From: Timofey Titovets <[email protected]>
This add supporting of autochange count of zram devices on demand, like
loop devices;
This working by following rules:
- Always save minimum devices count specified by num_device (can be
specified while kernel module loading)
- if last device already using add new device;
- if last and prelast devices is free - delete last zram device;
Signed-off-by: Timofey Titovets <[email protected]>
Please pull from:
https://github.com/Nefelim4ag/linux.git
---
Tested on 3.15.5-2-ARCH, can be applied on any kernel version
after this patch 'zram: add LZ4 compression support' -
https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/commit/?id=6e76668e415adf799839f0ab205142ad7002d260
---
drivers/block/zram/zram_drv.c | 65
++++++++++++++++++++++++++++++++++++++++---
1 file changed, 61 insertions(+), 4 deletions(-)
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 089e72c..d0a3055 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -42,6 +42,10 @@ static const char *default_compressor = "lzo";
/* Module params (documentation at end) */
static unsigned int num_devices = 1;
+static unsigned int last_created_dev = 1;
+
+static void zram_add_dev(void);
+static void zram_del_dev(void);
#define ZRAM_ATTR_RO(name) \
static ssize_t zram_attr_##name##_show(struct device *d, \
@@ -168,6 +172,7 @@ static ssize_t comp_algorithm_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t len)
{
struct zram *zram = dev_to_zram(dev);
+
down_write(&zram->init_lock);
if (init_done(zram)) {
up_write(&zram->init_lock);
@@ -239,6 +244,7 @@ static struct zram_meta *zram_meta_alloc(u64 disksize)
{
size_t num_pages;
struct zram_meta *meta = kmalloc(sizeof(*meta), GFP_KERNEL);
+
if (!meta)
goto out;
@@ -374,6 +380,7 @@ static int zram_bvec_read(struct zram *zram, struct
bio_vec *bvec,
struct page *page;
unsigned char *user_mem, *uncmem = NULL;
struct zram_meta *meta = zram->meta;
+
page = bvec->bv_page;
read_lock(&meta->tb_lock);
@@ -607,6 +614,7 @@ static void zram_reset_device(struct zram *zram,
bool reset_capacity)
/* Free all pages that are still in this zram device */
for (index = 0; index < zram->disksize >> PAGE_SHIFT; index++) {
unsigned long handle = meta->table[index].handle;
+
if (!handle)
continue;
@@ -668,6 +676,7 @@ static ssize_t disksize_store(struct device *dev,
set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT);
revalidate_disk(zram->disk);
up_write(&zram->init_lock);
+ zram_add_dev();
return len;
out_destroy_comp:
@@ -712,6 +721,7 @@ static ssize_t reset_store(struct device *dev,
bdput(bdev);
zram_reset_device(zram, true);
+ zram_del_dev();
return len;
out:
@@ -954,6 +964,51 @@ static void destroy_device(struct zram *zram)
blk_cleanup_queue(zram->queue);
}
+/* remove last free device, if last and prelast dev a free */
+static void zram_del_dev(void)
+{
+ if (last_created_dev < num_devices)
+ return;
+
+ if (zram_devices[last_created_dev].disksize == 0 &&
+ zram_devices[last_created_dev-1].disksize == 0
+ ) {
+ destroy_device(&zram_devices[last_created_dev]);
+ last_created_dev--;
+ pr_info("Deleted zram%u device\n", last_created_dev);
+ }
+}
+
+/* Auto add empty zram device, if last device in use */
+static void zram_add_dev(void)
+{
+ int ret;
+
+ if (last_created_dev+1 > max_num_devices) {
+ pr_warn("Can't add zram%u, max device number reached\n",
+ num_devices);
+ last_created_dev--;
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (&zram_devices[last_created_dev].disksize > 0) {
+ last_created_dev++;
+ ret = create_device(&zram_devices[last_created_dev],
+ last_created_dev);
+ if (ret)
+ goto free;
+ pr_info("Created zram%u device\n", last_created_dev);
+ }
+
+ return;
+
+free:
+ destroy_device(&zram_devices[last_created_dev]);
+ last_created_dev--;
+out:;
+}
+
static int __init zram_init(void)
{
int ret, dev_id;
@@ -972,18 +1027,20 @@ static int __init zram_init(void)
goto out;
}
- /* Allocate the device array and initialize each one */
- zram_devices = kzalloc(num_devices * sizeof(struct zram), GFP_KERNEL);
+ /* Allocate the device array */
+ zram_devices = kcalloc(max_num_devices, sizeof(struct zram), GFP_KERNEL);
if (!zram_devices) {
ret = -ENOMEM;
goto unregister;
}
+ /* Initialise zram{0..num_devices} */
for (dev_id = 0; dev_id < num_devices; dev_id++) {
ret = create_device(&zram_devices[dev_id], dev_id);
if (ret)
goto free_devices;
}
+ last_created_dev = num_devices-1;
pr_info("Created %u device(s) ...\n", num_devices);
@@ -1004,7 +1061,7 @@ static void __exit zram_exit(void)
int i;
struct zram *zram;
- for (i = 0; i < num_devices; i++) {
+ for (i = 0; i < last_created_dev+1; i++) {
zram = &zram_devices[i];
destroy_device(zram);
@@ -1025,7 +1082,7 @@ module_init(zram_init);
module_exit(zram_exit);
module_param(num_devices, uint, 0);
-MODULE_PARM_DESC(num_devices, "Number of zram devices");
+MODULE_PARM_DESC(num_devices, "Number of pre created zram devices");
MODULE_LICENSE("Dual BSD/GPL");
MODULE_AUTHOR("Nitin Gupta <[email protected]>");
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
On 07/17/2014 11:32 AM, Timofey Titovets wrote:
> From: Timofey Titovets <[email protected]>
>
> This add supporting of autochange count of zram devices on demand,
> like loop devices; This working by following rules: - Always save
> minimum devices count specified by num_device (can be specified
> while kernel module loading) - if last device already using add new
> device; - if last and prelast devices is free - delete last zram
> device;
>
Hi Timofey,
Your patch change zram behaviour. Please describe what changes from
the user point of view and update Documentation/blockdev/zram.txt
accordingly.
> Signed-off-by: Timofey Titovets <[email protected]>
>
> Please pull from: https://github.com/Nefelim4ag/linux.git ---
> Tested on 3.15.5-2-ARCH, can be applied on any kernel version after
> this patch 'zram: add LZ4 compression support' -
> https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/commit/?id=6e76668e415adf799839f0ab205142ad7002d260
>
> --- drivers/block/zram/zram_drv.c | 65
> ++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 61
> insertions(+), 4 deletions(-)
>
> diff --git a/drivers/block/zram/zram_drv.c
> b/drivers/block/zram/zram_drv.c index 089e72c..d0a3055 100644 ---
> a/drivers/block/zram/zram_drv.c +++
> b/drivers/block/zram/zram_drv.c @@ -42,6 +42,10 @@ static const
> char *default_compressor = "lzo";
>
> /* Module params (documentation at end) */ static unsigned int
> num_devices = 1; +static unsigned int last_created_dev = 1; +
> +static void zram_add_dev(void); +static void zram_del_dev(void);
>
> #define ZRAM_ATTR_RO(name) \ static ssize_t
> zram_attr_##name##_show(struct device *d, \ @@ -168,6 +172,7
> @@ static ssize_t comp_algorithm_store(struct device *dev, struct
> device_attribute *attr, const char *buf, size_t len) { struct zram
> *zram = dev_to_zram(dev); + down_write(&zram->init_lock); if
> (init_done(zram)) { up_write(&zram->init_lock); @@ -239,6 +244,7 @@
> static struct zram_meta *zram_meta_alloc(u64 disksize) { size_t
> num_pages; struct zram_meta *meta = kmalloc(sizeof(*meta),
> GFP_KERNEL); + if (!meta) goto out;
>
> @@ -374,6 +380,7 @@ static int zram_bvec_read(struct zram *zram,
> struct bio_vec *bvec, struct page *page; unsigned char *user_mem,
> *uncmem = NULL; struct zram_meta *meta = zram->meta; + page =
> bvec->bv_page;
>
> read_lock(&meta->tb_lock); @@ -607,6 +614,7 @@ static void
> zram_reset_device(struct zram *zram, bool reset_capacity) /* Free
> all pages that are still in this zram device */ for (index = 0;
> index < zram->disksize >> PAGE_SHIFT; index++) { unsigned long
> handle = meta->table[index].handle; + if (!handle) continue;
>
> @@ -668,6 +676,7 @@ static ssize_t disksize_store(struct device
> *dev, set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT);
> revalidate_disk(zram->disk); up_write(&zram->init_lock); +
> zram_add_dev(); return len;
>
> out_destroy_comp: @@ -712,6 +721,7 @@ static ssize_t
> reset_store(struct device *dev, bdput(bdev);
>
> zram_reset_device(zram, true); + zram_del_dev(); return len;
>
> out: @@ -954,6 +964,51 @@ static void destroy_device(struct zram
> *zram) blk_cleanup_queue(zram->queue); }
>
> +/* remove last free device, if last and prelast dev a free */
> +static void zram_del_dev(void) +{ + if (last_created_dev <
> num_devices) + return; + + if
> (zram_devices[last_created_dev].disksize == 0 && +
> zram_devices[last_created_dev-1].disksize == 0 + ) { +
> destroy_device(&zram_devices[last_created_dev]); +
> last_created_dev--; + pr_info("Deleted zram%u device\n",
> last_created_dev); + } +} + +/* Auto add empty zram device, if
> last device in use */ +static void zram_add_dev(void) +{ + int
> ret; + + if (last_created_dev+1 > max_num_devices) { +
> pr_warn("Can't add zram%u, max device number reached\n", +
> num_devices); + last_created_dev--; + ret = -EINVAL;
Why do you set ret to EINVAL here? It's never used.
> + goto out;
That label is useless. Just use return.
> + } + + if (&zram_devices[last_created_dev].disksize > 0) { +
> last_created_dev++; + ret =
> create_device(&zram_devices[last_created_dev], +
> last_created_dev); + if (ret) + goto free;
If ret is only used to test that create_device() succeeded, then we
can get rid of that variable altogether.
Thanks,
Jerome
> + pr_info("Created zram%u device\n", last_created_dev); +
> } + + return; + +free: +
> destroy_device(&zram_devices[last_created_dev]); +
> last_created_dev--; +out:; +} + static int __init zram_init(void)
> { int ret, dev_id; @@ -972,18 +1027,20 @@ static int __init
> zram_init(void) goto out; }
>
> - /* Allocate the device array and initialize each one */ -
> zram_devices = kzalloc(num_devices * sizeof(struct zram),
> GFP_KERNEL); + /* Allocate the device array */ + zram_devices
> = kcalloc(max_num_devices, sizeof(struct zram), GFP_KERNEL); if
> (!zram_devices) { ret = -ENOMEM; goto unregister; }
>
> + /* Initialise zram{0..num_devices} */ for (dev_id = 0; dev_id
> < num_devices; dev_id++) { ret =
> create_device(&zram_devices[dev_id], dev_id); if (ret) goto
> free_devices; } + last_created_dev = num_devices-1;
>
> pr_info("Created %u device(s) ...\n", num_devices);
>
> @@ -1004,7 +1061,7 @@ static void __exit zram_exit(void) int i;
> struct zram *zram;
>
> - for (i = 0; i < num_devices; i++) { + for (i = 0; i <
> last_created_dev+1; i++) { zram = &zram_devices[i];
>
> destroy_device(zram); @@ -1025,7 +1082,7 @@
> module_init(zram_init); module_exit(zram_exit);
>
> module_param(num_devices, uint, 0); -MODULE_PARM_DESC(num_devices,
> "Number of zram devices"); +MODULE_PARM_DESC(num_devices, "Number
> of pre created zram devices");
>
> MODULE_LICENSE("Dual BSD/GPL"); MODULE_AUTHOR("Nitin Gupta
> <[email protected]>");
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Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/
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Thanks for comments, i will fix what you say and split patches one for
code and one for Documentation.
After, i will resend patch set
On 07/17/2014 01:09 PM, Jerome Marchand wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
>
> On 07/17/2014 11:32 AM, Timofey Titovets wrote:
>> From: Timofey Titovets <[email protected]>
>>
>> This add supporting of autochange count of zram devices on demand,
>> like loop devices; This working by following rules: - Always save
>> minimum devices count specified by num_device (can be specified
>> while kernel module loading) - if last device already using add new
>> device; - if last and prelast devices is free - delete last zram
>> device;
>>
>
> Hi Timofey,
>
> Your patch change zram behaviour. Please describe what changes from
> the user point of view and update Documentation/blockdev/zram.txt
> accordingly.
>
>> Signed-off-by: Timofey Titovets <[email protected]>
>>
>> Please pull from: https://github.com/Nefelim4ag/linux.git ---
>> Tested on 3.15.5-2-ARCH, can be applied on any kernel version after
>> this patch 'zram: add LZ4 compression support' -
>> https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/commit/?id=6e76668e415adf799839f0ab205142ad7002d260
>>
>> --- drivers/block/zram/zram_drv.c | 65
>> ++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 61
>> insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/block/zram/zram_drv.c
>> b/drivers/block/zram/zram_drv.c index 089e72c..d0a3055 100644 ---
>> a/drivers/block/zram/zram_drv.c +++
>> b/drivers/block/zram/zram_drv.c @@ -42,6 +42,10 @@ static const
>> char *default_compressor = "lzo";
>>
>> /* Module params (documentation at end) */ static unsigned int
>> num_devices = 1; +static unsigned int last_created_dev = 1; +
>> +static void zram_add_dev(void); +static void zram_del_dev(void);
>>
>> #define ZRAM_ATTR_RO(name) \ static ssize_t
>> zram_attr_##name##_show(struct device *d, \ @@ -168,6 +172,7
>> @@ static ssize_t comp_algorithm_store(struct device *dev, struct
>> device_attribute *attr, const char *buf, size_t len) { struct zram
>> *zram = dev_to_zram(dev); + down_write(&zram->init_lock); if
>> (init_done(zram)) { up_write(&zram->init_lock); @@ -239,6 +244,7 @@
>> static struct zram_meta *zram_meta_alloc(u64 disksize) { size_t
>> num_pages; struct zram_meta *meta = kmalloc(sizeof(*meta),
>> GFP_KERNEL); + if (!meta) goto out;
>>
>> @@ -374,6 +380,7 @@ static int zram_bvec_read(struct zram *zram,
>> struct bio_vec *bvec, struct page *page; unsigned char *user_mem,
>> *uncmem = NULL; struct zram_meta *meta = zram->meta; + page =
>> bvec->bv_page;
>>
>> read_lock(&meta->tb_lock); @@ -607,6 +614,7 @@ static void
>> zram_reset_device(struct zram *zram, bool reset_capacity) /* Free
>> all pages that are still in this zram device */ for (index = 0;
>> index < zram->disksize >> PAGE_SHIFT; index++) { unsigned long
>> handle = meta->table[index].handle; + if (!handle) continue;
>>
>> @@ -668,6 +676,7 @@ static ssize_t disksize_store(struct device
>> *dev, set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT);
>> revalidate_disk(zram->disk); up_write(&zram->init_lock); +
>> zram_add_dev(); return len;
>>
>> out_destroy_comp: @@ -712,6 +721,7 @@ static ssize_t
>> reset_store(struct device *dev, bdput(bdev);
>>
>> zram_reset_device(zram, true); + zram_del_dev(); return len;
>>
>> out: @@ -954,6 +964,51 @@ static void destroy_device(struct zram
>> *zram) blk_cleanup_queue(zram->queue); }
>>
>> +/* remove last free device, if last and prelast dev a free */
>> +static void zram_del_dev(void) +{ + if (last_created_dev <
>> num_devices) + return; + + if
>> (zram_devices[last_created_dev].disksize == 0 && +
>> zram_devices[last_created_dev-1].disksize == 0 + ) { +
>> destroy_device(&zram_devices[last_created_dev]); +
>> last_created_dev--; + pr_info("Deleted zram%u device\n",
>> last_created_dev); + } +} + +/* Auto add empty zram device, if
>> last device in use */ +static void zram_add_dev(void) +{ + int
>> ret; + + if (last_created_dev+1 > max_num_devices) { +
>> pr_warn("Can't add zram%u, max device number reached\n", +
>> num_devices); + last_created_dev--; + ret = -EINVAL;
>
> Why do you set ret to EINVAL here? It's never used.
>
>> + goto out;
>
> That label is useless. Just use return.
>
>> + } + + if (&zram_devices[last_created_dev].disksize > 0) { +
>> last_created_dev++; + ret =
>> create_device(&zram_devices[last_created_dev], +
>> last_created_dev); + if (ret) + goto free;
>
> If ret is only used to test that create_device() succeeded, then we
> can get rid of that variable altogether.
>
> Thanks,
> Jerome
>
>> + pr_info("Created zram%u device\n", last_created_dev); +
>> } + + return; + +free: +
>> destroy_device(&zram_devices[last_created_dev]); +
>> last_created_dev--; +out:; +} + static int __init zram_init(void)
>> { int ret, dev_id; @@ -972,18 +1027,20 @@ static int __init
>> zram_init(void) goto out; }
>>
>> - /* Allocate the device array and initialize each one */ -
>> zram_devices = kzalloc(num_devices * sizeof(struct zram),
>> GFP_KERNEL); + /* Allocate the device array */ + zram_devices
>> = kcalloc(max_num_devices, sizeof(struct zram), GFP_KERNEL); if
>> (!zram_devices) { ret = -ENOMEM; goto unregister; }
>>
>> + /* Initialise zram{0..num_devices} */ for (dev_id = 0; dev_id
>> < num_devices; dev_id++) { ret =
>> create_device(&zram_devices[dev_id], dev_id); if (ret) goto
>> free_devices; } + last_created_dev = num_devices-1;
>>
>> pr_info("Created %u device(s) ...\n", num_devices);
>>
>> @@ -1004,7 +1061,7 @@ static void __exit zram_exit(void) int i;
>> struct zram *zram;
>>
>> - for (i = 0; i < num_devices; i++) { + for (i = 0; i <
>> last_created_dev+1; i++) { zram = &zram_devices[i];
>>
>> destroy_device(zram); @@ -1025,7 +1082,7 @@
>> module_init(zram_init); module_exit(zram_exit);
>>
>> module_param(num_devices, uint, 0); -MODULE_PARM_DESC(num_devices,
>> "Number of zram devices"); +MODULE_PARM_DESC(num_devices, "Number
>> of pre created zram devices");
>>
>> MODULE_LICENSE("Dual BSD/GPL"); MODULE_AUTHOR("Nitin Gupta
>> <[email protected]>");
>
> -----BEGIN PGP SIGNATURE-----
> Version: GnuPG v1
> Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/
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>