diff options
| author | Stefan Roesch <shr@devkernel.io> | 2022-11-18 16:52:03 -0800 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2022-11-30 15:59:04 -0800 |
| commit | c56e049a5e401a177c7c9b39a3bcc973ff5cec0b (patch) | |
| tree | b7cffffc02de6eba8280a57fbe9fec107fad1244 | |
| parent | 1bf27e98d26d1e62166a456ef17460be085cbe0b (diff) | |
mm: add knob /sys/class/bdi/<bdi>/max_bytes
This adds the new knob max_bytes to specify a dirty memory limit for the
corresponding bdi. The specified bytes value is converted to a ratio.
Link: https://lkml.kernel.org/r/20221119005215.3052436-9-shr@devkernel.io
Signed-off-by: Stefan Roesch <shr@devkernel.io>
Cc: Chris Mason <clm@meta.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | mm/backing-dev.c | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/mm/backing-dev.c b/mm/backing-dev.c index 90fa517123dc..95d3229fc81f 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -199,6 +199,34 @@ static ssize_t max_ratio_store(struct device *dev, } BDI_SHOW(max_ratio, bdi->max_ratio / BDI_RATIO_SCALE) +static ssize_t max_bytes_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct backing_dev_info *bdi = dev_get_drvdata(dev); + + return sysfs_emit(buf, "%llu\n", bdi_get_max_bytes(bdi)); +} + +static ssize_t max_bytes_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t count) +{ + struct backing_dev_info *bdi = dev_get_drvdata(dev); + u64 bytes; + ssize_t ret; + + ret = kstrtoull(buf, 10, &bytes); + if (ret < 0) + return ret; + + ret = bdi_set_max_bytes(bdi, bytes); + if (!ret) + ret = count; + + return ret; +} +DEVICE_ATTR_RW(max_bytes); + static ssize_t stable_pages_required_show(struct device *dev, struct device_attribute *attr, char *buf) @@ -241,6 +269,7 @@ static struct attribute *bdi_dev_attrs[] = { &dev_attr_read_ahead_kb.attr, &dev_attr_min_ratio.attr, &dev_attr_max_ratio.attr, + &dev_attr_max_bytes.attr, &dev_attr_stable_pages_required.attr, &dev_attr_strict_limit.attr, NULL, |