From fae65ef3a148079103ae935107c62f7830ab52c5 Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Tue, 28 Mar 2023 10:45:49 +0200 Subject: [PATCH 1/7] xen/pciback: don't call pcistub_device_put() under lock pcistub_device_put() shouldn't be called under spinlock, as it can sleep. For this reason pcistub_device_get_pci_dev() needs to be modified: instead of always calling pcistub_device_get() just do the call of pcistub_device_get() only if it is really needed. This removes the need to call pcistub_device_put(). Reported-by: Dan Carpenter Link: https://lore.kernel.org/lkml/Y+JUIl64UDmdkboh@kadam/ Signed-off-by: Juergen Gross Reviewed-by: Oleksandr Tyshchenko Link: https://lore.kernel.org/r/20230328084549.20695-1-jgross@suse.com Signed-off-by: Juergen Gross --- drivers/xen/xen-pciback/pci_stub.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c index bba527620507..e34b623e4b41 100644 --- a/drivers/xen/xen-pciback/pci_stub.c +++ b/drivers/xen/xen-pciback/pci_stub.c @@ -194,8 +194,6 @@ static struct pci_dev *pcistub_device_get_pci_dev(struct xen_pcibk_device *pdev, struct pci_dev *pci_dev = NULL; unsigned long flags; - pcistub_device_get(psdev); - spin_lock_irqsave(&psdev->lock, flags); if (!psdev->pdev) { psdev->pdev = pdev; @@ -203,8 +201,8 @@ static struct pci_dev *pcistub_device_get_pci_dev(struct xen_pcibk_device *pdev, } spin_unlock_irqrestore(&psdev->lock, flags); - if (!pci_dev) - pcistub_device_put(psdev); + if (pci_dev) + pcistub_device_get(psdev); return pci_dev; } From b2c042cc802fe96d431821bf1cf2f0f04a3eda7d Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Tue, 28 Mar 2023 10:46:02 +0200 Subject: [PATCH 2/7] xen/scsiback: don't call scsiback_free_translation_entry() under lock scsiback_free_translation_entry() shouldn't be called under spinlock, as it can sleep. This requires to split removing a translation entry from the v2p list from actually calling kref_put() for the entry. Reported-by: Dan Carpenter Link: https://lore.kernel.org/lkml/Y+JUIl64UDmdkboh@kadam/ Signed-off-by: Juergen Gross Reviewed-by: Oleksandr Tyshchenko Link: https://lore.kernel.org/r/20230328084602.20729-1-jgross@suse.com Signed-off-by: Juergen Gross --- drivers/xen/xen-scsiback.c | 27 ++++++++++++++------------- 1 file changed, 14 insertions(+), 13 deletions(-) diff --git a/drivers/xen/xen-scsiback.c b/drivers/xen/xen-scsiback.c index 954188b0b858..294f29cdc7aa 100644 --- a/drivers/xen/xen-scsiback.c +++ b/drivers/xen/xen-scsiback.c @@ -1010,12 +1010,6 @@ out_free: return err; } -static void __scsiback_del_translation_entry(struct v2p_entry *entry) -{ - list_del(&entry->l); - kref_put(&entry->kref, scsiback_free_translation_entry); -} - /* Delete the translation entry specified */ @@ -1024,18 +1018,20 @@ static int scsiback_del_translation_entry(struct vscsibk_info *info, { struct v2p_entry *entry; unsigned long flags; - int ret = 0; spin_lock_irqsave(&info->v2p_lock, flags); /* Find out the translation entry specified */ entry = scsiback_chk_translation_entry(info, v); if (entry) - __scsiback_del_translation_entry(entry); - else - ret = -ENOENT; + list_del(&entry->l); spin_unlock_irqrestore(&info->v2p_lock, flags); - return ret; + + if (!entry) + return -ENOENT; + + kref_put(&entry->kref, scsiback_free_translation_entry); + return 0; } static void scsiback_do_add_lun(struct vscsibk_info *info, const char *state, @@ -1239,14 +1235,19 @@ static void scsiback_release_translation_entry(struct vscsibk_info *info) { struct v2p_entry *entry, *tmp; struct list_head *head = &(info->v2p_entry_lists); + struct list_head tmp_list; unsigned long flags; spin_lock_irqsave(&info->v2p_lock, flags); - list_for_each_entry_safe(entry, tmp, head, l) - __scsiback_del_translation_entry(entry); + list_cut_before(&tmp_list, head, head); spin_unlock_irqrestore(&info->v2p_lock, flags); + + list_for_each_entry_safe(entry, tmp, &tmp_list, l) { + list_del(&entry->l); + kref_put(&entry->kref, scsiback_free_translation_entry); + } } static void scsiback_remove(struct xenbus_device *dev) From c66bb48edd58c3a22072b4f68312c225dc1b0009 Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Mon, 3 Apr 2023 11:27:11 +0200 Subject: [PATCH 3/7] xen/pvcalls: don't call bind_evtchn_to_irqhandler() under lock bind_evtchn_to_irqhandler() shouldn't be called under spinlock, as it can sleep. This requires to move the calls of create_active() out of the locked regions. This is no problem, as the worst which could happen would be a spurious call of the interrupt handler, causing a spurious wake_up(). Reported-by: Dan Carpenter Link: https://lore.kernel.org/lkml/Y+JUIl64UDmdkboh@kadam/ Signed-off-by: Juergen Gross Reviewed-by: Oleksandr Tyshchenko Reviewed-by: Stefano Stabellini Link: https://lore.kernel.org/r/20230403092711.15285-1-jgross@suse.com Signed-off-by: Juergen Gross --- drivers/xen/pvcalls-front.c | 60 ++++++++++++++++++++----------------- 1 file changed, 33 insertions(+), 27 deletions(-) diff --git a/drivers/xen/pvcalls-front.c b/drivers/xen/pvcalls-front.c index d5d589bda243..b72ee9379d77 100644 --- a/drivers/xen/pvcalls-front.c +++ b/drivers/xen/pvcalls-front.c @@ -227,22 +227,30 @@ again: static void free_active_ring(struct sock_mapping *map); -static void pvcalls_front_free_map(struct pvcalls_bedata *bedata, - struct sock_mapping *map) +static void pvcalls_front_destroy_active(struct pvcalls_bedata *bedata, + struct sock_mapping *map) { int i; unbind_from_irqhandler(map->active.irq, map); - spin_lock(&bedata->socket_lock); - if (!list_empty(&map->list)) - list_del_init(&map->list); - spin_unlock(&bedata->socket_lock); + if (bedata) { + spin_lock(&bedata->socket_lock); + if (!list_empty(&map->list)) + list_del_init(&map->list); + spin_unlock(&bedata->socket_lock); + } for (i = 0; i < (1 << PVCALLS_RING_ORDER); i++) gnttab_end_foreign_access(map->active.ring->ref[i], NULL); gnttab_end_foreign_access(map->active.ref, NULL); free_active_ring(map); +} + +static void pvcalls_front_free_map(struct pvcalls_bedata *bedata, + struct sock_mapping *map) +{ + pvcalls_front_destroy_active(bedata, map); kfree(map); } @@ -433,19 +441,18 @@ int pvcalls_front_connect(struct socket *sock, struct sockaddr *addr, pvcalls_exit_sock(sock); return ret; } + ret = create_active(map, &evtchn); + if (ret < 0) { + free_active_ring(map); + pvcalls_exit_sock(sock); + return ret; + } spin_lock(&bedata->socket_lock); ret = get_request(bedata, &req_id); if (ret < 0) { spin_unlock(&bedata->socket_lock); - free_active_ring(map); - pvcalls_exit_sock(sock); - return ret; - } - ret = create_active(map, &evtchn); - if (ret < 0) { - spin_unlock(&bedata->socket_lock); - free_active_ring(map); + pvcalls_front_destroy_active(NULL, map); pvcalls_exit_sock(sock); return ret; } @@ -821,28 +828,27 @@ int pvcalls_front_accept(struct socket *sock, struct socket *newsock, int flags) pvcalls_exit_sock(sock); return ret; } - spin_lock(&bedata->socket_lock); - ret = get_request(bedata, &req_id); - if (ret < 0) { - clear_bit(PVCALLS_FLAG_ACCEPT_INFLIGHT, - (void *)&map->passive.flags); - spin_unlock(&bedata->socket_lock); - free_active_ring(map2); - kfree(map2); - pvcalls_exit_sock(sock); - return ret; - } - ret = create_active(map2, &evtchn); if (ret < 0) { free_active_ring(map2); kfree(map2); clear_bit(PVCALLS_FLAG_ACCEPT_INFLIGHT, (void *)&map->passive.flags); - spin_unlock(&bedata->socket_lock); pvcalls_exit_sock(sock); return ret; } + + spin_lock(&bedata->socket_lock); + ret = get_request(bedata, &req_id); + if (ret < 0) { + clear_bit(PVCALLS_FLAG_ACCEPT_INFLIGHT, + (void *)&map->passive.flags); + spin_unlock(&bedata->socket_lock); + pvcalls_front_free_map(bedata, map2); + pvcalls_exit_sock(sock); + return ret; + } + list_add_tail(&map2->list, &bedata->socket_mappings); req = RING_GET_REQUEST(&bedata->ring, req_id); From 6935321eccf32555e6f7e6d29f4cccf84a5c1e3a Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Mon, 12 Dec 2022 09:41:34 +0100 Subject: [PATCH 4/7] xen/blkback: fix white space code style issues MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Signed-off-by: Juergen Gross Acked-by: Roger Pau Monné Signed-off-by: Juergen Gross --- drivers/block/xen-blkback/blkback.c | 2 +- drivers/block/xen-blkback/common.h | 6 +++--- 2 files changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c index a5cf7f1e871c..6e2163aaf362 100644 --- a/drivers/block/xen-blkback/blkback.c +++ b/drivers/block/xen-blkback/blkback.c @@ -891,7 +891,7 @@ next: out: for (i = last_map; i < num; i++) { /* Don't zap current batch's valid persistent grants. */ - if(i >= map_until) + if (i >= map_until) pages[i]->persistent_gnt = NULL; pages[i]->handle = BLKBACK_INVALID_HANDLE; } diff --git a/drivers/block/xen-blkback/common.h b/drivers/block/xen-blkback/common.h index a28473470e66..9a13a6b420a6 100644 --- a/drivers/block/xen-blkback/common.h +++ b/drivers/block/xen-blkback/common.h @@ -296,7 +296,7 @@ struct xen_blkif_ring { struct work_struct free_work; /* Thread shutdown wait queue. */ wait_queue_head_t shutdown_wq; - struct xen_blkif *blkif; + struct xen_blkif *blkif; }; struct xen_blkif { @@ -315,7 +315,7 @@ struct xen_blkif { atomic_t drain; struct work_struct free_work; - unsigned int nr_ring_pages; + unsigned int nr_ring_pages; bool multi_ref; /* All rings for this device. */ struct xen_blkif_ring *rings; @@ -329,7 +329,7 @@ struct seg_buf { }; struct grant_page { - struct page *page; + struct page *page; struct persistent_gnt *persistent_gnt; grant_handle_t handle; grant_ref_t gref; From 656f3c1d7966ea65f9b51d17db3008ce5dbb4090 Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Mon, 12 Dec 2022 09:43:28 +0100 Subject: [PATCH 5/7] xen/blkback: remove stale prototype MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit There is no function xen_blkif_purge_persistent(), so remove its prototype from common.h. Signed-off-by: Juergen Gross Acked-by: Roger Pau Monné Signed-off-by: Juergen Gross --- drivers/block/xen-blkback/common.h | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/block/xen-blkback/common.h b/drivers/block/xen-blkback/common.h index 9a13a6b420a6..fab8a8dee0da 100644 --- a/drivers/block/xen-blkback/common.h +++ b/drivers/block/xen-blkback/common.h @@ -384,7 +384,6 @@ void xen_blkif_xenbus_fini(void); irqreturn_t xen_blkif_be_int(int irq, void *dev_id); int xen_blkif_schedule(void *arg); -int xen_blkif_purge_persistent(void *arg); void xen_blkbk_free_caches(struct xen_blkif_ring *ring); int xen_blkbk_flush_diskcache(struct xenbus_transaction xbt, From e7b4c07d4b42676691f3c815f05c1bbf071dc718 Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Mon, 12 Dec 2022 10:37:42 +0100 Subject: [PATCH 6/7] xen/blkback: simplify free_persistent_gnts() interface MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The interface of free_persistent_gnts() can be simplified, as there is only a single caller of free_persistent_gnts() and the 2nd and 3rd parameters are easily obtainable via the ring pointer, which is passed as the first parameter anyway. Signed-off-by: Juergen Gross Acked-by: Roger Pau Monné Signed-off-by: Juergen Gross --- drivers/block/xen-blkback/blkback.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c index 6e2163aaf362..243712b59a05 100644 --- a/drivers/block/xen-blkback/blkback.c +++ b/drivers/block/xen-blkback/blkback.c @@ -239,9 +239,9 @@ static void put_persistent_gnt(struct xen_blkif_ring *ring, atomic_dec(&ring->persistent_gnt_in_use); } -static void free_persistent_gnts(struct xen_blkif_ring *ring, struct rb_root *root, - unsigned int num) +static void free_persistent_gnts(struct xen_blkif_ring *ring) { + struct rb_root *root = &ring->persistent_gnts; struct gnttab_unmap_grant_ref unmap[BLKIF_MAX_SEGMENTS_PER_REQUEST]; struct page *pages[BLKIF_MAX_SEGMENTS_PER_REQUEST]; struct persistent_gnt *persistent_gnt; @@ -249,6 +249,9 @@ static void free_persistent_gnts(struct xen_blkif_ring *ring, struct rb_root *ro int segs_to_unmap = 0; struct gntab_unmap_queue_data unmap_data; + if (RB_EMPTY_ROOT(root)) + return; + unmap_data.pages = pages; unmap_data.unmap_ops = unmap; unmap_data.kunmap_ops = NULL; @@ -277,9 +280,11 @@ static void free_persistent_gnts(struct xen_blkif_ring *ring, struct rb_root *ro rb_erase(&persistent_gnt->node, root); kfree(persistent_gnt); - num--; + ring->persistent_gnt_c--; } - BUG_ON(num != 0); + + BUG_ON(!RB_EMPTY_ROOT(&ring->persistent_gnts)); + BUG_ON(ring->persistent_gnt_c != 0); } void xen_blkbk_unmap_purged_grants(struct work_struct *work) @@ -631,12 +636,7 @@ purge_gnt_list: void xen_blkbk_free_caches(struct xen_blkif_ring *ring) { /* Free all persistent grant pages */ - if (!RB_EMPTY_ROOT(&ring->persistent_gnts)) - free_persistent_gnts(ring, &ring->persistent_gnts, - ring->persistent_gnt_c); - - BUG_ON(!RB_EMPTY_ROOT(&ring->persistent_gnts)); - ring->persistent_gnt_c = 0; + free_persistent_gnts(ring); /* Since we are shutting down remove all pages from the buffer */ gnttab_page_cache_shrink(&ring->free_pages, 0 /* All */); From cbfac7707ba16619006a4fd60faac46303fd2f3e Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Fri, 16 Dec 2022 14:49:18 +0100 Subject: [PATCH 7/7] xen/blkback: move blkif_get_x86_*_req() into blkback.c MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit There is no need to have the functions blkif_get_x86_32_req() and blkif_get_x86_64_req() in a header file, as they are used in one place only. So move them into the using source file and drop the inline qualifier. While at it fix some style issues, and simplify the code by variable reusing and using min() instead of open coding it. Instead of using barrier() use READ_ONCE() for avoiding multiple reads of nr_segments. Signed-off-by: Juergen Gross Acked-by: Roger Pau Monné Signed-off-by: Juergen Gross --- drivers/block/xen-blkback/blkback.c | 104 ++++++++++++++++++++++++++++ drivers/block/xen-blkback/common.h | 96 ------------------------- 2 files changed, 104 insertions(+), 96 deletions(-) diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c index 243712b59a05..c362f4ad80ab 100644 --- a/drivers/block/xen-blkback/blkback.c +++ b/drivers/block/xen-blkback/blkback.c @@ -1072,7 +1072,111 @@ static void end_block_io_op(struct bio *bio) bio_put(bio); } +static void blkif_get_x86_32_req(struct blkif_request *dst, + const struct blkif_x86_32_request *src) +{ + unsigned int i, n; + dst->operation = READ_ONCE(src->operation); + + switch (dst->operation) { + case BLKIF_OP_READ: + case BLKIF_OP_WRITE: + case BLKIF_OP_WRITE_BARRIER: + case BLKIF_OP_FLUSH_DISKCACHE: + dst->u.rw.nr_segments = READ_ONCE(src->u.rw.nr_segments); + dst->u.rw.handle = src->u.rw.handle; + dst->u.rw.id = src->u.rw.id; + dst->u.rw.sector_number = src->u.rw.sector_number; + n = min_t(unsigned int, BLKIF_MAX_SEGMENTS_PER_REQUEST, + dst->u.rw.nr_segments); + for (i = 0; i < n; i++) + dst->u.rw.seg[i] = src->u.rw.seg[i]; + break; + + case BLKIF_OP_DISCARD: + dst->u.discard.flag = src->u.discard.flag; + dst->u.discard.id = src->u.discard.id; + dst->u.discard.sector_number = src->u.discard.sector_number; + dst->u.discard.nr_sectors = src->u.discard.nr_sectors; + break; + + case BLKIF_OP_INDIRECT: + dst->u.indirect.indirect_op = src->u.indirect.indirect_op; + dst->u.indirect.nr_segments = + READ_ONCE(src->u.indirect.nr_segments); + dst->u.indirect.handle = src->u.indirect.handle; + dst->u.indirect.id = src->u.indirect.id; + dst->u.indirect.sector_number = src->u.indirect.sector_number; + n = min(MAX_INDIRECT_PAGES, + INDIRECT_PAGES(dst->u.indirect.nr_segments)); + for (i = 0; i < n; i++) + dst->u.indirect.indirect_grefs[i] = + src->u.indirect.indirect_grefs[i]; + break; + + default: + /* + * Don't know how to translate this op. Only get the + * ID so failure can be reported to the frontend. + */ + dst->u.other.id = src->u.other.id; + break; + } +} + +static void blkif_get_x86_64_req(struct blkif_request *dst, + const struct blkif_x86_64_request *src) +{ + unsigned int i, n; + + dst->operation = READ_ONCE(src->operation); + + switch (dst->operation) { + case BLKIF_OP_READ: + case BLKIF_OP_WRITE: + case BLKIF_OP_WRITE_BARRIER: + case BLKIF_OP_FLUSH_DISKCACHE: + dst->u.rw.nr_segments = READ_ONCE(src->u.rw.nr_segments); + dst->u.rw.handle = src->u.rw.handle; + dst->u.rw.id = src->u.rw.id; + dst->u.rw.sector_number = src->u.rw.sector_number; + n = min_t(unsigned int, BLKIF_MAX_SEGMENTS_PER_REQUEST, + dst->u.rw.nr_segments); + for (i = 0; i < n; i++) + dst->u.rw.seg[i] = src->u.rw.seg[i]; + break; + + case BLKIF_OP_DISCARD: + dst->u.discard.flag = src->u.discard.flag; + dst->u.discard.id = src->u.discard.id; + dst->u.discard.sector_number = src->u.discard.sector_number; + dst->u.discard.nr_sectors = src->u.discard.nr_sectors; + break; + + case BLKIF_OP_INDIRECT: + dst->u.indirect.indirect_op = src->u.indirect.indirect_op; + dst->u.indirect.nr_segments = + READ_ONCE(src->u.indirect.nr_segments); + dst->u.indirect.handle = src->u.indirect.handle; + dst->u.indirect.id = src->u.indirect.id; + dst->u.indirect.sector_number = src->u.indirect.sector_number; + n = min(MAX_INDIRECT_PAGES, + INDIRECT_PAGES(dst->u.indirect.nr_segments)); + for (i = 0; i < n; i++) + dst->u.indirect.indirect_grefs[i] = + src->u.indirect.indirect_grefs[i]; + break; + + default: + /* + * Don't know how to translate this op. Only get the + * ID so failure can be reported to the frontend. + */ + dst->u.other.id = src->u.other.id; + break; + } +} /* * Function to copy the from the ring buffer the 'struct blkif_request' diff --git a/drivers/block/xen-blkback/common.h b/drivers/block/xen-blkback/common.h index fab8a8dee0da..40f67bfc052d 100644 --- a/drivers/block/xen-blkback/common.h +++ b/drivers/block/xen-blkback/common.h @@ -394,100 +394,4 @@ int xen_blkbk_barrier(struct xenbus_transaction xbt, struct xenbus_device *xen_blkbk_xenbus(struct backend_info *be); void xen_blkbk_unmap_purged_grants(struct work_struct *work); -static inline void blkif_get_x86_32_req(struct blkif_request *dst, - struct blkif_x86_32_request *src) -{ - int i, n = BLKIF_MAX_SEGMENTS_PER_REQUEST, j; - dst->operation = READ_ONCE(src->operation); - switch (dst->operation) { - case BLKIF_OP_READ: - case BLKIF_OP_WRITE: - case BLKIF_OP_WRITE_BARRIER: - case BLKIF_OP_FLUSH_DISKCACHE: - dst->u.rw.nr_segments = src->u.rw.nr_segments; - dst->u.rw.handle = src->u.rw.handle; - dst->u.rw.id = src->u.rw.id; - dst->u.rw.sector_number = src->u.rw.sector_number; - barrier(); - if (n > dst->u.rw.nr_segments) - n = dst->u.rw.nr_segments; - for (i = 0; i < n; i++) - dst->u.rw.seg[i] = src->u.rw.seg[i]; - break; - case BLKIF_OP_DISCARD: - dst->u.discard.flag = src->u.discard.flag; - dst->u.discard.id = src->u.discard.id; - dst->u.discard.sector_number = src->u.discard.sector_number; - dst->u.discard.nr_sectors = src->u.discard.nr_sectors; - break; - case BLKIF_OP_INDIRECT: - dst->u.indirect.indirect_op = src->u.indirect.indirect_op; - dst->u.indirect.nr_segments = src->u.indirect.nr_segments; - dst->u.indirect.handle = src->u.indirect.handle; - dst->u.indirect.id = src->u.indirect.id; - dst->u.indirect.sector_number = src->u.indirect.sector_number; - barrier(); - j = min(MAX_INDIRECT_PAGES, INDIRECT_PAGES(dst->u.indirect.nr_segments)); - for (i = 0; i < j; i++) - dst->u.indirect.indirect_grefs[i] = - src->u.indirect.indirect_grefs[i]; - break; - default: - /* - * Don't know how to translate this op. Only get the - * ID so failure can be reported to the frontend. - */ - dst->u.other.id = src->u.other.id; - break; - } -} - -static inline void blkif_get_x86_64_req(struct blkif_request *dst, - struct blkif_x86_64_request *src) -{ - int i, n = BLKIF_MAX_SEGMENTS_PER_REQUEST, j; - dst->operation = READ_ONCE(src->operation); - switch (dst->operation) { - case BLKIF_OP_READ: - case BLKIF_OP_WRITE: - case BLKIF_OP_WRITE_BARRIER: - case BLKIF_OP_FLUSH_DISKCACHE: - dst->u.rw.nr_segments = src->u.rw.nr_segments; - dst->u.rw.handle = src->u.rw.handle; - dst->u.rw.id = src->u.rw.id; - dst->u.rw.sector_number = src->u.rw.sector_number; - barrier(); - if (n > dst->u.rw.nr_segments) - n = dst->u.rw.nr_segments; - for (i = 0; i < n; i++) - dst->u.rw.seg[i] = src->u.rw.seg[i]; - break; - case BLKIF_OP_DISCARD: - dst->u.discard.flag = src->u.discard.flag; - dst->u.discard.id = src->u.discard.id; - dst->u.discard.sector_number = src->u.discard.sector_number; - dst->u.discard.nr_sectors = src->u.discard.nr_sectors; - break; - case BLKIF_OP_INDIRECT: - dst->u.indirect.indirect_op = src->u.indirect.indirect_op; - dst->u.indirect.nr_segments = src->u.indirect.nr_segments; - dst->u.indirect.handle = src->u.indirect.handle; - dst->u.indirect.id = src->u.indirect.id; - dst->u.indirect.sector_number = src->u.indirect.sector_number; - barrier(); - j = min(MAX_INDIRECT_PAGES, INDIRECT_PAGES(dst->u.indirect.nr_segments)); - for (i = 0; i < j; i++) - dst->u.indirect.indirect_grefs[i] = - src->u.indirect.indirect_grefs[i]; - break; - default: - /* - * Don't know how to translate this op. Only get the - * ID so failure can be reported to the frontend. - */ - dst->u.other.id = src->u.other.id; - break; - } -} - #endif /* __XEN_BLKIF__BACKEND__COMMON_H__ */