X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=mm%2Fbacking-dev.c;h=08361b6aad5044f5f37a18e6eb162b034848578b;hb=a42dde04152750426cc620fd277e80fffae2f65a;hp=e5de3781d3feed5b6f156b064b4af8bb79871fed;hpb=e0cc09e295f346b7921e921f385fe5213472316a;p=linux-2.6 diff --git a/mm/backing-dev.c b/mm/backing-dev.c index e5de3781d3..08361b6aad 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -4,6 +4,202 @@ #include #include #include +#include +#include + + +static struct class *bdi_class; + +static ssize_t read_ahead_kb_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct backing_dev_info *bdi = dev_get_drvdata(dev); + char *end; + unsigned long read_ahead_kb; + ssize_t ret = -EINVAL; + + read_ahead_kb = simple_strtoul(buf, &end, 10); + if (*buf && (end[0] == '\0' || (end[0] == '\n' && end[1] == '\0'))) { + bdi->ra_pages = read_ahead_kb >> (PAGE_SHIFT - 10); + ret = count; + } + return ret; +} + +#define K(pages) ((pages) << (PAGE_SHIFT - 10)) + +#define BDI_SHOW(name, expr) \ +static ssize_t name##_show(struct device *dev, \ + struct device_attribute *attr, char *page) \ +{ \ + struct backing_dev_info *bdi = dev_get_drvdata(dev); \ + \ + return snprintf(page, PAGE_SIZE-1, "%lld\n", (long long)expr); \ +} + +BDI_SHOW(read_ahead_kb, K(bdi->ra_pages)) + +BDI_SHOW(reclaimable_kb, K(bdi_stat(bdi, BDI_RECLAIMABLE))) +BDI_SHOW(writeback_kb, K(bdi_stat(bdi, BDI_WRITEBACK))) + +static inline unsigned long get_dirty(struct backing_dev_info *bdi, int i) +{ + unsigned long thresh[3]; + + get_dirty_limits(&thresh[0], &thresh[1], &thresh[2], bdi); + + return thresh[i]; +} + +BDI_SHOW(dirty_kb, K(get_dirty(bdi, 1))) +BDI_SHOW(bdi_dirty_kb, K(get_dirty(bdi, 2))) + +static ssize_t min_ratio_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t count) +{ + struct backing_dev_info *bdi = dev_get_drvdata(dev); + char *end; + unsigned int ratio; + ssize_t ret = -EINVAL; + + ratio = simple_strtoul(buf, &end, 10); + if (*buf && (end[0] == '\0' || (end[0] == '\n' && end[1] == '\0'))) { + ret = bdi_set_min_ratio(bdi, ratio); + if (!ret) + ret = count; + } + return ret; +} +BDI_SHOW(min_ratio, bdi->min_ratio) + +static ssize_t max_ratio_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t count) +{ + struct backing_dev_info *bdi = dev_get_drvdata(dev); + char *end; + unsigned int ratio; + ssize_t ret = -EINVAL; + + ratio = simple_strtoul(buf, &end, 10); + if (*buf && (end[0] == '\0' || (end[0] == '\n' && end[1] == '\0'))) { + ret = bdi_set_max_ratio(bdi, ratio); + if (!ret) + ret = count; + } + return ret; +} +BDI_SHOW(max_ratio, bdi->max_ratio) + +#define __ATTR_RW(attr) __ATTR(attr, 0644, attr##_show, attr##_store) + +static struct device_attribute bdi_dev_attrs[] = { + __ATTR_RW(read_ahead_kb), + __ATTR_RO(reclaimable_kb), + __ATTR_RO(writeback_kb), + __ATTR_RO(dirty_kb), + __ATTR_RO(bdi_dirty_kb), + __ATTR_RW(min_ratio), + __ATTR_RW(max_ratio), + __ATTR_NULL, +}; + +static __init int bdi_class_init(void) +{ + bdi_class = class_create(THIS_MODULE, "bdi"); + bdi_class->dev_attrs = bdi_dev_attrs; + return 0; +} + +core_initcall(bdi_class_init); + +int bdi_register(struct backing_dev_info *bdi, struct device *parent, + const char *fmt, ...) +{ + char *name; + va_list args; + int ret = 0; + struct device *dev; + + va_start(args, fmt); + name = kvasprintf(GFP_KERNEL, fmt, args); + va_end(args); + + if (!name) + return -ENOMEM; + + dev = device_create(bdi_class, parent, MKDEV(0, 0), name); + if (IS_ERR(dev)) { + ret = PTR_ERR(dev); + goto exit; + } + + bdi->dev = dev; + dev_set_drvdata(bdi->dev, bdi); + +exit: + kfree(name); + return ret; +} +EXPORT_SYMBOL(bdi_register); + +int bdi_register_dev(struct backing_dev_info *bdi, dev_t dev) +{ + return bdi_register(bdi, NULL, "%u:%u", MAJOR(dev), MINOR(dev)); +} +EXPORT_SYMBOL(bdi_register_dev); + +void bdi_unregister(struct backing_dev_info *bdi) +{ + if (bdi->dev) { + device_unregister(bdi->dev); + bdi->dev = NULL; + } +} +EXPORT_SYMBOL(bdi_unregister); + +int bdi_init(struct backing_dev_info *bdi) +{ + int i; + int err; + + bdi->dev = NULL; + + bdi->min_ratio = 0; + bdi->max_ratio = 100; + bdi->max_prop_frac = PROP_FRAC_BASE; + + for (i = 0; i < NR_BDI_STAT_ITEMS; i++) { + err = percpu_counter_init_irq(&bdi->bdi_stat[i], 0); + if (err) + goto err; + } + + bdi->dirty_exceeded = 0; + err = prop_local_init_percpu(&bdi->completions); + + if (err) { +err: + while (i--) + percpu_counter_destroy(&bdi->bdi_stat[i]); + } + + return err; +} +EXPORT_SYMBOL(bdi_init); + +void bdi_destroy(struct backing_dev_info *bdi) +{ + int i; + + bdi_unregister(bdi); + + for (i = 0; i < NR_BDI_STAT_ITEMS; i++) + percpu_counter_destroy(&bdi->bdi_stat[i]); + + prop_local_destroy_percpu(&bdi->completions); +} +EXPORT_SYMBOL(bdi_destroy); static wait_queue_head_t congestion_wqh[2] = { __WAIT_QUEUE_HEAD_INITIALIZER(congestion_wqh[0]), @@ -55,31 +251,3 @@ long congestion_wait(int rw, long timeout) } EXPORT_SYMBOL(congestion_wait); -long congestion_wait_interruptible(int rw, long timeout) -{ - long ret; - DEFINE_WAIT(wait); - wait_queue_head_t *wqh = &congestion_wqh[rw]; - - prepare_to_wait(wqh, &wait, TASK_INTERRUPTIBLE); - if (signal_pending(current)) - ret = -ERESTARTSYS; - else - ret = io_schedule_timeout(timeout); - finish_wait(wqh, &wait); - return ret; -} -EXPORT_SYMBOL(congestion_wait_interruptible); - -/** - * congestion_end - wake up sleepers on a congested backing_dev_info - * @rw: READ or WRITE - */ -void congestion_end(int rw) -{ - wait_queue_head_t *wqh = &congestion_wqh[rw]; - - if (waitqueue_active(wqh)) - wake_up(wqh); -} -EXPORT_SYMBOL(congestion_end);