[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [Xen-devel] [PATCH v14 02/11] x86/hvm/ioreq: simplify code and use consistent naming
This patch re-works much of the ioreq server initialization and teardown code: - The hvm_map/unmap_ioreq_gfn() functions are expanded to call through to hvm_alloc/free_ioreq_gfn() rather than expecting them to be called separately by outer functions. - Several functions now test the validity of the hvm_ioreq_page gfn value to determine whether they need to act. This means can be safely called for the bufioreq page even when it is not used. - hvm_add/remove_ioreq_gfn() simply return in the case of the default IOREQ server so callers no longer need to test before calling. - hvm_ioreq_server_setup_pages() is renamed to hvm_ioreq_server_map_pages() to mirror the existing hvm_ioreq_server_unmap_pages(). All of this significantly shortens the code. Signed-off-by: Paul Durrant <paul.durrant@xxxxxxxxxx> Reviewed-by: Roger Pau Monné <roger.pau@xxxxxxxxxx> Reviewed-by: Wei Liu <wei.liu2@xxxxxxxxxx> Acked-by: Jan Beulich <jbeulich@xxxxxxxx> --- Cc: Andrew Cooper <andrew.cooper3@xxxxxxxxxx> v3: - Rebased on top of 's->is_default' to 'IS_DEFAULT(s)' changes. - Minor updates in response to review comments from Roger. --- xen/arch/x86/hvm/ioreq.c | 182 ++++++++++++++++++----------------------------- 1 file changed, 69 insertions(+), 113 deletions(-) diff --git a/xen/arch/x86/hvm/ioreq.c b/xen/arch/x86/hvm/ioreq.c index da31918bb1..c21fa9f280 100644 --- a/xen/arch/x86/hvm/ioreq.c +++ b/xen/arch/x86/hvm/ioreq.c @@ -210,63 +210,75 @@ bool handle_hvm_io_completion(struct vcpu *v) return true; } -static int hvm_alloc_ioreq_gfn(struct domain *d, unsigned long *gfn) +static unsigned long hvm_alloc_ioreq_gfn(struct hvm_ioreq_server *s) { + struct domain *d = s->domain; unsigned int i; - int rc; - rc = -ENOMEM; + ASSERT(!IS_DEFAULT(s)); + for ( i = 0; i < sizeof(d->arch.hvm_domain.ioreq_gfn.mask) * 8; i++ ) { if ( test_and_clear_bit(i, &d->arch.hvm_domain.ioreq_gfn.mask) ) - { - *gfn = d->arch.hvm_domain.ioreq_gfn.base + i; - rc = 0; - break; - } + return d->arch.hvm_domain.ioreq_gfn.base + i; } - return rc; + return gfn_x(INVALID_GFN); } -static void hvm_free_ioreq_gfn(struct domain *d, unsigned long gfn) +static void hvm_free_ioreq_gfn(struct hvm_ioreq_server *s, + unsigned long gfn) { + struct domain *d = s->domain; unsigned int i = gfn - d->arch.hvm_domain.ioreq_gfn.base; - if ( gfn != gfn_x(INVALID_GFN) ) - set_bit(i, &d->arch.hvm_domain.ioreq_gfn.mask); + ASSERT(!IS_DEFAULT(s)); + ASSERT(gfn != gfn_x(INVALID_GFN)); + + set_bit(i, &d->arch.hvm_domain.ioreq_gfn.mask); } -static void hvm_unmap_ioreq_page(struct hvm_ioreq_server *s, bool buf) +static void hvm_unmap_ioreq_gfn(struct hvm_ioreq_server *s, bool buf) { struct hvm_ioreq_page *iorp = buf ? &s->bufioreq : &s->ioreq; + if ( iorp->gfn == gfn_x(INVALID_GFN) ) + return; + destroy_ring_for_helper(&iorp->va, iorp->page); + iorp->page = NULL; + + if ( !IS_DEFAULT(s) ) + hvm_free_ioreq_gfn(s, iorp->gfn); + + iorp->gfn = gfn_x(INVALID_GFN); } -static int hvm_map_ioreq_page( - struct hvm_ioreq_server *s, bool buf, unsigned long gfn) +static int hvm_map_ioreq_gfn(struct hvm_ioreq_server *s, bool buf) { struct domain *d = s->domain; struct hvm_ioreq_page *iorp = buf ? &s->bufioreq : &s->ioreq; - struct page_info *page; - void *va; int rc; - if ( (rc = prepare_ring_for_helper(d, gfn, &page, &va)) ) - return rc; - - if ( (iorp->va != NULL) || d->is_dying ) - { - destroy_ring_for_helper(&va, page); + if ( d->is_dying ) return -EINVAL; - } - iorp->va = va; - iorp->page = page; - iorp->gfn = gfn; + if ( IS_DEFAULT(s) ) + iorp->gfn = buf ? + d->arch.hvm_domain.params[HVM_PARAM_BUFIOREQ_PFN] : + d->arch.hvm_domain.params[HVM_PARAM_IOREQ_PFN]; + else + iorp->gfn = hvm_alloc_ioreq_gfn(s); - return 0; + if ( iorp->gfn == gfn_x(INVALID_GFN) ) + return -ENOMEM; + + rc = prepare_ring_for_helper(d, iorp->gfn, &iorp->page, &iorp->va); + + if ( rc ) + hvm_unmap_ioreq_gfn(s, buf); + + return rc; } bool is_ioreq_server_page(struct domain *d, const struct page_info *page) @@ -279,8 +291,7 @@ bool is_ioreq_server_page(struct domain *d, const struct page_info *page) FOR_EACH_IOREQ_SERVER(d, id, s) { - if ( (s->ioreq.va && s->ioreq.page == page) || - (s->bufioreq.va && s->bufioreq.page == page) ) + if ( (s->ioreq.page == page) || (s->bufioreq.page == page) ) { found = true; break; @@ -292,20 +303,30 @@ bool is_ioreq_server_page(struct domain *d, const struct page_info *page) return found; } -static void hvm_remove_ioreq_gfn( - struct domain *d, struct hvm_ioreq_page *iorp) +static void hvm_remove_ioreq_gfn(struct hvm_ioreq_server *s, bool buf) + { + struct domain *d = s->domain; + struct hvm_ioreq_page *iorp = buf ? &s->bufioreq : &s->ioreq; + + if ( IS_DEFAULT(s) || iorp->gfn == gfn_x(INVALID_GFN) ) + return; + if ( guest_physmap_remove_page(d, _gfn(iorp->gfn), _mfn(page_to_mfn(iorp->page)), 0) ) domain_crash(d); clear_page(iorp->va); } -static int hvm_add_ioreq_gfn( - struct domain *d, struct hvm_ioreq_page *iorp) +static int hvm_add_ioreq_gfn(struct hvm_ioreq_server *s, bool buf) { + struct domain *d = s->domain; + struct hvm_ioreq_page *iorp = buf ? &s->bufioreq : &s->ioreq; int rc; + if ( IS_DEFAULT(s) || iorp->gfn == gfn_x(INVALID_GFN) ) + return 0; + clear_page(iorp->va); rc = guest_physmap_add_page(d, _gfn(iorp->gfn), @@ -440,78 +461,25 @@ static void hvm_ioreq_server_remove_all_vcpus(struct hvm_ioreq_server *s) } static int hvm_ioreq_server_map_pages(struct hvm_ioreq_server *s, - unsigned long ioreq_gfn, - unsigned long bufioreq_gfn) + bool handle_bufioreq) { int rc; - rc = hvm_map_ioreq_page(s, false, ioreq_gfn); - if ( rc ) - return rc; - - if ( bufioreq_gfn != gfn_x(INVALID_GFN) ) - rc = hvm_map_ioreq_page(s, true, bufioreq_gfn); - - if ( rc ) - hvm_unmap_ioreq_page(s, false); - - return rc; -} - -static int hvm_ioreq_server_setup_pages(struct hvm_ioreq_server *s, - bool handle_bufioreq) -{ - struct domain *d = s->domain; - unsigned long ioreq_gfn = gfn_x(INVALID_GFN); - unsigned long bufioreq_gfn = gfn_x(INVALID_GFN); - int rc; - - if ( IS_DEFAULT(s) ) - { - /* - * The default ioreq server must handle buffered ioreqs, for - * backwards compatibility. - */ - ASSERT(handle_bufioreq); - return hvm_ioreq_server_map_pages(s, - d->arch.hvm_domain.params[HVM_PARAM_IOREQ_PFN], - d->arch.hvm_domain.params[HVM_PARAM_BUFIOREQ_PFN]); - } - - rc = hvm_alloc_ioreq_gfn(d, &ioreq_gfn); + rc = hvm_map_ioreq_gfn(s, false); if ( !rc && handle_bufioreq ) - rc = hvm_alloc_ioreq_gfn(d, &bufioreq_gfn); - - if ( !rc ) - rc = hvm_ioreq_server_map_pages(s, ioreq_gfn, bufioreq_gfn); + rc = hvm_map_ioreq_gfn(s, true); if ( rc ) - { - hvm_free_ioreq_gfn(d, ioreq_gfn); - hvm_free_ioreq_gfn(d, bufioreq_gfn); - } + hvm_unmap_ioreq_gfn(s, false); return rc; } static void hvm_ioreq_server_unmap_pages(struct hvm_ioreq_server *s) { - struct domain *d = s->domain; - bool handle_bufioreq = !!s->bufioreq.va; - - if ( handle_bufioreq ) - hvm_unmap_ioreq_page(s, true); - - hvm_unmap_ioreq_page(s, false); - - if ( !IS_DEFAULT(s) ) - { - if ( handle_bufioreq ) - hvm_free_ioreq_gfn(d, s->bufioreq.gfn); - - hvm_free_ioreq_gfn(d, s->ioreq.gfn); - } + hvm_unmap_ioreq_gfn(s, true); + hvm_unmap_ioreq_gfn(s, false); } static void hvm_ioreq_server_free_rangesets(struct hvm_ioreq_server *s) @@ -571,22 +539,15 @@ static int hvm_ioreq_server_alloc_rangesets(struct hvm_ioreq_server *s, static void hvm_ioreq_server_enable(struct hvm_ioreq_server *s) { - struct domain *d = s->domain; struct hvm_ioreq_vcpu *sv; - bool handle_bufioreq = !!s->bufioreq.va; spin_lock(&s->lock); if ( s->enabled ) goto done; - if ( !IS_DEFAULT(s) ) - { - hvm_remove_ioreq_gfn(d, &s->ioreq); - - if ( handle_bufioreq ) - hvm_remove_ioreq_gfn(d, &s->bufioreq); - } + hvm_remove_ioreq_gfn(s, false); + hvm_remove_ioreq_gfn(s, true); s->enabled = true; @@ -601,21 +562,13 @@ static void hvm_ioreq_server_enable(struct hvm_ioreq_server *s) static void hvm_ioreq_server_disable(struct hvm_ioreq_server *s) { - struct domain *d = s->domain; - bool handle_bufioreq = !!s->bufioreq.va; - spin_lock(&s->lock); if ( !s->enabled ) goto done; - if ( !IS_DEFAULT(s) ) - { - if ( handle_bufioreq ) - hvm_add_ioreq_gfn(d, &s->bufioreq); - - hvm_add_ioreq_gfn(d, &s->ioreq); - } + hvm_add_ioreq_gfn(s, true); + hvm_add_ioreq_gfn(s, false); s->enabled = false; @@ -637,6 +590,9 @@ static int hvm_ioreq_server_init(struct hvm_ioreq_server *s, INIT_LIST_HEAD(&s->ioreq_vcpu_list); spin_lock_init(&s->bufioreq_lock); + s->ioreq.gfn = gfn_x(INVALID_GFN); + s->bufioreq.gfn = gfn_x(INVALID_GFN); + rc = hvm_ioreq_server_alloc_rangesets(s, id); if ( rc ) return rc; @@ -644,7 +600,7 @@ static int hvm_ioreq_server_init(struct hvm_ioreq_server *s, if ( bufioreq_handling == HVM_IOREQSRV_BUFIOREQ_ATOMIC ) s->bufioreq_atomic = true; - rc = hvm_ioreq_server_setup_pages( + rc = hvm_ioreq_server_map_pages( s, bufioreq_handling != HVM_IOREQSRV_BUFIOREQ_OFF); if ( rc ) goto fail_map; -- 2.11.0 _______________________________________________ Xen-devel mailing list Xen-devel@xxxxxxxxxxxxxxxxxxxx https://lists.xenproject.org/mailman/listinfo/xen-devel
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