ide: /proc/ide/hd*/settings rework

* Add struct ide_devset, S_* flags, *DEVSET() & ide*_devset_*() macros.

* Add 'const struct ide_devset **settings' to ide_driver_t.

* Use 'const struct ide_devset **settings' in ide_drive_t instead of
  'struct ide_settings_s *settings'.  Then convert core code and device
  drivers to use struct ide_devset and co.:

  - device settings are no longer allocated dynamically for each device
    but instead there is an unique struct ide_devset instance per setting

  - device driver keeps the pointer to the table of pointers to its
    settings in ide_driver_t.settings

  - generic settings are kept in ide_generic_setting[]

  - ide_proc_[un]register_driver(), ide_find_setting_by_name(),
    ide_{read,write}_setting() and proc_ide_{read,write}_settings()
    are updated accordingly

  - ide*_add_settings() are removed

* Remove no longer used __ide_add_setting(), ide_add_setting(),
  __ide_remove_setting() and auto_remove_settings().

* Remove no longer used TYPE_*, SETTING_*, ide_procset_t
  and ide_settings_t.

* ->keep_settings, ->using_dma, ->unmask, ->noflush, ->dsc_overlap,
  ->nice1, ->addressing, ->wcache and ->nowerr ide_drive_t fields
  can now be bitfield flags.

While at it:

* Rename ide_find_setting_by_name() to ide_find_setting().

* Rename write_wcache() to set_wcache().

There should be no functional changes caused by this patch.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

1 files changed, 87 insertions, 192 deletions

diff --git a/drivers/ide/ide-proc.c b/drivers/ide/ide-proc.c
index 7a64aedfa648..5634b3971d21 100644
--- a/drivers/ide/ide-proc.c
+++ b/drivers/ide/ide-proc.c
@@ -114,140 +114,24 @@ static int proc_ide_read_identify
 }
 
 /**
- *      __ide_add_setting       -       add an ide setting option
- *      @drive: drive to use
+ *      ide_find_setting        -       find a specific setting
+ *      @st: setting table pointer
  *      @name: setting name
- *      @rw: true if the function is read write
- *      @data_type: type of data
- *      @min: range minimum
- *      @max: range maximum
- *      @mul_factor: multiplication scale
- *      @div_factor: divison scale
- *      @data: private data field
- *      @set: setting
- *      @auto_remove: setting auto removal flag
  *
- *      Removes the setting named from the device if it is present.
- *      The function takes the settings_lock to protect against
- *      parallel changes. This function must not be called from IRQ
- *      context. Returns 0 on success or -1 on failure.
- *
- *      BUGS: This code is seriously over-engineered. There is also
- *      magic about how the driver specific features are setup. If
- *      a driver is attached we assume the driver settings are auto
- *      remove.
- */
-
-static int __ide_add_setting(ide_drive_t *drive, const char *name, int rw, int data_type, int min, int max, int mul_factor, int div_factor, void *data, ide_procset_t *set, int auto_remove)
-{
-        ide_settings_t **p = (ide_settings_t **) &drive->settings, *setting = NULL;
-
-        mutex_lock(&ide_setting_mtx);
-        while ((*p) && strcmp((*p)->name, name) < 0)
-                p = &((*p)->next);
-        if ((setting = kzalloc(sizeof(*setting), GFP_KERNEL)) == NULL)
-                goto abort;
-        if ((setting->name = kmalloc(strlen(name) + 1, GFP_KERNEL)) == NULL)
-                goto abort;
-        strcpy(setting->name, name);
-        setting->rw = rw;
-        setting->data_type = data_type;
-        setting->min = min;
-        setting->max = max;
-        setting->mul_factor = mul_factor;
-        setting->div_factor = div_factor;
-        setting->data = data;
-        setting->set = set;
-
-        setting->next = *p;
-        if (auto_remove)
-                setting->auto_remove = 1;
-        *p = setting;
-        mutex_unlock(&ide_setting_mtx);
-        return 0;
-abort:
-        mutex_unlock(&ide_setting_mtx);
-        kfree(setting);
-        return -1;
-}
-
-int ide_add_setting(ide_drive_t *drive, const char *name, int rw, int data_type, int min, int max, int mul_factor, int div_factor, void *data, ide_procset_t *set)
-{
-        return __ide_add_setting(drive, name, rw, data_type, min, max, mul_factor, div_factor, data, set, 1);
-}
-
-EXPORT_SYMBOL(ide_add_setting);
-
-/**
- *      __ide_remove_setting    -       remove an ide setting option
- *      @drive: drive to use
- *      @name: setting name
- *
- *      Removes the setting named from the device if it is present.
- *      The caller must hold the setting semaphore.
- */
-
-static void __ide_remove_setting(ide_drive_t *drive, char *name)
-{
-        ide_settings_t **p, *setting;
-
-        p = (ide_settings_t **) &drive->settings;
-
-        while ((*p) && strcmp((*p)->name, name))
-                p = &((*p)->next);
-        setting = (*p);
-        if (setting == NULL)
-                return;
-
-        (*p) = setting->next;
-
-        kfree(setting->name);
-        kfree(setting);
-}
-
-/**
- *      auto_remove_settings    -       remove driver specific settings
- *      @drive: drive
- *
- *      Automatically remove all the driver specific settings for this
- *      drive. This function may not be called from IRQ context. The
- *      caller must hold ide_setting_mtx.
- */
-
-static void auto_remove_settings(ide_drive_t *drive)
-{
-        ide_settings_t *setting;
-repeat:
-        setting = drive->settings;
-        while (setting) {
-                if (setting->auto_remove) {
-                        __ide_remove_setting(drive, setting->name);
-                        goto repeat;
-                }
-                setting = setting->next;
-        }
-}
-
-/**
- *      ide_find_setting_by_name        -       find a drive specific setting
- *      @drive: drive to scan
- *      @name: setting name
- *
- *      Scan's the device setting table for a matching entry and returns
+ *      Scan's the setting table for a matching entry and returns
  *      this or NULL if no entry is found. The caller must hold the
  *      setting semaphore
  */
 
-static ide_settings_t *ide_find_setting_by_name(ide_drive_t *drive, char *name)
+static const struct ide_devset *ide_find_setting(const struct ide_devset **st,
+                                                 char *name)
 {
-        ide_settings_t *setting = drive->settings;
-
-        while (setting) {
-                if (strcmp(setting->name, name) == 0)
+        while (*st) {
+                if (strcmp((*st)->name, name) == 0)
                         break;
-                setting = setting->next;
+                st++;
         }
-        return setting;
+        return *st;
 }
 
 /**
@@ -263,26 +147,19 @@ static ide_settings_t *ide_find_setting_by_name(ide_drive_t *drive, char *name)
  *      be told apart
  */
 
-static int ide_read_setting(ide_drive_t *drive, ide_settings_t *setting)
+static int ide_read_setting(ide_drive_t *drive,
+                            const struct ide_devset *setting)
 {
-        int             val = -EINVAL;
-        unsigned long   flags;
+        int val = -EINVAL;
+
+        if ((setting->flags & S_READ)) {
+                unsigned long flags;
 
-        if ((setting->rw & SETTING_READ)) {
                 spin_lock_irqsave(&ide_lock, flags);
-                switch (setting->data_type) {
-                case TYPE_BYTE:
-                        val = *((u8 *) setting->data);
-                        break;
-                case TYPE_SHORT:
-                        val = *((u16 *) setting->data);
-                        break;
-                case TYPE_INT:
-                        val = *((u32 *) setting->data);
-                        break;
-                }
+                val = setting->get(drive);
                 spin_unlock_irqrestore(&ide_lock, flags);
         }
+
         return val;
 }
 
@@ -304,33 +181,26 @@ static int ide_read_setting(ide_drive_t *drive, ide_settings_t *setting)
  *      The current scheme of polling is kludgy, though safe enough.
  */
 
-static int ide_write_setting(ide_drive_t *drive, ide_settings_t *setting, int val)
+static int ide_write_setting(ide_drive_t *drive,
+                             const struct ide_devset *setting, int val)
 {
         if (!capable(CAP_SYS_ADMIN))
                 return -EACCES;
-        if (setting->set)
+        if (setting->set && (setting->flags & S_NOLOCK))
                 return setting->set(drive, val);
-        if (!(setting->rw & SETTING_WRITE))
+        if (!(setting->flags & S_WRITE))
                 return -EPERM;
         if (val < setting->min || val > setting->max)
                 return -EINVAL;
         if (ide_spin_wait_hwgroup(drive))
                 return -EBUSY;
-        switch (setting->data_type) {
-        case TYPE_BYTE:
-                *((u8 *) setting->data) = val;
-                break;
-        case TYPE_SHORT:
-                *((u16 *) setting->data) = val;
-                break;
-        case TYPE_INT:
-                *((u32 *) setting->data) = val;
-                break;
-        }
+        setting->set(drive, val);
         spin_unlock_irq(&ide_lock);
         return 0;
 }
 
+static ide_devset_get(xfer_rate, current_speed);
+
 static int set_xfer_rate (ide_drive_t *drive, int arg)
 {
         ide_task_t task;
@@ -355,29 +225,30 @@ static int set_xfer_rate (ide_drive_t *drive, int arg)
         return err;
 }
 
-/**
- *      ide_add_generic_settings        -       generic ide settings
- *      @drive: drive being configured
- *
- *      Add the generic parts of the system settings to the /proc files.
- *      The caller must not be holding the ide_setting_mtx.
- */
-
-void ide_add_generic_settings (ide_drive_t *drive)
-{
-/*
- *                        drive         setting name            read/write access                               data type       min     max                             mul_factor      div_factor      data pointer                    set function
- */
-        __ide_add_setting(drive,        "io_32bit",             SETTING_RW,                                     TYPE_BYTE,      0,      1 + (SUPPORT_VLB_SYNC << 1),    1,              1,              &drive->io_32bit,               set_io_32bit,   0);
-        __ide_add_setting(drive,        "keepsettings",         SETTING_RW,                                     TYPE_BYTE,      0,      1,                              1,              1,              &drive->keep_settings,          set_ksettings,  0);
-        __ide_add_setting(drive,        "nice1",                SETTING_RW,                                     TYPE_BYTE,      0,      1,                              1,              1,              &drive->nice1,                  NULL,           0);
-        __ide_add_setting(drive,        "pio_mode",             SETTING_WRITE,                                  TYPE_BYTE,      0,      255,                            1,              1,              NULL,                           set_pio_mode,   0);
-        __ide_add_setting(drive,        "unmaskirq",            SETTING_RW,                                     TYPE_BYTE,      0,      1,                              1,              1,              &drive->unmask,                 set_unmaskirq,  0);
-        __ide_add_setting(drive,        "using_dma",            SETTING_RW,                                     TYPE_BYTE,      0,      1,                              1,              1,              &drive->using_dma,              set_using_dma,  0);
-        __ide_add_setting(drive,        "init_speed",           SETTING_RW,                                     TYPE_BYTE,      0,      70,                             1,              1,              &drive->init_speed,             NULL,           0);
-        __ide_add_setting(drive,        "current_speed",        SETTING_RW,                                     TYPE_BYTE,      0,      70,                             1,              1,              &drive->current_speed,          set_xfer_rate,  0);
-        __ide_add_setting(drive,        "number",               SETTING_RW,                                     TYPE_BYTE,      0,      3,                              1,              1,              &drive->dn,                     NULL,           0);
-}
+ide_devset_rw_nolock(current_speed, 0, 70, xfer_rate);
+ide_devset_rw_nolock(io_32bit, 0, 1 + (SUPPORT_VLB_SYNC << 1), io_32bit);
+ide_devset_rw_nolock(keepsettings, 0, 1, ksettings);
+ide_devset_rw_nolock(unmaskirq, 0, 1, unmaskirq);
+ide_devset_rw_nolock(using_dma, 0, 1, using_dma);
+
+ide_devset_w_nolock(pio_mode, 0, 255, pio_mode);
+
+ide_devset_rw(init_speed, 0, 70, init_speed);
+ide_devset_rw(nice1, 0, 1, nice1);
+ide_devset_rw(number, 0, 3, dn);
+
+static const struct ide_devset *ide_generic_settings[] = {
+        &ide_devset_current_speed,
+        &ide_devset_init_speed,
+        &ide_devset_io_32bit,
+        &ide_devset_keepsettings,
+        &ide_devset_nice1,
+        &ide_devset_number,
+        &ide_devset_pio_mode,
+        &ide_devset_unmaskirq,
+        &ide_devset_using_dma,
+        NULL
+};
 
 static void proc_ide_settings_warn(void)
 {
@@ -394,19 +265,31 @@ static void proc_ide_settings_warn(void)
 static int proc_ide_read_settings
         (char *page, char **start, off_t off, int count, int *eof, void *data)
 {
+        const struct ide_devset *setting, **g, **d;
         ide_drive_t     *drive = (ide_drive_t *) data;
-        ide_settings_t  *setting = (ide_settings_t *) drive->settings;
         char            *out = page;
         int             len, rc, mul_factor, div_factor;
 
         proc_ide_settings_warn();
 
         mutex_lock(&ide_setting_mtx);
+        g = ide_generic_settings;
+        d = drive->settings;
         out += sprintf(out, "name\t\t\tvalue\t\tmin\t\tmax\t\tmode\n");
         out += sprintf(out, "----\t\t\t-----\t\t---\t\t---\t\t----\n");
-        while (setting) {
-                mul_factor = setting->mul_factor;
-                div_factor = setting->div_factor;
+        while (*g || (d && *d)) {
+                /* read settings in the alphabetical order */
+                if (*g && d && *d) {
+                        if (strcmp((*d)->name, (*g)->name) < 0)
+                                setting = *d++;
+                        else
+                                setting = *g++;
+                } else if (d && *d) {
+                        setting = *d++;
+                } else
+                        setting = *g++;
+                mul_factor = setting->mulf ? setting->mulf(drive) : 1;
+                div_factor = setting->divf ? setting->divf(drive) : 1;
                 out += sprintf(out, "%-24s", setting->name);
                 rc = ide_read_setting(drive, setting);
                 if (rc >= 0)
@@ -414,12 +297,11 @@ static int proc_ide_read_settings
                 else
                         out += sprintf(out, "%-16s", "write-only");
                 out += sprintf(out, "%-16d%-16d", (setting->min * mul_factor + div_factor - 1) / div_factor, setting->max * mul_factor / div_factor);
-                if (setting->rw & SETTING_READ)
+                if (setting->flags & S_READ)
                         out += sprintf(out, "r");
-                if (setting->rw & SETTING_WRITE)
+                if (setting->flags & S_WRITE)
                         out += sprintf(out, "w");
                 out += sprintf(out, "\n");
-                setting = setting->next;
         }
         len = out - page;
         mutex_unlock(&ide_setting_mtx);
@@ -433,9 +315,10 @@ static int proc_ide_write_settings(struct file *file, const char __user *buffer,
 {
         ide_drive_t     *drive = (ide_drive_t *) data;
         char            name[MAX_LEN + 1];
-        int             for_real = 0;
+        int             for_real = 0, mul_factor, div_factor;
         unsigned long   n;
-        ide_settings_t  *setting;
+
+        const struct ide_devset *setting;
         char *buf, *s;
 
         if (!capable(CAP_SYS_ADMIN))
@@ -503,13 +386,21 @@ static int proc_ide_write_settings(struct file *file, const char __user *buffer,
                         }
 
                         mutex_lock(&ide_setting_mtx);
-                        setting = ide_find_setting_by_name(drive, name);
+                        /* generic settings first, then driver specific ones */
+                        setting = ide_find_setting(ide_generic_settings, name);
                         if (!setting) {
-                                mutex_unlock(&ide_setting_mtx);
-                                goto parse_error;
+                                if (drive->settings)
+                                        setting = ide_find_setting(drive->settings, name);
+                                if (!setting) {
+                                        mutex_unlock(&ide_setting_mtx);
+                                        goto parse_error;
+                                }
+                        }
+                        if (for_real) {
+                                mul_factor = setting->mulf ? setting->mulf(drive) : 1;
+                                div_factor = setting->divf ? setting->divf(drive) : 1;
+                                ide_write_setting(drive, setting, val * div_factor / mul_factor);
                         }
-                        if (for_real)
-                                ide_write_setting(drive, setting, val * setting->div_factor / setting->mul_factor);
                         mutex_unlock(&ide_setting_mtx);
                 }
         } while (!for_real++);
@@ -680,6 +571,10 @@ static void ide_remove_proc_entries(struct proc_dir_entry *dir, ide_proc_entry_t
 
 void ide_proc_register_driver(ide_drive_t *drive, ide_driver_t *driver)
 {
+        mutex_lock(&ide_setting_mtx);
+        drive->settings = driver->settings;
+        mutex_unlock(&ide_setting_mtx);
+
         ide_add_proc_entries(drive->proc, driver->proc, drive);
 }
 
@@ -716,7 +611,7 @@ void ide_proc_unregister_driver(ide_drive_t *drive, ide_driver_t *driver)
          * OTOH both ide_{read,write}_setting are only ever used under
          * ide_setting_mtx.
          */
-        auto_remove_settings(drive);
+        drive->settings = NULL;
         spin_unlock_irqrestore(&ide_lock, flags);
         mutex_unlock(&ide_setting_mtx);
 }