block: IBM RamSan 70/80 driver fixes

This patch includes the following driver fixes for the
IBM RamSan 70/80 driver:

o Changed the creg_ctrl lock from a mutex to a spinlock.
o Added a count check for ioctl calls.
o Removed unnecessary casting of void pointers.
o Made every function static that needed to be.
o Added comments to explain things more thoroughly.

Signed-off-by: Philip J Kelleher <pjk1939@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/block/rsxx/config.c b/drivers/block/rsxx/config.c
index c8829cd..a295e7e 100644 (file)
--- a/drivers/block/rsxx/config.c
+++ b/drivers/block/rsxx/config.c
@@ -31,7 +31,7 @@
 
 static void initialize_config(void *config)
 {
-       struct rsxx_card_cfg *cfg = (struct rsxx_card_cfg *) config;
+       struct rsxx_card_cfg *cfg = config;
 
        cfg->hdr.version = RSXX_CFG_VERSION;
 
@@ -97,7 +97,7 @@ static void config_data_cpu_to_le(struct rsxx_card_cfg *cfg)
 
 
 /*----------------- Config Operations ------------------*/
-int rsxx_save_config(struct rsxx_cardinfo *card)
+static int rsxx_save_config(struct rsxx_cardinfo *card)
 {
        struct rsxx_card_cfg cfg;
        int st;

diff --git a/drivers/block/rsxx/core.c b/drivers/block/rsxx/core.c
index 83dadbe..e516248 100644 (file)
--- a/drivers/block/rsxx/core.c
+++ b/drivers/block/rsxx/core.c
@@ -102,9 +102,9 @@ void rsxx_disable_ier_and_isr(struct rsxx_cardinfo *card,
        iowrite32(card->ier_mask, card->regmap + IER);
 }
 
-irqreturn_t rsxx_isr(int irq, void *pdata)
+static irqreturn_t rsxx_isr(int irq, void *pdata)
 {
-       struct rsxx_cardinfo *card = (struct rsxx_cardinfo *) pdata;
+       struct rsxx_cardinfo *card = pdata;
        unsigned int isr;
        int handled = 0;
        int reread_isr;
@@ -161,6 +161,17 @@ irqreturn_t rsxx_isr(int irq, void *pdata)
 }
 
 /*----------------- Card Event Handler -------------------*/
+static char *rsxx_card_state_to_str(unsigned int state)
+{
+       static char *state_strings[] = {
+               "Unknown", "Shutdown", "Starting", "Formatting",
+               "Uninitialized", "Good", "Shutting Down",
+               "Fault", "Read Only Fault", "dStroying"
+       };
+
+       return state_strings[ffs(state)];
+}
+
 static void card_state_change(struct rsxx_cardinfo *card,
                              unsigned int new_state)
 {
@@ -251,18 +262,6 @@ static void card_event_handler(struct work_struct *work)
                rsxx_read_hw_log(card);
 }
 
-
-char *rsxx_card_state_to_str(unsigned int state)
-{
-       static char *state_strings[] = {
-               "Unknown", "Shutdown", "Starting", "Formatting",
-               "Uninitialized", "Good", "Shutting Down",
-               "Fault", "Read Only Fault", "dStroying"
-       };
-
-       return state_strings[ffs(state)];
-}
-
 /*----------------- Card Operations -------------------*/
 static int card_shutdown(struct rsxx_cardinfo *card)
 {
@@ -323,7 +322,6 @@ static int rsxx_pci_probe(struct pci_dev *dev,
                                        const struct pci_device_id *id)
 {
        struct rsxx_cardinfo *card;
-       unsigned long flags;
        int st;
 
        dev_info(&dev->dev, "PCI-Flash SSD discovered\n");
@@ -386,9 +384,9 @@ static int rsxx_pci_probe(struct pci_dev *dev,
        spin_lock_init(&card->irq_lock);
        card->halt = 0;
 
-       spin_lock_irqsave(&card->irq_lock, flags);
+       spin_lock_irq(&card->irq_lock);
        rsxx_disable_ier_and_isr(card, CR_INTR_ALL);
-       spin_unlock_irqrestore(&card->irq_lock, flags);
+       spin_unlock_irq(&card->irq_lock);
 
        if (!force_legacy) {
                st = pci_enable_msi(dev);
@@ -408,9 +406,9 @@ static int rsxx_pci_probe(struct pci_dev *dev,
        /************* Setup Processor Command Interface *************/
        rsxx_creg_setup(card);
 
-       spin_lock_irqsave(&card->irq_lock, flags);
+       spin_lock_irq(&card->irq_lock);
        rsxx_enable_ier_and_isr(card, CR_INTR_CREG);
-       spin_unlock_irqrestore(&card->irq_lock, flags);
+       spin_unlock_irq(&card->irq_lock);
 
        st = rsxx_compatibility_check(card);
        if (st) {
@@ -463,9 +461,9 @@ static int rsxx_pci_probe(struct pci_dev *dev,
         * we can enable the event interrupt(it kicks off actions in
         * those layers so we couldn't enable it right away.)
         */
-       spin_lock_irqsave(&card->irq_lock, flags);
+       spin_lock_irq(&card->irq_lock);
        rsxx_enable_ier_and_isr(card, CR_INTR_EVENT);
-       spin_unlock_irqrestore(&card->irq_lock, flags);
+       spin_unlock_irq(&card->irq_lock);
 
        if (card->state == CARD_STATE_SHUTDOWN) {
                st = rsxx_issue_card_cmd(card, CARD_CMD_STARTUP);
@@ -487,9 +485,9 @@ failed_create_dev:
        rsxx_dma_destroy(card);
 failed_dma_setup:
 failed_compatiblity_check:
-       spin_lock_irqsave(&card->irq_lock, flags);
+       spin_lock_irq(&card->irq_lock);
        rsxx_disable_ier_and_isr(card, CR_INTR_ALL);
-       spin_unlock_irqrestore(&card->irq_lock, flags);
+       spin_unlock_irq(&card->irq_lock);
        free_irq(dev->irq, card);
        if (!force_legacy)
                pci_disable_msi(dev);

diff --git a/drivers/block/rsxx/cregs.c b/drivers/block/rsxx/cregs.c
index a31fd72..80bbe63 100644 (file)
--- a/drivers/block/rsxx/cregs.c
+++ b/drivers/block/rsxx/cregs.c
@@ -107,10 +107,10 @@ static struct creg_cmd *pop_active_cmd(struct rsxx_cardinfo *card)
         * Spin lock is needed because this can be called in atomic/interrupt
         * context.
         */
-       spin_lock_bh(&card->creg_ctrl.pop_lock);
+       spin_lock_bh(&card->creg_ctrl.lock);
        cmd = card->creg_ctrl.active_cmd;
        card->creg_ctrl.active_cmd = NULL;
-       spin_unlock_bh(&card->creg_ctrl.pop_lock);
+       spin_unlock_bh(&card->creg_ctrl.lock);
 
        return cmd;
 }
@@ -126,7 +126,11 @@ static void creg_issue_cmd(struct rsxx_cardinfo *card, struct creg_cmd *cmd)
                                          cmd->buf, cmd->stream);
        }
 
-       /* Data copy must complete before initiating the command. */
+       /*
+        * Data copy must complete before initiating the command. This is
+        * needed for weakly ordered processors (i.e. PowerPC), so that all
+        * neccessary registers are written before we kick the hardware.
+        */
        wmb();
 
        /* Setting the valid bit will kick off the command. */
@@ -192,11 +196,11 @@ static int creg_queue_cmd(struct rsxx_cardinfo *card,
        cmd->cb_private = cb_private;
        cmd->status     = 0;
 
-       mutex_lock(&card->creg_ctrl.lock);
+       spin_lock(&card->creg_ctrl.lock);
        list_add_tail(&cmd->list, &card->creg_ctrl.queue);
        card->creg_ctrl.q_depth++;
        creg_kick_queue(card);
-       mutex_unlock(&card->creg_ctrl.lock);
+       spin_unlock(&card->creg_ctrl.lock);
 
        return 0;
 }
@@ -219,10 +223,11 @@ static void creg_cmd_timed_out(unsigned long data)
 
        kmem_cache_free(creg_cmd_pool, cmd);
 
-       spin_lock(&card->creg_ctrl.pop_lock);
+
+       spin_lock(&card->creg_ctrl.lock);
        card->creg_ctrl.active = 0;
        creg_kick_queue(card);
-       spin_unlock(&card->creg_ctrl.pop_lock);
+       spin_unlock(&card->creg_ctrl.lock);
 }
 
 
@@ -291,10 +296,10 @@ creg_done:
 
        kmem_cache_free(creg_cmd_pool, cmd);
 
-       mutex_lock(&card->creg_ctrl.lock);
+       spin_lock(&card->creg_ctrl.lock);
        card->creg_ctrl.active = 0;
        creg_kick_queue(card);
-       mutex_unlock(&card->creg_ctrl.lock);
+       spin_unlock(&card->creg_ctrl.lock);
 }
 
 static void creg_reset(struct rsxx_cardinfo *card)
@@ -303,6 +308,10 @@ static void creg_reset(struct rsxx_cardinfo *card)
        struct creg_cmd *tmp;
        unsigned long flags;
 
+       /*
+        * mutex_trylock is used here because if reset_lock is taken then a
+        * reset is already happening. So, we can just go ahead and return.
+        */
        if (!mutex_trylock(&card->creg_ctrl.reset_lock))
                return;
 
@@ -315,7 +324,7 @@ static void creg_reset(struct rsxx_cardinfo *card)
                "Resetting creg interface for recovery\n");
 
        /* Cancel outstanding commands */
-       mutex_lock(&card->creg_ctrl.lock);
+       spin_lock(&card->creg_ctrl.lock);
        list_for_each_entry_safe(cmd, tmp, &card->creg_ctrl.queue, list) {
                list_del(&cmd->list);
                card->creg_ctrl.q_depth--;
@@ -336,7 +345,7 @@ static void creg_reset(struct rsxx_cardinfo *card)
 
                card->creg_ctrl.active = 0;
        }
-       mutex_unlock(&card->creg_ctrl.lock);
+       spin_unlock(&card->creg_ctrl.lock);
 
        card->creg_ctrl.reset = 0;
        spin_lock_irqsave(&card->irq_lock, flags);
@@ -359,7 +368,7 @@ static void creg_cmd_done_cb(struct rsxx_cardinfo *card,
 {
        struct creg_completion *cmd_completion;
 
-       cmd_completion = (struct creg_completion *)cmd->cb_private;
+       cmd_completion = cmd->cb_private;
        BUG_ON(!cmd_completion);
 
        cmd_completion->st = st;
@@ -380,7 +389,6 @@ static int __issue_creg_rw(struct rsxx_cardinfo *card,
        unsigned long timeout;
        int st;
 
-       INIT_COMPLETION(cmd_done);
        completion.cmd_done = &cmd_done;
        completion.st = 0;
        completion.creg_status = 0;
@@ -390,8 +398,13 @@ static int __issue_creg_rw(struct rsxx_cardinfo *card,
        if (st)
                return st;
 
+       /*
+        * This timeout is neccessary for unresponsive hardware. The additional
+        * 20 seconds to used to guarantee that each cregs requests has time to
+        * complete.
+        */
        timeout = msecs_to_jiffies((CREG_TIMEOUT_MSEC *
-                                   card->creg_ctrl.q_depth) + 20000);
+                               card->creg_ctrl.q_depth) + 20000);
 
        /*
         * The creg interface is guaranteed to complete. It has a timeout
@@ -443,7 +456,7 @@ static int issue_creg_rw(struct rsxx_cardinfo *card,
                if (st)
                        return st;
 
-               data   = (void *)((char *)data + xfer);
+               data   = (char *)data + xfer;
                addr  += xfer;
                size8 -= xfer;
        } while (size8);
@@ -558,9 +571,9 @@ static void hw_log_msg(struct rsxx_cardinfo *card, const char *str, int len)
 }
 
 /*
- * The substrncpy() function copies to string(up to count bytes) point to by src
- * (including the terminating '\0' character) to dest. Returns the number of
- * bytes copied to dest.
+ * The substrncpy function copies the src string (which includes the
+ * terminating '\0' character), up to the count into the dest pointer.
+ * Returns the number of bytes copied to dest.
  */
 static int substrncpy(char *dest, const char *src, int count)
 {
@@ -657,6 +670,9 @@ int rsxx_reg_access(struct rsxx_cardinfo *card,
        if (st)
                return -EFAULT;
 
+       if (cmd.cnt > RSXX_MAX_REG_CNT)
+               return -EFAULT;
+
        st = issue_reg_cmd(card, &cmd, read);
        if (st)
                return st;
@@ -682,8 +698,7 @@ int rsxx_creg_setup(struct rsxx_cardinfo *card)
        INIT_WORK(&card->creg_ctrl.done_work, creg_cmd_done);
        mutex_init(&card->creg_ctrl.reset_lock);
        INIT_LIST_HEAD(&card->creg_ctrl.queue);
-       mutex_init(&card->creg_ctrl.lock);
-       spin_lock_init(&card->creg_ctrl.pop_lock);
+       spin_lock_init(&card->creg_ctrl.lock);
        setup_timer(&card->creg_ctrl.cmd_timer, creg_cmd_timed_out,
                    (unsigned long) card);
 
@@ -697,7 +712,7 @@ void rsxx_creg_destroy(struct rsxx_cardinfo *card)
        int cnt = 0;
 
        /* Cancel outstanding commands */
-       mutex_lock(&card->creg_ctrl.lock);
+       spin_lock(&card->creg_ctrl.lock);
        list_for_each_entry_safe(cmd, tmp, &card->creg_ctrl.queue, list) {
                list_del(&cmd->list);
                if (cmd->cb)
@@ -722,7 +737,7 @@ void rsxx_creg_destroy(struct rsxx_cardinfo *card)
                        "Canceled active creg command\n");
                kmem_cache_free(creg_cmd_pool, cmd);
        }
-       mutex_unlock(&card->creg_ctrl.lock);
+       spin_unlock(&card->creg_ctrl.lock);
 
        cancel_work_sync(&card->creg_ctrl.done_work);
 }

diff --git a/drivers/block/rsxx/dev.c b/drivers/block/rsxx/dev.c
index 96df053..4346d17 100644 (file)
--- a/drivers/block/rsxx/dev.c
+++ b/drivers/block/rsxx/dev.c
@@ -149,7 +149,7 @@ static void bio_dma_done_cb(struct rsxx_cardinfo *card,
                            void *cb_data,
                            unsigned int error)
 {
-       struct rsxx_bio_meta *meta = (struct rsxx_bio_meta *)cb_data;
+       struct rsxx_bio_meta *meta = cb_data;
 
        if (error)
                atomic_set(&meta->error, 1);

diff --git a/drivers/block/rsxx/dma.c b/drivers/block/rsxx/dma.c
index 872f503..63176e6 100644 (file)
--- a/drivers/block/rsxx/dma.c
+++ b/drivers/block/rsxx/dma.c
@@ -102,7 +102,7 @@ struct dma_tracker_list {
 
 
 /*----------------- Misc Utility Functions -------------------*/
-unsigned int rsxx_addr8_to_laddr(u64 addr8, struct rsxx_cardinfo *card)
+static unsigned int rsxx_addr8_to_laddr(u64 addr8, struct rsxx_cardinfo *card)
 {
        unsigned long long tgt_addr8;
 
@@ -113,7 +113,7 @@ unsigned int rsxx_addr8_to_laddr(u64 addr8, struct rsxx_cardinfo *card)
        return tgt_addr8;
 }
 
-unsigned int rsxx_get_dma_tgt(struct rsxx_cardinfo *card, u64 addr8)
+static unsigned int rsxx_get_dma_tgt(struct rsxx_cardinfo *card, u64 addr8)
 {
        unsigned int tgt;
 
@@ -757,7 +757,7 @@ static int rsxx_dma_ctrl_init(struct pci_dev *dev,
        INIT_LIST_HEAD(&ctrl->queue);
 
        setup_timer(&ctrl->activity_timer, dma_engine_stalled,
-                   (unsigned long)ctrl);
+                                       (unsigned long)ctrl);
 
        ctrl->issue_wq = alloc_ordered_workqueue(DRIVER_NAME"_issue", 0);
        if (!ctrl->issue_wq)
@@ -803,7 +803,7 @@ static int rsxx_dma_ctrl_init(struct pci_dev *dev,
        return 0;
 }
 
-int rsxx_dma_stripe_setup(struct rsxx_cardinfo *card,
+static int rsxx_dma_stripe_setup(struct rsxx_cardinfo *card,
                              unsigned int stripe_size8)
 {
        if (!is_power_of_2(stripe_size8)) {
@@ -834,7 +834,7 @@ int rsxx_dma_stripe_setup(struct rsxx_cardinfo *card,
        return 0;
 }
 
-int rsxx_dma_configure(struct rsxx_cardinfo *card)
+static int rsxx_dma_configure(struct rsxx_cardinfo *card)
 {
        u32 intr_coal;
 

diff --git a/drivers/block/rsxx/rsxx.h b/drivers/block/rsxx/rsxx.h
index 9581e13..2e50b65 100644 (file)
--- a/drivers/block/rsxx/rsxx.h
+++ b/drivers/block/rsxx/rsxx.h
@@ -35,6 +35,8 @@ struct rsxx_reg_access {
        __u32 data[8];
 };
 
+#define RSXX_MAX_REG_CNT       (8 * (sizeof(__u32)))
+
 #define RSXX_IOC_MAGIC 'r'
 
 #define RSXX_GETREG _IOWR(RSXX_IOC_MAGIC, 0x20, struct rsxx_reg_access)

diff --git a/drivers/block/rsxx/rsxx_priv.h b/drivers/block/rsxx/rsxx_priv.h
index 3887e49..a1ac907 100644 (file)
--- a/drivers/block/rsxx/rsxx_priv.h
+++ b/drivers/block/rsxx/rsxx_priv.h
@@ -127,7 +127,7 @@ struct rsxx_cardinfo {
 
        /* Embedded CPU Communication */
        struct {
-               struct mutex            lock;
+               spinlock_t              lock;
                bool                    active;
                struct creg_cmd         *active_cmd;
                struct work_struct      done_work;
@@ -141,7 +141,6 @@ struct rsxx_cardinfo {
                } creg_stats;
                struct timer_list       cmd_timer;
                struct mutex            reset_lock;
-               spinlock_t              pop_lock;
                int                     reset;
        } creg_ctrl;
 
@@ -336,7 +335,6 @@ static inline unsigned int CREG_DATA(int N)
 
 /***** config.c *****/
 int rsxx_load_config(struct rsxx_cardinfo *card);
-int rsxx_save_config(struct rsxx_cardinfo *card);
 
 /***** core.c *****/
 void rsxx_enable_ier(struct rsxx_cardinfo *card, unsigned int intr);
@@ -345,8 +343,6 @@ void rsxx_enable_ier_and_isr(struct rsxx_cardinfo *card,
                                 unsigned int intr);
 void rsxx_disable_ier_and_isr(struct rsxx_cardinfo *card,
                                  unsigned int intr);
-char *rsxx_card_state_to_str(unsigned int state);
-irqreturn_t rsxx_isr(int irq, void *pdata);
 
 /***** dev.c *****/
 int rsxx_attach_dev(struct rsxx_cardinfo *card);
@@ -364,16 +360,11 @@ int rsxx_dma_setup(struct rsxx_cardinfo *card);
 void rsxx_dma_destroy(struct rsxx_cardinfo *card);
 int rsxx_dma_init(void);
 void rsxx_dma_cleanup(void);
-int rsxx_dma_configure(struct rsxx_cardinfo *card);
 int rsxx_dma_queue_bio(struct rsxx_cardinfo *card,
                           struct bio *bio,
                           atomic_t *n_dmas,
                           rsxx_dma_cb cb,
                           void *cb_data);
-int rsxx_dma_stripe_setup(struct rsxx_cardinfo *card,
-                             unsigned int stripe_size8);
-unsigned int rsxx_get_dma_tgt(struct rsxx_cardinfo *card, u64 addr8);
-unsigned int rsxx_addr8_to_laddr(u64 addr8, struct rsxx_cardinfo *card);
 
 /***** cregs.c *****/
 int rsxx_creg_write(struct rsxx_cardinfo *card, u32 addr,