| |
| /* |
| rbd.c -- Export ceph rados objects as a Linux block device |
| |
| |
| based on drivers/block/osdblk.c: |
| |
| Copyright 2009 Red Hat, Inc. |
| |
| This program is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation. |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program; see the file COPYING. If not, write to |
| the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. |
| |
| |
| |
| For usage instructions, please refer to: |
| |
| Documentation/ABI/testing/sysfs-bus-rbd |
| |
| */ |
| |
| #include <linux/ceph/libceph.h> |
| #include <linux/ceph/osd_client.h> |
| #include <linux/ceph/mon_client.h> |
| #include <linux/ceph/decode.h> |
| #include <linux/parser.h> |
| #include <linux/bsearch.h> |
| |
| #include <linux/kernel.h> |
| #include <linux/device.h> |
| #include <linux/module.h> |
| #include <linux/blk-mq.h> |
| #include <linux/fs.h> |
| #include <linux/blkdev.h> |
| #include <linux/slab.h> |
| #include <linux/idr.h> |
| #include <linux/workqueue.h> |
| |
| #include "rbd_types.h" |
| |
| #define RBD_DEBUG /* Activate rbd_assert() calls */ |
| |
| /* |
| * The basic unit of block I/O is a sector. It is interpreted in a |
| * number of contexts in Linux (blk, bio, genhd), but the default is |
| * universally 512 bytes. These symbols are just slightly more |
| * meaningful than the bare numbers they represent. |
| */ |
| #define SECTOR_SHIFT 9 |
| #define SECTOR_SIZE (1ULL << SECTOR_SHIFT) |
| |
| /* |
| * Increment the given counter and return its updated value. |
| * If the counter is already 0 it will not be incremented. |
| * If the counter is already at its maximum value returns |
| * -EINVAL without updating it. |
| */ |
| static int atomic_inc_return_safe(atomic_t *v) |
| { |
| unsigned int counter; |
| |
| counter = (unsigned int)__atomic_add_unless(v, 1, 0); |
| if (counter <= (unsigned int)INT_MAX) |
| return (int)counter; |
| |
| atomic_dec(v); |
| |
| return -EINVAL; |
| } |
| |
| /* Decrement the counter. Return the resulting value, or -EINVAL */ |
| static int atomic_dec_return_safe(atomic_t *v) |
| { |
| int counter; |
| |
| counter = atomic_dec_return(v); |
| if (counter >= 0) |
| return counter; |
| |
| atomic_inc(v); |
| |
| return -EINVAL; |
| } |
| |
| #define RBD_DRV_NAME "rbd" |
| |
| #define RBD_MINORS_PER_MAJOR 256 |
| #define RBD_SINGLE_MAJOR_PART_SHIFT 4 |
| |
| #define RBD_MAX_PARENT_CHAIN_LEN 16 |
| |
| #define RBD_SNAP_DEV_NAME_PREFIX "snap_" |
| #define RBD_MAX_SNAP_NAME_LEN \ |
| (NAME_MAX - (sizeof (RBD_SNAP_DEV_NAME_PREFIX) - 1)) |
| |
| #define RBD_MAX_SNAP_COUNT 510 /* allows max snapc to fit in 4KB */ |
| |
| #define RBD_SNAP_HEAD_NAME "-" |
| |
| #define BAD_SNAP_INDEX U32_MAX /* invalid index into snap array */ |
| |
| /* This allows a single page to hold an image name sent by OSD */ |
| #define RBD_IMAGE_NAME_LEN_MAX (PAGE_SIZE - sizeof (__le32) - 1) |
| #define RBD_IMAGE_ID_LEN_MAX 64 |
| |
| #define RBD_OBJ_PREFIX_LEN_MAX 64 |
| |
| /* Feature bits */ |
| |
| #define RBD_FEATURE_LAYERING (1<<0) |
| #define RBD_FEATURE_STRIPINGV2 (1<<1) |
| #define RBD_FEATURES_ALL \ |
| (RBD_FEATURE_LAYERING | RBD_FEATURE_STRIPINGV2) |
| |
| /* Features supported by this (client software) implementation. */ |
| |
| #define RBD_FEATURES_SUPPORTED (RBD_FEATURES_ALL) |
| |
| /* |
| * An RBD device name will be "rbd#", where the "rbd" comes from |
| * RBD_DRV_NAME above, and # is a unique integer identifier. |
| * MAX_INT_FORMAT_WIDTH is used in ensuring DEV_NAME_LEN is big |
| * enough to hold all possible device names. |
| */ |
| #define DEV_NAME_LEN 32 |
| #define MAX_INT_FORMAT_WIDTH ((5 * sizeof (int)) / 2 + 1) |
| |
| /* |
| * block device image metadata (in-memory version) |
| */ |
| struct rbd_image_header { |
| /* These six fields never change for a given rbd image */ |
| char *object_prefix; |
| __u8 obj_order; |
| __u8 crypt_type; |
| __u8 comp_type; |
| u64 stripe_unit; |
| u64 stripe_count; |
| u64 features; /* Might be changeable someday? */ |
| |
| /* The remaining fields need to be updated occasionally */ |
| u64 image_size; |
| struct ceph_snap_context *snapc; |
| char *snap_names; /* format 1 only */ |
| u64 *snap_sizes; /* format 1 only */ |
| }; |
| |
| /* |
| * An rbd image specification. |
| * |
| * The tuple (pool_id, image_id, snap_id) is sufficient to uniquely |
| * identify an image. Each rbd_dev structure includes a pointer to |
| * an rbd_spec structure that encapsulates this identity. |
| * |
| * Each of the id's in an rbd_spec has an associated name. For a |
| * user-mapped image, the names are supplied and the id's associated |
| * with them are looked up. For a layered image, a parent image is |
| * defined by the tuple, and the names are looked up. |
| * |
| * An rbd_dev structure contains a parent_spec pointer which is |
| * non-null if the image it represents is a child in a layered |
| * image. This pointer will refer to the rbd_spec structure used |
| * by the parent rbd_dev for its own identity (i.e., the structure |
| * is shared between the parent and child). |
| * |
| * Since these structures are populated once, during the discovery |
| * phase of image construction, they are effectively immutable so |
| * we make no effort to synchronize access to them. |
| * |
| * Note that code herein does not assume the image name is known (it |
| * could be a null pointer). |
| */ |
| struct rbd_spec { |
| u64 pool_id; |
| const char *pool_name; |
| |
| const char *image_id; |
| const char *image_name; |
| |
| u64 snap_id; |
| const char *snap_name; |
| |
| struct kref kref; |
| }; |
| |
| /* |
| * an instance of the client. multiple devices may share an rbd client. |
| */ |
| struct rbd_client { |
| struct ceph_client *client; |
| struct kref kref; |
| struct list_head node; |
| }; |
| |
| struct rbd_img_request; |
| typedef void (*rbd_img_callback_t)(struct rbd_img_request *); |
| |
| #define BAD_WHICH U32_MAX /* Good which or bad which, which? */ |
| |
| struct rbd_obj_request; |
| typedef void (*rbd_obj_callback_t)(struct rbd_obj_request *); |
| |
| enum obj_request_type { |
| OBJ_REQUEST_NODATA, OBJ_REQUEST_BIO, OBJ_REQUEST_PAGES |
| }; |
| |
| enum obj_operation_type { |
| OBJ_OP_WRITE, |
| OBJ_OP_READ, |
| OBJ_OP_DISCARD, |
| }; |
| |
| enum obj_req_flags { |
| OBJ_REQ_DONE, /* completion flag: not done = 0, done = 1 */ |
| OBJ_REQ_IMG_DATA, /* object usage: standalone = 0, image = 1 */ |
| OBJ_REQ_KNOWN, /* EXISTS flag valid: no = 0, yes = 1 */ |
| OBJ_REQ_EXISTS, /* target exists: no = 0, yes = 1 */ |
| }; |
| |
| struct rbd_obj_request { |
| const char *object_name; |
| u64 offset; /* object start byte */ |
| u64 length; /* bytes from offset */ |
| unsigned long flags; |
| |
| /* |
| * An object request associated with an image will have its |
| * img_data flag set; a standalone object request will not. |
| * |
| * A standalone object request will have which == BAD_WHICH |
| * and a null obj_request pointer. |
| * |
| * An object request initiated in support of a layered image |
| * object (to check for its existence before a write) will |
| * have which == BAD_WHICH and a non-null obj_request pointer. |
| * |
| * Finally, an object request for rbd image data will have |
| * which != BAD_WHICH, and will have a non-null img_request |
| * pointer. The value of which will be in the range |
| * 0..(img_request->obj_request_count-1). |
| */ |
| union { |
| struct rbd_obj_request *obj_request; /* STAT op */ |
| struct { |
| struct rbd_img_request *img_request; |
| u64 img_offset; |
| /* links for img_request->obj_requests list */ |
| struct list_head links; |
| }; |
| }; |
| u32 which; /* posn image request list */ |
| |
| enum obj_request_type type; |
| union { |
| struct bio *bio_list; |
| struct { |
| struct page **pages; |
| u32 page_count; |
| }; |
| }; |
| struct page **copyup_pages; |
| u32 copyup_page_count; |
| |
| struct ceph_osd_request *osd_req; |
| |
| u64 xferred; /* bytes transferred */ |
| int result; |
| |
| rbd_obj_callback_t callback; |
| struct completion completion; |
| |
| struct kref kref; |
| }; |
| |
| enum img_req_flags { |
| IMG_REQ_WRITE, /* I/O direction: read = 0, write = 1 */ |
| IMG_REQ_CHILD, /* initiator: block = 0, child image = 1 */ |
| IMG_REQ_LAYERED, /* ENOENT handling: normal = 0, layered = 1 */ |
| IMG_REQ_DISCARD, /* discard: normal = 0, discard request = 1 */ |
| }; |
| |
| struct rbd_img_request { |
| struct rbd_device *rbd_dev; |
| u64 offset; /* starting image byte offset */ |
| u64 length; /* byte count from offset */ |
| unsigned long flags; |
| union { |
| u64 snap_id; /* for reads */ |
| struct ceph_snap_context *snapc; /* for writes */ |
| }; |
| union { |
| struct request *rq; /* block request */ |
| struct rbd_obj_request *obj_request; /* obj req initiator */ |
| }; |
| struct page **copyup_pages; |
| u32 copyup_page_count; |
| spinlock_t completion_lock;/* protects next_completion */ |
| u32 next_completion; |
| rbd_img_callback_t callback; |
| u64 xferred;/* aggregate bytes transferred */ |
| int result; /* first nonzero obj_request result */ |
| |
| u32 obj_request_count; |
| struct list_head obj_requests; /* rbd_obj_request structs */ |
| |
| struct kref kref; |
| }; |
| |
| #define for_each_obj_request(ireq, oreq) \ |
| list_for_each_entry(oreq, &(ireq)->obj_requests, links) |
| #define for_each_obj_request_from(ireq, oreq) \ |
| list_for_each_entry_from(oreq, &(ireq)->obj_requests, links) |
| #define for_each_obj_request_safe(ireq, oreq, n) \ |
| list_for_each_entry_safe_reverse(oreq, n, &(ireq)->obj_requests, links) |
| |
| struct rbd_mapping { |
| u64 size; |
| u64 features; |
| bool read_only; |
| }; |
| |
| /* |
| * a single device |
| */ |
| struct rbd_device { |
| int dev_id; /* blkdev unique id */ |
| |
| int major; /* blkdev assigned major */ |
| int minor; |
| struct gendisk *disk; /* blkdev's gendisk and rq */ |
| |
| u32 image_format; /* Either 1 or 2 */ |
| struct rbd_client *rbd_client; |
| |
| char name[DEV_NAME_LEN]; /* blkdev name, e.g. rbd3 */ |
| |
| spinlock_t lock; /* queue, flags, open_count */ |
| |
| struct rbd_image_header header; |
| unsigned long flags; /* possibly lock protected */ |
| struct rbd_spec *spec; |
| struct rbd_options *opts; |
| |
| struct ceph_object_id header_oid; |
| struct ceph_object_locator header_oloc; |
| |
| struct ceph_file_layout layout; |
| |
| struct ceph_osd_linger_request *watch_handle; |
| |
| struct rbd_spec *parent_spec; |
| u64 parent_overlap; |
| atomic_t parent_ref; |
| struct rbd_device *parent; |
| |
| /* Block layer tags. */ |
| struct blk_mq_tag_set tag_set; |
| |
| /* protects updating the header */ |
| struct rw_semaphore header_rwsem; |
| |
| struct rbd_mapping mapping; |
| |
| struct list_head node; |
| |
| /* sysfs related */ |
| struct device dev; |
| unsigned long open_count; /* protected by lock */ |
| }; |
| |
| /* |
| * Flag bits for rbd_dev->flags. If atomicity is required, |
| * rbd_dev->lock is used to protect access. |
| * |
| * Currently, only the "removing" flag (which is coupled with the |
| * "open_count" field) requires atomic access. |
| */ |
| enum rbd_dev_flags { |
| RBD_DEV_FLAG_EXISTS, /* mapped snapshot has not been deleted */ |
| RBD_DEV_FLAG_REMOVING, /* this mapping is being removed */ |
| }; |
| |
| static DEFINE_MUTEX(client_mutex); /* Serialize client creation */ |
| |
| static LIST_HEAD(rbd_dev_list); /* devices */ |
| static DEFINE_SPINLOCK(rbd_dev_list_lock); |
| |
| static LIST_HEAD(rbd_client_list); /* clients */ |
| static DEFINE_SPINLOCK(rbd_client_list_lock); |
| |
| /* Slab caches for frequently-allocated structures */ |
| |
| static struct kmem_cache *rbd_img_request_cache; |
| static struct kmem_cache *rbd_obj_request_cache; |
| static struct kmem_cache *rbd_segment_name_cache; |
| |
| static int rbd_major; |
| static DEFINE_IDA(rbd_dev_id_ida); |
| |
| static struct workqueue_struct *rbd_wq; |
| |
| /* |
| * Default to false for now, as single-major requires >= 0.75 version of |
| * userspace rbd utility. |
| */ |
| static bool single_major = false; |
| module_param(single_major, bool, S_IRUGO); |
| MODULE_PARM_DESC(single_major, "Use a single major number for all rbd devices (default: false)"); |
| |
| static int rbd_img_request_submit(struct rbd_img_request *img_request); |
| |
| static ssize_t rbd_add(struct bus_type *bus, const char *buf, |
| size_t count); |
| static ssize_t rbd_remove(struct bus_type *bus, const char *buf, |
| size_t count); |
| static ssize_t rbd_add_single_major(struct bus_type *bus, const char *buf, |
| size_t count); |
| static ssize_t rbd_remove_single_major(struct bus_type *bus, const char *buf, |
| size_t count); |
| static int rbd_dev_image_probe(struct rbd_device *rbd_dev, int depth); |
| static void rbd_spec_put(struct rbd_spec *spec); |
| |
| static int rbd_dev_id_to_minor(int dev_id) |
| { |
| return dev_id << RBD_SINGLE_MAJOR_PART_SHIFT; |
| } |
| |
| static int minor_to_rbd_dev_id(int minor) |
| { |
| return minor >> RBD_SINGLE_MAJOR_PART_SHIFT; |
| } |
| |
| static BUS_ATTR(add, S_IWUSR, NULL, rbd_add); |
| static BUS_ATTR(remove, S_IWUSR, NULL, rbd_remove); |
| static BUS_ATTR(add_single_major, S_IWUSR, NULL, rbd_add_single_major); |
| static BUS_ATTR(remove_single_major, S_IWUSR, NULL, rbd_remove_single_major); |
| |
| static struct attribute *rbd_bus_attrs[] = { |
| &bus_attr_add.attr, |
| &bus_attr_remove.attr, |
| &bus_attr_add_single_major.attr, |
| &bus_attr_remove_single_major.attr, |
| NULL, |
| }; |
| |
| static umode_t rbd_bus_is_visible(struct kobject *kobj, |
| struct attribute *attr, int index) |
| { |
| if (!single_major && |
| (attr == &bus_attr_add_single_major.attr || |
| attr == &bus_attr_remove_single_major.attr)) |
| return 0; |
| |
| return attr->mode; |
| } |
| |
| static const struct attribute_group rbd_bus_group = { |
| .attrs = rbd_bus_attrs, |
| .is_visible = rbd_bus_is_visible, |
| }; |
| __ATTRIBUTE_GROUPS(rbd_bus); |
| |
| static struct bus_type rbd_bus_type = { |
| .name = "rbd", |
| .bus_groups = rbd_bus_groups, |
| }; |
| |
| static void rbd_root_dev_release(struct device *dev) |
| { |
| } |
| |
| static struct device rbd_root_dev = { |
| .init_name = "rbd", |
| .release = rbd_root_dev_release, |
| }; |
| |
| static __printf(2, 3) |
| void rbd_warn(struct rbd_device *rbd_dev, const char *fmt, ...) |
| { |
| struct va_format vaf; |
| va_list args; |
| |
| va_start(args, fmt); |
| vaf.fmt = fmt; |
| vaf.va = &args; |
| |
| if (!rbd_dev) |
| printk(KERN_WARNING "%s: %pV\n", RBD_DRV_NAME, &vaf); |
| else if (rbd_dev->disk) |
| printk(KERN_WARNING "%s: %s: %pV\n", |
| RBD_DRV_NAME, rbd_dev->disk->disk_name, &vaf); |
| else if (rbd_dev->spec && rbd_dev->spec->image_name) |
| printk(KERN_WARNING "%s: image %s: %pV\n", |
| RBD_DRV_NAME, rbd_dev->spec->image_name, &vaf); |
| else if (rbd_dev->spec && rbd_dev->spec->image_id) |
| printk(KERN_WARNING "%s: id %s: %pV\n", |
| RBD_DRV_NAME, rbd_dev->spec->image_id, &vaf); |
| else /* punt */ |
| printk(KERN_WARNING "%s: rbd_dev %p: %pV\n", |
| RBD_DRV_NAME, rbd_dev, &vaf); |
| va_end(args); |
| } |
| |
| #ifdef RBD_DEBUG |
| #define rbd_assert(expr) \ |
| if (unlikely(!(expr))) { \ |
| printk(KERN_ERR "\nAssertion failure in %s() " \ |
| "at line %d:\n\n" \ |
| "\trbd_assert(%s);\n\n", \ |
| __func__, __LINE__, #expr); \ |
| BUG(); \ |
| } |
| #else /* !RBD_DEBUG */ |
| # define rbd_assert(expr) ((void) 0) |
| #endif /* !RBD_DEBUG */ |
| |
| static void rbd_osd_copyup_callback(struct rbd_obj_request *obj_request); |
| static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request); |
| static void rbd_img_parent_read(struct rbd_obj_request *obj_request); |
| static void rbd_dev_remove_parent(struct rbd_device *rbd_dev); |
| |
| static int rbd_dev_refresh(struct rbd_device *rbd_dev); |
| static int rbd_dev_v2_header_onetime(struct rbd_device *rbd_dev); |
| static int rbd_dev_header_info(struct rbd_device *rbd_dev); |
| static int rbd_dev_v2_parent_info(struct rbd_device *rbd_dev); |
| static const char *rbd_dev_v2_snap_name(struct rbd_device *rbd_dev, |
| u64 snap_id); |
| static int _rbd_dev_v2_snap_size(struct rbd_device *rbd_dev, u64 snap_id, |
| u8 *order, u64 *snap_size); |
| static int _rbd_dev_v2_snap_features(struct rbd_device *rbd_dev, u64 snap_id, |
| u64 *snap_features); |
| |
| static int rbd_open(struct block_device *bdev, fmode_t mode) |
| { |
| struct rbd_device *rbd_dev = bdev->bd_disk->private_data; |
| bool removing = false; |
| |
| if ((mode & FMODE_WRITE) && rbd_dev->mapping.read_only) |
| return -EROFS; |
| |
| spin_lock_irq(&rbd_dev->lock); |
| if (test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags)) |
| removing = true; |
| else |
| rbd_dev->open_count++; |
| spin_unlock_irq(&rbd_dev->lock); |
| if (removing) |
| return -ENOENT; |
| |
| (void) get_device(&rbd_dev->dev); |
| |
| return 0; |
| } |
| |
| static void rbd_release(struct gendisk *disk, fmode_t mode) |
| { |
| struct rbd_device *rbd_dev = disk->private_data; |
| unsigned long open_count_before; |
| |
| spin_lock_irq(&rbd_dev->lock); |
| open_count_before = rbd_dev->open_count--; |
| spin_unlock_irq(&rbd_dev->lock); |
| rbd_assert(open_count_before > 0); |
| |
| put_device(&rbd_dev->dev); |
| } |
| |
| static int rbd_ioctl_set_ro(struct rbd_device *rbd_dev, unsigned long arg) |
| { |
| int ret = 0; |
| int val; |
| bool ro; |
| bool ro_changed = false; |
| |
| /* get_user() may sleep, so call it before taking rbd_dev->lock */ |
| if (get_user(val, (int __user *)(arg))) |
| return -EFAULT; |
| |
| ro = val ? true : false; |
| /* Snapshot doesn't allow to write*/ |
| if (rbd_dev->spec->snap_id != CEPH_NOSNAP && !ro) |
| return -EROFS; |
| |
| spin_lock_irq(&rbd_dev->lock); |
| /* prevent others open this device */ |
| if (rbd_dev->open_count > 1) { |
| ret = -EBUSY; |
| goto out; |
| } |
| |
| if (rbd_dev->mapping.read_only != ro) { |
| rbd_dev->mapping.read_only = ro; |
| ro_changed = true; |
| } |
| |
| out: |
| spin_unlock_irq(&rbd_dev->lock); |
| /* set_disk_ro() may sleep, so call it after releasing rbd_dev->lock */ |
| if (ret == 0 && ro_changed) |
| set_disk_ro(rbd_dev->disk, ro ? 1 : 0); |
| |
| return ret; |
| } |
| |
| static int rbd_ioctl(struct block_device *bdev, fmode_t mode, |
| unsigned int cmd, unsigned long arg) |
| { |
| struct rbd_device *rbd_dev = bdev->bd_disk->private_data; |
| int ret = 0; |
| |
| switch (cmd) { |
| case BLKROSET: |
| ret = rbd_ioctl_set_ro(rbd_dev, arg); |
| break; |
| default: |
| ret = -ENOTTY; |
| } |
| |
| return ret; |
| } |
| |
| #ifdef CONFIG_COMPAT |
| static int rbd_compat_ioctl(struct block_device *bdev, fmode_t mode, |
| unsigned int cmd, unsigned long arg) |
| { |
| return rbd_ioctl(bdev, mode, cmd, arg); |
| } |
| #endif /* CONFIG_COMPAT */ |
| |
| static const struct block_device_operations rbd_bd_ops = { |
| .owner = THIS_MODULE, |
| .open = rbd_open, |
| .release = rbd_release, |
| .ioctl = rbd_ioctl, |
| #ifdef CONFIG_COMPAT |
| .compat_ioctl = rbd_compat_ioctl, |
| #endif |
| }; |
| |
| /* |
| * Initialize an rbd client instance. Success or not, this function |
| * consumes ceph_opts. Caller holds client_mutex. |
| */ |
| static struct rbd_client *rbd_client_create(struct ceph_options *ceph_opts) |
| { |
| struct rbd_client *rbdc; |
| int ret = -ENOMEM; |
| |
| dout("%s:\n", __func__); |
| rbdc = kmalloc(sizeof(struct rbd_client), GFP_KERNEL); |
| if (!rbdc) |
| goto out_opt; |
| |
| kref_init(&rbdc->kref); |
| INIT_LIST_HEAD(&rbdc->node); |
| |
| rbdc->client = ceph_create_client(ceph_opts, rbdc, 0, 0); |
| if (IS_ERR(rbdc->client)) |
| goto out_rbdc; |
| ceph_opts = NULL; /* Now rbdc->client is responsible for ceph_opts */ |
| |
| ret = ceph_open_session(rbdc->client); |
| if (ret < 0) |
| goto out_client; |
| |
| spin_lock(&rbd_client_list_lock); |
| list_add_tail(&rbdc->node, &rbd_client_list); |
| spin_unlock(&rbd_client_list_lock); |
| |
| dout("%s: rbdc %p\n", __func__, rbdc); |
| |
| return rbdc; |
| out_client: |
| ceph_destroy_client(rbdc->client); |
| out_rbdc: |
| kfree(rbdc); |
| out_opt: |
| if (ceph_opts) |
| ceph_destroy_options(ceph_opts); |
| dout("%s: error %d\n", __func__, ret); |
| |
| return ERR_PTR(ret); |
| } |
| |
| static struct rbd_client *__rbd_get_client(struct rbd_client *rbdc) |
| { |
| kref_get(&rbdc->kref); |
| |
| return rbdc; |
| } |
| |
| /* |
| * Find a ceph client with specific addr and configuration. If |
| * found, bump its reference count. |
| */ |
| static struct rbd_client *rbd_client_find(struct ceph_options *ceph_opts) |
| { |
| struct rbd_client *client_node; |
| bool found = false; |
| |
| if (ceph_opts->flags & CEPH_OPT_NOSHARE) |
| return NULL; |
| |
| spin_lock(&rbd_client_list_lock); |
| list_for_each_entry(client_node, &rbd_client_list, node) { |
| if (!ceph_compare_options(ceph_opts, client_node->client)) { |
| __rbd_get_client(client_node); |
| |
| found = true; |
| break; |
| } |
| } |
| spin_unlock(&rbd_client_list_lock); |
| |
| return found ? client_node : NULL; |
| } |
| |
| /* |
| * (Per device) rbd map options |
| */ |
| enum { |
| Opt_queue_depth, |
| Opt_last_int, |
| /* int args above */ |
| Opt_last_string, |
| /* string args above */ |
| Opt_read_only, |
| Opt_read_write, |
| Opt_err |
| }; |
| |
| static match_table_t rbd_opts_tokens = { |
| {Opt_queue_depth, "queue_depth=%d"}, |
| /* int args above */ |
| /* string args above */ |
| {Opt_read_only, "read_only"}, |
| {Opt_read_only, "ro"}, /* Alternate spelling */ |
| {Opt_read_write, "read_write"}, |
| {Opt_read_write, "rw"}, /* Alternate spelling */ |
| {Opt_err, NULL} |
| }; |
| |
| struct rbd_options { |
| int queue_depth; |
| bool read_only; |
| }; |
| |
| #define RBD_QUEUE_DEPTH_DEFAULT BLKDEV_MAX_RQ |
| #define RBD_READ_ONLY_DEFAULT false |
| |
| static int parse_rbd_opts_token(char *c, void *private) |
| { |
| struct rbd_options *rbd_opts = private; |
| substring_t argstr[MAX_OPT_ARGS]; |
| int token, intval, ret; |
| |
| token = match_token(c, rbd_opts_tokens, argstr); |
| if (token < Opt_last_int) { |
| ret = match_int(&argstr[0], &intval); |
| if (ret < 0) { |
| pr_err("bad mount option arg (not int) at '%s'\n", c); |
| return ret; |
| } |
| dout("got int token %d val %d\n", token, intval); |
| } else if (token > Opt_last_int && token < Opt_last_string) { |
| dout("got string token %d val %s\n", token, argstr[0].from); |
| } else { |
| dout("got token %d\n", token); |
| } |
| |
| switch (token) { |
| case Opt_queue_depth: |
| if (intval < 1) { |
| pr_err("queue_depth out of range\n"); |
| return -EINVAL; |
| } |
| rbd_opts->queue_depth = intval; |
| break; |
| case Opt_read_only: |
| rbd_opts->read_only = true; |
| break; |
| case Opt_read_write: |
| rbd_opts->read_only = false; |
| break; |
| default: |
| /* libceph prints "bad option" msg */ |
| return -EINVAL; |
| } |
| |
| return 0; |
| } |
| |
| static char* obj_op_name(enum obj_operation_type op_type) |
| { |
| switch (op_type) { |
| case OBJ_OP_READ: |
| return "read"; |
| case OBJ_OP_WRITE: |
| return "write"; |
| case OBJ_OP_DISCARD: |
| return "discard"; |
| default: |
| return "???"; |
| } |
| } |
| |
| /* |
| * Get a ceph client with specific addr and configuration, if one does |
| * not exist create it. Either way, ceph_opts is consumed by this |
| * function. |
| */ |
| static struct rbd_client *rbd_get_client(struct ceph_options *ceph_opts) |
| { |
| struct rbd_client *rbdc; |
| |
| mutex_lock_nested(&client_mutex, SINGLE_DEPTH_NESTING); |
| rbdc = rbd_client_find(ceph_opts); |
| if (rbdc) /* using an existing client */ |
| ceph_destroy_options(ceph_opts); |
| else |
| rbdc = rbd_client_create(ceph_opts); |
| mutex_unlock(&client_mutex); |
| |
| return rbdc; |
| } |
| |
| /* |
| * Destroy ceph client |
| * |
| * Caller must hold rbd_client_list_lock. |
| */ |
| static void rbd_client_release(struct kref *kref) |
| { |
| struct rbd_client *rbdc = container_of(kref, struct rbd_client, kref); |
| |
| dout("%s: rbdc %p\n", __func__, rbdc); |
| spin_lock(&rbd_client_list_lock); |
| list_del(&rbdc->node); |
| spin_unlock(&rbd_client_list_lock); |
| |
| ceph_destroy_client(rbdc->client); |
| kfree(rbdc); |
| } |
| |
| /* |
| * Drop reference to ceph client node. If it's not referenced anymore, release |
| * it. |
| */ |
| static void rbd_put_client(struct rbd_client *rbdc) |
| { |
| if (rbdc) |
| kref_put(&rbdc->kref, rbd_client_release); |
| } |
| |
| static bool rbd_image_format_valid(u32 image_format) |
| { |
| return image_format == 1 || image_format == 2; |
| } |
| |
| static bool rbd_dev_ondisk_valid(struct rbd_image_header_ondisk *ondisk) |
| { |
| size_t size; |
| u32 snap_count; |
| |
| /* The header has to start with the magic rbd header text */ |
| if (memcmp(&ondisk->text, RBD_HEADER_TEXT, sizeof (RBD_HEADER_TEXT))) |
| return false; |
| |
| /* The bio layer requires at least sector-sized I/O */ |
| |
| if (ondisk->options.order < SECTOR_SHIFT) |
| return false; |
| |
| /* If we use u64 in a few spots we may be able to loosen this */ |
| |
| if (ondisk->options.order > 8 * sizeof (int) - 1) |
| return false; |
| |
| /* |
| * The size of a snapshot header has to fit in a size_t, and |
| * that limits the number of snapshots. |
| */ |
| snap_count = le32_to_cpu(ondisk->snap_count); |
| size = SIZE_MAX - sizeof (struct ceph_snap_context); |
| if (snap_count > size / sizeof (__le64)) |
| return false; |
| |
| /* |
| * Not only that, but the size of the entire the snapshot |
| * header must also be representable in a size_t. |
| */ |
| size -= snap_count * sizeof (__le64); |
| if ((u64) size < le64_to_cpu(ondisk->snap_names_len)) |
| return false; |
| |
| return true; |
| } |
| |
| /* |
| * Fill an rbd image header with information from the given format 1 |
| * on-disk header. |
| */ |
| static int rbd_header_from_disk(struct rbd_device *rbd_dev, |
| struct rbd_image_header_ondisk *ondisk) |
| { |
| struct rbd_image_header *header = &rbd_dev->header; |
| bool first_time = header->object_prefix == NULL; |
| struct ceph_snap_context *snapc; |
| char *object_prefix = NULL; |
| char *snap_names = NULL; |
| u64 *snap_sizes = NULL; |
| u32 snap_count; |
| size_t size; |
| int ret = -ENOMEM; |
| u32 i; |
| |
| /* Allocate this now to avoid having to handle failure below */ |
| |
| if (first_time) { |
| size_t len; |
| |
| len = strnlen(ondisk->object_prefix, |
| sizeof (ondisk->object_prefix)); |
| object_prefix = kmalloc(len + 1, GFP_KERNEL); |
| if (!object_prefix) |
| return -ENOMEM; |
| memcpy(object_prefix, ondisk->object_prefix, len); |
| object_prefix[len] = '\0'; |
| } |
| |
| /* Allocate the snapshot context and fill it in */ |
| |
| snap_count = le32_to_cpu(ondisk->snap_count); |
| snapc = ceph_create_snap_context(snap_count, GFP_KERNEL); |
| if (!snapc) |
| goto out_err; |
| snapc->seq = le64_to_cpu(ondisk->snap_seq); |
| if (snap_count) { |
| struct rbd_image_snap_ondisk *snaps; |
| u64 snap_names_len = le64_to_cpu(ondisk->snap_names_len); |
| |
| /* We'll keep a copy of the snapshot names... */ |
| |
| if (snap_names_len > (u64)SIZE_MAX) |
| goto out_2big; |
| snap_names = kmalloc(snap_names_len, GFP_KERNEL); |
| if (!snap_names) |
| goto out_err; |
| |
| /* ...as well as the array of their sizes. */ |
| |
| size = snap_count * sizeof (*header->snap_sizes); |
| snap_sizes = kmalloc(size, GFP_KERNEL); |
| if (!snap_sizes) |
| goto out_err; |
| |
| /* |
| * Copy the names, and fill in each snapshot's id |
| * and size. |
| * |
| * Note that rbd_dev_v1_header_info() guarantees the |
| * ondisk buffer we're working with has |
| * snap_names_len bytes beyond the end of the |
| * snapshot id array, this memcpy() is safe. |
| */ |
| memcpy(snap_names, &ondisk->snaps[snap_count], snap_names_len); |
| snaps = ondisk->snaps; |
| for (i = 0; i < snap_count; i++) { |
| snapc->snaps[i] = le64_to_cpu(snaps[i].id); |
| snap_sizes[i] = le64_to_cpu(snaps[i].image_size); |
| } |
| } |
| |
| /* We won't fail any more, fill in the header */ |
| |
| if (first_time) { |
| header->object_prefix = object_prefix; |
| header->obj_order = ondisk->options.order; |
| header->crypt_type = ondisk->options.crypt_type; |
| header->comp_type = ondisk->options.comp_type; |
| /* The rest aren't used for format 1 images */ |
| header->stripe_unit = 0; |
| header->stripe_count = 0; |
| header->features = 0; |
| } else { |
| ceph_put_snap_context(header->snapc); |
| kfree(header->snap_names); |
| kfree(header->snap_sizes); |
| } |
| |
| /* The remaining fields always get updated (when we refresh) */ |
| |
| header->image_size = le64_to_cpu(ondisk->image_size); |
| header->snapc = snapc; |
| header->snap_names = snap_names; |
| header->snap_sizes = snap_sizes; |
| |
| return 0; |
| out_2big: |
| ret = -EIO; |
| out_err: |
| kfree(snap_sizes); |
| kfree(snap_names); |
| ceph_put_snap_context(snapc); |
| kfree(object_prefix); |
| |
| return ret; |
| } |
| |
| static const char *_rbd_dev_v1_snap_name(struct rbd_device *rbd_dev, u32 which) |
| { |
| const char *snap_name; |
| |
| rbd_assert(which < rbd_dev->header.snapc->num_snaps); |
| |
| /* Skip over names until we find the one we are looking for */ |
| |
| snap_name = rbd_dev->header.snap_names; |
| while (which--) |
| snap_name += strlen(snap_name) + 1; |
| |
| return kstrdup(snap_name, GFP_KERNEL); |
| } |
| |
| /* |
| * Snapshot id comparison function for use with qsort()/bsearch(). |
| * Note that result is for snapshots in *descending* order. |
| */ |
| static int snapid_compare_reverse(const void *s1, const void *s2) |
| { |
| u64 snap_id1 = *(u64 *)s1; |
| u64 snap_id2 = *(u64 *)s2; |
| |
| if (snap_id1 < snap_id2) |
| return 1; |
| return snap_id1 == snap_id2 ? 0 : -1; |
| } |
| |
| /* |
| * Search a snapshot context to see if the given snapshot id is |
| * present. |
| * |
| * Returns the position of the snapshot id in the array if it's found, |
| * or BAD_SNAP_INDEX otherwise. |
| * |
| * Note: The snapshot array is in kept sorted (by the osd) in |
| * reverse order, highest snapshot id first. |
| */ |
| static u32 rbd_dev_snap_index(struct rbd_device *rbd_dev, u64 snap_id) |
| { |
| struct ceph_snap_context *snapc = rbd_dev->header.snapc; |
| u64 *found; |
| |
| found = bsearch(&snap_id, &snapc->snaps, snapc->num_snaps, |
| sizeof (snap_id), snapid_compare_reverse); |
| |
| return found ? (u32)(found - &snapc->snaps[0]) : BAD_SNAP_INDEX; |
| } |
| |
| static const char *rbd_dev_v1_snap_name(struct rbd_device *rbd_dev, |
| u64 snap_id) |
| { |
| u32 which; |
| const char *snap_name; |
| |
| which = rbd_dev_snap_index(rbd_dev, snap_id); |
| if (which == BAD_SNAP_INDEX) |
| return ERR_PTR(-ENOENT); |
| |
| snap_name = _rbd_dev_v1_snap_name(rbd_dev, which); |
| return snap_name ? snap_name : ERR_PTR(-ENOMEM); |
| } |
| |
| static const char *rbd_snap_name(struct rbd_device *rbd_dev, u64 snap_id) |
| { |
| if (snap_id == CEPH_NOSNAP) |
| return RBD_SNAP_HEAD_NAME; |
| |
| rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); |
| if (rbd_dev->image_format == 1) |
| return rbd_dev_v1_snap_name(rbd_dev, snap_id); |
| |
| return rbd_dev_v2_snap_name(rbd_dev, snap_id); |
| } |
| |
| static int rbd_snap_size(struct rbd_device *rbd_dev, u64 snap_id, |
| u64 *snap_size) |
| { |
| rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); |
| if (snap_id == CEPH_NOSNAP) { |
| *snap_size = rbd_dev->header.image_size; |
| } else if (rbd_dev->image_format == 1) { |
| u32 which; |
| |
| which = rbd_dev_snap_index(rbd_dev, snap_id); |
| if (which == BAD_SNAP_INDEX) |
| return -ENOENT; |
| |
| *snap_size = rbd_dev->header.snap_sizes[which]; |
| } else { |
| u64 size = 0; |
| int ret; |
| |
| ret = _rbd_dev_v2_snap_size(rbd_dev, snap_id, NULL, &size); |
| if (ret) |
| return ret; |
| |
| *snap_size = size; |
| } |
| return 0; |
| } |
| |
| static int rbd_snap_features(struct rbd_device *rbd_dev, u64 snap_id, |
| u64 *snap_features) |
| { |
| rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); |
| if (snap_id == CEPH_NOSNAP) { |
| *snap_features = rbd_dev->header.features; |
| } else if (rbd_dev->image_format == 1) { |
| *snap_features = 0; /* No features for format 1 */ |
| } else { |
| u64 features = 0; |
| int ret; |
| |
| ret = _rbd_dev_v2_snap_features(rbd_dev, snap_id, &features); |
| if (ret) |
| return ret; |
| |
| *snap_features = features; |
| } |
| return 0; |
| } |
| |
| static int rbd_dev_mapping_set(struct rbd_device *rbd_dev) |
| { |
| u64 snap_id = rbd_dev->spec->snap_id; |
| u64 size = 0; |
| u64 features = 0; |
| int ret; |
| |
| ret = rbd_snap_size(rbd_dev, snap_id, &size); |
| if (ret) |
| return ret; |
| ret = rbd_snap_features(rbd_dev, snap_id, &features); |
| if (ret) |
| return ret; |
| |
| rbd_dev->mapping.size = size; |
| rbd_dev->mapping.features = features; |
| |
| return 0; |
| } |
| |
| static void rbd_dev_mapping_clear(struct rbd_device *rbd_dev) |
| { |
| rbd_dev->mapping.size = 0; |
| rbd_dev->mapping.features = 0; |
| } |
| |
| static void rbd_segment_name_free(const char *name) |
| { |
| /* The explicit cast here is needed to drop the const qualifier */ |
| |
| kmem_cache_free(rbd_segment_name_cache, (void *)name); |
| } |
| |
| static const char *rbd_segment_name(struct rbd_device *rbd_dev, u64 offset) |
| { |
| char *name; |
| u64 segment; |
| int ret; |
| char *name_format; |
| |
| name = kmem_cache_alloc(rbd_segment_name_cache, GFP_NOIO); |
| if (!name) |
| return NULL; |
| segment = offset >> rbd_dev->header.obj_order; |
| name_format = "%s.%012llx"; |
| if (rbd_dev->image_format == 2) |
| name_format = "%s.%016llx"; |
| ret = snprintf(name, CEPH_MAX_OID_NAME_LEN + 1, name_format, |
| rbd_dev->header.object_prefix, segment); |
| if (ret < 0 || ret > CEPH_MAX_OID_NAME_LEN) { |
| pr_err("error formatting segment name for #%llu (%d)\n", |
| segment, ret); |
| rbd_segment_name_free(name); |
| name = NULL; |
| } |
| |
| return name; |
| } |
| |
| static u64 rbd_segment_offset(struct rbd_device *rbd_dev, u64 offset) |
| { |
| u64 segment_size = (u64) 1 << rbd_dev->header.obj_order; |
| |
| return offset & (segment_size - 1); |
| } |
| |
| static u64 rbd_segment_length(struct rbd_device *rbd_dev, |
| u64 offset, u64 length) |
| { |
| u64 segment_size = (u64) 1 << rbd_dev->header.obj_order; |
| |
| offset &= segment_size - 1; |
| |
| rbd_assert(length <= U64_MAX - offset); |
| if (offset + length > segment_size) |
| length = segment_size - offset; |
| |
| return length; |
| } |
| |
| /* |
| * returns the size of an object in the image |
| */ |
| static u64 rbd_obj_bytes(struct rbd_image_header *header) |
| { |
| return 1 << header->obj_order; |
| } |
| |
| /* |
| * bio helpers |
| */ |
| |
| static void bio_chain_put(struct bio *chain) |
| { |
| struct bio *tmp; |
| |
| while (chain) { |
| tmp = chain; |
| chain = chain->bi_next; |
| bio_put(tmp); |
| } |
| } |
| |
| /* |
| * zeros a bio chain, starting at specific offset |
| */ |
| static void zero_bio_chain(struct bio *chain, int start_ofs) |
| { |
| struct bio_vec bv; |
| struct bvec_iter iter; |
| unsigned long flags; |
| void *buf; |
| int pos = 0; |
| |
| while (chain) { |
| bio_for_each_segment(bv, chain, iter) { |
| if (pos + bv.bv_len > start_ofs) { |
| int remainder = max(start_ofs - pos, 0); |
| buf = bvec_kmap_irq(&bv, &flags); |
| memset(buf + remainder, 0, |
| bv.bv_len - remainder); |
| flush_dcache_page(bv.bv_page); |
| bvec_kunmap_irq(buf, &flags); |
| } |
| pos += bv.bv_len; |
| } |
| |
| chain = chain->bi_next; |
| } |
| } |
| |
| /* |
| * similar to zero_bio_chain(), zeros data defined by a page array, |
| * starting at the given byte offset from the start of the array and |
| * continuing up to the given end offset. The pages array is |
| * assumed to be big enough to hold all bytes up to the end. |
| */ |
| static void zero_pages(struct page **pages, u64 offset, u64 end) |
| { |
| struct page **page = &pages[offset >> PAGE_SHIFT]; |
| |
| rbd_assert(end > offset); |
| rbd_assert(end - offset <= (u64)SIZE_MAX); |
| while (offset < end) { |
| size_t page_offset; |
| size_t length; |
| unsigned long flags; |
| void *kaddr; |
| |
| page_offset = offset & ~PAGE_MASK; |
| length = min_t(size_t, PAGE_SIZE - page_offset, end - offset); |
| local_irq_save(flags); |
| kaddr = kmap_atomic(*page); |
| memset(kaddr + page_offset, 0, length); |
| flush_dcache_page(*page); |
| kunmap_atomic(kaddr); |
| local_irq_restore(flags); |
| |
| offset += length; |
| page++; |
| } |
| } |
| |
| /* |
| * Clone a portion of a bio, starting at the given byte offset |
| * and continuing for the number of bytes indicated. |
| */ |
| static struct bio *bio_clone_range(struct bio *bio_src, |
| unsigned int offset, |
| unsigned int len, |
| gfp_t gfpmask) |
| { |
| struct bio *bio; |
| |
| bio = bio_clone(bio_src, gfpmask); |
| if (!bio) |
| return NULL; /* ENOMEM */ |
| |
| bio_advance(bio, offset); |
| bio->bi_iter.bi_size = len; |
| |
| return bio; |
| } |
| |
| /* |
| * Clone a portion of a bio chain, starting at the given byte offset |
| * into the first bio in the source chain and continuing for the |
| * number of bytes indicated. The result is another bio chain of |
| * exactly the given length, or a null pointer on error. |
| * |
| * The bio_src and offset parameters are both in-out. On entry they |
| * refer to the first source bio and the offset into that bio where |
| * the start of data to be cloned is located. |
| * |
| * On return, bio_src is updated to refer to the bio in the source |
| * chain that contains first un-cloned byte, and *offset will |
| * contain the offset of that byte within that bio. |
| */ |
| static struct bio *bio_chain_clone_range(struct bio **bio_src, |
| unsigned int *offset, |
| unsigned int len, |
| gfp_t gfpmask) |
| { |
| struct bio *bi = *bio_src; |
| unsigned int off = *offset; |
| struct bio *chain = NULL; |
| struct bio **end; |
| |
| /* Build up a chain of clone bios up to the limit */ |
| |
| if (!bi || off >= bi->bi_iter.bi_size || !len) |
| return NULL; /* Nothing to clone */ |
| |
| end = &chain; |
| while (len) { |
| unsigned int bi_size; |
| struct bio *bio; |
| |
| if (!bi) { |
| rbd_warn(NULL, "bio_chain exhausted with %u left", len); |
| goto out_err; /* EINVAL; ran out of bio's */ |
| } |
| bi_size = min_t(unsigned int, bi->bi_iter.bi_size - off, len); |
| bio = bio_clone_range(bi, off, bi_size, gfpmask); |
| if (!bio) |
| goto out_err; /* ENOMEM */ |
| |
| *end = bio; |
| end = &bio->bi_next; |
| |
| off += bi_size; |
| if (off == bi->bi_iter.bi_size) { |
| bi = bi->bi_next; |
| off = 0; |
| } |
| len -= bi_size; |
| } |
| *bio_src = bi; |
| *offset = off; |
| |
| return chain; |
| out_err: |
| bio_chain_put(chain); |
| |
| return NULL; |
| } |
| |
| /* |
| * The default/initial value for all object request flags is 0. For |
| * each flag, once its value is set to 1 it is never reset to 0 |
| * again. |
| */ |
| static void obj_request_img_data_set(struct rbd_obj_request *obj_request) |
| { |
| if (test_and_set_bit(OBJ_REQ_IMG_DATA, &obj_request->flags)) { |
| struct rbd_device *rbd_dev; |
| |
| rbd_dev = obj_request->img_request->rbd_dev; |
| rbd_warn(rbd_dev, "obj_request %p already marked img_data", |
| obj_request); |
| } |
| } |
| |
| static bool obj_request_img_data_test(struct rbd_obj_request *obj_request) |
| { |
| smp_mb(); |
| return test_bit(OBJ_REQ_IMG_DATA, &obj_request->flags) != 0; |
| } |
| |
| static void obj_request_done_set(struct rbd_obj_request *obj_request) |
| { |
| if (test_and_set_bit(OBJ_REQ_DONE, &obj_request->flags)) { |
| struct rbd_device *rbd_dev = NULL; |
| |
| if (obj_request_img_data_test(obj_request)) |
| rbd_dev = obj_request->img_request->rbd_dev; |
| rbd_warn(rbd_dev, "obj_request %p already marked done", |
| obj_request); |
| } |
| } |
| |
| static bool obj_request_done_test(struct rbd_obj_request *obj_request) |
| { |
| smp_mb(); |
| return test_bit(OBJ_REQ_DONE, &obj_request->flags) != 0; |
| } |
| |
| /* |
| * This sets the KNOWN flag after (possibly) setting the EXISTS |
| * flag. The latter is set based on the "exists" value provided. |
| * |
| * Note that for our purposes once an object exists it never goes |
| * away again. It's possible that the response from two existence |
| * checks are separated by the creation of the target object, and |
| * the first ("doesn't exist") response arrives *after* the second |
| * ("does exist"). In that case we ignore the second one. |
| */ |
| static void obj_request_existence_set(struct rbd_obj_request *obj_request, |
| bool exists) |
| { |
| if (exists) |
| set_bit(OBJ_REQ_EXISTS, &obj_request->flags); |
| set_bit(OBJ_REQ_KNOWN, &obj_request->flags); |
| smp_mb(); |
| } |
| |
| static bool obj_request_known_test(struct rbd_obj_request *obj_request) |
| { |
| smp_mb(); |
| return test_bit(OBJ_REQ_KNOWN, &obj_request->flags) != 0; |
| } |
| |
| static bool obj_request_exists_test(struct rbd_obj_request *obj_request) |
| { |
| smp_mb(); |
| return test_bit(OBJ_REQ_EXISTS, &obj_request->flags) != 0; |
| } |
| |
| static bool obj_request_overlaps_parent(struct rbd_obj_request *obj_request) |
| { |
| struct rbd_device *rbd_dev = obj_request->img_request->rbd_dev; |
| |
| return obj_request->img_offset < |
| round_up(rbd_dev->parent_overlap, rbd_obj_bytes(&rbd_dev->header)); |
| } |
| |
| static void rbd_obj_request_get(struct rbd_obj_request *obj_request) |
| { |
| dout("%s: obj %p (was %d)\n", __func__, obj_request, |
| atomic_read(&obj_request->kref.refcount)); |
| kref_get(&obj_request->kref); |
| } |
| |
| static void rbd_obj_request_destroy(struct kref *kref); |
| static void rbd_obj_request_put(struct rbd_obj_request *obj_request) |
| { |
| rbd_assert(obj_request != NULL); |
| dout("%s: obj %p (was %d)\n", __func__, obj_request, |
| atomic_read(&obj_request->kref.refcount)); |
| kref_put(&obj_request->kref, rbd_obj_request_destroy); |
| } |
| |
| static void rbd_img_request_get(struct rbd_img_request *img_request) |
| { |
| dout("%s: img %p (was %d)\n", __func__, img_request, |
| atomic_read(&img_request->kref.refcount)); |
| kref_get(&img_request->kref); |
| } |
| |
| static bool img_request_child_test(struct rbd_img_request *img_request); |
| static void rbd_parent_request_destroy(struct kref *kref); |
| static void rbd_img_request_destroy(struct kref *kref); |
| static void rbd_img_request_put(struct rbd_img_request *img_request) |
| { |
| rbd_assert(img_request != NULL); |
| dout("%s: img %p (was %d)\n", __func__, img_request, |
| atomic_read(&img_request->kref.refcount)); |
| if (img_request_child_test(img_request)) |
| kref_put(&img_request->kref, rbd_parent_request_destroy); |
| else |
| kref_put(&img_request->kref, rbd_img_request_destroy); |
| } |
| |
| static inline void rbd_img_obj_request_add(struct rbd_img_request *img_request, |
| struct rbd_obj_request *obj_request) |
| { |
| rbd_assert(obj_request->img_request == NULL); |
| |
| /* Image request now owns object's original reference */ |
| obj_request->img_request = img_request; |
| obj_request->which = img_request->obj_request_count; |
| rbd_assert(!obj_request_img_data_test(obj_request)); |
| obj_request_img_data_set(obj_request); |
| rbd_assert(obj_request->which != BAD_WHICH); |
| img_request->obj_request_count++; |
| list_add_tail(&obj_request->links, &img_request->obj_requests); |
| dout("%s: img %p obj %p w=%u\n", __func__, img_request, obj_request, |
| obj_request->which); |
| } |
| |
| static inline void rbd_img_obj_request_del(struct rbd_img_request *img_request, |
| struct rbd_obj_request *obj_request) |
| { |
| rbd_assert(obj_request->which != BAD_WHICH); |
| |
| dout("%s: img %p obj %p w=%u\n", __func__, img_request, obj_request, |
| obj_request->which); |
| list_del(&obj_request->links); |
| rbd_assert(img_request->obj_request_count > 0); |
| img_request->obj_request_count--; |
| rbd_assert(obj_request->which == img_request->obj_request_count); |
| obj_request->which = BAD_WHICH; |
| rbd_assert(obj_request_img_data_test(obj_request)); |
| rbd_assert(obj_request->img_request == img_request); |
| obj_request->img_request = NULL; |
| obj_request->callback = NULL; |
| rbd_obj_request_put(obj_request); |
| } |
| |
| static bool obj_request_type_valid(enum obj_request_type type) |
| { |
| switch (type) { |
| case OBJ_REQUEST_NODATA: |
| case OBJ_REQUEST_BIO: |
| case OBJ_REQUEST_PAGES: |
| return true; |
| default: |
| return false; |
| } |
| } |
| |
| static int rbd_obj_request_submit(struct ceph_osd_client *osdc, |
| struct rbd_obj_request *obj_request) |
| { |
| dout("%s %p\n", __func__, obj_request); |
| return ceph_osdc_start_request(osdc, obj_request->osd_req, false); |
| } |
| |
| static void rbd_obj_request_end(struct rbd_obj_request *obj_request) |
| { |
| dout("%s %p\n", __func__, obj_request); |
| ceph_osdc_cancel_request(obj_request->osd_req); |
| } |
| |
| /* |
| * Wait for an object request to complete. If interrupted, cancel the |
| * underlying osd request. |
| * |
| * @timeout: in jiffies, 0 means "wait forever" |
| */ |
| static int __rbd_obj_request_wait(struct rbd_obj_request *obj_request, |
| unsigned long timeout) |
| { |
| long ret; |
| |
| dout("%s %p\n", __func__, obj_request); |
| ret = wait_for_completion_interruptible_timeout( |
| &obj_request->completion, |
| ceph_timeout_jiffies(timeout)); |
| if (ret <= 0) { |
| if (ret == 0) |
| ret = -ETIMEDOUT; |
| rbd_obj_request_end(obj_request); |
| } else { |
| ret = 0; |
| } |
| |
| dout("%s %p ret %d\n", __func__, obj_request, (int)ret); |
| return ret; |
| } |
| |
| static int rbd_obj_request_wait(struct rbd_obj_request *obj_request) |
| { |
| return __rbd_obj_request_wait(obj_request, 0); |
| } |
| |
| static void rbd_img_request_complete(struct rbd_img_request *img_request) |
| { |
| |
| dout("%s: img %p\n", __func__, img_request); |
| |
| /* |
| * If no error occurred, compute the aggregate transfer |
| * count for the image request. We could instead use |
| * atomic64_cmpxchg() to update it as each object request |
| * completes; not clear which way is better off hand. |
| */ |
| if (!img_request->result) { |
| struct rbd_obj_request *obj_request; |
| u64 xferred = 0; |
| |
| for_each_obj_request(img_request, obj_request) |
| xferred += obj_request->xferred; |
| img_request->xferred = xferred; |
| } |
| |
| if (img_request->callback) |
| img_request->callback(img_request); |
| else |
| rbd_img_request_put(img_request); |
| } |
| |
| /* |
| * The default/initial value for all image request flags is 0. Each |
| * is conditionally set to 1 at image request initialization time |
| * and currently never change thereafter. |
| */ |
| static void img_request_write_set(struct rbd_img_request *img_request) |
| { |
| set_bit(IMG_REQ_WRITE, &img_request->flags); |
| smp_mb(); |
| } |
| |
| static bool img_request_write_test(struct rbd_img_request *img_request) |
| { |
| smp_mb(); |
| return test_bit(IMG_REQ_WRITE, &img_request->flags) != 0; |
| } |
| |
| /* |
| * Set the discard flag when the img_request is an discard request |
| */ |
| static void img_request_discard_set(struct rbd_img_request *img_request) |
| { |
| set_bit(IMG_REQ_DISCARD, &img_request->flags); |
| smp_mb(); |
| } |
| |
| static bool img_request_discard_test(struct rbd_img_request *img_request) |
| { |
| smp_mb(); |
| return test_bit(IMG_REQ_DISCARD, &img_request->flags) != 0; |
| } |
| |
| static void img_request_child_set(struct rbd_img_request *img_request) |
| { |
| set_bit(IMG_REQ_CHILD, &img_request->flags); |
| smp_mb(); |
| } |
| |
| static void img_request_child_clear(struct rbd_img_request *img_request) |
| { |
| clear_bit(IMG_REQ_CHILD, &img_request->flags); |
| smp_mb(); |
| } |
| |
| static bool img_request_child_test(struct rbd_img_request *img_request) |
| { |
| smp_mb(); |
| return test_bit(IMG_REQ_CHILD, &img_request->flags) != 0; |
| } |
| |
| static void img_request_layered_set(struct rbd_img_request *img_request) |
| { |
| set_bit(IMG_REQ_LAYERED, &img_request->flags); |
| smp_mb(); |
| } |
| |
| static void img_request_layered_clear(struct rbd_img_request *img_request) |
| { |
| clear_bit(IMG_REQ_LAYERED, &img_request->flags); |
| smp_mb(); |
| } |
| |
| static bool img_request_layered_test(struct rbd_img_request *img_request) |
| { |
| smp_mb(); |
| return test_bit(IMG_REQ_LAYERED, &img_request->flags) != 0; |
| } |
| |
| static enum obj_operation_type |
| rbd_img_request_op_type(struct rbd_img_request *img_request) |
| { |
| if (img_request_write_test(img_request)) |
| return OBJ_OP_WRITE; |
| else if (img_request_discard_test(img_request)) |
| return OBJ_OP_DISCARD; |
| else |
| return OBJ_OP_READ; |
| } |
| |
| static void |
| rbd_img_obj_request_read_callback(struct rbd_obj_request *obj_request) |
| { |
| u64 xferred = obj_request->xferred; |
| u64 length = obj_request->length; |
| |
| dout("%s: obj %p img %p result %d %llu/%llu\n", __func__, |
| obj_request, obj_request->img_request, obj_request->result, |
| xferred, length); |
| /* |
| * ENOENT means a hole in the image. We zero-fill the entire |
| * length of the request. A short read also implies zero-fill |
| * to the end of the request. An error requires the whole |
| * length of the request to be reported finished with an error |
| * to the block layer. In each case we update the xferred |
| * count to indicate the whole request was satisfied. |
| */ |
| rbd_assert(obj_request->type != OBJ_REQUEST_NODATA); |
| if (obj_request->result == -ENOENT) { |
| if (obj_request->type == OBJ_REQUEST_BIO) |
| zero_bio_chain(obj_request->bio_list, 0); |
| else |
| zero_pages(obj_request->pages, 0, length); |
| obj_request->result = 0; |
| } else if (xferred < length && !obj_request->result) { |
| if (obj_request->type == OBJ_REQUEST_BIO) |
| zero_bio_chain(obj_request->bio_list, xferred); |
| else |
| zero_pages(obj_request->pages, xferred, length); |
| } |
| obj_request->xferred = length; |
| obj_request_done_set(obj_request); |
| } |
| |
| static void rbd_obj_request_complete(struct rbd_obj_request *obj_request) |
| { |
| dout("%s: obj %p cb %p\n", __func__, obj_request, |
| obj_request->callback); |
| if (obj_request->callback) |
| obj_request->callback(obj_request); |
| else |
| complete_all(&obj_request->completion); |
| } |
| |
| static void rbd_osd_read_callback(struct rbd_obj_request *obj_request) |
| { |
| struct rbd_img_request *img_request = NULL; |
| struct rbd_device *rbd_dev = NULL; |
| bool layered = false; |
| |
| if (obj_request_img_data_test(obj_request)) { |
| img_request = obj_request->img_request; |
| layered = img_request && img_request_layered_test(img_request); |
| rbd_dev = img_request->rbd_dev; |
| } |
| |
| dout("%s: obj %p img %p result %d %llu/%llu\n", __func__, |
| obj_request, img_request, obj_request->result, |
| obj_request->xferred, obj_request->length); |
| if (layered && obj_request->result == -ENOENT && |
| obj_request->img_offset < rbd_dev->parent_overlap) |
| rbd_img_parent_read(obj_request); |
| else if (img_request) |
| rbd_img_obj_request_read_callback(obj_request); |
| else |
| obj_request_done_set(obj_request); |
| } |
| |
| static void rbd_osd_write_callback(struct rbd_obj_request *obj_request) |
| { |
| dout("%s: obj %p result %d %llu\n", __func__, obj_request, |
| obj_request->result, obj_request->length); |
| /* |
| * There is no such thing as a successful short write. Set |
| * it to our originally-requested length. |
| */ |
| obj_request->xferred = obj_request->length; |
| obj_request_done_set(obj_request); |
| } |
| |
| static void rbd_osd_discard_callback(struct rbd_obj_request *obj_request) |
| { |
| dout("%s: obj %p result %d %llu\n", __func__, obj_request, |
| obj_request->result, obj_request->length); |
| /* |
| * There is no such thing as a successful short discard. Set |
| * it to our originally-requested length. |
| */ |
| obj_request->xferred = obj_request->length; |
| /* discarding a non-existent object is not a problem */ |
| if (obj_request->result == -ENOENT) |
| obj_request->result = 0; |
| obj_request_done_set(obj_request); |
| } |
| |
| /* |
| * For a simple stat call there's nothing to do. We'll do more if |
| * this is part of a write sequence for a layered image. |
| */ |
| static void rbd_osd_stat_callback(struct rbd_obj_request *obj_request) |
| { |
| dout("%s: obj %p\n", __func__, obj_request); |
| obj_request_done_set(obj_request); |
| } |
| |
| static void rbd_osd_call_callback(struct rbd_obj_request *obj_request) |
| { |
| dout("%s: obj %p\n", __func__, obj_request); |
| |
| if (obj_request_img_data_test(obj_request)) |
| rbd_osd_copyup_callback(obj_request); |
| else |
| obj_request_done_set(obj_request); |
| } |
| |
| static void rbd_osd_req_callback(struct ceph_osd_request *osd_req) |
| { |
| struct rbd_obj_request *obj_request = osd_req->r_priv; |
| u16 opcode; |
| |
| dout("%s: osd_req %p\n", __func__, osd_req); |
| rbd_assert(osd_req == obj_request->osd_req); |
| if (obj_request_img_data_test(obj_request)) { |
| rbd_assert(obj_request->img_request); |
| rbd_assert(obj_request->which != BAD_WHICH); |
| } else { |
| rbd_assert(obj_request->which == BAD_WHICH); |
| } |
| |
| if (osd_req->r_result < 0) |
| obj_request->result = osd_req->r_result; |
| |
| /* |
| * We support a 64-bit length, but ultimately it has to be |
| * passed to the block layer, which just supports a 32-bit |
| * length field. |
| */ |
| obj_request->xferred = osd_req->r_ops[0].outdata_len; |
| rbd_assert(obj_request->xferred < (u64)UINT_MAX); |
| |
| opcode = osd_req->r_ops[0].op; |
| switch (opcode) { |
| case CEPH_OSD_OP_READ: |
| rbd_osd_read_callback(obj_request); |
| break; |
| case CEPH_OSD_OP_SETALLOCHINT: |
| rbd_assert(osd_req->r_ops[1].op == CEPH_OSD_OP_WRITE || |
| osd_req->r_ops[1].op == CEPH_OSD_OP_WRITEFULL); |
| /* fall through */ |
| case CEPH_OSD_OP_WRITE: |
| case CEPH_OSD_OP_WRITEFULL: |
| rbd_osd_write_callback(obj_request); |
| break; |
| case CEPH_OSD_OP_STAT: |
| rbd_osd_stat_callback(obj_request); |
| break; |
| case CEPH_OSD_OP_DELETE: |
| case CEPH_OSD_OP_TRUNCATE: |
| case CEPH_OSD_OP_ZERO: |
| rbd_osd_discard_callback(obj_request); |
| break; |
| case CEPH_OSD_OP_CALL: |
| rbd_osd_call_callback(obj_request); |
| break; |
| default: |
| rbd_warn(NULL, "%s: unsupported op %hu", |
| obj_request->object_name, (unsigned short) opcode); |
| break; |
| } |
| |
| if (obj_request_done_test(obj_request)) |
| rbd_obj_request_complete(obj_request); |
| } |
| |
| static void rbd_osd_req_format_read(struct rbd_obj_request *obj_request) |
| { |
| struct rbd_img_request *img_request = obj_request->img_request; |
| struct ceph_osd_request *osd_req = obj_request->osd_req; |
| |
| if (img_request) |
| osd_req->r_snapid = img_request->snap_id; |
| } |
| |
| static void rbd_osd_req_format_write(struct rbd_obj_request *obj_request) |
| { |
| struct ceph_osd_request *osd_req = obj_request->osd_req; |
| |
| osd_req->r_mtime = CURRENT_TIME; |
| osd_req->r_data_offset = obj_request->offset; |
| } |
| |
| /* |
| * Create an osd request. A read request has one osd op (read). |
| * A write request has either one (watch) or two (hint+write) osd ops. |
| * (All rbd data writes are prefixed with an allocation hint op, but |
| * technically osd watch is a write request, hence this distinction.) |
| */ |
| static struct ceph_osd_request *rbd_osd_req_create( |
| struct rbd_device *rbd_dev, |
| enum obj_operation_type op_type, |
| unsigned int num_ops, |
| struct rbd_obj_request *obj_request) |
| { |
| struct ceph_snap_context *snapc = NULL; |
| struct ceph_osd_client *osdc; |
| struct ceph_osd_request *osd_req; |
| |
| if (obj_request_img_data_test(obj_request) && |
| (op_type == OBJ_OP_DISCARD || op_type == OBJ_OP_WRITE)) { |
| struct rbd_img_request *img_request = obj_request->img_request; |
| if (op_type == OBJ_OP_WRITE) { |
| rbd_assert(img_request_write_test(img_request)); |
| } else { |
| rbd_assert(img_request_discard_test(img_request)); |
| } |
| snapc = img_request->snapc; |
| } |
| |
| rbd_assert(num_ops == 1 || ((op_type == OBJ_OP_WRITE) && num_ops == 2)); |
| |
| /* Allocate and initialize the request, for the num_ops ops */ |
| |
| osdc = &rbd_dev->rbd_client->client->osdc; |
| osd_req = ceph_osdc_alloc_request(osdc, snapc, num_ops, false, |
| GFP_NOIO); |
| if (!osd_req) |
| goto fail; |
| |
| if (op_type == OBJ_OP_WRITE || op_type == OBJ_OP_DISCARD) |
| osd_req->r_flags = CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK; |
| else |
| osd_req->r_flags = CEPH_OSD_FLAG_READ; |
| |
| osd_req->r_callback = rbd_osd_req_callback; |
| osd_req->r_priv = obj_request; |
| |
| osd_req->r_base_oloc.pool = ceph_file_layout_pg_pool(rbd_dev->layout); |
| if (ceph_oid_aprintf(&osd_req->r_base_oid, GFP_NOIO, "%s", |
| obj_request->object_name)) |
| goto fail; |
| |
| if (ceph_osdc_alloc_messages(osd_req, GFP_NOIO)) |
| goto fail; |
| |
| return osd_req; |
| |
| fail: |
| ceph_osdc_put_request(osd_req); |
| return NULL; |
| } |
| |
| /* |
| * Create a copyup osd request based on the information in the object |
| * request supplied. A copyup request has two or three osd ops, a |
| * copyup method call, potentially a hint op, and a write or truncate |
| * or zero op. |
| */ |
| static struct ceph_osd_request * |
| rbd_osd_req_create_copyup(struct rbd_obj_request *obj_request) |
| { |
| struct rbd_img_request *img_request; |
| struct ceph_snap_context *snapc; |
| struct rbd_device *rbd_dev; |
| struct ceph_osd_client *osdc; |
| struct ceph_osd_request *osd_req; |
| int num_osd_ops = 3; |
| |
| rbd_assert(obj_request_img_data_test(obj_request)); |
| img_request = obj_request->img_request; |
| rbd_assert(img_request); |
| rbd_assert(img_request_write_test(img_request) || |
| img_request_discard_test(img_request)); |
| |
| if (img_request_discard_test(img_request)) |
| num_osd_ops = 2; |
| |
| /* Allocate and initialize the request, for all the ops */ |
| |
| snapc = img_request->snapc; |
| rbd_dev = img_request->rbd_dev; |
| osdc = &rbd_dev->rbd_client->client->osdc; |
| osd_req = ceph_osdc_alloc_request(osdc, snapc, num_osd_ops, |
| false, GFP_NOIO); |
| if (!osd_req) |
| goto fail; |
| |
| osd_req->r_flags = CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK; |
| osd_req->r_callback = rbd_osd_req_callback; |
| osd_req->r_priv = obj_request; |
| |
| osd_req->r_base_oloc.pool = ceph_file_layout_pg_pool(rbd_dev->layout); |
| if (ceph_oid_aprintf(&osd_req->r_base_oid, GFP_NOIO, "%s", |
| obj_request->object_name)) |
| goto fail; |
| |
| if (ceph_osdc_alloc_messages(osd_req, GFP_NOIO)) |
| goto fail; |
| |
| return osd_req; |
| |
| fail: |
| ceph_osdc_put_request(osd_req); |
| return NULL; |
| } |
| |
| |
| static void rbd_osd_req_destroy(struct ceph_osd_request *osd_req) |
| { |
| ceph_osdc_put_request(osd_req); |
| } |
| |
| /* object_name is assumed to be a non-null pointer and NUL-terminated */ |
| |
| static struct rbd_obj_request *rbd_obj_request_create(const char *object_name, |
| u64 offset, u64 length, |
| enum obj_request_type type) |
| { |
| struct rbd_obj_request *obj_request; |
| size_t size; |
| char *name; |
| |
| rbd_assert(obj_request_type_valid(type)); |
| |
| size = strlen(object_name) + 1; |
| name = kmalloc(size, GFP_NOIO); |
| if (!name) |
| return NULL; |
| |
| obj_request = kmem_cache_zalloc(rbd_obj_request_cache, GFP_NOIO); |
| if (!obj_request) { |
| kfree(name); |
| return NULL; |
| } |
| |
| obj_request->object_name = memcpy(name, object_name, size); |
| obj_request->offset = offset; |
| obj_request->length = length; |
| obj_request->flags = 0; |
| obj_request->which = BAD_WHICH; |
| obj_request->type = type; |
| INIT_LIST_HEAD(&obj_request->links); |
| init_completion(&obj_request->completion); |
| kref_init(&obj_request->kref); |
| |
| dout("%s: \"%s\" %llu/%llu %d -> obj %p\n", __func__, object_name, |
| offset, length, (int)type, obj_request); |
| |
| return obj_request; |
| } |
| |
| static void rbd_obj_request_destroy(struct kref *kref) |
| { |
| struct rbd_obj_request *obj_request; |
| |
| obj_request = container_of(kref, struct rbd_obj_request, kref); |
| |
| dout("%s: obj %p\n", __func__, obj_request); |
| |
| rbd_assert(obj_request->img_request == NULL); |
| rbd_assert(obj_request->which == BAD_WHICH); |
| |
| if (obj_request->osd_req) |
| rbd_osd_req_destroy(obj_request->osd_req); |
| |
| rbd_assert(obj_request_type_valid(obj_request->type)); |
| switch (obj_request->type) { |
| case OBJ_REQUEST_NODATA: |
| break; /* Nothing to do */ |
| case OBJ_REQUEST_BIO: |
| if (obj_request->bio_list) |
| bio_chain_put(obj_request->bio_list); |
| break; |
| case OBJ_REQUEST_PAGES: |
| if (obj_request->pages) |
| ceph_release_page_vector(obj_request->pages, |
| obj_request->page_count); |
| break; |
| } |
| |
| kfree(obj_request->object_name); |
| obj_request->object_name = NULL; |
| kmem_cache_free(rbd_obj_request_cache, obj_request); |
| } |
| |
| /* It's OK to call this for a device with no parent */ |
| |
| static void rbd_spec_put(struct rbd_spec *spec); |
| static void rbd_dev_unparent(struct rbd_device *rbd_dev) |
| { |
| rbd_dev_remove_parent(rbd_dev); |
| rbd_spec_put(rbd_dev->parent_spec); |
| rbd_dev->parent_spec = NULL; |
| rbd_dev->parent_overlap = 0; |
| } |
| |
| /* |
| * Parent image reference counting is used to determine when an |
| * image's parent fields can be safely torn down--after there are no |
| * more in-flight requests to the parent image. When the last |
| * reference is dropped, cleaning them up is safe. |
| */ |
| static void rbd_dev_parent_put(struct rbd_device *rbd_dev) |
| { |
| int counter; |
| |
| if (!rbd_dev->parent_spec) |
| return; |
| |
| counter = atomic_dec_return_safe(&rbd_dev->parent_ref); |
| if (counter > 0) |
| return; |
| |
| /* Last reference; clean up parent data structures */ |
| |
| if (!counter) |
| rbd_dev_unparent(rbd_dev); |
| else |
| rbd_warn(rbd_dev, "parent reference underflow"); |
| } |
| |
| /* |
| * If an image has a non-zero parent overlap, get a reference to its |
| * parent. |
| * |
| * Returns true if the rbd device has a parent with a non-zero |
| * overlap and a reference for it was successfully taken, or |
| * false otherwise. |
| */ |
| static bool rbd_dev_parent_get(struct rbd_device *rbd_dev) |
| { |
| int counter = 0; |
| |
| if (!rbd_dev->parent_spec) |
| return false; |
| |
| down_read(&rbd_dev->header_rwsem); |
| if (rbd_dev->parent_overlap) |
| counter = atomic_inc_return_safe(&rbd_dev->parent_ref); |
| up_read(&rbd_dev->header_rwsem); |
| |
| if (counter < 0) |
| rbd_warn(rbd_dev, "parent reference overflow"); |
| |
| return counter > 0; |
| } |
| |
| /* |
| * Caller is responsible for filling in the list of object requests |
| * that comprises the image request, and the Linux request pointer |
| * (if there is one). |
| */ |
| static struct rbd_img_request *rbd_img_request_create( |
| struct rbd_device *rbd_dev, |
| u64 offset, u64 length, |
| enum obj_operation_type op_type, |
| struct ceph_snap_context *snapc) |
| { |
| struct rbd_img_request *img_request; |
| |
| img_request = kmem_cache_alloc(rbd_img_request_cache, GFP_NOIO); |
| if (!img_request) |
| return NULL; |
| |
| img_request->rq = NULL; |
| img_request->rbd_dev = rbd_dev; |
| img_request->offset = offset; |
| img_request->length = length; |
| img_request->flags = 0; |
| if (op_type == OBJ_OP_DISCARD) { |
| img_request_discard_set(img_request); |
| img_request->snapc = snapc; |
| } else if (op_type == OBJ_OP_WRITE) { |
| img_request_write_set(img_request); |
| img_request->snapc = snapc; |
| } else { |
| img_request->snap_id = rbd_dev->spec->snap_id; |
| } |
| if (rbd_dev_parent_get(rbd_dev)) |
| img_request_layered_set(img_request); |
| spin_lock_init(&img_request->completion_lock); |
| img_request->next_completion = 0; |
| img_request->callback = NULL; |
| img_request->result = 0; |
| img_request->obj_request_count = 0; |
| INIT_LIST_HEAD(&img_request->obj_requests); |
| kref_init(&img_request->kref); |
| |
| dout("%s: rbd_dev %p %s %llu/%llu -> img %p\n", __func__, rbd_dev, |
| obj_op_name(op_type), offset, length, img_request); |
| |
| return img_request; |
| } |
| |
| static void rbd_img_request_destroy(struct kref *kref) |
| { |
| struct rbd_img_request *img_request; |
| struct rbd_obj_request *obj_request; |
| struct rbd_obj_request *next_obj_request; |
| |
| img_request = container_of(kref, struct rbd_img_request, kref); |
| |
| dout("%s: img %p\n", __func__, img_request); |
| |
| for_each_obj_request_safe(img_request, obj_request, next_obj_request) |
| rbd_img_obj_request_del(img_request, obj_request); |
| rbd_assert(img_request->obj_request_count == 0); |
| |
| if (img_request_layered_test(img_request)) { |
| img_request_layered_clear(img_request); |
| rbd_dev_parent_put(img_request->rbd_dev); |
| } |
| |
| if (img_request_write_test(img_request) || |
| img_request_discard_test(img_request)) |
| ceph_put_snap_context(img_request->snapc); |
| |
| kmem_cache_free(rbd_img_request_cache, img_request); |
| } |
| |
| static struct rbd_img_request *rbd_parent_request_create( |
| struct rbd_obj_request *obj_request, |
| u64 img_offset, u64 length) |
| { |
| struct rbd_img_request *parent_request; |
| struct rbd_device *rbd_dev; |
| |
| rbd_assert(obj_request->img_request); |
| rbd_dev = obj_request->img_request->rbd_dev; |
| |
| parent_request = rbd_img_request_create(rbd_dev->parent, img_offset, |
| length, OBJ_OP_READ, NULL); |
| if (!parent_request) |
| return NULL; |
| |
| img_request_child_set(parent_request); |
| rbd_obj_request_get(obj_request); |
| parent_request->obj_request = obj_request; |
| |
| return parent_request; |
| } |
| |
| static void rbd_parent_request_destroy(struct kref *kref) |
| { |
| struct rbd_img_request *parent_request; |
| struct rbd_obj_request *orig_request; |
| |
| parent_request = container_of(kref, struct rbd_img_request, kref); |
| orig_request = parent_request->obj_request; |
| |
| parent_request->obj_request = NULL; |
| rbd_obj_request_put(orig_request); |
| img_request_child_clear(parent_request); |
| |
| rbd_img_request_destroy(kref); |
| } |
| |
| static bool rbd_img_obj_end_request(struct rbd_obj_request *obj_request) |
| { |
| struct rbd_img_request *img_request; |
| unsigned int xferred; |
| int result; |
| bool more; |
| |
| rbd_assert(obj_request_img_data_test(obj_request)); |
| img_request = obj_request->img_request; |
| |
| rbd_assert(obj_request->xferred <= (u64)UINT_MAX); |
| xferred = (unsigned int)obj_request->xferred; |
| result = obj_request->result; |
| if (result) { |
| struct rbd_device *rbd_dev = img_request->rbd_dev; |
| enum obj_operation_type op_type; |
| |
| if (img_request_discard_test(img_request)) |
| op_type = OBJ_OP_DISCARD; |
| else if (img_request_write_test(img_request)) |
| op_type = OBJ_OP_WRITE; |
| else |
| op_type = OBJ_OP_READ; |
| |
| rbd_warn(rbd_dev, "%s %llx at %llx (%llx)", |
| obj_op_name(op_type), obj_request->length, |
| obj_request->img_offset, obj_request->offset); |
| rbd_warn(rbd_dev, " result %d xferred %x", |
| result, xferred); |
| if (!img_request->result) |
| img_request->result = result; |
| /* |
| * Need to end I/O on the entire obj_request worth of |
| * bytes in case of error. |
| */ |
| xferred = obj_request->length; |
| } |
| |
| /* Image object requests don't own their page array */ |
| |
| if (obj_request->type == OBJ_REQUEST_PAGES) { |
| obj_request->pages = NULL; |
| obj_request->page_count = 0; |
| } |
| |
| if (img_request_child_test(img_request)) { |
| rbd_assert(img_request->obj_request != NULL); |
| more = obj_request->which < img_request->obj_request_count - 1; |
| } else { |
| rbd_assert(img_request->rq != NULL); |
| |
| more = blk_update_request(img_request->rq, result, xferred); |
| if (!more) |
| __blk_mq_end_request(img_request->rq, result); |
| } |
| |
| return more; |
| } |
| |
| static void rbd_img_obj_callback(struct rbd_obj_request *obj_request) |
| { |
| struct rbd_img_request *img_request; |
| u32 which = obj_request->which; |
| bool more = true; |
| |
| rbd_assert(obj_request_img_data_test(obj_request)); |
| img_request = obj_request->img_request; |
| |
| dout("%s: img %p obj %p\n", __func__, img_request, obj_request); |
| rbd_assert(img_request != NULL); |
| rbd_assert(img_request->obj_request_count > 0); |
| rbd_assert(which != BAD_WHICH); |
| rbd_assert(which < img_request->obj_request_count); |
| |
| spin_lock_irq(&img_request->completion_lock); |
| if (which != img_request->next_completion) |
| goto out; |
| |
| for_each_obj_request_from(img_request, obj_request) { |
| rbd_assert(more); |
| rbd_assert(which < img_request->obj_request_count); |
| |
| if (!obj_request_done_test(obj_request)) |
| break; |
| more = rbd_img_obj_end_request(obj_request); |
| which++; |
| } |
| |
| rbd_assert(more ^ (which == img_request->obj_request_count)); |
| img_request->next_completion = which; |
| out: |
| spin_unlock_irq(&img_request->completion_lock); |
| rbd_img_request_put(img_request); |
| |
| if (!more) |
| rbd_img_request_complete(img_request); |
| } |
| |
| /* |
| * Add individual osd ops to the given ceph_osd_request and prepare |
| * them for submission. num_ops is the current number of |
| * osd operations already to the object request. |
| */ |
| static void rbd_img_obj_request_fill(struct rbd_obj_request *obj_request, |
| struct ceph_osd_request *osd_request, |
| enum obj_operation_type op_type, |
| unsigned int num_ops) |
| { |
| struct rbd_img_request *img_request = obj_request->img_request; |
| struct rbd_device *rbd_dev = img_request->rbd_dev; |
| u64 object_size = rbd_obj_bytes(&rbd_dev->header); |
| u64 offset = obj_request->offset; |
| u64 length = obj_request->length; |
| u64 img_end; |
| u16 opcode; |
| |
| if (op_type == OBJ_OP_DISCARD) { |
| if (!offset && length == object_size && |
| (!img_request_layered_test(img_request) || |
| !obj_request_overlaps_parent(obj_request))) { |
| opcode = CEPH_OSD_OP_DELETE; |
| } else if ((offset + length == object_size)) { |
| opcode = CEPH_OSD_OP_TRUNCATE; |
| } else { |
| down_read(&rbd_dev->header_rwsem); |
| img_end = rbd_dev->header.image_size; |
| up_read(&rbd_dev->header_rwsem); |
| |
| if (obj_request->img_offset + length == img_end) |
| opcode = CEPH_OSD_OP_TRUNCATE; |
| else |
| opcode = CEPH_OSD_OP_ZERO; |
| } |
| } else if (op_type == OBJ_OP_WRITE) { |
| if (!offset && length == object_size) |
| opcode = CEPH_OSD_OP_WRITEFULL; |
| else |
| opcode = CEPH_OSD_OP_WRITE; |
| osd_req_op_alloc_hint_init(osd_request, num_ops, |
| object_size, object_size); |
| num_ops++; |
| } else { |
| opcode = CEPH_OSD_OP_READ; |
| } |
| |
| if (opcode == CEPH_OSD_OP_DELETE) |
| osd_req_op_init(osd_request, num_ops, opcode, 0); |
| else |
| osd_req_op_extent_init(osd_request, num_ops, opcode, |
| offset, length, 0, 0); |
| |
| if (obj_request->type == OBJ_REQUEST_BIO) |
| osd_req_op_extent_osd_data_bio(osd_request, num_ops, |
| obj_request->bio_list, length); |
| else if (obj_request->type == OBJ_REQUEST_PAGES) |
| osd_req_op_extent_osd_data_pages(osd_request, num_ops, |
| obj_request->pages, length, |
| offset & ~PAGE_MASK, false, false); |
| |
| /* Discards are also writes */ |
| if (op_type == OBJ_OP_WRITE || op_type == OBJ_OP_DISCARD) |
| rbd_osd_req_format_write(obj_request); |
| else |
| rbd_osd_req_format_read(obj_request); |
| } |
| |
| /* |
| * Split up an image request into one or more object requests, each |
| * to a different object. The "type" parameter indicates whether |
| * "data_desc" is the pointer to the head of a list of bio |
| * structures, or the base of a page array. In either case this |
| * function assumes data_desc describes memory sufficient to hold |
| * all data described by the image request. |
| */ |
| static int rbd_img_request_fill(struct rbd_img_request *img_request, |
| enum obj_request_type type, |
| void *data_desc) |
| { |
| struct rbd_device *rbd_dev = img_request->rbd_dev; |
| struct rbd_obj_request *obj_request = NULL; |
| struct rbd_obj_request *next_obj_request; |
| struct bio *bio_list = NULL; |
| unsigned int bio_offset = 0; |
| struct page **pages = NULL; |
| enum obj_operation_type op_type; |
| u64 img_offset; |
| u64 resid; |
| |
| dout("%s: img %p type %d data_desc %p\n", __func__, img_request, |
| (int)type, data_desc); |
| |
| img_offset = img_request->offset; |
| resid = img_request->length; |
| rbd_assert(resid > 0); |
| op_type = rbd_img_request_op_type(img_request); |
| |
| if (type == OBJ_REQUEST_BIO) { |
| bio_list = data_desc; |
| rbd_assert(img_offset == |
| bio_list->bi_iter.bi_sector << SECTOR_SHIFT); |
| } else if (type == OBJ_REQUEST_PAGES) { |
| pages = data_desc; |
| } |
| |
| while (resid) { |
| struct ceph_osd_request *osd_req; |
| const char *object_name; |
| u64 offset; |
| u64 length; |
| |
| object_name = rbd_segment_name(rbd_dev, img_offset); |
| if (!object_name) |
| goto out_unwind; |
| offset = rbd_segment_offset(rbd_dev, img_offset); |
| length = rbd_segment_length(rbd_dev, img_offset, resid); |
| obj_request = rbd_obj_request_create(object_name, |
| offset, length, type); |
| /* object request has its own copy of the object name */ |
| rbd_segment_name_free(object_name); |
| if (!obj_request) |
| goto out_unwind; |
| |
| /* |
| * set obj_request->img_request before creating the |
| * osd_request so that it gets the right snapc |
| */ |
| rbd_img_obj_request_add(img_request, obj_request); |
| |
| if (type == OBJ_REQUEST_BIO) { |
| unsigned int clone_size; |
| |
| rbd_assert(length <= (u64)UINT_MAX); |
| clone_size = (unsigned int)length; |
| obj_request->bio_list = |
| bio_chain_clone_range(&bio_list, |
| &bio_offset, |
| clone_size, |
| GFP_NOIO); |
| if (!obj_request->bio_list) |
| goto out_unwind; |
| } else if (type == OBJ_REQUEST_PAGES) { |
| unsigned int page_count; |
| |
| obj_request->pages = pages; |
| page_count = (u32)calc_pages_for(offset, length); |
| obj_request->page_count = page_count; |
| if ((offset + length) & ~PAGE_MASK) |
| page_count--; /* more on last page */ |
| pages += page_count; |
| } |
| |
| osd_req = rbd_osd_req_create(rbd_dev, op_type, |
| (op_type == OBJ_OP_WRITE) ? 2 : 1, |
| obj_request); |
| if (!osd_req) |
| goto out_unwind; |
| |
| obj_request->osd_req = osd_req; |
| obj_request->callback = rbd_img_obj_callback; |
| obj_request->img_offset = img_offset; |
| |
| rbd_img_obj_request_fill(obj_request, osd_req, op_type, 0); |
| |
| rbd_img_request_get(img_request); |
| |
| img_offset += length; |
| resid -= length; |
| } |
| |
| return 0; |
| |
| out_unwind: |
| for_each_obj_request_safe(img_request, obj_request, next_obj_request) |
| rbd_img_obj_request_del(img_request, obj_request); |
| |
| return -ENOMEM; |
| } |
| |
| static void |
| rbd_osd_copyup_callback(struct rbd_obj_request *obj_request) |
| { |
| struct rbd_img_request *img_request; |
| struct rbd_device *rbd_dev; |
| struct page **pages; |
| u32 page_count; |
| |
| dout("%s: obj %p\n", __func__, obj_request); |
| |
| rbd_assert(obj_request->type == OBJ_REQUEST_BIO || |
| obj_request->type == OBJ_REQUEST_NODATA); |
| rbd_assert(obj_request_img_data_test(obj_request)); |
| img_request = obj_request->img_request; |
| rbd_assert(img_request); |
| |
| rbd_dev = img_request->rbd_dev; |
| rbd_assert(rbd_dev); |
| |
| pages = obj_request->copyup_pages; |
| rbd_assert(pages != NULL); |
| obj_request->copyup_pages = NULL; |
| page_count = obj_request->copyup_page_count; |
| rbd_assert(page_count); |
| obj_request->copyup_page_count = 0; |
| ceph_release_page_vector(pages, page_count); |
| |
| /* |
| * We want the transfer count to reflect the size of the |
| * original write request. There is no such thing as a |
| * successful short write, so if the request was successful |
| * we can just set it to the originally-requested length. |
| */ |
| if (!obj_request->result) |
| obj_request->xferred = obj_request->length; |
| |
| obj_request_done_set(obj_request); |
| } |
| |
| static void |
| rbd_img_obj_parent_read_full_callback(struct rbd_img_request *img_request) |
| { |
| struct rbd_obj_request *orig_request; |
| struct ceph_osd_request *osd_req; |
| struct ceph_osd_client *osdc; |
| struct rbd_device *rbd_dev; |
| struct page **pages; |
| enum obj_operation_type op_type; |
| u32 page_count; |
| int img_result; |
| u64 parent_length; |
| |
| rbd_assert(img_request_child_test(img_request)); |
| |
| /* First get what we need from the image request */ |
| |
| pages = img_request->copyup_pages; |
| rbd_assert(pages != NULL); |
| img_request->copyup_pages = NULL; |
| page_count = img_request->copyup_page_count; |
| rbd_assert(page_count); |
| img_request->copyup_page_count = 0; |
| |
| orig_request = img_request->obj_request; |
| rbd_assert(orig_request != NULL); |
| rbd_assert(obj_request_type_valid(orig_request->type)); |
| img_result = img_request->result; |
| parent_length = img_request->length; |
| rbd_assert(parent_length == img_request->xferred); |
| rbd_img_request_put(img_request); |
| |
| rbd_assert(orig_request->img_request); |
| rbd_dev = orig_request->img_request->rbd_dev; |
| rbd_assert(rbd_dev); |
| |
| /* |
| * If the overlap has become 0 (most likely because the |
| * image has been flattened) we need to free the pages |
| * and re-submit the original write request. |
| */ |
| if (!rbd_dev->parent_overlap) { |
| struct ceph_osd_client *osdc; |
| |
| ceph_release_page_vector(pages, page_count); |
| osdc = &rbd_dev->rbd_client->client->osdc; |
| img_result = rbd_obj_request_submit(osdc, orig_request); |
| if (!img_result) |
| return; |
| } |
| |
| if (img_result) |
| goto out_err; |
| |
| /* |
| * The original osd request is of no use to use any more. |
| * We need a new one that can hold the three ops in a copyup |
| * request. Allocate the new copyup osd request for the |
| * original request, and release the old one. |
| */ |
| img_result = -ENOMEM; |
| osd_req = rbd_osd_req_create_copyup(orig_request); |
| if (!osd_req) |
| goto out_err; |
| rbd_osd_req_destroy(orig_request->osd_req); |
| orig_request->osd_req = osd_req; |
| orig_request->copyup_pages = pages; |
| orig_request->copyup_page_count = page_count; |
| |
| /* Initialize the copyup op */ |
| |
| osd_req_op_cls_init(osd_req, 0, CEPH_OSD_OP_CALL, "rbd", "copyup"); |
| osd_req_op_cls_request_data_pages(osd_req, 0, pages, parent_length, 0, |
| false, false); |
| |
| /* Add the other op(s) */ |
| |
| op_type = rbd_img_request_op_type(orig_request->img_request); |
| rbd_img_obj_request_fill(orig_request, osd_req, op_type, 1); |
| |
| /* All set, send it off. */ |
| |
| osdc = &rbd_dev->rbd_client->client->osdc; |
| img_result = rbd_obj_request_submit(osdc, orig_request); |
| if (!img_result) |
| return; |
| out_err: |
| /* Record the error code and complete the request */ |
| |
| orig_request->result = img_result; |
| orig_request->xferred = 0; |
| obj_request_done_set(orig_request); |
| rbd_obj_request_complete(orig_request); |
| } |
| |
| /* |
| * Read from the parent image the range of data that covers the |
| * entire target of the given object request. This is used for |
| * satisfying a layered image write request when the target of an |
| * object request from the image request does not exist. |
| * |
| * A page array big enough to hold the returned data is allocated |
| * and supplied to rbd_img_request_fill() as the "data descriptor." |
| * When the read completes, this page array will be transferred to |
| * the original object request for the copyup operation. |
| * |
| * If an error occurs, record it as the result of the original |
| * object request and mark it done so it gets completed. |
| */ |
| static int rbd_img_obj_parent_read_full(struct rbd_obj_request *obj_request) |
| { |
| struct rbd_img_request *img_request = NULL; |
| struct rbd_img_request *parent_request = NULL; |
| struct rbd_device *rbd_dev; |
| u64 img_offset; |
| u64 length; |
| struct page **pages = NULL; |
| u32 page_count; |
| int result; |
| |
| rbd_assert(obj_request_img_data_test(obj_request)); |
| rbd_assert(obj_request_type_valid(obj_request->type)); |
| |
| img_request = obj_request->img_request; |
| rbd_assert(img_request != NULL); |
| rbd_dev = img_request->rbd_dev; |
| rbd_assert(rbd_dev->parent != NULL); |
| |
| /* |
| * Determine the byte range covered by the object in the |
| * child image to which the original request was to be sent. |
| */ |
| img_offset = obj_request->img_offset - obj_request->offset; |
| length = (u64)1 << rbd_dev->header.obj_order; |
| |
| /* |
| * There is no defined parent data beyond the parent |
| * overlap, so limit what we read at that boundary if |
| * necessary. |
| */ |
| if (img_offset + length > rbd_dev->parent_overlap) { |
| rbd_assert(img_offset < rbd_dev->parent_overlap); |
| length = rbd_dev->parent_overlap - img_offset; |
| } |
| |
| /* |
| * Allocate a page array big enough to receive the data read |
| * from the parent. |
| */ |
| page_count = (u32)calc_pages_for(0, length); |
| pages = ceph_alloc_page_vector(page_count, GFP_KERNEL); |
| if (IS_ERR(pages)) { |
| result = PTR_ERR(pages); |
| pages = NULL; |
| goto out_err; |
| } |
| |
| result = -ENOMEM; |
| parent_request = rbd_parent_request_create(obj_request, |
| img_offset, length); |
| if (!parent_request) |
| goto out_err; |
| |
| result = rbd_img_request_fill(parent_request, OBJ_REQUEST_PAGES, pages); |
| if (result) |
| goto out_err; |
| parent_request->copyup_pages = pages; |
| parent_request->copyup_page_count = page_count; |
| |
| parent_request->callback = rbd_img_obj_parent_read_full_callback; |
| result = rbd_img_request_submit(parent_request); |
| if (!result) |
| return 0; |
| |
| parent_request->copyup_pages = NULL; |
| parent_request->copyup_page_count = 0; |
| parent_request->obj_request = NULL; |
| rbd_obj_request_put(obj_request); |
| out_err: |
| if (pages) |
| ceph_release_page_vector(pages, page_count); |
| if (parent_request) |
| rbd_img_request_put(parent_request); |
| obj_request->result = result; |
| obj_request->xferred = 0; |
| obj_request_done_set(obj_request); |
| |
| return result; |
| } |
| |
| static void rbd_img_obj_exists_callback(struct rbd_obj_request *obj_request) |
| { |
| struct rbd_obj_request *orig_request; |
| struct rbd_device *rbd_dev; |
| int result; |
| |
| rbd_assert(!obj_request_img_data_test(obj_request)); |
| |
| /* |
| * All we need from the object request is the original |
| * request and the result of the STAT op. Grab those, then |
| * we're done with the request. |
| */ |
| orig_request = obj_request->obj_request; |
| obj_request->obj_request = NULL; |
| rbd_obj_request_put(orig_request); |
| rbd_assert(orig_request); |
| rbd_assert(orig_request->img_request); |
| |
| result = obj_request->result; |
| obj_request->result = 0; |
| |
| dout("%s: obj %p for obj %p result %d %llu/%llu\n", __func__, |
| obj_request, orig_request, result, |
| obj_request->xferred, obj_request->length); |
| rbd_obj_request_put(obj_request); |
| |
| /* |
| * If the overlap has become 0 (most likely because the |
| * image has been flattened) we need to free the pages |
| * and re-submit the original write request. |
| */ |
| rbd_dev = orig_request->img_request->rbd_dev; |
| if (!rbd_dev->parent_overlap) { |
| struct ceph_osd_client *osdc; |
| |
| osdc = &rbd_dev->rbd_client->client->osdc; |
| result = rbd_obj_request_submit(osdc, orig_request); |
| if (!result) |
| return; |
| } |
| |
| /* |
| * Our only purpose here is to determine whether the object |
| * exists, and we don't want to treat the non-existence as |
| * an error. If something else comes back, transfer the |
| * error to the original request and complete it now. |
| */ |
| if (!result) { |
| obj_request_existence_set(orig_request, true); |
| } else if (result == -ENOENT) { |
| obj_request_existence_set(orig_request, false); |
| } else if (result) { |
| orig_request->result = result; |
| goto out; |
| } |
| |
| /* |
| * Resubmit the original request now that we have recorded |
| * whether the target object exists. |
| */ |
| orig_request->result = rbd_img_obj_request_submit(orig_request); |
| out: |
| if (orig_request->result) |
| rbd_obj_request_complete(orig_request); |
| } |
| |
| static int rbd_img_obj_exists_submit(struct rbd_obj_request *obj_request) |
| { |
| struct rbd_obj_request *stat_request; |
| struct rbd_device *rbd_dev; |
| struct ceph_osd_client *osdc; |
| struct page **pages = NULL; |
| u32 page_count; |
| size_t size; |
| int ret; |
| |
| /* |
| * The response data for a STAT call consists of: |
| * le64 length; |
| * struct { |
| * le32 tv_sec; |
| * le32 tv_nsec; |
| * } mtime; |
| */ |
| size = sizeof (__le64) + sizeof (__le32) + sizeof (__le32); |
| page_count = (u32)calc_pages_for(0, size); |
| pages = ceph_alloc_page_vector(page_count, GFP_KERNEL); |
| if (IS_ERR(pages)) |
| return PTR_ERR(pages); |
| |
| ret = -ENOMEM; |
| stat_request = rbd_obj_request_create(obj_request->object_name, 0, 0, |
| OBJ_REQUEST_PAGES); |
| if (!stat_request) |
| goto out; |
| |
| rbd_obj_request_get(obj_request); |
| stat_request->obj_request = obj_request; |
| stat_request->pages = pages; |
| stat_request->page_count = page_count; |
| |
| rbd_assert(obj_request->img_request); |
| rbd_dev = obj_request->img_request->rbd_dev; |
| stat_request->osd_req = rbd_osd_req_create(rbd_dev, OBJ_OP_READ, 1, |
| stat_request); |
| if (!stat_request->osd_req) |
| goto out; |
| stat_request->callback = rbd_img_obj_exists_callback; |
| |
| osd_req_op_init(stat_request->osd_req, 0, CEPH_OSD_OP_STAT, 0); |
| osd_req_op_raw_data_in_pages(stat_request->osd_req, 0, pages, size, 0, |
| false, false); |
| rbd_osd_req_format_read(stat_request); |
| |
| osdc = &rbd_dev->rbd_client->client->osdc; |
| ret = rbd_obj_request_submit(osdc, stat_request); |
| out: |
| if (ret) |
| rbd_obj_request_put(obj_request); |
| |
| return ret; |
| } |
| |
| static bool img_obj_request_simple(struct rbd_obj_request *obj_request) |
| { |
| struct rbd_img_request *img_request; |
| struct rbd_device *rbd_dev; |
| |
| rbd_assert(obj_request_img_data_test(obj_request)); |
| |
| img_request = obj_request->img_request; |
| rbd_assert(img_request); |
| rbd_dev = img_request->rbd_dev; |
| |
| /* Reads */ |
| if (!img_request_write_test(img_request) && |
| !img_request_discard_test(img_request)) |
| return true; |
| |
| /* Non-layered writes */ |
| if (!img_request_layered_test(img_request)) |
| return true; |
| |
| /* |
| * Layered writes outside of the parent overlap range don't |
| * share any data with the parent. |
| */ |
| if (!obj_request_overlaps_parent(obj_request)) |
| return true; |
| |
| /* |
| * Entire-object layered writes - we will overwrite whatever |
| * parent data there is anyway. |
| */ |
| if (!obj_request->offset && |
| obj_request->length == rbd_obj_bytes(&rbd_dev->header)) |
| return true; |
| |
| /* |
| * If the object is known to already exist, its parent data has |
| * already been copied. |
| */ |
| if (obj_request_known_test(obj_request) && |
| obj_request_exists_test(obj_request)) |
| return true; |
| |
| return false; |
| } |
| |
| static int rbd_img_obj_request_submit(struct rbd_obj_request *obj_request) |
| { |
| if (img_obj_request_simple(obj_request)) { |
| struct rbd_device *rbd_dev; |
| struct ceph_osd_client *osdc; |
| |
| rbd_dev = obj_request->img_request->rbd_dev; |
| osdc = &rbd_dev->rbd_client->client->osdc; |
| |
| return rbd_obj_request_submit(osdc, obj_request); |
| } |
| |
| /* |
| * It's a layered write. The target object might exist but |
| * we may not know that yet. If we know it doesn't exist, |
| * start by reading the data for the full target object from |
| * the parent so we can use it for a copyup to the target. |
| */ |
| if (obj_request_known_test(obj_request)) |
| return rbd_img_obj_parent_read_full(obj_request); |
| |
| /* We don't know whether the target exists. Go find out. */ |
| |
| return rbd_img_obj_exists_submit(obj_request); |
| } |
| |
| static int rbd_img_request_submit(struct rbd_img_request *img_request) |
| { |
| struct rbd_obj_request *obj_request; |
| struct rbd_obj_request *next_obj_request; |
| int ret = 0; |
| |
| dout("%s: img %p\n", __func__, img_request); |
| |
| rbd_img_request_get(img_request); |
| for_each_obj_request_safe(img_request, obj_request, next_obj_request) { |
| ret = rbd_img_obj_request_submit(obj_request); |
| if (ret) |
| goto out_put_ireq; |
| } |
| |
| out_put_ireq: |
| rbd_img_request_put(img_request); |
| return ret; |
| } |
| |
| static void rbd_img_parent_read_callback(struct rbd_img_request *img_request) |
| { |
| struct rbd_obj_request *obj_request; |
| struct rbd_device *rbd_dev; |
| u64 obj_end; |
| u64 img_xferred; |
| int img_result; |
| |
| rbd_assert(img_request_child_test(img_request)); |
| |
| /* First get what we need from the image request and release it */ |
| |
| obj_request = img_request->obj_request; |
| img_xferred = img_request->xferred; |
| img_result = img_request->result; |
| rbd_img_request_put(img_request); |
| |
| /* |
| * If the overlap has become 0 (most likely because the |
| * image has been flattened) we need to re-submit the |
| * original request. |
| */ |
| rbd_assert(obj_request); |
| rbd_assert(obj_request->img_request); |
| rbd_dev = obj_request->img_request->rbd_dev; |
| if (!rbd_dev->parent_overlap) { |
| struct ceph_osd_client *osdc; |
| |
| osdc = &rbd_dev->rbd_client->client->osdc; |
| img_result = rbd_obj_request_submit(osdc, obj_request); |
| if (!img_result) |
| return; |
| } |
| |
| obj_request->result = img_result; |
| if (obj_request->result) |
| goto out; |
| |
| /* |
| * We need to zero anything beyond the parent overlap |
| * boundary. Since rbd_img_obj_request_read_callback() |
| * will zero anything beyond the end of a short read, an |
| * easy way to do this is to pretend the data from the |
| * parent came up short--ending at the overlap boundary. |
| */ |
| rbd_assert(obj_request->img_offset < U64_MAX - obj_request->length); |
| obj_end = obj_request->img_offset + obj_request->length; |
| if (obj_end > rbd_dev->parent_overlap) { |
| u64 xferred = 0; |
| |
| if (obj_request->img_offset < rbd_dev->parent_overlap) |
| xferred = rbd_dev->parent_overlap - |
| obj_request->img_offset; |
| |
| obj_request->xferred = min(img_xferred, xferred); |
| } else { |
| obj_request->xferred = img_xferred; |
| } |
| out: |
| rbd_img_obj_request_read_callback(obj_request); |
| rbd_obj_request_complete(obj_request); |
| } |
| |
| static void rbd_img_parent_read(struct rbd_obj_request *obj_request) |
| { |
| struct rbd_img_request *img_request; |
| int result; |
| |
| rbd_assert(obj_request_img_data_test(obj_request)); |
| rbd_assert(obj_request->img_request != NULL); |
| rbd_assert(obj_request->result == (s32) -ENOENT); |
| rbd_assert(obj_request_type_valid(obj_request->type)); |
| |
| /* rbd_read_finish(obj_request, obj_request->length); */ |
| img_request = rbd_parent_request_create(obj_request, |
| obj_request->img_offset, |
| obj_request->length); |
| result = -ENOMEM; |
| if (!img_request) |
| goto out_err; |
| |
| if (obj_request->type == OBJ_REQUEST_BIO) |
| result = rbd_img_request_fill(img_request, OBJ_REQUEST_BIO, |
| obj_request->bio_list); |
| else |
| result = rbd_img_request_fill(img_request, OBJ_REQUEST_PAGES, |
| obj_request->pages); |
| if (result) |
| goto out_err; |
| |
| img_request->callback = rbd_img_parent_read_callback; |
| result = rbd_img_request_submit(img_request); |
| if (result) |
| goto out_err; |
| |
| return; |
| out_err: |
| if (img_request) |
| rbd_img_request_put(img_request); |
| obj_request->result = result; |
| obj_request->xferred = 0; |
| obj_request_done_set(obj_request); |
| } |
| |
| static int rbd_dev_header_watch_sync(struct rbd_device *rbd_dev); |
| static void __rbd_dev_header_unwatch_sync(struct rbd_device *rbd_dev); |
| |
| static void rbd_watch_cb(void *arg, u64 notify_id, u64 cookie, |
| u64 notifier_id, void *data, size_t data_len) |
| { |
| struct rbd_device *rbd_dev = arg; |
| struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; |
| int ret; |
| |
| dout("%s rbd_dev %p cookie %llu notify_id %llu\n", __func__, rbd_dev, |
| cookie, notify_id); |
| |
| /* |
| * Until adequate refresh error handling is in place, there is |
| * not much we can do here, except warn. |
| * |
| * See http://tracker.ceph.com/issues/5040 |
| */ |
| ret = rbd_dev_refresh(rbd_dev); |
| if (ret) |
| rbd_warn(rbd_dev, "refresh failed: %d", ret); |
| |
| ret = ceph_osdc_notify_ack(osdc, &rbd_dev->header_oid, |
| &rbd_dev->header_oloc, notify_id, cookie, |
| NULL, 0); |
| if (ret) |
| rbd_warn(rbd_dev, "notify_ack ret %d", ret); |
| } |
| |
| static void rbd_watch_errcb(void *arg, u64 cookie, int err) |
| { |
| struct rbd_device *rbd_dev = arg; |
| int ret; |
| |
| rbd_warn(rbd_dev, "encountered watch error: %d", err); |
| |
| __rbd_dev_header_unwatch_sync(rbd_dev); |
| |
| ret = rbd_dev_header_watch_sync(rbd_dev); |
| if (ret) { |
| rbd_warn(rbd_dev, "failed to reregister watch: %d", ret); |
| return; |
| } |
| |
| ret = rbd_dev_refresh(rbd_dev); |
| if (ret) |
| rbd_warn(rbd_dev, "reregisteration refresh failed: %d", ret); |
| } |
| |
| /* |
| * Initiate a watch request, synchronously. |
| */ |
| static int rbd_dev_header_watch_sync(struct rbd_device *rbd_dev) |
| { |
| struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; |
| struct ceph_osd_linger_request *handle; |
| |
| rbd_assert(!rbd_dev->watch_handle); |
| |
| handle = ceph_osdc_watch(osdc, &rbd_dev->header_oid, |
| &rbd_dev->header_oloc, rbd_watch_cb, |
| rbd_watch_errcb, rbd_dev); |
| if (IS_ERR(handle)) |
| return PTR_ERR(handle); |
| |
| rbd_dev->watch_handle = handle; |
| return 0; |
| } |
| |
| static void __rbd_dev_header_unwatch_sync(struct rbd_device *rbd_dev) |
| { |
| struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; |
| int ret; |
| |
| if (!rbd_dev->watch_handle) |
| return; |
| |
| ret = ceph_osdc_unwatch(osdc, rbd_dev->watch_handle); |
| if (ret) |
| rbd_warn(rbd_dev, "failed to unwatch: %d", ret); |
| |
| rbd_dev->watch_handle = NULL; |
| } |
| |
| /* |
| * Tear down a watch request, synchronously. |
| */ |
| static void rbd_dev_header_unwatch_sync(struct rbd_device *rbd_dev) |
| { |
| __rbd_dev_header_unwatch_sync(rbd_dev); |
| |
| dout("%s flushing notifies\n", __func__); |
| ceph_osdc_flush_notifies(&rbd_dev->rbd_client->client->osdc); |
| } |
| |
| /* |
| * Synchronous osd object method call. Returns the number of bytes |
| * returned in the outbound buffer, or a negative error code. |
| */ |
| static int rbd_obj_method_sync(struct rbd_device *rbd_dev, |
| const char *object_name, |
| const char *class_name, |
| const char *method_name, |
| const void *outbound, |
| size_t outbound_size, |
| void *inbound, |
| size_t inbound_size) |
| { |
| struct ceph_osd_client *osdc = &rbd_dev->rbd_client->client->osdc; |
| struct rbd_obj_request *obj_request; |
| struct page **pages; |
| u32 page_count; |
| int ret; |
| |
| /* |
| * Method calls are ultimately read operations. The result |
| * should placed into the inbound buffer provided. They |
| * also supply outbound data--parameters for the object |
| * method. Currently if this is present it will be a |
| * snapshot id. |
| */ |
| page_count = (u32)calc_pages_for(0, inbound_size); |
| pages = ceph_alloc_page_vector(page_count, GFP_KERNEL); |
| if (IS_ERR(pages)) |
| return PTR_ERR(pages); |
| |
| ret = -ENOMEM; |
| obj_request = rbd_obj_request_create(object_name, 0, inbound_size, |
| OBJ_REQUEST_PAGES); |
| if (!obj_request) |
| goto out; |
| |
| obj_request->pages = pages; |
| obj_request->page_count = page_count; |
| |
| obj_request->osd_req = rbd_osd_req_create(rbd_dev, OBJ_OP_READ, 1, |
| obj_request); |
| if (!obj_request->osd_req) |
| goto out; |
| |
| osd_req_op_cls_init(obj_request->osd_req, 0, CEPH_OSD_OP_CALL, |
| class_name, method_name); |
| if (outbound_size) { |
| struct ceph_pagelist |