From 9de5d31f93dab36cfb451e9ad724d47311b54424 Mon Sep 17 00:00:00 2001 From: Jeremy Kerr Date: Fri, 29 Nov 2013 10:47:10 +0800 Subject: [PATCH] discover: Fix CDROM handling Currently, we don't handle CDROM devices well; we'll try to mount on boot, and not detect any media changes. Also, the default rules shipping with udev will put the CDROM tray into a locked state, blocking eject from working. This change adds a set of cdrom utility functions, which the udev code can use to properly initialise cdrom devices and handle eject and media change requests. Signed-off-by: Jeremy Kerr --- discover/Makefile.am | 2 ++ discover/cdrom.c | 81 ++++++++++++++++++++++++++++++++++++++++++++ discover/cdrom.h | 9 +++++ discover/udev.c | 81 +++++++++++++++++++++++++++++++++++++++++++- 4 files changed, 172 insertions(+), 1 deletion(-) create mode 100644 discover/cdrom.c create mode 100644 discover/cdrom.h diff --git a/discover/Makefile.am b/discover/Makefile.am index 2a7885d..84c0436 100644 --- a/discover/Makefile.am +++ b/discover/Makefile.am @@ -32,6 +32,8 @@ sbin_PROGRAMS = pb-discover pb_discover_SOURCES = \ boot.c \ boot.h \ + cdrom.c \ + cdrom.h \ device-handler.c \ device-handler.h \ discover-server.c \ diff --git a/discover/cdrom.c b/discover/cdrom.c new file mode 100644 index 0000000..0e88301 --- /dev/null +++ b/discover/cdrom.c @@ -0,0 +1,81 @@ +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +#include "cdrom.h" + +static int cdrom_open(const char *devpath, const char *loc) +{ + int fd; + + fd = open(devpath, O_RDONLY | O_NONBLOCK); + if (fd < 0) + pb_log("%s: can't open %s: %s\n", loc, devpath, + strerror(errno)); + + return fd; +} + +void cdrom_init(const char *devpath) +{ + int fd, rc; + + fd = cdrom_open(devpath, __func__); + if (fd < 0) + return; + + /* We disable autoclose so that any attempted mount() operation doesn't + * close the tray, and disable CDO_LOCK to prevent the lock status + * changing on open()/close() + */ + rc = ioctl(fd, CDROM_CLEAR_OPTIONS, CDO_LOCK | CDO_AUTO_CLOSE); + if (rc < 0) + pb_debug("%s: CLEAR CDO_LOCK|CDO_AUTO_CLOSE failed: %s\n", + __func__, strerror(errno)); + + close(fd); +} + +bool cdrom_media_present(const char *devpath) +{ + int fd, rc; + + fd = cdrom_open(devpath, __func__); + if (fd < 0) + return false; + + rc = ioctl(fd, CDROM_DRIVE_STATUS, CDSL_CURRENT); + + close(fd); + + return rc == CDS_DISC_OK; +} + +void cdrom_eject(const char *devpath) +{ + int fd, rc; + + fd = cdrom_open(devpath, __func__); + if (fd < 0) + return; + + /* unlock cdrom device */ + rc = ioctl(fd, CDROM_LOCKDOOR, 0); + if (rc < 0) + pb_log("%s: CDROM_LOCKDOOR(unlock) failed: %s\n", + __func__, strerror(errno)); + + rc = ioctl(fd, CDROMEJECT, 0); + if (rc < 0) + pb_log("%s: CDROM_EJECT failed: %s\n", + __func__, strerror(errno)); + close(fd); +} + diff --git a/discover/cdrom.h b/discover/cdrom.h new file mode 100644 index 0000000..2e9de06 --- /dev/null +++ b/discover/cdrom.h @@ -0,0 +1,9 @@ +#ifndef CDROM_H +#define CDROM_H + +void cdrom_init(const char *devpath); +void cdrom_eject(const char *devpath); +bool cdrom_media_present(const char *devpath); + +#endif /* CDROM_H */ + diff --git a/discover/udev.c b/discover/udev.c index 5aa2898..80029d6 100644 --- a/discover/udev.c +++ b/discover/udev.c @@ -22,6 +22,7 @@ #include "udev.h" #include "pb-discover.h" #include "device-handler.h" +#include "cdrom.h" struct pb_udev { struct udev *udev; @@ -64,7 +65,9 @@ static int udev_handle_dev_add(struct pb_udev *udev, struct udev_device *dev) const char *serial; const char *path; const char *name; + const char *node; const char *prop; + bool cdrom; name = udev_device_get_sysname(dev); if (!name) { @@ -83,6 +86,7 @@ static int udev_handle_dev_add(struct pb_udev *udev, struct udev_device *dev) return 0; } + node = udev_device_get_devnode(dev); path = udev_device_get_devpath(dev); if (path && (strstr(path, "virtual/block/loop") || strstr(path, "virtual/block/ram"))) { @@ -90,6 +94,17 @@ static int udev_handle_dev_add(struct pb_udev *udev, struct udev_device *dev) return 0; } + cdrom = node && !!udev_device_get_property_value(dev, "ID_CDROM"); + if (cdrom) { + /* CDROMs require a little initialisation, to get + * petitboot-compatible tray behaviour */ + cdrom_init(node); + if (!cdrom_media_present(node)) { + pb_debug("SKIP: %s: no media present\n", name); + return 0; + } + } + /* We have enough info to create the device and start discovery */ ddev = device_lookup_by_id(udev->handler, name); if (ddev) { @@ -105,7 +120,7 @@ static int udev_handle_dev_add(struct pb_udev *udev, struct udev_device *dev) ddev = discover_device_create(udev->handler, name); - ddev->device_path = talloc_strdup(ddev, udev_device_get_devnode(dev)); + ddev->device_path = talloc_strdup(ddev, node); prop = udev_device_get_property_value(dev, "ID_FS_UUID"); if (prop) @@ -141,16 +156,80 @@ static int udev_handle_dev_remove(struct pb_udev *udev, struct udev_device *dev) return 0; } + +static int udev_handle_dev_change(struct pb_udev *udev, struct udev_device *dev) +{ + struct discover_device *ddev; + const char *name, *node; + + name = udev_device_get_sysname(dev); + node = udev_device_get_devnode(dev); + + /* we're only interested in CDROM change events at present */ + if (!udev_device_get_property_value(dev, "ID_CDROM")) + return 0; + + /* handle CDROM eject requests */ + if (udev_device_get_property_value(dev, "DISK_EJECT_REQUEST")) { + bool eject = false; + + pb_debug("udev: eject request\n"); + + /* If the device is mounted, cdrom_id's own eject request may + * have failed. So, we'll need to do our own here. + */ + ddev = device_lookup_by_id(udev->handler, name); + if (ddev) { + eject = ddev->mounted; + udev_handle_dev_remove(udev, dev); + } + + if (eject) + cdrom_eject(node); + + return 0; + } + + if (udev_device_get_property_value(dev, "DISK_MEDIA_CHANGE")) { + if (cdrom_media_present(node)) + return udev_handle_dev_add(udev, dev); + else + return udev_handle_dev_remove(udev, dev); + } + + return 0; +} + static int udev_handle_dev_action(struct udev_device *dev, const char *action) { struct pb_udev *udev = udev_get_userdata(udev_device_get_udev(dev)); +#ifdef DEBUG + { + struct udev_list_entry *list; + const char *name; + + list = udev_device_get_properties_list_entry(dev); + name = udev_device_get_sysname(dev); + + pb_debug("%s: action %s, device %s\n", __func__, action, name); + pb_debug("%s properties:\n", __func__); + + for (; list; list = udev_list_entry_get_next(list)) + pb_log("\t%-20s: %s\n", udev_list_entry_get_name(list), + udev_list_entry_get_value(list)); + } while (0); +#endif + if (!strcmp(action, "add")) return udev_handle_dev_add(udev, dev); else if (!strcmp(action, "remove")) return udev_handle_dev_remove(udev, dev); + else if (!strcmp(action, "change")) + return udev_handle_dev_change(udev, dev); + return 0; } -- 2.39.2