-                if (closedir(dir) < 0)
+                if (closedir_wrapper(dir) < 0)
                     return errno;
                 return err;
             }
             if (toread != sizeof(reg)) {
-                if (closedir(dir) < 0)
+                if (closedir_wrapper(dir) < 0)
                     return errno;
                 return -1;
             }
@@ -432,12 +493,12 @@ enum_devices(const char *parent, int domain,
             err = pciclient_cfg_read(device_port, PCI_SUB_VENDOR_ID,
                                      (char*)&reg, &toread);
             if (err) {
-                if (closedir(dir) < 0)
+                if (closedir_wrapper(dir) < 0)
                     return errno;
                 return err;
             }
             if (toread != sizeof(reg)) {
-                if (closedir(dir) < 0)
+                if (closedir_wrapper(dir) < 0)
                     return errno;
                 return -1;
             }
@@ -452,7 +513,7 @@ enum_devices(const char *parent, int domain,
         }
     }
 
-    if (closedir(dir) < 0)
+    if (closedir_wrapper(dir) < 0)
         return errno;
 
     return 0;
@@ -489,6 +550,8 @@ pci_system_hurd_create(void)
 {
     int err;
     struct pci_system_hurd *pci_sys_hurd;
+    mach_port_t device_master;
+    mach_port_t root, pci_server_port = MACH_PORT_NULL;
 
     if (&netfs_server_name && netfs_server_name
         && !strcmp(netfs_server_name, "pci-arbiter")) {
@@ -513,7 +576,15 @@ pci_system_hurd_create(void)
     pci_sys->methods = &hurd_pci_methods;
 
     pci_sys->num_devices = 0;
-    err = enum_devices(_SERVERS_BUS_PCI, -1, -1, -1, -1, LEVEL_DOMAIN);
+
+    if (! get_privileged_ports (NULL, &device_master) && (device_master != 
MACH_PORT_NULL)) {
+        device_open (device_master, D_READ|D_WRITE, "pci", &pci_server_port);
+        root = file_name_lookup_under (pci_server_port, ".", O_DIRECTORY | 
O_RDWR | O_EXEC, 0);
+        err = enum_devices(pci_server_port, root, ".", -1, -1, -1, -1, 
LEVEL_DOMAIN);
+    } else {
+        err = enum_devices(MACH_PORT_NULL, MACH_PORT_NULL, _SERVERS_BUS_PCI, 
-1, -1, -1, -1, LEVEL_DOMAIN);
+    }
+
     if (err) {
       /* There was an error, but we don't know which devices have been
        * initialized correctly, so call cleanup to free whatever is allocated 
*/
-- 
2.30.0