From d866d875f68fdeae63df334d291fe138dc636d96 Mon Sep 17 00:00:00 2001 From: Boaz Harrosh Date: Wed, 28 Sep 2011 14:43:09 +0300 Subject: ore/exofs: Change the type of the devices array (API change) In the pNFS obj-LD the device table at the layout level needs to point to a device_cache node, where it is possible and likely that many layouts will point to the same device-nodes. In Exofs we have a more orderly structure where we have a single array of devices that repeats twice for a round-robin view of the device table This patch moves to a model that can be used by the pNFS obj-LD where struct ore_components holds an array of ore_dev-pointers. (ore_dev is newly defined and contains a struct osd_dev *od member) Each pointer in the array of pointers will point to a bigger user-defined dev_struct. That can be accessed by use of the container_of macro. In Exofs an __alloc_dev_table() function allocates the ore_dev-pointers array as well as an exofs_dev array, in one allocation and does the addresses dance to set everything pointing correctly. It still keeps the double allocation trick for the inodes round-robin view of the table. The device table is always allocated dynamically, also for the single device case. So it is unconditionally freed at umount. Signed-off-by: Boaz Harrosh --- fs/exofs/super.c | 99 ++++++++++++++++++++++++++++++++++---------------------- 1 file changed, 61 insertions(+), 38 deletions(-) (limited to 'fs/exofs/super.c') diff --git a/fs/exofs/super.c b/fs/exofs/super.c index 90b4c526939..bce3686f0aa 100644 --- a/fs/exofs/super.c +++ b/fs/exofs/super.c @@ -431,17 +431,18 @@ static void _exofs_print_device(const char *msg, const char *dev_path, static void exofs_free_sbi(struct exofs_sb_info *sbi) { - while (sbi->oc.numdevs) { - int i = --sbi->oc.numdevs; - struct osd_dev *od = sbi->oc.ods[i]; + unsigned numdevs = sbi->oc.numdevs; + + while (numdevs) { + unsigned i = --numdevs; + struct osd_dev *od = ore_comp_dev(&sbi->oc, i); if (od) { - sbi->oc.ods[i] = NULL; + ore_comp_set_dev(&sbi->oc, i, NULL); osduld_put_device(od); } } - if (sbi->oc.ods != sbi->_min_one_dev) - kfree(sbi->oc.ods); + kfree(sbi->oc.ods); kfree(sbi); } @@ -468,7 +469,7 @@ static void exofs_put_super(struct super_block *sb) msecs_to_jiffies(100)); } - _exofs_print_device("Unmounting", NULL, sbi->oc.ods[0], + _exofs_print_device("Unmounting", NULL, ore_comp_dev(&sbi->oc, 0), sbi->one_comp.obj.partition); bdi_destroy(&sbi->bdi); @@ -592,12 +593,40 @@ static int exofs_devs_2_odi(struct exofs_dt_device_info *dt_dev, return !(odi->systemid_len || odi->osdname_len); } +int __alloc_dev_table(struct exofs_sb_info *sbi, unsigned numdevs, + struct exofs_dev **peds) +{ + struct __alloc_ore_devs_and_exofs_devs { + /* Twice bigger table: See exofs_init_comps() and comment at + * exofs_read_lookup_dev_table() + */ + struct ore_dev *oreds[numdevs * 2 - 1]; + struct exofs_dev eds[numdevs]; + } *aoded; + struct exofs_dev *eds; + unsigned i; + + aoded = kzalloc(sizeof(*aoded), GFP_KERNEL); + if (unlikely(!aoded)) { + EXOFS_ERR("ERROR: faild allocating Device array[%d]\n", + numdevs); + return -ENOMEM; + } + + sbi->oc.ods = aoded->oreds; + *peds = eds = aoded->eds; + for (i = 0; i < numdevs; ++i) + aoded->oreds[i] = &eds[i].ored; + return 0; +} + static int exofs_read_lookup_dev_table(struct exofs_sb_info *sbi, struct osd_dev *fscb_od, unsigned table_count) { struct ore_comp comp; struct exofs_device_table *dt; + struct exofs_dev *eds; unsigned table_bytes = table_count * sizeof(dt->dt_dev_table[0]) + sizeof(*dt); unsigned numdevs, i; @@ -634,20 +663,16 @@ static int exofs_read_lookup_dev_table(struct exofs_sb_info *sbi, if (unlikely(ret)) goto out; - if (likely(numdevs > 1)) { - unsigned size = numdevs * sizeof(sbi->oc.ods[0]); - - /* Twice bigger table: See exofs_init_comps() and below - * comment - */ - sbi->oc.ods = kzalloc(size + size - 1, GFP_KERNEL); - if (unlikely(!sbi->oc.ods)) { - EXOFS_ERR("ERROR: faild allocating Device array[%d]\n", - numdevs); - ret = -ENOMEM; - goto out; - } - } + ret = __alloc_dev_table(sbi, numdevs, &eds); + if (unlikely(ret)) + goto out; + /* exofs round-robins the device table view according to inode + * number. We hold a: twice bigger table hence inodes can point + * to any device and have a sequential view of the table + * starting at this device. See exofs_init_comps() + */ + memcpy(&sbi->oc.ods[numdevs], &sbi->oc.ods[0], + (numdevs - 1) * sizeof(sbi->oc.ods[0])); for (i = 0; i < numdevs; i++) { struct exofs_fscb fscb; @@ -663,12 +688,15 @@ static int exofs_read_lookup_dev_table(struct exofs_sb_info *sbi, printk(KERN_NOTICE "Add device[%d]: osd_name-%s\n", i, odi.osdname); + /* the exofs id is currently the table index */ + eds[i].did = i; + /* On all devices the device table is identical. The user can * specify any one of the participating devices on the command * line. We always keep them in device-table order. */ if (fscb_od && osduld_device_same(fscb_od, &odi)) { - sbi->oc.ods[i] = fscb_od; + eds[i].ored.od = fscb_od; ++sbi->oc.numdevs; fscb_od = NULL; continue; @@ -682,7 +710,7 @@ static int exofs_read_lookup_dev_table(struct exofs_sb_info *sbi, goto out; } - sbi->oc.ods[i] = od; + eds[i].ored.od = od; ++sbi->oc.numdevs; /* Read the fscb of the other devices to make sure the FS @@ -705,21 +733,10 @@ static int exofs_read_lookup_dev_table(struct exofs_sb_info *sbi, out: kfree(dt); - if (likely(!ret)) { - unsigned numdevs = sbi->oc.numdevs; - - if (unlikely(fscb_od)) { + if (unlikely(fscb_od && !ret)) { EXOFS_ERR("ERROR: Bad device-table container device not present\n"); osduld_put_device(fscb_od); return -EINVAL; - } - /* exofs round-robins the device table view according to inode - * number. We hold a: twice bigger table hence inodes can point - * to any device and have a sequential view of the table - * starting at this device. See exofs_init_comps() - */ - for (i = 0; i < numdevs - 1; ++i) - sbi->oc.ods[i + numdevs] = sbi->oc.ods[i]; } return ret; } @@ -773,7 +790,6 @@ static int exofs_fill_super(struct super_block *sb, void *data, int silent) sbi->oc.numdevs = 1; sbi->oc.single_comp = EC_SINGLE_COMP; sbi->oc.comps = &sbi->one_comp; - sbi->oc.ods = sbi->_min_one_dev; /* fill in some other data by hand */ memset(sb->s_id, 0, sizeof(sb->s_id)); @@ -822,7 +838,13 @@ static int exofs_fill_super(struct super_block *sb, void *data, int silent) if (unlikely(ret)) goto free_sbi; } else { - sbi->oc.ods[0] = od; + struct exofs_dev *eds; + + ret = __alloc_dev_table(sbi, 1, &eds); + if (unlikely(ret)) + goto free_sbi; + + ore_comp_set_dev(&sbi->oc, 0, od); } __sbi_read_stats(sbi); @@ -862,7 +884,8 @@ static int exofs_fill_super(struct super_block *sb, void *data, int silent) goto free_sbi; } - _exofs_print_device("Mounting", opts->dev_name, sbi->oc.ods[0], + _exofs_print_device("Mounting", opts->dev_name, + ore_comp_dev(&sbi->oc, 0), sbi->one_comp.obj.partition); return 0; -- cgit v1.2.3