diff options
| author | Stefan Haberland <stefan.haberland@de.ibm.com> | 2016-03-18 09:42:13 +0100 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2016-04-15 18:16:37 +0200 |
| commit | 5a3b7b112884f80ff19b18028fabeb4f9c035518 (patch) | |
| tree | b1b743c481c829d26fdb97043f446f9f0d682b4f /drivers/s390/block/dasd.c | |
| parent | 2fd92273646abad21766ddfbfa00b6f927362308 (diff) | |
s390/dasd: add query host access to volume support
With this feature, applications can query if a DASD volume is online
to another operating system instances by checking the online status of
all attached hosts from the storage server.
Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'drivers/s390/block/dasd.c')
| -rw-r--r-- | drivers/s390/block/dasd.c | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c index c78db05e75b1..4adb6d14d562 100644 --- a/drivers/s390/block/dasd.c +++ b/drivers/s390/block/dasd.c @@ -75,6 +75,8 @@ static void dasd_block_timeout(unsigned long); static void __dasd_process_erp(struct dasd_device *, struct dasd_ccw_req *); static void dasd_profile_init(struct dasd_profile *, struct dentry *); static void dasd_profile_exit(struct dasd_profile *); +static void dasd_hosts_init(struct dentry *, struct dasd_device *); +static void dasd_hosts_exit(struct dasd_device *); /* * SECTION: Operations on the device structure. @@ -267,6 +269,7 @@ static int dasd_state_known_to_basic(struct dasd_device *device) dasd_debugfs_setup(dev_name(&device->cdev->dev), dasd_debugfs_root_entry); dasd_profile_init(&device->profile, device->debugfs_dentry); + dasd_hosts_init(device->debugfs_dentry, device); /* register 'device' debug area, used for all DBF_DEV_XXX calls */ device->debug_area = debug_register(dev_name(&device->cdev->dev), 4, 1, @@ -304,6 +307,7 @@ static int dasd_state_basic_to_known(struct dasd_device *device) return rc; dasd_device_clear_timer(device); dasd_profile_exit(&device->profile); + dasd_hosts_exit(device); debugfs_remove(device->debugfs_dentry); DBF_DEV_EVENT(DBF_EMERG, device, "%p debug area deleted", device); if (device->debug_area != NULL) { @@ -1150,6 +1154,58 @@ int dasd_profile_on(struct dasd_profile *profile) #endif /* CONFIG_DASD_PROFILE */ +static int dasd_hosts_show(struct seq_file *m, void *v) +{ + struct dasd_device *device; + int rc = -EOPNOTSUPP; + + device = m->private; + dasd_get_device(device); + + if (device->discipline->hosts_print) + rc = device->discipline->hosts_print(device, m); + + dasd_put_device(device); + return rc; +} + +static int dasd_hosts_open(struct inode *inode, struct file *file) +{ + struct dasd_device *device = inode->i_private; + + return single_open(file, dasd_hosts_show, device); +} + +static const struct file_operations dasd_hosts_fops = { + .owner = THIS_MODULE, + .open = dasd_hosts_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static void dasd_hosts_exit(struct dasd_device *device) +{ + debugfs_remove(device->hosts_dentry); + device->hosts_dentry = NULL; +} + +static void dasd_hosts_init(struct dentry *base_dentry, + struct dasd_device *device) +{ + struct dentry *pde; + umode_t mode; + + if (!base_dentry) + return; + + mode = S_IRUSR | S_IFREG; + pde = debugfs_create_file("host_access_list", mode, base_dentry, + device, &dasd_hosts_fops); + if (pde && !IS_ERR(pde)) + device->hosts_dentry = pde; +} + /* * Allocate memory for a channel program with 'cplength' channel * command words and 'datasize' additional space. There are two |