diff options
Diffstat (limited to 'drivers/dsp/syslink/multicore_ipc/nameserver.c')
-rw-r--r-- | drivers/dsp/syslink/multicore_ipc/nameserver.c | 1530 |
1 files changed, 1530 insertions, 0 deletions
diff --git a/drivers/dsp/syslink/multicore_ipc/nameserver.c b/drivers/dsp/syslink/multicore_ipc/nameserver.c new file mode 100644 index 00000000000..c164b78630b --- /dev/null +++ b/drivers/dsp/syslink/multicore_ipc/nameserver.c @@ -0,0 +1,1530 @@ +/* + * nameserver.c + * + * The nameserver module manages local name/value pairs that + * enables an application and other modules to store and retrieve + * values based on a name. + * + * Copyright (C) 2008-2009 Texas Instruments, Inc. + * + * This package is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * THIS PACKAGE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED + * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR + * PURPOSE. + */ +#include <linux/module.h> +#include <linux/types.h> +#include <linux/string.h> +#include <linux/list.h> +#include <linux/mutex.h> +#include <linux/slab.h> +#include <syslink/atomic_linux.h> + +#include <nameserver.h> +#include <multiproc.h> +#include <nameserver_remote.h> + +#define NS_MAX_NAME_LEN 32 +#define NS_MAX_RUNTIME_ENTRY (~0) +#define NS_MAX_VALUE_LEN 4 + +/* + * The dynamic name/value table looks like the following. This approach allows + * each instance table to have different value and different name lengths. + * The names block is allocated on the create. The size of that block is + * (max_runtime_entries * max_name_en). That block is sliced and diced up and + * given to each table entry. + * The same thing is done for the values block. + * + * names table values + * ------------- ------------- ------------- + * | |<-\ | elem | /----->| | + * | | \-------| name | / | | + * | | | value |-/ | | + * | | | len | | | + * | |<-\ |-----------| | | + * | | \ | elem | | | + * | | \------| name | /------>| | + * | | | value |-/ | | + * ------------- | len | | | + * ------------- | | + * | | + * | | + * ------------- + * + * There is an optimization for small values (e.g. <= sizeof(UInt32). + * In this case, there is no values block allocated. Instead the value + * field is used directly. This optimization occurs and is managed when + * obj->max_value_len <= sizeof(Us3232). + * + * The static create is a little different. The static entries point directly + * to a name string (and value). Since it points directly to static items, + * this entries cannot be removed. + * If max_runtime_entries is non-zero, a names and values block is created. + * Here is an example of a table with 1 static entry and 2 dynamic entries + * + * ------------ + * this entries cannot be removed. + * If max_runtime_entries is non-zero, a names and values block is created. + * Here is an example of a table with 1 static entry and 2 dynamic entries + * + * ------------ + * | elem | + * "myName" <-----------| name |----------> someValue + * | value | + * names | len | values + * ------------- ------------- ------------- + * | |<-\ | elem | /----->| | + * | | \-------| name | / | | + * | | | value |-/ | | + * | | | len | | | + * | |<-\ |-----------| | | + * | | \ | elem | | | + * | | \------| name | /------>| | + * | | | value |-/ | | + * ------------- | len | | | + * ------------- | | + * | | + * | | + * ------------- + * + * NameServerD uses a freeList and namelist to maintain the empty + * and filled-in entries. So when a name/value pair is added, an entry + * is pulled off the freeList, filled-in and placed on the namelist. + * The reverse happens on a remove. + * + * For static adds, the entries are placed on the namelist statically. + * + * For dynamic creates, the freeList is populated in postInt and there are no + * entries placed on the namelist (this happens when the add is called). + * + */ + +/* Macro to make a correct module magic number with refCount */ +#define NAMESERVER_MAKE_MAGICSTAMP(x) ((NAMESERVER_MODULEID << 12u) | (x)) + +/* + * A name/value table entry + */ +struct nameserver_table_entry { + struct list_head elem; /* List element */ + u32 hash; /* Hash value */ + char *name; /* Name portion of name/value pair */ + u32 len; /* Length of the value field. */ + void *buf; /* Value portion of name/value entry */ + bool collide; /* Does the hash collides? */ + struct nameserver_table_entry *next; /* Pointer to the next entry, + used incase of collision only */ +}; + +/* + * A nameserver instance object + */ +struct nameserver_object { + struct list_head elem; + char *name; /* Name of the instance */ + struct list_head name_list; /* Filled entries list */ + struct mutex *gate_handle; /* Gate for critical regions */ + struct nameserver_params params; /* The parameter structure */ + u32 count; /* Counter for entries */ +}; + + +/* nameserver module state object */ +struct nameserver_module_object { + struct list_head obj_list; /* List holding created objects */ + struct mutex *mod_gate_handle; /* Handle to module gate */ + struct nameserver_remote_object **remote_handle_list; + /* List of Remote driver handles for processors */ + atomic_t ref_count; /* Reference count */ + struct nameserver_params def_inst_params; + /* Default instance paramters */ + struct nameserver_config def_cfg; /* Default module configuration */ + struct nameserver_config cfg; /* Module configuration */ + +}; + +/* + * Variable for holding state of the nameserver module. + */ +static struct nameserver_module_object nameserver_state = { + .def_cfg.reserved = 0x0, + .def_inst_params.max_runtime_entries = 0u, + .def_inst_params.table_heap = NULL, + .def_inst_params.check_existing = true, + .def_inst_params.max_value_len = 0u, + .def_inst_params.max_name_len = 16u, + .mod_gate_handle = NULL, + .remote_handle_list = NULL, +}; + +/* + * Pointer to the SharedRegion module state + */ +static struct nameserver_module_object *nameserver_module = &(nameserver_state); + +/* + * Lookup table for CRC calculation. + */ +static const u32 nameserver_crc_table[256u] = { + 0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f, + 0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, + 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2, + 0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7, + 0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9, + 0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172, + 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c, + 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59, + 0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, + 0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, + 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106, + 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433, + 0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, + 0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, + 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950, + 0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65, + 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7, + 0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0, + 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa, + 0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f, + 0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81, + 0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a, + 0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84, + 0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1, + 0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb, + 0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc, + 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e, + 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b, + 0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, + 0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, + 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28, + 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d, + 0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f, + 0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, + 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242, + 0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777, + 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69, + 0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2, + 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc, + 0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9, + 0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693, + 0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94, + 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d, +}; + +/* Function to calculate hash for a string */ +static u32 _nameserver_string_hash(const char *string); + +#if 0 +/* This will return true if the entry is found in the table */ +static bool _nameserver_is_entry_found(const char *name, u32 hash, + struct list_head *list, + struct nameserver_table_entry **entry); +#endif + +/* This will return true if the hash is found in the table */ +static bool _nameserver_is_hash_found(const char *name, u32 hash, + struct list_head *list, + struct nameserver_table_entry **entry); + +/* This will return true if entry is found in the hash collide list */ +static bool _nameserver_check_for_entry(const char *name, + struct nameserver_table_entry **entry); + +/* Function to get the default configuration for the NameServer module. */ +void nameserver_get_config(struct nameserver_config *cfg) +{ + s32 retval = 0; + + if (WARN_ON(cfg == NULL)) { + retval = -EINVAL; + goto exit; + } + + if (atomic_cmpmask_and_lt(&(nameserver_module->ref_count), + NAMESERVER_MAKE_MAGICSTAMP(0), + NAMESERVER_MAKE_MAGICSTAMP(1)) == true) { + /* (If setup has not yet been called) */ + memcpy(cfg, &nameserver_module->def_cfg, + sizeof(struct nameserver_config)); + } else { + memcpy(cfg, &nameserver_module->cfg, + sizeof(struct nameserver_config)); + } + +exit: + if (retval < 0) + pr_err("nameserver_get_config failed! retval = 0x%x", retval); + return; +} +EXPORT_SYMBOL(nameserver_get_config); + +/* This will setup the nameserver module */ +int nameserver_setup(void) +{ + struct nameserver_remote_object **list = NULL; + s32 retval = 0; + u16 nr_procs = 0; + + /* This sets the ref_count variable if not initialized, upper 16 bits is + * written with module Id to ensure correctness of refCount variable + */ + atomic_cmpmask_and_set(&nameserver_module->ref_count, + NAMESERVER_MAKE_MAGICSTAMP(0), + NAMESERVER_MAKE_MAGICSTAMP(0)); + + if (atomic_inc_return(&nameserver_module->ref_count) + != NAMESERVER_MAKE_MAGICSTAMP(1)) { + return 1; + } + + INIT_LIST_HEAD(&nameserver_state.obj_list), + + nameserver_module->mod_gate_handle = kmalloc(sizeof(struct mutex), + GFP_KERNEL); + if (nameserver_module->mod_gate_handle == NULL) { + retval = -ENOMEM; + goto exit; + } + /* mutex is initialized with state = UNLOCKED */ + mutex_init(nameserver_module->mod_gate_handle); + + nr_procs = multiproc_get_num_processors(); + list = kmalloc(nr_procs * sizeof(struct nameserver_remote_object *), + GFP_KERNEL); + if (list == NULL) { + retval = -ENOMEM; + goto remote_alloc_fail; + } + memset(list, 0, nr_procs * sizeof(struct nameserver_remote_object *)); + nameserver_module->remote_handle_list = list; + + return 0; + +remote_alloc_fail: + kfree(nameserver_module->mod_gate_handle); +exit: + pr_err("nameserver_setup failed, retval: %x\n", retval); + return retval; +} +EXPORT_SYMBOL(nameserver_setup); + +/* This will destroy the nameserver module */ +int nameserver_destroy(void) +{ + s32 retval = 0; + struct mutex *lock = NULL; + + if (WARN_ON(unlikely(atomic_cmpmask_and_lt( + &(nameserver_module->ref_count), + NAMESERVER_MAKE_MAGICSTAMP(0), + NAMESERVER_MAKE_MAGICSTAMP(1)) == true))) { + retval = -ENODEV; + goto exit; + } + + if (!(atomic_dec_return(&nameserver_module->ref_count) + == NAMESERVER_MAKE_MAGICSTAMP(0))) { + retval = 1; + goto exit; + } + + if (WARN_ON(nameserver_module->mod_gate_handle == NULL)) { + retval = -ENODEV; + goto exit; + } + + /* If a nameserver instance exist, do not proceed */ + if (!list_empty(&nameserver_module->obj_list)) { + retval = -EBUSY; + goto exit; + } + + retval = mutex_lock_interruptible(nameserver_module->mod_gate_handle); + if (retval) + goto exit; + + lock = nameserver_module->mod_gate_handle; + nameserver_module->mod_gate_handle = NULL; + mutex_unlock(lock); + kfree(lock); + kfree(nameserver_module->remote_handle_list); + nameserver_module->remote_handle_list = NULL; + return 0; + +exit: + if (retval < 0) + pr_err("nameserver_destroy failed, retval: %x\n", retval); + return retval; +} +EXPORT_SYMBOL(nameserver_destroy); + +/* Initialize this config-params structure with supplier-specified + * defaults before instance creation. */ +void nameserver_params_init(struct nameserver_params *params) +{ + s32 retval = 0; + + if (WARN_ON(unlikely(atomic_cmpmask_and_lt( + &(nameserver_module->ref_count), + NAMESERVER_MAKE_MAGICSTAMP(0), + NAMESERVER_MAKE_MAGICSTAMP(1)) == true))) { + retval = -ENODEV; + goto exit; + } + if (WARN_ON(unlikely(params == NULL))) { + retval = -EINVAL; + goto exit; + } + + memcpy(params, &nameserver_module->def_inst_params, + sizeof(struct nameserver_params)); + +exit: + if (retval < 0) + pr_err("nameserver_params_init failed! status = 0x%x", retval); + return; +} +EXPORT_SYMBOL(nameserver_params_init); + +/* This will create a name server instance */ +void *nameserver_create(const char *name, + const struct nameserver_params *params) +{ + struct nameserver_object *new_obj = NULL; + u32 name_len; + s32 retval = 0; + + if (WARN_ON(unlikely(atomic_cmpmask_and_lt( + &(nameserver_module->ref_count), + NAMESERVER_MAKE_MAGICSTAMP(0), + NAMESERVER_MAKE_MAGICSTAMP(1)) == true))) { + retval = -ENODEV; + goto exit; + } + if (WARN_ON(unlikely(params == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(name == NULL))) { + retval = -EINVAL; + goto exit; + } + + name_len = strlen(name) + 1; + if (name_len > params->max_name_len) { + retval = -E2BIG; + goto exit; + } + + retval = mutex_lock_interruptible(nameserver_module->mod_gate_handle); + if (retval) + goto exit; + + /* check if the name is already registered or not */ + new_obj = nameserver_get_handle(name); + if (new_obj != NULL) { + retval = -EEXIST; + goto error_handle; + } + + new_obj = kmalloc(sizeof(struct nameserver_object), GFP_KERNEL); + if (new_obj == NULL) { + retval = -ENOMEM; + goto error; + } + + new_obj->name = kmalloc(name_len, GFP_ATOMIC); + if (new_obj->name == NULL) { + retval = -ENOMEM; + goto error; + } + + strncpy(new_obj->name, name, name_len); + memcpy(&new_obj->params, params, sizeof(struct nameserver_params)); + if (params->max_value_len < sizeof(u32)) + new_obj->params.max_value_len = sizeof(u32); + else + new_obj->params.max_value_len = params->max_value_len; + + new_obj->gate_handle = kmalloc(sizeof(struct mutex), GFP_KERNEL); + if (new_obj->gate_handle == NULL) { + retval = -ENOMEM; + goto error_mutex; + } + + mutex_init(new_obj->gate_handle); + new_obj->count = 0; + /* Put in the nameserver instance to local list */ + INIT_LIST_HEAD(&new_obj->name_list); + INIT_LIST_HEAD(&new_obj->elem); + list_add(&new_obj->elem, &nameserver_module->obj_list); + mutex_unlock(nameserver_module->mod_gate_handle); + return (void *)new_obj; + +error_mutex: + kfree(new_obj->name); +error: + kfree(new_obj); +error_handle: + mutex_unlock(nameserver_module->mod_gate_handle); +exit: + pr_err("nameserver_create failed retval:%x\n", retval); + return NULL; +} +EXPORT_SYMBOL(nameserver_create); + +/* Function to construct a name server. */ +void nameserver_construct(void *handle, const char *name, + const struct nameserver_params *params) +{ + struct nameserver_object *obj = NULL; + u32 name_len = 0; + s32 retval = 0; + + if (WARN_ON(unlikely(atomic_cmpmask_and_lt( + &(nameserver_module->ref_count), + NAMESERVER_MAKE_MAGICSTAMP(0), + NAMESERVER_MAKE_MAGICSTAMP(1)) == true))) { + retval = -ENODEV; + goto exit; + } + if (WARN_ON(unlikely(handle == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(params == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(name == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(params->table_heap == NULL))) { + retval = -EINVAL; + goto exit; + } + /* check if the name is already registered or not */ + if (nameserver_get_handle(name)) { + retval = -EEXIST; /* NameServer_E_ALREADYEXISTS */ + goto exit; + } + name_len = strlen(name) + 1; + if (name_len > params->max_name_len) { + retval = -E2BIG; + goto exit; + } + + obj = (struct nameserver_object *) handle; + /* Allocate memory for the name */ + obj->name = kmalloc(name_len, GFP_ATOMIC); + if (obj->name == NULL) { + retval = -ENOMEM; + goto exit; + } + + /* Copy the name */ + strncpy(obj->name, name, strlen(name) + 1u); + /* Copy the params */ + memcpy((void *) &obj->params, (void *) params, + sizeof(struct nameserver_params)); + + if (params->max_value_len < sizeof(u32)) + obj->params.max_value_len = sizeof(u32); + else + obj->params.max_value_len = params->max_value_len; + + /* Construct the list */ + INIT_LIST_HEAD(&obj->name_list); + + obj->gate_handle = kmalloc(sizeof(struct mutex), GFP_KERNEL); + if (obj->gate_handle == NULL) { + retval = -ENOMEM; + goto exit; + } + mutex_init(obj->gate_handle); + + /* Initialize the count */ + obj->count = 0u; + + /* Put in the local list */ + retval = mutex_lock_interruptible(nameserver_module->mod_gate_handle); + if (retval) + goto exit; + INIT_LIST_HEAD(&obj->elem); + list_add(&obj->elem, &nameserver_module->obj_list); + mutex_unlock(nameserver_module->mod_gate_handle); + +exit: + if (retval < 0) + pr_err("nameserver_construct failed! retval = 0x%x", retval); + return; +} + +/* This will delete a name server instance */ +int nameserver_delete(void **handle) +{ + struct nameserver_object *temp_obj = NULL; + struct mutex *gate_handle = NULL; + s32 retval = 0; + + if (WARN_ON(unlikely(atomic_cmpmask_and_lt( + &(nameserver_module->ref_count), + NAMESERVER_MAKE_MAGICSTAMP(0), + NAMESERVER_MAKE_MAGICSTAMP(1)) == true))) { + retval = -ENODEV; + goto exit; + } + if (WARN_ON(unlikely(handle == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(*handle == NULL))) { + retval = -EINVAL; + goto exit; + } + + temp_obj = (struct nameserver_object *) (*handle); + if (WARN_ON(unlikely((temp_obj->name == NULL) && + (nameserver_get_handle(temp_obj->name) == NULL)))) { + retval = -EINVAL; + goto exit; + } + + gate_handle = temp_obj->gate_handle; + retval = mutex_lock_interruptible(gate_handle); + if (retval) + goto exit; + + /* Do not proceed if an entry in the in the table */ + if (temp_obj->count != 0) { + retval = -EBUSY; + goto error; + } + + retval = mutex_lock_interruptible(nameserver_module->mod_gate_handle); + if (retval) + goto error; + list_del(&temp_obj->elem); + mutex_unlock(nameserver_module->mod_gate_handle); + + /* free the memory allocated for instance name */ + kfree(temp_obj->name); + temp_obj->name = NULL; + + /* Free the memory used for handle */ + INIT_LIST_HEAD(&temp_obj->name_list); + kfree(temp_obj); + *handle = NULL; + mutex_unlock(gate_handle); + kfree(gate_handle); + return 0; + +error: + mutex_unlock(gate_handle); +exit: + pr_err("nameserver_delete failed retval:%x\n", retval); + return retval; +} +EXPORT_SYMBOL(nameserver_delete); + +/* Function to destroy a name server. */ +void nameserver_destruct(void *handle) +{ + struct nameserver_object *obj = NULL; + struct mutex *gate_handle = NULL; + s32 retval = 0; + + if (WARN_ON(unlikely(atomic_cmpmask_and_lt( + &(nameserver_module->ref_count), + NAMESERVER_MAKE_MAGICSTAMP(0), + NAMESERVER_MAKE_MAGICSTAMP(1)) == true))) { + retval = -ENODEV; + goto exit; + } + if (WARN_ON(unlikely(handle == NULL))) { + retval = -EINVAL; + goto exit; + } + + obj = (struct nameserver_object *) handle; + if (nameserver_get_handle(obj->name) == NULL) { + retval = -EINVAL; + goto exit; + } + + /* enter the critical section */ + gate_handle = obj->gate_handle; + retval = mutex_lock_interruptible(gate_handle); + if (retval) + goto exit; + /* Do not proceed if an entry in the in the table */ + if (obj->count != 0) { + retval = -EBUSY; + goto error; + } + + retval = mutex_lock_interruptible(nameserver_module->mod_gate_handle); + if (retval) + goto error; + list_del(&obj->elem); + mutex_unlock(nameserver_module->mod_gate_handle); + + /* free the memory allocated for the name */ + kfree(obj->name); + obj->name = NULL; + + /* Destruct the list */ + INIT_LIST_HEAD(&obj->name_list); + + /* Free the memory used for obj */ + memset(obj, 0, sizeof(struct nameserver_object)); + + /* leave the critical section */ + mutex_unlock(gate_handle); + kfree(gate_handle); + return; + +error: + /* leave the critical section */ + mutex_unlock(obj->gate_handle); + +exit: + pr_err("nameserver_destruct failed! status = 0x%x", retval); + return; +} + +/* This will add an entry into a nameserver instance */ +void *nameserver_add(void *handle, const char *name, + void *buf, u32 len) +{ + struct nameserver_table_entry *node = NULL; + struct nameserver_table_entry *new_node = NULL; + struct nameserver_object *temp_obj = NULL; + bool found = false; + bool exact_entry = false; + u32 hash; + u32 name_len; + s32 retval = 0; + + if (WARN_ON(unlikely(atomic_cmpmask_and_lt( + &(nameserver_module->ref_count), + NAMESERVER_MAKE_MAGICSTAMP(0), + NAMESERVER_MAKE_MAGICSTAMP(1)) == true))) { + retval = -ENODEV; + goto exit; + } + if (WARN_ON(unlikely(handle == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(name == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(buf == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(len == 0))) { + retval = -EINVAL; + goto exit; + } + + temp_obj = (struct nameserver_object *)handle; + retval = mutex_lock_interruptible(temp_obj->gate_handle); + if (retval) + goto exit; + if (temp_obj->count >= temp_obj->params.max_runtime_entries) { + retval = -ENOSPC; + goto error; + } + + /* make the null char in to account */ + name_len = strlen(name) + 1; + if (name_len > temp_obj->params.max_name_len) { + retval = -E2BIG; + goto error; + } + + /* TODO : hash and collide ?? */ + hash = _nameserver_string_hash(name); + found = _nameserver_is_hash_found(name, hash, + &temp_obj->name_list, &node); + if (found == true) + exact_entry = _nameserver_check_for_entry(name, &node); + + if (exact_entry == true && temp_obj->params.check_existing == true) { + retval = -EEXIST; + goto error; + } + + new_node = kmalloc(sizeof(struct nameserver_table_entry), GFP_KERNEL); + if (new_node == NULL) { + retval = -ENOMEM; + goto error; + } + + new_node->hash = hash; + new_node->collide = found; + new_node->len = len; + new_node->next = NULL; + new_node->name = kmalloc(name_len, GFP_KERNEL); + if (new_node->name == NULL) { + retval = -ENOMEM; + goto error_name; + } + new_node->buf = kmalloc(len, GFP_KERNEL); + if (new_node->buf == NULL) { + retval = -ENOMEM; + goto error_buf; + } + + strncpy(new_node->name, name, name_len); + memcpy(new_node->buf, buf, len); + if (found == true) { + /* If hash is found, need to stitch the list to link the + * new node to the existing node with the same hash. */ + new_node->next = node->next; + node->next = new_node; + node->collide = found; + } else + list_add(&new_node->elem, &temp_obj->name_list); + temp_obj->count++; + mutex_unlock(temp_obj->gate_handle); + return new_node; + +error_buf: + kfree(new_node->name); +error_name: + kfree(new_node); +error: + mutex_unlock(temp_obj->gate_handle); +exit: + pr_err("nameserver_add failed status: %x\n", retval); + return NULL; +} +EXPORT_SYMBOL(nameserver_add); + +/* This will add a Uint32 value into a nameserver instance */ +void *nameserver_add_uint32(void *handle, const char *name, + u32 value) +{ + s32 retval = 0; + struct nameserver_table_entry *new_node = NULL; + + if (WARN_ON(unlikely(atomic_cmpmask_and_lt( + &(nameserver_module->ref_count), + NAMESERVER_MAKE_MAGICSTAMP(0), + NAMESERVER_MAKE_MAGICSTAMP(1)) == true))) { + retval = -ENODEV; + goto exit; + } + if (WARN_ON(unlikely(handle == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(name == NULL))) { + retval = -EINVAL; + goto exit; + } + + new_node = nameserver_add(handle, name, &value, sizeof(u32)); + +exit: + if (retval < 0 || new_node == NULL) { + pr_err("nameserver_add_uint32 failed! status = 0x%x " + "new_node = 0x%x", retval, (u32)new_node); + } + return new_node; +} +EXPORT_SYMBOL(nameserver_add_uint32); + +/* This will remove a name/value pair from a name server */ +int nameserver_remove(void *handle, const char *name) +{ + struct nameserver_object *temp_obj = NULL; + struct nameserver_table_entry *entry = NULL; + struct nameserver_table_entry *prev = NULL; + bool found = false; + u32 hash; + u32 name_len; + s32 retval = 0; + + if (WARN_ON(unlikely(atomic_cmpmask_and_lt( + &(nameserver_module->ref_count), + NAMESERVER_MAKE_MAGICSTAMP(0), + NAMESERVER_MAKE_MAGICSTAMP(1)) == true))) { + retval = -ENODEV; + goto exit; + } + if (WARN_ON(unlikely(handle == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(name == NULL))) { + retval = -EINVAL; + goto exit; + } + + temp_obj = (struct nameserver_object *)handle; + name_len = strlen(name) + 1; + if (name_len > temp_obj->params.max_name_len) { + retval = -E2BIG; + goto exit; + } + + retval = mutex_lock_interruptible(temp_obj->gate_handle); + if (retval) + goto exit; + + hash = _nameserver_string_hash(name); + found = _nameserver_is_hash_found(name, hash, + &temp_obj->name_list, &entry); + if (found == false) { + retval = -ENOENT; + goto error; + } + + if (entry->collide == true) { + if (strcmp(entry->name, name) == 0u) { + kfree(entry->buf); + kfree(entry->name); + entry->hash = entry->next->hash; + entry->name = entry->next->name; + entry->len = entry->next->len; + entry->buf = entry->next->buf; + entry->collide = entry->next->collide; + entry->next = entry->next->next; + kfree(entry->next); + temp_obj->count--; + } else { + found = false; + prev = entry; + entry = entry->next; + while (entry) { + if (strcmp(entry->name, name) == 0u) { + kfree(entry->buf); + kfree(entry->name); + prev->next = entry->next; + kfree(entry); + temp_obj->count--; + found = true; + break; + } + prev = entry; + entry = entry->next; + } + if (found == false) { + retval = -ENOENT; + goto error; + } + } + } else { + kfree(entry->buf); + kfree(entry->name); + list_del(&entry->elem); + kfree(entry); + temp_obj->count--; + } + + mutex_unlock(temp_obj->gate_handle); + return 0; + +error: + mutex_unlock(temp_obj->gate_handle); +exit: + pr_err("nameserver_remove failed status:%x\n", retval); + return retval; +} +EXPORT_SYMBOL(nameserver_remove); + +/* This will remove a name/value pair from a name server */ +int nameserver_remove_entry(void *nshandle, void *nsentry) +{ + struct nameserver_table_entry *node = NULL; + struct nameserver_object *obj = NULL; + s32 retval = 0; + + if (WARN_ON(unlikely(atomic_cmpmask_and_lt( + &(nameserver_module->ref_count), + NAMESERVER_MAKE_MAGICSTAMP(0), + NAMESERVER_MAKE_MAGICSTAMP(1)) == true))) { + retval = -ENODEV; + goto exit; + } + if (WARN_ON(unlikely(nshandle == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(nsentry == NULL))) { + retval = -EINVAL; + goto exit; + } + + obj = (struct nameserver_object *)nshandle; + node = (struct nameserver_table_entry *)nsentry; + retval = mutex_lock_interruptible(obj->gate_handle); + if (retval) + goto exit; + + kfree(node->buf); + kfree(node->name); + list_del(&node->elem); + kfree(node); + obj->count--; + mutex_unlock(obj->gate_handle); + return 0; + +exit: + pr_err("nameserver_remove_entry failed status:%x\n", retval); + return retval; +} +EXPORT_SYMBOL(nameserver_remove_entry); + + +/* This will retrieve the value portion of a name/value + * pair from local table */ +int nameserver_get_local(void *handle, const char *name, + void *value, u32 *len) +{ + struct nameserver_object *temp_obj = NULL; + struct nameserver_table_entry *entry = NULL; + bool found = false; + u32 hash; + u32 length = 0; + s32 retval = 0; + + if (WARN_ON(unlikely(atomic_cmpmask_and_lt( + &(nameserver_module->ref_count), + NAMESERVER_MAKE_MAGICSTAMP(0), + NAMESERVER_MAKE_MAGICSTAMP(1)) == true))) { + retval = -ENODEV; + goto exit; + } + if (WARN_ON(unlikely(handle == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(name == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(value == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(len == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(*len == 0))) { + retval = -EINVAL; + goto exit; + } + + length = *len; + temp_obj = (struct nameserver_object *)handle; + retval = mutex_lock_interruptible(temp_obj->gate_handle); + if (retval) + goto exit; + + hash = _nameserver_string_hash(name); + found = _nameserver_is_hash_found(name, hash, + &temp_obj->name_list, &entry); + if (found == false) { + retval = -ENOENT; + goto error; + } + + if (entry->collide == true) { + found = _nameserver_check_for_entry(name, &entry); + if (found == false) { + retval = -ENOENT; + goto error; + } + } + + if (entry->len >= length) { + memcpy(value, entry->buf, length); + *len = length; + } else { + memcpy(value, entry->buf, entry->len); + *len = entry->len; + } + +error: + mutex_unlock(temp_obj->gate_handle); + +exit: + if (retval < 0) + pr_err("nameserver_get_local entry not found!\n"); + return retval; +} +EXPORT_SYMBOL(nameserver_get_local); + +/* This will retrieve the value portion of a name/value + * pair from local table */ +int nameserver_get(void *handle, const char *name, + void *value, u32 *len, u16 proc_id[]) +{ + struct nameserver_object *temp_obj = NULL; + u16 max_proc_id; + u16 local_proc_id; + s32 retval = -ENOENT; + u32 i; + + if (WARN_ON(unlikely(atomic_cmpmask_and_lt( + &(nameserver_module->ref_count), + NAMESERVER_MAKE_MAGICSTAMP(0), + NAMESERVER_MAKE_MAGICSTAMP(1)) == true))) { + retval = -ENODEV; + goto exit; + } + if (WARN_ON(unlikely(handle == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(name == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(value == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(len == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(*len == 0))) { + retval = -EINVAL; + goto exit; + } + + temp_obj = (struct nameserver_object *)handle; + max_proc_id = multiproc_get_num_processors(); + local_proc_id = multiproc_self(); + if (proc_id == NULL) { + retval = nameserver_get_local(temp_obj, name, value, len); + if (retval == -ENOENT) { + for (i = 0; i < max_proc_id; i++) { + /* Skip current processor */ + if (i == local_proc_id) + continue; + + if (nameserver_module->remote_handle_list[i] \ + == NULL) + continue; + + retval = nameserver_remote_get( + nameserver_module-> + remote_handle_list[i], + temp_obj->name, name, value, + len, NULL); + if (retval >= 0 || ((retval < 0) && + (retval != -ENOENT))) + break; + } + } + goto exit; + } + + for (i = 0; i < max_proc_id; i++) { + /* Skip processor with invalid id */ + if (proc_id[i] == MULTIPROC_INVALIDID) + continue; + + if (i == local_proc_id) { + retval = nameserver_get_local(temp_obj, + name, value, len); + } else { + retval = nameserver_remote_get( + nameserver_module-> + remote_handle_list[proc_id[i]], + temp_obj->name, name, value, len, NULL); + } + if (retval >= 0 || ((retval < 0) && (retval != -ENOENT))) + break; + } + +exit: + if (retval < 0) + pr_err("nameserver_get failed: status=%x\n", retval); + return retval; +} +EXPORT_SYMBOL(nameserver_get); + +/* Gets a 32-bit value by name */ +int nameserver_get_uint32(void *handle, const char *name, void *value, + u16 proc_id[]) +{ + /* Initialize retval to not found */ + int retval = -ENOENT; + u32 len = sizeof(u32); + + if (WARN_ON(unlikely(atomic_cmpmask_and_lt( + &(nameserver_module->ref_count), + NAMESERVER_MAKE_MAGICSTAMP(0), + NAMESERVER_MAKE_MAGICSTAMP(1)) == true))) { + retval = -ENODEV; + goto exit; + } + if (WARN_ON(unlikely(handle == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(name == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(value == NULL))) { + retval = -EINVAL; + goto exit; + } + + retval = nameserver_get(handle, name, value, &len, proc_id); + +exit: + /* -ENOENT is a valid run-time failure. */ + if ((retval < 0) && (retval != -ENOENT)) + pr_err("nameserver_get_uint32 failed! status = 0x%x", retval); + return retval; +} +EXPORT_SYMBOL(nameserver_get_uint32); + +/* Gets a 32-bit value by name from the local table + * + * If the name is found, the 32-bit value is copied into the value + * argument and a success retval is returned. + * + * If the name is not found, zero is returned in len and the contents + * of value are not modified. Not finding a name is not considered + * an error. + * + * This function only searches the local name/value table. */ +int nameserver_get_local_uint32(void *handle, const char *name, void *value) +{ + int retval = 0; + u32 len = sizeof(u32); + + if (WARN_ON(unlikely(atomic_cmpmask_and_lt( + &(nameserver_module->ref_count), + NAMESERVER_MAKE_MAGICSTAMP(0), + NAMESERVER_MAKE_MAGICSTAMP(1)) == true))) { + retval = -ENODEV; + goto exit; + } + if (WARN_ON(unlikely(handle == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(name == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(value == NULL))) { + retval = -EINVAL; + goto exit; + } + + retval = nameserver_get_local(handle, name, value, &len); + +exit: + /* -ENOENT is a valid run-time failure. */ + if ((retval < 0) && (retval != -ENOENT)) { + pr_err("nameserver_get_local_uint32 failed! " + "status = 0x%x", retval); + } + return retval; +} +EXPORT_SYMBOL(nameserver_get_local_uint32); + +/* This will retrieve the value portion of a name/value + * pair from local table. Returns the number of characters that + * matched with an entry. So if "abc" was an entry and you called + * match with "abcd", this function will have the "abc" entry. + * The return would be 3 since three characters matched */ +int nameserver_match(void *handle, const char *name, u32 *value) +{ + struct nameserver_object *temp_obj = NULL; + struct nameserver_table_entry *node = NULL; + struct nameserver_table_entry *temp = NULL; + u32 len = 0; + u32 found_len = 0; + s32 retval = 0; + + if (WARN_ON(unlikely(atomic_cmpmask_and_lt( + &(nameserver_module->ref_count), + NAMESERVER_MAKE_MAGICSTAMP(0), + NAMESERVER_MAKE_MAGICSTAMP(1)) == true))) { + retval = -ENODEV; + goto exit; + } + if (WARN_ON(unlikely(handle == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(name == NULL))) { + retval = -EINVAL; + goto exit; + } + if (WARN_ON(unlikely(value == NULL))) { + retval = -EINVAL; + goto exit; + } + + temp_obj = (struct nameserver_object *)handle; + retval = mutex_lock_interruptible(temp_obj->gate_handle); + if (retval) + goto exit; + list_for_each_entry(node, &temp_obj->name_list, elem) { + temp = node; + while (temp) { + len = strlen(temp->name); + if (len > found_len) { + if (strncmp(temp->name, name, len) == 0u) { + *value = (u32)temp->buf; + found_len = len; + } + } + temp = temp->next; + } + } + mutex_unlock(temp_obj->gate_handle); + +exit: + if (retval < 0) + pr_err("nameserver_match failed status:%x\n", retval); + return found_len; +} +EXPORT_SYMBOL(nameserver_match); + +/* This will get the handle of a nameserver instance from name */ +void *nameserver_get_handle(const char *name) +{ + struct nameserver_object *obj = NULL; + bool found = false; + s32 retval = 0; + + if (WARN_ON(unlikely(atomic_cmpmask_and_lt( + &(nameserver_module->ref_count), + NAMESERVER_MAKE_MAGICSTAMP(0), + NAMESERVER_MAKE_MAGICSTAMP(1)) == true))) { + retval = -ENODEV; + goto exit; + } + if (WARN_ON(unlikely(name == NULL))) { + retval = -EINVAL; + goto exit; + } + + list_for_each_entry(obj, &nameserver_module->obj_list, elem) { + if (strcmp(obj->name, name) == 0) { + found = true; + break; + } + } + if (found == false) { + retval = -ENOENT; + goto exit; + } + return (void *)obj; + +exit: + pr_err("nameserver_get_handle failed! status = 0x%x", retval); + return (void *)NULL; +} +EXPORT_SYMBOL(nameserver_get_handle); + +/* ============================================================================= + * Internal functions + * ============================================================================= + */ +/* Function to register a remote driver for a processor */ +int nameserver_register_remote_driver(void *handle, u16 proc_id) +{ + s32 retval = 0; + u16 proc_count; + + if (WARN_ON(unlikely(atomic_cmpmask_and_lt( + &(nameserver_module->ref_count), + NAMESERVER_MAKE_MAGICSTAMP(0), + NAMESERVER_MAKE_MAGICSTAMP(1)) == true))) { + retval = -ENODEV; + goto exit; + } + if (WARN_ON(unlikely(handle == NULL))) { + retval = -EINVAL; + goto exit; + } + + proc_count = multiproc_get_num_processors(); + if (WARN_ON(unlikely(proc_id >= proc_count))) { + retval = -EINVAL; + goto exit; + } + + nameserver_module->remote_handle_list[proc_id] = \ + (struct nameserver_remote_object *)handle; + return 0; + +exit: + pr_err("nameserver_register_remote_driver failed! " + "status:%x\n", retval); + return retval; +} +EXPORT_SYMBOL(nameserver_register_remote_driver); + +/* Function to unregister a remote driver. */ +int nameserver_unregister_remote_driver(u16 proc_id) +{ + s32 retval = 0; + u16 proc_count; + + if (WARN_ON(unlikely(atomic_cmpmask_and_lt( + &(nameserver_module->ref_count), + NAMESERVER_MAKE_MAGICSTAMP(0), + NAMESERVER_MAKE_MAGICSTAMP(1)) == true))) { + retval = -ENODEV; + goto exit; + } + + proc_count = multiproc_get_num_processors(); + if (WARN_ON(proc_id >= proc_count)) { + retval = -EINVAL; + goto exit; + } + + nameserver_module->remote_handle_list[proc_id] = NULL; + return 0; + +exit: + pr_err("nameserver_unregister_remote_driver failed! " + "status:%x\n", retval); + return retval; +} +EXPORT_SYMBOL(nameserver_unregister_remote_driver); + +/* Determines if a remote driver is registered for the specified id. */ +bool nameserver_is_registered(u16 proc_id) +{ + bool registered = false; + s32 retval = 0; + + if (WARN_ON(unlikely(atomic_cmpmask_and_lt( + &(nameserver_module->ref_count), + NAMESERVER_MAKE_MAGICSTAMP(0), + NAMESERVER_MAKE_MAGICSTAMP(1)) == true))) { + retval = -ENODEV; + goto exit; + } + if (WARN_ON(unlikely(proc_id >= multiproc_get_num_processors()))) { + retval = -EINVAL; + goto exit; + } + + registered = (nameserver_module->remote_handle_list[proc_id] != NULL); + +exit: + if (retval < 0) { + pr_err("nameserver_is_registered failed! " + "status = 0x%x", retval); + } + return registered; +} +EXPORT_SYMBOL(nameserver_is_registered); + +/* Function to calculate hash for a string */ +static u32 _nameserver_string_hash(const char *string) +{ + u32 i; + u32 hash ; + u32 len = strlen(string); + + for (i = 0, hash = len; i < len; i++) + hash = (hash >> 8) ^ + nameserver_crc_table[(hash & 0xff)] ^ string[i]; + + return hash; +} + +#if 0 +/* This will return true if the entry is found in the table */ +static bool _nameserver_is_entry_found(const char *name, u32 hash, + struct list_head *list, + struct nameserver_table_entry **entry) +{ + struct nameserver_table_entry *node = NULL; + bool hash_match = false; + bool name_match = false; + + list_for_each_entry(node, list, elem) { + /* Hash not matches, take next node */ + if (node->hash == hash) + hash_match = true; + else + continue; + /* If the name matches, incase hash is duplicate */ + if (strcmp(node->name, name) == 0) + name_match = true; + + if (hash_match && name_match) { + if (entry != NULL) + *entry = node; + return true; + } + + hash_match = false; + name_match = false; + } + return false; +} +#endif + +/* This will return true if the hash is found in the table */ +static bool _nameserver_is_hash_found(const char *name, u32 hash, + struct list_head *list, + struct nameserver_table_entry **entry) +{ + struct nameserver_table_entry *node = NULL; + + /* No parameter checking as function is internal */ + + list_for_each_entry(node, list, elem) { + /* Hash not matches, take next node */ + if (node->hash == hash) { + *entry = node; + return true; + } + } + return false; +} + +/* This will return true if entry is found in the hash collide list */ +static bool _nameserver_check_for_entry(const char *name, + struct nameserver_table_entry **entry) +{ + struct nameserver_table_entry *temp = NULL; + bool found = false; + + /* No parameter checking as function is internal */ + + temp = *entry; + while (temp) { + if (strcmp(((struct nameserver_table_entry *)temp)->name, + name) == 0u) { + *entry = temp; + found = true; + break; + } + temp = temp->next; + } + + return found; +} |