diff options
Diffstat (limited to 'drivers/mxc/security/sahara2/sah_queue.c')
| -rw-r--r-- | drivers/mxc/security/sahara2/sah_queue.c | 249 |
1 files changed, 249 insertions, 0 deletions
diff --git a/drivers/mxc/security/sahara2/sah_queue.c b/drivers/mxc/security/sahara2/sah_queue.c new file mode 100644 index 000000000000..317a60b92b6b --- /dev/null +++ b/drivers/mxc/security/sahara2/sah_queue.c @@ -0,0 +1,249 @@ +/* + * Copyright (C) 2004-2010 Freescale Semiconductor, Inc. All Rights Reserved. + */ + +/* + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ + +/*! +* @file sah_queue.c +* +* @brief This file provides a FIFO Queue implementation. +* +*/ +/****************************************************************************** +* +* CAUTION: +******************************************************************* +*/ + +/* SAHARA Includes */ +#include <sah_queue_manager.h> +#ifdef DIAG_DRV_QUEUE +#include <diagnostic.h> +#endif + +/****************************************************************************** +* Queue Functions +******************************************************************************/ + +/*! +******************************************************************************* +* This function constructs a new sah_Queue. +* +* @brief sah_Queue Constructor +* +* @return A pointer to a newly allocated sah_Queue. +* @return NULL if allocation of memory failed. +*/ +/****************************************************************************** +* +* CAUTION: This function may sleep in low-memory situations, as it uses +* kmalloc ( ..., GFP_KERNEL). +******************************************************************************/ +sah_Queue *sah_Queue_Construct(void) +{ + sah_Queue *q = (sah_Queue *) os_alloc_memory(sizeof(sah_Queue), + GFP_KERNEL); + + if (q != NULL) { + /* Initialise the queue to an empty state. */ + q->head = NULL; + q->tail = NULL; + q->count = 0; + } +#ifdef DIAG_DRV_QUEUE + else { + LOG_KDIAG("kmalloc() failed."); + } +#endif + + return q; +} + +/*! +******************************************************************************* +* This function destroys a sah_Queue. +* +* @brief sah_Queue Destructor +* +* @param q A pointer to a sah_Queue. +* +* @return void +*/ +/****************************************************************************** +* +* CAUTION: This function does not free any queue entries. +* +******************************************************************************/ +void sah_Queue_Destroy(sah_Queue * q) +{ +#ifdef DIAG_DRV_QUEUE + if (q == NULL) { + LOG_KDIAG("Trying to kfree() a NULL pointer."); + } else { + if (q->count != 0) { + LOG_KDIAG + ("Trying to destroy a queue that is not empty."); + } + } +#endif + + if (q != NULL) { + os_free_memory(q); + q = NULL; + } +} + +/*! +******************************************************************************* +* This function appends a sah_Head_Desc to the tail of a sah_Queue. +* +* @brief Appends a sah_Head_Desc to a sah_Queue. +* +* @param q A pointer to a sah_Queue to append to. +* @param entry A pointer to a sah_Head_Desc to append. +* +* @pre The #desc_queue_lock must be held before calling this function. +* +* @return void +*/ +/****************************************************************************** +* +* CAUTION: NONE +******************************************************************************/ +void sah_Queue_Append_Entry(sah_Queue * q, sah_Head_Desc * entry) +{ + sah_Head_Desc *tail_entry = NULL; + + if ((q == NULL) || (entry == NULL)) { +#ifdef DIAG_DRV_QUEUE + LOG_KDIAG("Null pointer input."); +#endif + return; + } + + if (q->count == 0) { + /* The queue is empty */ + q->head = entry; + q->tail = entry; + entry->next = NULL; + entry->prev = NULL; + } else { + /* The queue is not empty */ + tail_entry = q->tail; + tail_entry->next = entry; + entry->next = NULL; + entry->prev = tail_entry; + q->tail = entry; + } + q->count++; +} + +/*! +******************************************************************************* +* This function a removes a sah_Head_Desc from the head of a sah_Queue. +* +* @brief Removes a sah_Head_Desc from a the head of a sah_Queue. +* +* @param q A pointer to a sah_Queue to remove from. +* +* @pre The #desc_queue_lock must be held before calling this function. +* +* @return void +*/ +/****************************************************************************** +* +* CAUTION: This does not kfree() the entry. +******************************************************************************/ +void sah_Queue_Remove_Entry(sah_Queue * q) +{ + sah_Queue_Remove_Any_Entry(q, q->head); +} + +/*! +******************************************************************************* +* This function a removes a sah_Head_Desc from anywhere in a sah_Queue. +* +* @brief Removes a sah_Head_Desc from anywhere in a sah_Queue. +* +* @param qq A pointer to a sah_Queue to remove from. +* @param entry A pointer to a sah_Head_Desc to remove. +* +* @pre The #desc_queue_lock must be held before calling this function. +* +* @return void +*/ +/****************************************************************************** +* +* CAUTION: This does not kfree() the entry. Does not check to see if the entry +* actually belongs to the queue. +******************************************************************************/ +void sah_Queue_Remove_Any_Entry(sah_Queue * q, sah_Head_Desc * entry) +{ + sah_Head_Desc *prev_entry = NULL; + sah_Head_Desc *next_entry = NULL; + + if ((q == NULL) || (entry == NULL)) { +#if defined DIAG_DRV_QUEUE && defined DIAG_DURING_INTERRUPT + LOG_KDIAG("Null pointer input."); +#endif + return; + } + + if (q->count == 1) { + /* If q is the only entry in the queue. */ + q->tail = NULL; + q->head = NULL; + q->count = 0; + } else if (q->count > 1) { + /* There are 2 or more entries in the queue. */ + +#if defined DIAG_DRV_QUEUE && defined DIAG_DURING_INTERRUPT + if ((entry->next == NULL) && (entry->prev == NULL)) { + LOG_KDIAG + ("Queue is not empty yet both next and prev pointers" + " are NULL"); + } +#endif + + if (entry->next == NULL) { + /* If this is the end of the queue */ + prev_entry = entry->prev; + prev_entry->next = NULL; + q->tail = prev_entry; + } else if (entry->prev == NULL) { + /* If this is the head of the queue */ + next_entry = entry->next; + next_entry->prev = NULL; + q->head = next_entry; + } else { + /* If this is somewhere in the middle of the queue */ + prev_entry = entry->prev; + next_entry = entry->next; + prev_entry->next = next_entry; + next_entry->prev = prev_entry; + } + q->count--; + } + /* + * Otherwise we are removing an entry from an empty queue. + * Don't do anything in the product code + */ +#if defined DIAG_DRV_QUEUE && defined DIAG_DURING_INTERRUPT + else { + LOG_KDIAG("Trying to remove an entry from an empty queue."); + } +#endif + + entry->next = NULL; + entry->prev = NULL; +} + +/* End of sah_queue.c */ |